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Sample records for deep near-infrared photometry

  1. DEEP K{sub s} -NEAR-INFRARED SURFACE PHOTOMETRY OF 80 DWARF IRREGULAR GALAXIES IN THE LOCAL VOLUME

    SciTech Connect

    Fingerhut, Robin L.; McCall, Marshall L.; Argote, Mauricio; Cluver, Michelle E.; Nishiyama, Shogo; Rekola, Rami T. F.; Richer, Michael G.; Vaduvescu, Ovidiu; Woudt, Patrick A. E-mail: mccall@yorku.c E-mail: mcluver@ipac.caltech.ed E-mail: rareko@utu.f E-mail: ovidiuv@ing.iac.e

    2010-06-10

    We present deep near-infrared (K{sub s}) images and surface photometry for 80 dwarf irregular galaxies (dIs) within {approx}5 Mpc of the Milky Way. The galaxy images were obtained at five different facilities between 2004 and 2006. The image reductions and surface photometry have been performed using methods specifically designed for isolating faint galaxies from the high and varying near-infrared sky level. Fifty-four of the 80 dIs have surface brightness profiles which could be fit to a hyperbolic-secant (sech) function, while the remaining profiles could be fit to the sum of a sech and a Gaussian function. From these fits, we have measured central surface brightnesses, scale lengths, and integrated magnitudes. This survey is part of a larger study of the connection between large-scale structure and the global properties of dIs, the hypothesized building-blocks of more massive galaxies.

  2. WINGS: a WIde-field nearby Galaxy-cluster survey. III. Deep near-infrared photometry of 28 nearby clusters

    NASA Astrophysics Data System (ADS)

    Valentinuzzi, T.; Woods, D.; Fasano, G.; Riello, M.; D'Onofrio, M.; Varela, J.; Bettoni, D.; Cava, A.; Couch, W. J.; Dressler, A.; Fritz, J.; Moles, M.; Omizzolo, A.; Poggianti, B. M.; Kjærgaard, P.

    2009-07-01

    Context: This is the third paper in a series devoted to the WIde-field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long-term project aimed at gathering wide-field, multiband imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04near-infrared (J,K) photometric catalogs of 28 clusters of the WINGS sample and describes the procedures followed to construct them. Methods: The raw data has been reduced at CASU and special care has been devoted to the final coadding, drizzling technique, astrometric solution, and magnitude calibration for the WFCAM pipeline-processed data. We constructed the photometric catalogs based on the final calibrated, coadded mosaics (≈0.79 deg^2) in J (19 clusters) and K (27 clusters) bands. A customized interactive pipeline was used to clean the catalogs and to make mock images for photometric errors and completeness estimates. Results: We provide deep near-infrared photometric catalogs (90% complete in detection rate at total magnitudes J≈ 20.5, K≈ 19.4, and in classification rate at J≈19.5 and K≈ 18.5), giving positions, geometrical parameters, total and aperture magnitudes for all detected sources. For each field we classify the detected sources as stars, galaxies, and objects of “unknown” nature. Based on observations taken at the United Kingdom Infra-Red Telescope, operated by the Joint Astronomy Centre on behalf of the Science and Technology Facilities Council of the UK. J and K photometric catalogs are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/501/851

  3. S-CANDELS: The Spitzer-Cosmic Assembly Near-Infrared Deep Extragalactic Survey. Survey Design, Photometry, and Deep IRAC Source Counts

    NASA Astrophysics Data System (ADS)

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Dunlop, J. S.; Egami, E.; Faber, S. M.; Ferguson, H. C.; Grogin, N. A.; Hora, J. L.; Huang, J.-S.; Koekemoer, A. M.; Labbé, I.; Wang, Z.

    2015-06-01

    The Spitzer-Cosmic Assembly Deep Near-infrared Extragalactic Legacy Survey (S-CANDELS; PI G.Fazio) is a Cycle 8 Exploration Program designed to detect galaxies at very high redshifts (z\\gt 5). To mitigate the effects of cosmic variance and also to take advantage of deep coextensive coverage in multiple bands by the Hubble Space Telescope (HST) Multi-cycle Treasury Program CANDELS, S-CANDELS was carried out within five widely separated extragalactic fields: the UKIDSS Ultra-deep Survey, the Extended Chandra Deep Field South, COSMOS, the HST Deep Field North, and the Extended Groth Strip. S-CANDELS builds upon the existing coverage of these fields from the Spitzer Extended Deep Survey (SEDS), a Cycle 6 Exploration Program, by increasing the integration time from SEDS’ 12 hr to a total of 50 hr but within a smaller area, 0.16 deg2. The additional depth significantly increases the survey completeness at faint magnitudes. This paper describes the S-CANDELS survey design, processing, and publicly available data products. We present Infrared Array Camera (IRAC) dual-band 3.6+4.5 μ {{m}} catalogs reaching to a depth of 26.5 AB mag. Deep IRAC counts for the roughly 135,000 galaxies detected by S-CANDELS are consistent with models based on known galaxy populations. The increase in depth beyond earlier Spitzer/IRAC surveys does not reveal a significant additional contribution from discrete sources to the diffuse Cosmic Infrared Background (CIB). Thus it remains true that only roughly half of the estimated CIB flux from COBE/DIRBE is resolved.

  4. NEAR-INFRARED THERMAL EMISSION DETECTIONS OF A NUMBER OF HOT JUPITERS AND THE SYSTEMATICS OF GROUND-BASED NEAR-INFRARED PHOTOMETRY

    SciTech Connect

    Croll, Bryce; Albert, Loic; Lafreniere, David; Jayawardhana, Ray; Cushing, Michael; Moutou, Claire; Johnson, John Asher; Bonomo, Aldo S.; Deleuil, Magali; Fortney, Jonathan

    2015-03-20

    We present detections of the near-infrared thermal emission of three hot Jupiters and one brown dwarf using the Wide-field Infrared Camera (WIRCam) on the Canada-France-Hawaii Telescope (CFHT). These include Ks-band secondary eclipse detections of the hot Jupiters WASP-3b and Qatar-1b and the brown dwarf KELT-1b. We also report Y-band, K {sub CONT}-band, and two new and one reanalyzed Ks-band detections of the thermal emission of the hot Jupiter WASP-12b. We present a new reduction pipeline for CFHT/WIRCam data, which is optimized for high precision photometry. We also describe novel techniques for constraining systematic errors in ground-based near-infrared photometry, so as to return reliable secondary eclipse depths and uncertainties. We discuss the noise properties of our ground-based photometry for wavelengths spanning the near-infrared (the YJHK bands), for faint and bright stars, and for the same object on several occasions. For the hot Jupiters WASP-3b and WASP-12b we demonstrate the repeatability of our eclipse depth measurements in the Ks band; we therefore place stringent limits on the systematics of ground-based, near-infrared photometry, and also rule out violent weather changes in the deep, high pressure atmospheres of these two hot Jupiters at the epochs of our observations.

  5. Near-Infrared Absolute Photometry of the Uranian Satellites

    NASA Astrophysics Data System (ADS)

    Momary, T. W.; Baines, K. H.; Yanamandra-Fisher, P.; Lebofsky, L. A.; Golisch, W.

    1996-09-01

    We report the first absolutely-calibrated photometry of the Uranian satellites Miranda, Ariel, and Titania, in canonical near-infrared filters. These satellites were observed in July, August, and September of 1995, with the NSFCAM instrument at the NASA/IRTF. Results are reported for J, H, and K filters near 1.26, 1.62, and 2.21 mu m, and two special ~ 0.15-mu m-wide filters placed at 1.73 and 2.27 mu m. We measure an opposition surge for Miranda in the near-infrared of at least 0.48 mag/deg between phase angles of 1.0deg and 0.6deg , compared to a much shallower 0.015 +/- 0.006 mag/deg surge reported by Buratti et al. (Icarus 84, 203-214, 1990) for the visible. Miranda, which is brighter than Titania throughout the visible (Karkoschka et al., Icarus submitted), becomes the darker of the two satellites in the near- infrared, being some 20.5% dimmer than Titania in H, 8.8% dimmer in 1.73 mu m, and 9.1% dimmer in K. All three satellites are brightest at 1.73 mu m, with Ariel being fully 1/3 brighter than Miranda or Titania, whereas the three satellites are evenly spaced in albedo at 0.7 mu m, in the visible (Ariel being 15% brighter than Miranda, which is in turn 15% brighter than Titania). Specifically, Ariel reaches a peak full disk albedo of 0.4161 +/- 0.0125 for 1.0deg phase at 1.73 mu m. By comparison, the peak albedos of Miranda and Titania are only 0.2730 +/- 0.0082 and 0.2969 +/- 0.0089, respectively, at this wavelength (though these latter observations were at 2.4deg phase). Continuing the trend seen in the visible, Ariel is the brightest of the Uranian satellites throughout the near-infrared. Finally, all three satellites show a distinct increase in full-disk albedo between H and 1.73 mu m filters, on the order of 20%, which is the expected signature of water ice, in agreement with spectra taken by Brown and Cruikshank (Icarus 55, 83-92, 1983).

  6. Near-Infrared Absolute Photometry of the Saturnian Satellites

    NASA Astrophysics Data System (ADS)

    Momary, T. W.; Baines, K. H.; Yanamandra-Fisher, P. A.; Lebofsky, L. A.; Golisch, W.; Kaminski, C.

    1998-09-01

    We report absolutely-calibrated photometry of the Saturnian satellites in canonical near-infrared filters, including the first such spectrum of the leading side of Enceladus. The satellites were observed during Ring Plane Crossing in August and September of 1995 with the NSFCAM instrument at the NASA/IRTF. These observations were also simultaneous with those of the Uranian system, taken with the same instrument and filters, and analyzed by Baines et al. (Icarus 132, 266-284, 1998). Results are reported for J, H, and K filters near 1.27, 1.62, and 2.20 mu m, and two 0.1 mu m-wide filters centered at 1.73 and 2.27 mu m. We find that Enceladus has a peak brightness at 1.27 mu m with a geometric albedo of 0.898 +/- 0.063, in contrast to the Uranian satellites Miranda, Ariel, and Titania, which are relatively dim at this wavelength (albedos of roughly 0.3). The J-H band depth of Enceladus is about 30%, characteristic of spectra of Rhea, Tethys, and the trailing side of Iapetus, taken from Clark et al. (Icarus 58, 265-281, 1984) and convolved with our filters. By contrast, the darker Uranian satellites display a J-H band depth of less than 10%. From H to 1.73 mu m, the full-disk albedo of Enceladus increases by 27%, similar to the Uranian satellites. The dip in the Enceladus spectrum from J to H, as well as the subsequent rise from H to 1.73 mu m, are an expected signature of water ice. Finally, preliminary results for the albedos of Tethys, Dione, Rhea, and Mimas, as well as Enceladus, at 2.27 mu m compare favorably with the visible albedos of Buratti and Veverka (Icarus, 58, 254-264, 1984).

  7. Near-infrared Photometry of the Open Cluster NGC 2420

    NASA Astrophysics Data System (ADS)

    Hejazi, Neda; De Robertis, Michael M.; Dawson, Peter C.

    2016-01-01

    Open clusters have been used in numerous studies of stellar formation and evolution and have provided important constraints on theoretical stellar models. In this study, we carried out deep near-infrared imaging (I, J, H and Ks bands) with the 1024×1024 CFHT-IR camera at the Cassegrain focus of the Canada-France-Hawaii 3.6 m telescope of two fields in the relatively old open cluster, NGC 2420. This cluster was selected due to its relatively low metallicity, [Fe/H] ˜ -0.5, and rather high Galactic latitude (for an open cluster), b ≈ 20°, reducing the effects of reddening as well as reducing the extent of contamination by non-members of the cluster. The empirical data were calibrated using 2MASS and Stetson standards in the field. Non-cluster stars were removed using a field-cluster decontamination algorithm. By fitting available theoretical isochrones to the observed color-magnitude diagrams, we have been able to estimate the age, metallicity and distance of the cluster which are compared to previous studies.

  8. Optical and near infrared photometry of Butcher-Oemler clusters

    NASA Technical Reports Server (NTRS)

    Shier, Lisa M.; Rieke, Marcia J.

    1993-01-01

    Rich clusters of galaxies at moderate redshifts (z approx. .3) have a larger proportion of optically blue galaxies than their low redshift counterparts. Spectroscopic examination of the blue galaxies by various authors has shown that the blue galaxies are generally Seyferts, show evidence for recent star formation, or are foreground objects. Unfortunately, spectroscopy is too time consuming to be used on large samples. Thus, we have looked for a way to separate Seyferts, starbursts, ellipticals and nonmembers using photometry alone. Five moderate redshift clusters, Abell numbers 777, 963, 1758, 1961 and 2218, have been observed in the V, R and K bands. We model the spectral energy distributions of various kinds of galaxies found in clusters and derive observed colors. We have modeled the spectral energy distributions (SED) of several kinds of galaxies and compute their colors as a function of redshift. We expect to see ellipticals, spirals, starbursts, post-starburst and Seyfert galaxies. The SED of elliptical and Sbc galaxies was observed by Rieke and Rieke. The SEDs for the starburst galaxies was created by adding a reddened 10(exp 8) year old burst to a spiral galaxy SED. The post-starburst (E+A) galaxy SEDs are composed of a slightly reddened 10(exp 9) year old burst and elliptical galaxy SED. SEDs for the Seyferts were created by adding a v(exp -1.1) power law, and a hot dust thermal spectrum to the Sbc. From the SEDs the colors of galaxies at various redshifts with assorted filters were computed. Lilly & Gunn (1985) have optical and infrared photometry for a sample of galaxies in CL0024+1654 observed spectroscopically by Dressler, Gunn and Schneider (1985). We have used this data to choose the most appropriate SEDs for our starburst and post-starburst models. The most likely explanation for the optically blue colors in most cluster galaxies is star formation. Very few galaxies lie in the Seyfert locus. Abel 1758 has more Seyfert candidates than the other

  9. Using near infrared light for deep sea mining observation systems

    NASA Astrophysics Data System (ADS)

    Lu, Huimin; Li, Yujie; Li, Xin; Yang, Jianmin; Serikawa, Seiichi

    2015-10-01

    In this paper, we design a novel deep-sea near infrared light based imaging equipment for deep-sea mining observation systems. The spectral sensitivity peaks are in the red region of the invisible spectrum, ranging from 750nm to 900nm. In addition, we propose a novel underwater imaging model that compensates for the attenuation discrepancy along the propagation path. The proposed model fully considered the effects of absorption, scattering and refraction. We also develop a locally adaptive Laplacian filtering for enhancing underwater transmission map after underwater dark channel prior estimation. Furthermore, we propose a spectral characteristic-based color correction algorithm to recover the distorted color. In water tank experiments, we made a linear scale of eight turbidity steps ranging from clean to heavily scattered by adding deep sea soil to the seawater (from 500 to 2000 mg/L). We compared the results of different turbidity underwater scene, illuminated alternately with near infrared light vs. white light. Experiments demonstrate that the enhanced NIR images have a reasonable noise level after the illumination compensation in the dark regions and demonstrates an improved global contrast by which the finest details and edges are significantly enhanced. We also demonstrate that the effective distance of the designed imaging system is about 1.5 meters, which can meet the requirement of micro-terrain observation around the deep-sea mining systems. Remotely Operated Underwater Vehicle (ROV)-based experiments also certified the effectiveness of the proposed method.

  10. Near-infrared surface photometry of a sample of barred galaxies

    NASA Astrophysics Data System (ADS)

    Gadotti, D. A.; Athanassoula, E.; Carrasco, L.; Bosma, A.; de Souza, R. E.; Recillas, E.

    2007-11-01

    We have obtained deep J and Ks images of a sample of nine barred galaxies in order to collect a reliable and homogeneous set of images to which N-body simulations of barred galaxies will be compared. The observations were performed using the new near-infrared camera available at the 2.1-m telescope of the Observatorio Astrofísico Guillermo Haro (OAGH) in Cananea, Sonora, Mexico. We present the results of surface photometry techniques applied to the observed images, as well as to the deprojected images. These results include radial profiles of surface brightness (elliptically averaged), colour, position angle, ellipticity and the b4 Fourier component. In addition, we present isophotal maps, colour maps, surface brightness profiles along the bar major and minor axes, characteristic radial scalelengths and bar length estimates. We discuss how projection effects can influence these measurements and the uncertainties introduced by deprojecting galaxy images. We show that analytical expressions can be used to obtain reliable estimates of deprojected bar lengths, ellipticities and position angles directly from the observed images. These expressions are based on the assumption that the outer parts of the bar are vertically thin, as shown by theoretical work. The usefulness of our data in addressing issues on bar formation and evolution is also discussed. In particular, we present results showing a steep drop in the ellipticity profile, as expected for bar formation processes in which the dark matter halo plays a fundamental role. Furthermore, we show that the location of this drop is a good indicator of the end of the bar in strongly barred galaxies, as predicted by numerical models.

  11. Near-infrared photometry and spectroscopy of the low Galactic latitude globular cluster 2MASS-GC 03

    NASA Astrophysics Data System (ADS)

    Carballo-Bello, Julio A.; Ramírez Alegría, S.; Borissova, J.; Smith, L. C.; Kurtev, R.; Lucas, P. W.; Moni Bidin, Ch.; Alonso-García, J.; Minniti, D.; Palma, T.; Dékány, I.; Medina, N.; Moyano, M.; Villanueva, V.; Kuhn, M. A.

    2016-10-01

    We present deep near-infrared photometry and spectroscopy of the globular cluster 2MASS-GC 03 projected in the Galactic disc using MMT and Magellan Infrared Spectrograph on the Clay Telescope (Las Campanas Observatory) and VISTA Variables in the Via Lactea Survey data. Most probable cluster member candidates were identified from near-infrared photometry. Out of 10 candidates that were followed-up spectroscopically, 5 have properties of cluster members, from which we calculate <[Fe/H]>= - 0.9 ± 0.2 and a radial velocity of = - 78 ± 12 km s-1. A distance of 10.8 kpc is estimated from three likely RR Lyrae members. Given that the cluster is currently at a distance of 4.2 kpc from the Galactic Centre, the cluster's long survival time of an estimated 11.3 ± 1.2 Gyr strengthens the case for its globular-cluster nature. The cluster has a hint of elongation in the direction of the Galactic Centre.

  12. A local attenuation filter for accurate photometry of near-infrared bright stars

    NASA Astrophysics Data System (ADS)

    Nagayama, Takahiro

    2016-07-01

    I have developed a special ND filter (Local Attenuation Filter) for observing bright near-infrared stars. This filter is a 60mm diameter with a 4mm thickness, on which an attenuation (0.02% transparency) patch with an 8mm diameter is coated. This filter is expected to be installed near the focal plane of telescope, and the flux through this patch is attenuated. Using this filter, we can observe the attenuated bright star together with not affected field stars as reference for relative photometry. This filter has been installed to the IRSF 1.4m telescope and used for the monitoring of NIR bright stars, for example, η Car.

  13. PRIME: A Deep Near-infrared Survey Mission Concept

    NASA Astrophysics Data System (ADS)

    Zheng, W.; Ford, H. C.; Davidsen, A. F.; Kruk, J. W.; Tsvetanov, Z. I.; Szalay, A. S.; Hartig, G.; Postman, M.; Stockman, H. S.; Thompson, R.; Shu, P. K.; Lenzen, R.; Rix, H.-W.; Mark, D.; McGuffey, D.

    2000-12-01

    PRIME (The Primordial Explorer) is a proposed mission that has been selected for NASA SMEX concept study. It will carry out a deep sky survey from space in four near-infrared bands between 0.9-3.5 micron. The 0.75m telescope will survey a quarter of the sky to AB magnitude of approximately 24 in 1.5 years. Deeper surveys in selected sky regions are also planned. PRIME will reach an epoch during which the first quasars, galaxies and clusters of galaxies were formed in the early Universe, discover hundreds of Type-Ia supernovae to be used in measuring the acceleration of the expanding Universe, and detect hundreds of brown dwarfs and even Jupiter-size planets in the vicinity of the solar system. Most of these objects are so rare that they may be identified only in large and deep surveys. PRIME will serve as a pilot mission for the Next Generation Space Telescope (NGST) supplying rare targets for NGST spectroscopy and deep imaging. Combining PRIME with other surveys (SDSS, GALEX) will yield the largest astronomical database ever built.

  14. The VIRMOS deep imaging survey. IV. Near-infrared observations

    NASA Astrophysics Data System (ADS)

    Iovino, A.; McCracken, H. J.; Garilli, B.; Foucaud, S.; Le Fèvre, O.; Maccagni, D.; Saracco, P.; Bardelli, S.; Busarello, G.; Scodeggio, M.; Zanichelli, A.; Paioro, L.; Bottini, D.; Le Brun, V.; Picat, J. P.; Scaramella, R.; Tresse, L.; Vettolani, G.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bolzonella, M.; Cappi, A.; Charlot, S.; Ciliegi, P.; Contini, T.; Franzetti, P.; Gavignaud, I.; Guzzo, L.; Ilbert, O.; Marano, B.; Marinoni, C.; Mazure, A.; Meneux, B.; Merighi, R.; Paltani, S.; Pellò, R.; Pollo, A.; Pozzetti, L.; Radovich, M.; Zamorani, G.; Zucca, E.; Bertin, E.; Bondi, M.; Bongiorno, A.; Cucciati, O.; Gregorini, L.; Mathez, G.; Mellier, Y.; Merluzzi, P.; Ripepi, V.; Rizzo, D.

    2005-11-01

    In this paper we present a new deep, wide-field near-infrared imaging survey. Our J- and K-band observations in four separate fields (0226-04, 2217+00, 1003+02, 1400+05) complement optical BVRI, ultraviolet and spectroscopic observations undertaken as part of the VIMOS-VLT deep survey (VVDS). In total, our survey spans ~400 arcmin2. Our catalogues are reliable in all fields to at least K˜20.75 and J˜21.50 (defined as the magnitude where object contamination is less than 10% and completeness greater than 90%). Taken together these four fields represents a unique combination of depth, wavelength coverage and area. Most importantly, our survey regions span a broad range of right ascension and declination which allow us to make a robust estimate of the effects of cosmic variance. We describe the complete data reduction process from raw observations to the construction of source lists and outline a comprehensive series of tests carried out to characterise the reliability of the final catalogues. From simulations we determine the completeness function of each final stacked image, and estimate the fraction of spurious sources in each magnitude bin. We compare the statistical properties of our catalogues with literature compilations. We find that our J- and K-selected galaxy counts are in good agreement with previously published works, as are our (J-K) versus K colour-magnitude diagrams. Stellar number counts extracted from our fields are consistent with a synthetic model of our galaxy. Using the location of the stellar locus in colour-magnitude space and the measured field-to-field variation in galaxy number counts we demonstrate that the absolute accuracy of our photometric calibration is at the 5% level or better. Finally, an investigation of the angular clustering of K-selected extended sources in our survey displays the expected scaling behaviour with limiting magnitude, with amplitudes in each magnitude bin in broad agreement with literature values. In summary

  15. NEAR-INFRARED (JHK) PHOTOMETRY OF 131 NORTHERN GALACTIC CLASSICAL CEPHEIDS

    SciTech Connect

    Monson, Andrew J.; Pierce, Michael J.

    2011-03-15

    Near-infrared photometric measurements for 131 Northern Galactic Cepheids are presented. The Cepheid light curves are sampled with an average of 22 measurements per star fully covering the phase of each Cepheid. The J, H, and K light curves for each Cepheid were uniformly interpolated to find the intensity mean magnitudes within each band. The results are consistent within {+-}1% for 26 stars in common with previous studies. This paper is the first in a projected series of two papers which will provide additional fundamental data for Cepheids in the Galaxy, namely, NIR photometry and line-of-sight extinction. In the course of this project, 93 additional variables were fortuitously observed within the Cepheid program fields, 82 of which have previously not been identified.

  16. Near-infrared surface photometry and morphology in virgo cluster spiral galaxy nuclear regions

    NASA Astrophysics Data System (ADS)

    Rauscher, Bernard J.

    1995-04-01

    This paper presents very high spatial resolution (seeing 0.75 arcsec FWHM) K band surface photometry of 15 Virgo cluster spiral galaxy nuclear regions (radii less then 1 kpc). It presents B and I CCD images of 13 of these galaxies. The goals of the study were: (1) to begin to establish a K band baseline of normal spiral galaxy nuclear regions against which peculiar galaxies may be compared, (2) to provide better contsraints on N-body models, and (3) to complement near-infrared studies of large scale structure in spiral galaxies with very high resolution imaging of the important nuclear regions. The principle findings are (1) between 1/4 and 1/3 of these nuclear regions show K band evidence of traxiality, (2) approximately 1/2 of these galaxies have axisymmetric nuclear regions, and (3) NGC 4321 has a bar that is not detectable in the optical images.

  17. Deep near-infrared survey of the Southern Sky (DENIS)

    NASA Technical Reports Server (NTRS)

    Deul, E.

    1992-01-01

    DENIS (Deep Near-Infrared Survey of the Southern Sky) will be the first complete census of astronomical sources in the near-infrared spectral range. The challenges of this novel survey are both scientific and technical. Phenomena radiating in the near-infrared range from brown dwarfs to galaxies in the early stages of cosmological evolution, the scientific exploitation of data relevant over such a wide range requires pooling expertise from several of the leading European astronomical centers. The technical challenges of a project which will provide an order of magnitude more sources than given by the IRAS space mission, and which will involve advanced data-handling and image-processing techniques, likewise require pooling of hardware and software resources, as well as of human expertise. The DENIS project team is composed of some 40 scientists, computer specialists, and engineers located in 5 European Community countries (France, Germany, Italy, The Netherlands, and Spain), with important contributions from specialists in Australia, Brazil, Chile, and Hungary. DENIS will survey the entire southern sky in 3 colors, namely in the I band at a wavelength of 0.8 micron, in the 1.25 micron J band, and in the 2.15 micron K' band. The sensitivity limits will be 18th magnitude in the I band, 16th in the J band, and 14.5th in the K' band. The angular resolution achieved will be 1 arcsecond in the I band, and 3.0 arcseconds in the J and K' bands. The European Southern Observatory 1 m telescope on La Silla will be dedicated to survey use during operations expected to last four years, commencing in late 1993. DENIS aims to provide the astronomical community with complete digitized infrared images of the full southern sky and a catalogue of extracted objects, both of the best quality and in readily accessible form. This will be achieved through dedicated software packages and specialized catalogues, and with assistance from the Leiden and Paris Data Analysis Centers. The data

  18. Galaxy Evolution from Deep Optical and Near-Infrared Surveys

    NASA Astrophysics Data System (ADS)

    Moustakas, Leonidas Alexander

    1998-09-01

    We use very deep optical and near-infrared imaging surveys to set constraints on galaxy evolution models, based on the numbers, colors, and morphologies of infrared-excess galaxies that are found in the field. We concentrate on a curious population of extremely faint (K > 20) infrared-excess galaxies whose blue-optical colors are not consistent with the expectations of any passive evolution models. These ``faint red-outlier galaxies'' (FROGs) are distinct from the redder and brighter ``extremely red objects'' (EROs; R-K~=6 ). In a concerted effort to identify a good sample of FROG s and to study their properties, we used Keck/NIRC to image several independent high-galactic latitude fields. Much of the analysis presented here is drawn from a very deep 3.24 arcmin2 K-band ( Klim~24 at 3σ) mosaic in the deep Westphal HST/WFPC2 pointing of the Groth Survey Strip, for which F606W and F814W data were publically available. The surface density of FROGs is found to be ~ 3.3 +/- 1 arcmin-2, more than ten times that of EROs. Whereas reliable photometric redshifts are not forthcoming without the development of more relevant models, the colors are broadly consistent with the redshift range 1.2 < z < 2.3. If placed at z ~ 1.5, FROGs occur at space densities of about 10% of the local f* space density of K-selected galaxies. To map wavelength-dependent morphologies of two FROGs, we observed a portion of our main survey field with HST/NICMOS imaging through the F160W (1.6 μm) filter. The target was resolved into two r~=0''.6 objects with similar colors, separated by ~0''.7. This is suggestive of old and dynamically-relaxed systems. The colors of FROGs are not satisfactorily fit by dust-reddened Bruzual-Charlot models at any redshift and for a broad range of assumed star formation histories. The best possible fits are consistent with very large amounts of reddening, E(B - V) ~ 1. If the infrared-excess in EROs and FROGs is taken to be entirely due to the effects of dust, then we

  19. NEAR-INFRARED PHOTOMETRY OF Y DWARFS: LOW AMMONIA ABUNDANCE AND THE ONSET OF WATER CLOUDS

    SciTech Connect

    Leggett, S. K.; Morley, Caroline V.; Marley, M. S.; Saumon, D.

    2015-01-20

    We present new near-infrared photometry for seven late-type T dwarfs and nine Y-type dwarfs, and lower limit magnitudes for a tenth Y dwarf, obtained at Gemini Observatory. We also present a reanalysis of H-band imaging data from the Keck Observatory Archive, for an 11th Y dwarf. These data are combined with earlier MKO-system photometry, Spitzer and WISE mid-infrared photometry, and available trigonometric parallaxes, to create a sample of late-type brown dwarfs that includes 10 T9-T9.5 dwarfs or dwarf systems, and 16 Y dwarfs. We compare the data to our models, which include updated H{sub 2} and NH{sub 3} opacity, as well as low-temperature condensate clouds. The models qualitatively reproduce the trends seen in the observed colors; however, there are discrepancies of around a factor of two in flux for the Y0-Y1 dwarfs, with T {sub eff} ≈ 350-400 K. At T {sub eff} ∼ 400 K, the problems could be addressed by significantly reducing the NH{sub 3} absorption, for example by halving the abundance of NH{sub 3} possibly by vertical mixing. At T {sub eff} ∼ 350 K, the discrepancy may be resolved by incorporating thick water clouds. The onset of these clouds might occur over a narrow range in T {sub eff}, as indicated by the observed small change in 5 μm flux over a large change in J – W2 color. Of the known Y dwarfs, the reddest in J –W2 are WISEP J182831.08+265037.8 and WISE J085510.83–071442.5. We interpret the former as a pair of identical 300-350 K dwarfs, and the latter as a 250 K dwarf. If these objects are ∼3 Gyr old, their masses are ∼10 and ∼5 Jupiter-masses, respectively.

  20. Near Infrared Absolute Photometry of Saturn's Satellites at Ring Plane Crossing

    NASA Astrophysics Data System (ADS)

    Momary, T. W.; Baines, K. H.; Yanamandra-Fisher, P. A.; Buratti, B. J.; Lebofsky, L. A.

    1999-09-01

    Absolutely-calibrated multispectral photometry of nine Saturnian satellites, including the leading side of Enceladus, are presented for canonical near-infrared filters. The satellites were observed during Ring Plane Crossing in August/September 1995 with the NSFCAM instrument at the NASA/IRTF. Observations were contemporaneous with those of the Uranian system, acquired by Baines et al. (Icarus 132, 266-284, 1998), using the same instrument and filters. Results are reported for J, H, and K filters near 1.27, 1.62, and 2.20 microns, and two filters centerd at 1.73 and 2.27 microns. We find that the spectrum and absolute brightness of Enceladus is consistent with fresh water ice, relatively uncontaminated by the kinds of low albedo, spectrally neutral materials found in the Uranian system. The satellite's peak brightness is at 1.27 microns with a geometric albedo of 0.904 +/- 0.063, in contrast to the Uranian satellites Miranda, Ariel, and Titania, which are one third as bright at this wavelength. The J-H band depth of Enceladus is about 30% contrasting with the darker Uranian satellites' J-H band depth of less than 10%. Enceladus shows a large near-infrared opposition surge of 0.0817 mag /degree between 3.51 deg and 0.39 deg solar phase, perhaps consistent with a surface coated with highly backscattering fresh water-ice frost. Dione, Janus, and Epimetheus have brighter leading sides than trailing. The opposite is true for Enceladus, consistent with 0.89 micron measurements of Buratti et al. (Icarus, 136, 223-231, 1998) and with the suggestion by Showalter et al. (Icarus, 94, 451-473, 1991) that negatively charged E-ring particles would preferentially impact Enceladus' trailing side. Finally, our 2.27 micron albedos for Prometheus, Janus, Epimetheus, Mimas, Tethys, Dione, Rhea, and Hyperion, as well as Enceladus, are comparable to the visible albedos reported by Buratti and Veverka (Icarus, 58, 254-264, 1984).

  1. Near-infrared photometry of WISE J085510.74-071442.5

    NASA Astrophysics Data System (ADS)

    Zapatero Osorio, M. R.; Lodieu, N.; Béjar, V. J. S.; Martín, E. L.; Ivanov, V. D.; Bayo, A.; Boffin, H. M. J.; Mužić, K.; Minniti, D.; Beamín, J. C.

    2016-08-01

    Aims: We aim at obtaining near-infrared photometry and deriving the mass, age, temperature, and surface gravity of WISE J085510.74-071442.5 (J0855-0714), which is the coolest object beyond the solar system currently known. Methods: We used publicly available data from the archives of the Hubble Space Telescope (HST) and the Very Large Telescope (VLT) to determine the emission of this source at 1.153 μm (F110W) and 1.575 μm (CH4-off). J0855-0714 was detected at both wavelengths with a signal-to-noise ratio of ≈10 (F110W) and ≈4 (CH4-off) at the peak of the corresponding point-spread-functions. Results: This is the first detection of J0855-0714 in the H-band wavelengths. We measured 26.31 ± 0.10 and 23.22 ± 0.35 mag in F110W and CH4-off (Vega system). J0855-0714 remains unresolved in the HST images that have a spatial resolution of 0.22''. Companions at separations of 0.5 AU (similar mass and brightness) and at ~1 AU (≈1 mag fainter in the F110W filter) are discarded. By combining the new data with published photometry, including non-detections, we build the spectral energy distribution of J0855-0714 from 0.89 through 22.09 μm, and contrast it against current solar-metallicity models of planetary atmospheres. We determine that the best spectral fit yields a temperature of 225-250 K, a bolometric luminosity of log L/L⊙ = -8.57, and a high surface gravity of log g = 5.0 (cm s-2), which suggests an old age although a gravity this high is not fully compatible with evolutionary models. After comparing our data with the cooling theory for brown dwarfs and planets, we infer a mass in the interval 2-10 MJup for ages of 1-12 Gyr and high atmospheric gravities of log g ⪆ 3.5 (cm s-2). If it had the age of the Sun, J0855-0714 would be a ≈5-MJup free-floating planetary-mass object. Conclusions: J0855-0714 meets the mass values previously determined for free-floating planetary-mass objects discovered in star-forming regions and young stellar clusters. Based on

  2. PRIME: A Deep Near-Infrared Survey Project

    NASA Astrophysics Data System (ADS)

    Omont, A.; Prime Team; Zheng, W.; Ford, H. C.; Kruk, J. W.; Tsvetanov, Z. I.; Szalay, A. S.; Shu, P. K.; Greenhouse, M. A.; Hartig, G.; Postman, M.; Stockman, H. S.; Voit, G. M.; Lenzen, R.; Rix, H.-W.; Kent, S.; Stoughton, C.; Mellier, Y.

    PRIME is a proposed space mission for a deep survey of 25% to 100% of the sky in four near-IR bands (0.9-3.5 μm), to M AB ≈ 24 (K ≈ 22). The PRIME survey should be ~ 600 times deeper than 2MASS. Deeper surveys in selected regions are planned. Its main goal is to find the first massive objects formed: quasars up to z = 15-25 if any, galaxies up to z ~20, clusters of galaxies up to z ~ 3-5. PRIME should also be a major step in the study of brown dwarfs and nearby free floating warm planets, and serve many other goals, in particular as a pilot mission for NGST. It should be a central piece of The Virtual Observatory, complementary to other surveys.

  3. Near-Infrared and Visual Photometry of the Mira Variables V Tau and X AUR

    NASA Astrophysics Data System (ADS)

    Henson, G. D.

    1997-05-01

    We have been using a system of narrow-band, near-infrared filters to monitor changes in the infrared continuum magnitude and spectral type of several Mira variables (Rebel and Henson 1996, Bull. A.A.S., 28, 1399). Observations in V were added to the program at the beginning of 1997. We are now building simultaneous visual and near-infrared light curves with corresponding spectral type and color index variations. A comparison of the visual and infrared behavior will allow us to determine whether peculiarities in the visual light curves for these stars can be attributed to differential line blanketing effects or the phasing of temperature and diameter variations. Curves for a complete cycle of the short period Miras, V Tau and X Aur, are presented and the results discussed.

  4. CONTAMINATION OF BROADBAND PHOTOMETRY BY NEBULAR EMISSION IN HIGH-REDSHIFT GALAXIES: INVESTIGATIONS WITH KECK'S MOSFIRE NEAR-INFRARED SPECTROGRAPH

    SciTech Connect

    Schenker, Matthew A; Ellis, Richard S; Konidaris, Nick P; Stark, Daniel P

    2013-11-01

    Earlier work has raised the potential importance of nebular emission in the derivation of the physical characteristics of high-redshift Lyman break galaxies. Within certain redshift ranges, and especially at z ≅ 6-7, such lines may be strong enough to reduce estimates of the stellar masses and ages of galaxies compared with those derived assuming the broadband photometry represents stellar light alone. To test this hypothesis at the highest redshifts where such lines can be probed with ground-based facilities, we examine the near-infrared spectra of a representative sample of 28 3.0 < z < 3.8 Lyman break galaxies using the newly commissioned MOSFIRE near-infrared spectrograph at the Keck I telescope. We use these data to derive the rest-frame equivalent widths (EWs) of [O III] emission and show that these are comparable with estimates derived using the spectral energy distribution (SED) fitting technique introduced for sources of known redshift by Stark et al. Although our current sample is modest, its [O III] EW distribution is consistent with that inferred for Hα based on SED fitting of Stark et al.'s larger sample of 3.8 < z < 5 galaxies. For a subset of survey galaxies, we use the combination of optical and near-infrared spectroscopy to quantify kinematics of outflows in z ≅ 3.5 star-forming galaxies and discuss the implications for reionization measurements. The trends we uncover underline the dangers of relying purely on broadband photometry to estimate the physical properties of high-redshift galaxies and emphasize the important role of diagnostic spectroscopy.

  5. Contamination of Broadband Photometry by Nebular Emission in High-redshift Galaxies: Investigations with Keck's MOSFIRE Near-infrared Spectrograph

    NASA Astrophysics Data System (ADS)

    Schenker, Matthew A.; Ellis, Richard S.; Konidaris, Nick P.; Stark, Daniel P.

    2013-11-01

    Earlier work has raised the potential importance of nebular emission in the derivation of the physical characteristics of high-redshift Lyman break galaxies. Within certain redshift ranges, and especially at z ~= 6-7, such lines may be strong enough to reduce estimates of the stellar masses and ages of galaxies compared with those derived assuming the broadband photometry represents stellar light alone. To test this hypothesis at the highest redshifts where such lines can be probed with ground-based facilities, we examine the near-infrared spectra of a representative sample of 28 3.0 < z < 3.8 Lyman break galaxies using the newly commissioned MOSFIRE near-infrared spectrograph at the Keck I telescope. We use these data to derive the rest-frame equivalent widths (EWs) of [O III] emission and show that these are comparable with estimates derived using the spectral energy distribution (SED) fitting technique introduced for sources of known redshift by Stark et al. Although our current sample is modest, its [O III] EW distribution is consistent with that inferred for Hα based on SED fitting of Stark et al.'s larger sample of 3.8 < z < 5 galaxies. For a subset of survey galaxies, we use the combination of optical and near-infrared spectroscopy to quantify kinematics of outflows in z ~= 3.5 star-forming galaxies and discuss the implications for reionization measurements. The trends we uncover underline the dangers of relying purely on broadband photometry to estimate the physical properties of high-redshift galaxies and emphasize the important role of diagnostic spectroscopy.

  6. MOIRCS Deep Survey. IX. Deep Near-Infrared Imaging Data and Source Catalog

    NASA Astrophysics Data System (ADS)

    Kajisawa, Masaru; Ichikawa, Takashi; Tanaka, Ichi; Yamada, Toru; Akiyama, Masayuki; Suzuki, Ryuji; Tokoku, Chihiro; Katsuno Uchimoto, Yuka; Konishi, Masahiro; Yoshikawa, Tomohiro; Nishimura, Tetsuo; Omata, Koji; Ouchi, Masami; Iwata, Ikuru; Hamana, Takashi; Onodera, Masato

    2011-03-01

    We present deep J-, H-, and Ks-band imaging data of the MOIRCS Deep Survey (MODS), which was carried out with the Multi-Object Infrared Camera and Spectrograph (MOIRCS) mounted on the Subaru Telescope in the GOODS-North region. The data reach 5σ total limiting magnitudes for point sources of J = 23.9, H = 22.8, and Ks = 22.8 (Vega magnitude) over 103 arcmin2 (wide field). In 28 arcmin2 of the survey area, which is an ultra-deep field of the MODS (deep field), the data reach 5σ depths of J = 24.8, H = 23.4, and Ks = 23.8. The spatial resolutions of the combined images are FWHM ˜0''.6 and ˜0''.5 for the wide and deep fields in all bands, respectively. Combining the MODS data with the multi-wavelength public data taken with the HST, Spitzer, and other ground-based telescopes in the GOODS field, we constructed a multi-wavelength photometric catalog of Ks-selected sources. Using the catalog, we present Ks-band number counts and near-infrared color distribution of the detected objects; we also demonstrate some selection techniques with the NIR colors for high redshift galaxies. These data and catalog are publicly available via Internet.

  7. THE ARAUCARIA PROJECT. A DISTANCE DETERMINATION TO THE LOCAL GROUP SPIRAL M33 FROM NEAR-INFRARED PHOTOMETRY OF CEPHEID VARIABLES

    SciTech Connect

    Gieren, Wolfgang; Pietrzynski, Grzegorz; Graczyk, Dariusz E-mail: pietrzyn@hubble.cfm.udec.cl; and others

    2013-08-10

    Motivated by an amazing range of reported distances to the nearby Local Group spiral galaxy M33, we have obtained deep near-infrared photometry for 26 long-period Cepheids in this galaxy with the ESO Very Large Telescope. From the data, we constructed period-luminosity relations in the J and K bands which together with previous optical VI photometry for the Cepheids by Macri et al. were used to determine the true distance modulus of M33, and the mean reddening affecting the Cepheid sample with the multiwavelength fit method developed in the Araucaria Project. We find a true distance modulus of 24.62 for M33, with a total uncertainty of {+-}0.07 mag which is dominated by the uncertainty on the photometric zero points in our photometry. The reddening is determined as E(B - V) = 0.19 {+-} 0.02, in agreement with the value used by the Hubble Space Telescope Key Project of Freedman et al. but in some discrepancy with other recent determinations based on blue supergiant spectroscopy and an O-type eclipsing binary which yielded lower reddening values. Our derived M33 distance modulus is extremely insensitive to the adopted reddening law. We show that the possible effects of metallicity and crowding on our present distance determination are both at the 1%-2% level and therefore minor contributors to the total uncertainty of our distance result for M33.

  8. Near-infrared photometry and spectroscopy of the unusual minor planet 5145 Pholus (1992AD)

    NASA Technical Reports Server (NTRS)

    Davies, John K.; Sykes, Mark V.; Cruikshank, Dale P.

    1993-01-01

    Near-IR photometry and spectroscopy of 5145 Pholus reveals that the visual to IR colors are unusually red and appear to show evidence for complex organic solids and/or ices on the surface. No compelling match is found with any present measurements of single-component ice or tholin samples.

  9. NEAR-INFRARED TRANSIT PHOTOMETRY OF THE EXOPLANET HD 149026b

    SciTech Connect

    Carter, Joshua A.; Winn, Joshua N.; Gilliland, Ronald; Holman, Matthew J.

    2009-05-01

    The transiting exoplanet HD 149026b is an important case for theories of planet formation and planetary structure, for the planet's relatively small size has been interpreted as evidence for a highly metal-enriched composition. We present observations of four transits with the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) on the Hubble Space Telescope within a wavelength range of 1.1-2.0 {mu}m. Analysis of the light curve gives the most precise estimate yet of the stellar mean density, {rho}{sub *} = 0.497{sup +0.042} {sub -0.057} g cm{sup -3}. By requiring agreement between the observed stellar properties (including {rho}{sub *}) and stellar evolutionary models, we refine the estimate of the stellar radius: R {sub *} = 1.541{sup +0.046} {sub -0.042} R {sub sun}. We also find a deeper transit than has been measured at optical and mid-infrared wavelengths. Taken together, these findings imply a planetary radius of R{sub p} = 0.813{sup +0.027} {sub -0.025} R {sub Jup}, which is larger than earlier estimates. Models of the planetary interior still require a metal-enriched composition, although the required degree of metal enrichment is reduced. It is also possible that the deeper NICMOS transit is caused by wavelength-dependent absorption by constituents in the planet's atmosphere, although simple model atmospheres do not predict this effect to be strong enough to account for the discrepancy. We use the four newly measured transit times to compute a refined transit ephemeris.

  10. New 2MASS near-infrared photometry for globular clusters in M31

    SciTech Connect

    Wang, Song; Ma, Jun; Wu, Zhenyu; Zhou, Xu

    2014-07-01

    We present Two Micron All Sky Survey JHK {sub s} photometry for 913 star clusters and candidates in the field of M31, which are selected from the latest Revised Bologna Catalog of M31 globular clusters (GCs) and candidates. The photometric measurements in this paper supplement this catalog, and provide the most comprehensive and homogeneous photometric catalog for M31 GCs in the JHK {sub s} bandpasses. In general, our photometry is consistent with previous measurements. The globular cluster luminosity function (GCLF) peaks for the confirmed GCs derived by fitting a t {sub 5} distribution using the maximum likelihood method are J{sub 0}=15.348{sub −0.208}{sup +0.206}, H{sub 0}=14.703{sub −0.180}{sup +0.176}, and K{sub s0}=14.534{sub −0.146}{sup +0.142}, all of which agree well with previous studies. The GCLFs are different between metal-rich (MR) and metal-poor (MP), and between inner and outer subpopulations, as MP clusters are fainter than their MR counterparts and the inner clusters are brighter than the outer ones, which confirm previous results. The NIR colors of the GC candidates are on average redder than those of the confirmed GCs, which leads to an obscure bimodal distribution of color indices. The relation of (V – K {sub s}){sub 0} and metallicity shows a notable departure from linearity, with a shallower slope toward the redder end. The color-magnitude diagram (CMD) and color-color diagram show that many GC candidates are located out of the evolutionary tracks, suggesting that some of them may be false M31 GC candidates. The CMD also shows that the initial mass function of M31 GCs covers a large range, and the majority of the clusters have initial masses between 10{sup 3} and 10{sup 6} M {sub ☉}.

  11. The Araucaria Project. A Distance Determination to the Local Group Spiral M33 from Near-infrared Photometry of Cepheid Variables

    NASA Astrophysics Data System (ADS)

    Gieren, Wolfgang; Górski, Marek; Pietrzyński, Grzegorz; Konorski, Piotr; Suchomska, Ksenia; Graczyk, Dariusz; Pilecki, Bogumil; Bresolin, Fabio; Kudritzki, Rolf-Peter; Storm, Jesper; Karczmarek, Paulina; Gallenne, Alexandre; Calderón, Paula; Geisler, Doug

    2013-08-01

    Motivated by an amazing range of reported distances to the nearby Local Group spiral galaxy M33, we have obtained deep near-infrared photometry for 26 long-period Cepheids in this galaxy with the ESO Very Large Telescope. From the data, we constructed period-luminosity relations in the J and K bands which together with previous optical VI photometry for the Cepheids by Macri et al. were used to determine the true distance modulus of M33, and the mean reddening affecting the Cepheid sample with the multiwavelength fit method developed in the Araucaria Project. We find a true distance modulus of 24.62 for M33, with a total uncertainty of ±0.07 mag which is dominated by the uncertainty on the photometric zero points in our photometry. The reddening is determined as E(B - V) = 0.19 ± 0.02, in agreement with the value used by the Hubble Space Telescope Key Project of Freedman et al. but in some discrepancy with other recent determinations based on blue supergiant spectroscopy and an O-type eclipsing binary which yielded lower reddening values. Our derived M33 distance modulus is extremely insensitive to the adopted reddening law. We show that the possible effects of metallicity and crowding on our present distance determination are both at the 1%-2% level and therefore minor contributors to the total uncertainty of our distance result for M33. Based on observations obtained with the ESO VLT for program 382.D-0469(A).

  12. SEEING THROUGH THE RING: NEAR-INFRARED PHOTOMETRY OF V582 MON (KH 15D)

    SciTech Connect

    Arulanantham, Nicole A.; Herbst, William; Cody, Ann Marie; Stauffer, John R.; Rebull, Luisa M.; Agol, Eric; Windemuth, Diana; Marengo, Massimo; Winn, Joshua N.; Hamilton, Catrina M.; Mundt, Reinhard; Johns-Krull, Christopher M.; Gutermuth, Robert A.

    2016-04-15

    We examine the light and color evolution of the T Tauri binary KH 15D through photometry obtained at wavelengths between 0.55 and 8.0 μm. The data were collected with A Novel Dual Imaging CAMera (ANDICAM) on the 1.3 m SMARTS telescope at Cerro-Tololo Inter-American Observatory and with InfraRed Array Camera on the Spitzer Space Telescope. We show that the system’s circumbinary ring, which acts as a screen that covers and uncovers different portions of the binary orbit as the ring precesses, has reached an orientation where the brighter component (star B) fully or nearly fully emerges during each orbital cycle. The fainter component (star A) remains fully occulted by the screen at all phases. The leading and trailing edges of the screen move across the sky at the same rate of ∼15 m s{sup −1}, consistent with expectation for a ring with a radius and width of ∼4 au and a precession period of ∼6500 years. Light and color variations continue to indicate that the screen is sharp edged and opaque at VRIJH wavelengths. However, we find an increasing transparency of the ring edge at 2.2, 3.6, and 4.5 μm. Reddening seen at the beginning of the eclipse that occurred during the CSI 2264 campaign particularly suggests selective extinction by a population of large dust grains. Meanwhile, the gradual bluing observed while star B is setting is indicative of forward scattering effects at the edge of the ring. The spectral energy distribution of the system at its bright phase shows no evidence of infrared excess emission that can be attributed to radiation from the ring or other dust component out to 8 μm.

  13. Near-infrared photometry of globular clusters towards the Galactic bulge: observations and photometric metallicity indicators

    NASA Astrophysics Data System (ADS)

    Cohen, Roger E.; Moni Bidin, Christian; Mauro, Francesco; Bonatto, Charles; Geisler, Douglas

    2017-01-01

    We present wide-field JHKS photometry of 16 Galactic globular clusters located towards the Galactic bulge, calibrated on the Two Micron All-Sky Survey photometric system. Differential reddening corrections and statistical field star decontamination are employed for all of these clusters before fitting fiducial sequences to the cluster red giant branches (RGBs). Observed values and uncertainties are reported for several photometric features, including the magnitude of the RGB bump, tip, the horizontal branch (HB) and the slope of the upper RGB. The latest spectroscopically determined chemical abundances are used to build distance- and reddening-independent relations between observed photometric features and cluster metallicity, optimizing the sample size and metallicity baseline of these relations by supplementing our sample with results from the literature. We find that the magnitude difference between the HB and the RGB bump can be used to predict metallicities, in terms of both iron abundance [Fe/H] and global metallicity [M/H], with a precision of better than 0.1 dex in all three near-IR bandpasses for relatively metal-rich ([M/H] ≳ -1) clusters. Meanwhile, both the slope of the upper RGB and the magnitude difference between the RGB tip and bump are useful metallicity indicators over the entire sampled metallicity range (-2 ≲ [M/H] ≲ 0) with a precision of 0.2 dex or better, despite model predictions that the RGB slope may become unreliable at high (near-solar) metallicities. Our results agree with previous calibrations in light of the relevant uncertainties, and we discuss implications for clusters with controversial metallicities as well as directions for further investigation.

  14. Seeing Through the Ring: Near-infrared Photometry of V582 Mon (KH 15D)

    NASA Astrophysics Data System (ADS)

    Arulanantham, Nicole A.; Herbst, William; Cody, Ann Marie; Stauffer, John R.; Rebull, Luisa M.; Agol, Eric; Windemuth, Diana; Marengo, Massimo; Winn, Joshua N.; Hamilton, Catrina M.; Mundt, Reinhard; Johns-Krull, Christopher M.; Gutermuth, Robert A.

    2016-04-01

    We examine the light and color evolution of the T Tauri binary KH 15D through photometry obtained at wavelengths between 0.55 and 8.0 μm. The data were collected with A Novel Dual Imaging CAMera (ANDICAM) on the 1.3 m SMARTS telescope at Cerro-Tololo Inter-American Observatory and with InfraRed Array Camera on the Spitzer Space Telescope. We show that the system’s circumbinary ring, which acts as a screen that covers and uncovers different portions of the binary orbit as the ring precesses, has reached an orientation where the brighter component (star B) fully or nearly fully emerges during each orbital cycle. The fainter component (star A) remains fully occulted by the screen at all phases. The leading and trailing edges of the screen move across the sky at the same rate of ˜15 m s-1, consistent with expectation for a ring with a radius and width of ˜4 au and a precession period of ˜6500 years. Light and color variations continue to indicate that the screen is sharp edged and opaque at VRIJH wavelengths. However, we find an increasing transparency of the ring edge at 2.2, 3.6, and 4.5 μm. Reddening seen at the beginning of the eclipse that occurred during the CSI 2264 campaign particularly suggests selective extinction by a population of large dust grains. Meanwhile, the gradual bluing observed while star B is setting is indicative of forward scattering effects at the edge of the ring. The spectral energy distribution of the system at its bright phase shows no evidence of infrared excess emission that can be attributed to radiation from the ring or other dust component out to 8 μm.

  15. Near-Infrared Photometry and Spectroscopy of L and T Dwarfs: The Effects of Temperature, Clouds, and Gravity

    NASA Astrophysics Data System (ADS)

    Knapp, G. R.; Leggett, S. K.; Fan, X.; Marley, M. S.; Geballe, T. R.; Golimowski, D. A.; Finkbeiner, D.; Gunn, J. E.; Hennawi, J.; Ivezić, Z.; Lupton, R. H.; Schlegel, D. J.; Strauss, M. A.; Tsvetanov, Z. I.; Chiu, K.; Hoversten, E. A.; Glazebrook, K.; Zheng, W.; Hendrickson, M.; Williams, C. C.; Uomoto, A.; Vrba, F. J.; Henden, A. A.; Luginbuhl, C. B.; Guetter, H. H.; Munn, J. A.; Canzian, B.; Schneider, Donald P.; Brinkmann, J.

    2004-06-01

    We present new JHK photometry on the MKO-NIR system and JHK spectroscopy for a large sample of L and T dwarfs. Photometry has been obtained for 71 dwarfs, and spectroscopy for 56. The sample comprises newly identified very red objects from the Sloan Digital Sky Survey (SDSS) and known dwarfs from the SDSS and the Two Micron All Sky Survey (2MASS). Spectral classification has been carried out using four previously defined indices from Geballe et al. that measure the strengths of the near infrared water and methane bands. We identify nine new L8-9.5 dwarfs and 14 new T dwarfs from SDSS, including the latest yet found by SDSS, the T7 dwarf SDSS J175805.46+463311.9. We classify 2MASS J04151954-0935066 as T9, the latest and coolest dwarf found to date. We combine the new results with our previously published data to produce a sample of 59 L dwarfs and 42 T dwarfs with imaging data on a single photometric system and with uniform spectroscopic classification. We compare the near-infrared colors and absolute magnitudes of brown dwarfs near the L-T transition with predictions made by models of the distribution and evolution of photospheric condensates. There is some scatter in the Geballe et al. spectral indices for L dwarfs, suggesting that these indices are probing different levels of the atmosphere and are affected by the location of the condensate cloud layer. The near-infrared colors of the L dwarfs also show scatter within a given spectral type, which is likely due to variations in the altitudes, spatial distributions, and thicknesses of the clouds. We have identified a small group of late-L dwarfs that are relatively blue for their spectral type and that have enhanced FeH, H2O, and K I absorption, possibly due to an unusually small amount of condensates. The scatter seen in the H-K color for late-T dwarfs can be reproduced by models with a range in surface gravity. The variation is probably due to the effect on the K-band flux of pressure-induced H2 opacity. The

  16. CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey

    NASA Astrophysics Data System (ADS)

    Grogin, Norman A.; Kocevski, Dale D.; Faber, S. M.; Ferguson, Henry C.; Koekemoer, Anton M.; Riess, Adam G.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frédéric; Brown, Thomas M.; Caputi, Karina I.; Casertano, Stefano; Cassata, Paolo; Castellano, Marco; Challis, Peter; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J.; Roshan Cooray, Asantha; Croton, Darren J.; Daddi, Emanuele; Dahlen, Tomas; Davé, Romeel; de Mello, Duília F.; Dekel, Avishai; Dickinson, Mark; Dolch, Timothy; Donley, Jennifer L.; Dunlop, James S.; Dutton, Aaron A.; Elbaz, David; Fazio, Giovanni G.; Filippenko, Alexei V.; Finkelstein, Steven L.; Fontana, Adriano; Gardner, Jonathan P.; Garnavich, Peter M.; Gawiser, Eric; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P.; Häussler, Boris; Hopkins, Philip F.; Huang, Jia-Sheng; Huang, Kuang-Han; Jha, Saurabh W.; Kartaltepe, Jeyhan S.; Kirshner, Robert P.; Koo, David C.; Lai, Kamson; Lee, Kyoung-Soo; Li, Weidong; Lotz, Jennifer M.; Lucas, Ray A.; Madau, Piero; McCarthy, Patrick J.; McGrath, Elizabeth J.; McIntosh, Daniel H.; McLure, Ross J.; Mobasher, Bahram; Moustakas, Leonidas A.; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A.; Niemi, Sami-Matias; Noeske, Kai G.; Papovich, Casey J.; Pentericci, Laura; Pope, Alexandra; Primack, Joel R.; Rajan, Abhijith; Ravindranath, Swara; Reddy, Naveen A.; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R.; Rodney, Steven A.; Rosario, David J.; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Somerville, Rachel S.; Spinrad, Hyron; Straughn, Amber N.; Strolger, Louis-Gregory; Telford, Olivia; Teplitz, Harry I.; Trump, Jonathan R.; van der Wel, Arjen; Villforth, Carolin; Wechsler, Risa H.; Weiner, Benjamin J.; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yan, Hao-Jing; Yun, Min S.

    2011-12-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, over the approximate redshift (z) range 8-1.5. It will image >250,000 distant galaxies using three separate cameras on the Hubble Space Telescope, from the mid-ultraviolet to the near-infrared, and will find and measure Type Ia supernovae at z > 1.5 to test their accuracy as standardizable candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 109 M ⊙ to z ≈ 2, reaching the knee of the ultraviolet luminosity function of galaxies to z ≈ 8. The survey covers approximately 800 arcmin2 and is divided into two parts. The CANDELS/Deep survey (5σ point-source limit H = 27.7 mag) covers ~125 arcmin2 within Great Observatories Origins Deep Survey (GOODS)-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-deep Survey) and covers the full area to a 5σ point-source limit of H >~ 27.0 mag. Together with the Hubble Ultra Deep Fields, the strategy creates a three-tiered "wedding-cake" approach that has proven efficient for extragalactic surveys. Data from the survey are nonproprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design. The Hubble data processing and products are described in a companion paper.

  17. CANDELS: THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY

    SciTech Connect

    Grogin, Norman A.; Ferguson, Henry C.; Koekemoer, Anton M.; Brown, Thomas M.; Casertano, Stefano; Kocevski, Dale D.; Faber, S. M.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Cassata, Paolo; Castellano, Marco; Challis, Peter; Chary, Ranga-Ram; and others

    2011-12-01

    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, over the approximate redshift (z) range 8-1.5. It will image >250,000 distant galaxies using three separate cameras on the Hubble Space Telescope, from the mid-ultraviolet to the near-infrared, and will find and measure Type Ia supernovae at z > 1.5 to test their accuracy as standardizable candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 10{sup 9} M{sub Sun} to z Almost-Equal-To 2, reaching the knee of the ultraviolet luminosity function of galaxies to z Almost-Equal-To 8. The survey covers approximately 800 arcmin{sup 2} and is divided into two parts. The CANDELS/Deep survey (5{sigma} point-source limit H = 27.7 mag) covers {approx}125 arcmin{sup 2} within Great Observatories Origins Deep Survey (GOODS)-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-deep Survey) and covers the full area to a 5{sigma} point-source limit of H {approx}> 27.0 mag. Together with the Hubble Ultra Deep Fields, the strategy creates a three-tiered 'wedding-cake' approach that has proven efficient for extragalactic surveys. Data from the survey are nonproprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design. The Hubble data processing and products are described in a companion paper.

  18. THE HIGH A{sub V} Quasar Survey: Reddened Quasi-Stellar Objects selected from optical/near-infrared photometry. II

    SciTech Connect

    Krogager, J.-K.; Fynbo, J. P. U.; Vestergaard, M.; Geier, S.; Venemans, B. P.; Ledoux, C.; Møller, P.; Noterdaeme, P.; Kangas, T.; Pursimo, T.; Smirnova, O.; Saturni, F. G.

    2015-03-15

    Quasi-stellar objects (QSOs) whose spectral energy distributions (SEDs) are reddened by dust either in their host galaxies or in intervening absorber galaxies are to a large degree missed by optical color selection criteria like the ones used by the Sloan Digital Sky Survey (SDSS). To overcome this bias against red QSOs, we employ a combined optical and near-infrared (near-IR) color selection. In this paper, we present a spectroscopic follow-up campaign of a sample of red candidate QSOs which were selected from the SDSS and the UKIRT Infrared Deep Sky Survey (UKIDSS). The spectroscopic data and SDSS/UKIDSS photometry are supplemented by mid-infrared photometry from the Wide-field Infrared Survey Explorer. In our sample of 159 candidates, 154 (97%) are confirmed to be QSOs. We use a statistical algorithm to identify sightlines with plausible intervening absorption systems and identify nine such cases assuming dust in the absorber similar to Large Magellanic Cloud sightlines. We find absorption systems toward 30 QSOs, 2 of which are consistent with the best-fit absorber redshift from the statistical modeling. Furthermore, we observe a broad range in SED properties of the QSOs as probed by the rest-frame 2 μm flux. We find QSOs with a strong excess as well as QSOs with a large deficit at rest-frame 2 μm relative to a QSO template. Potential solutions to these discrepancies are discussed. Overall, our study demonstrates the high efficiency of the optical/near-IR selection of red QSOs.

  19. UVUDF: Ultraviolet Through Near-infrared Catalog and Photometric Redshifts of Galaxies in the Hubble Ultra Deep Field

    NASA Astrophysics Data System (ADS)

    Rafelski, Marc; Teplitz, Harry I.; Gardner, Jonathan P.; Coe, Dan; Bond, Nicholas A.; Koekemoer, Anton M.; Grogin, Norman; Kurczynski, Peter; McGrath, Elizabeth J.; Bourque, Matthew; Atek, Hakim; Brown, Thomas M.; Colbert, James W.; Codoreanu, Alex; Ferguson, Henry C.; Finkelstein, Steven L.; Gawiser, Eric; Giavalisco, Mauro; Gronwall, Caryl; Hanish, Daniel J.; Lee, Kyoung-Soo; Mehta, Vihang; de Mello, Duilia F.; Ravindranath, Swara; Ryan, Russell E.; Scarlata, Claudia; Siana, Brian; Soto, Emmaris; Voyer, Elysse N.

    2015-07-01

    We present photometry and derived redshifts from up to eleven bandpasses for 9927 galaxies in the Hubble Ultra Deep field (UDF), covering an observed wavelength range from the near-ultraviolet (NUV) to the near-infrared (NIR) with Hubble Space Telescope observations. Our Wide Field Camera 3 (WFC3)/UV F225W, F275W, and F336W image mosaics from the ultra-violet UDF (UVUDF) imaging campaign are newly calibrated to correct for charge transfer inefficiency, and use new dark calibrations to minimize background gradients and pattern noise. Our NIR WFC3/IR image mosaics combine the imaging from the UDF09 and UDF12 campaigns with CANDELS data to provide NIR coverage for the entire UDF field of view. We use aperture-matched point-spread function corrected photometry to measure photometric redshifts in the UDF, sampling both the Lyman break and Balmer break of galaxies at z˜ 0.8-3.4, and one of the breaks over the rest of the redshift range. Our comparison of these results with a compilation of robust spectroscopic redshifts shows an improvement in the galaxy photometric redshifts by a factor of two in scatter and a factor three in outlier fraction (OLF) over previous UDF catalogs. The inclusion of the new NUV data is responsible for a factor of two decrease in the OLF compared to redshifts determined from only the optical and NIR data, and improves the scatter at z\\lt 0.5 and at z\\gt 2. The panchromatic coverage of the UDF from the NUV through the NIR yields robust photometric redshifts of the UDF, with the lowest OLF available.

  20. Fully reflective deep ultraviolet to near infrared spectrometer and entrance optics for resonance Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Schulz, B.; Bäckström, J.; Budelmann, D.; Maeser, R.; Rübhausen, M.; Klein, M. V.; Schoeffel, E.; Mihill, A.; Yoon, S.

    2005-07-01

    We present the design and performance of a new triple-grating deep ultraviolet to near-infrared spectrometer. The system is fully achromatic due to the use of reflective optics. The minimization of image aberrations by using on- and off- axis parabolic mirrors as well as elliptical mirrors yields a strong stray light rejection with high resolution over a wavelength range between 165 and 1000nm. The Raman signal is collected with a reflective entrance objective with a numerical aperture of 0.5, featuring a Cassegrain-type design. Resonance Raman studies on semiconductors and on correlated compounds, such as LaMnO3, highlight the performance of this instrument, and show diverse resonance effects between 1.96 and 5.4eV.

  1. Transmission in near-infrared optical windows for deep brain imaging.

    PubMed

    Shi, Lingyan; Sordillo, Laura A; Rodríguez-Contreras, Adrián; Alfano, Robert

    2016-01-01

    Near-infrared (NIR) radiation has been employed using one- and two-photon excitation of fluorescence imaging at wavelengths 650-950 nm (optical window I) for deep brain imaging; however, longer wavelengths in NIR have been overlooked due to a lack of suitable NIR-low band gap semiconductor imaging detectors and/or femtosecond laser sources. This research introduces three new optical windows in NIR and demonstrates their potential for deep brain tissue imaging. The transmittances are measured in rat brain tissue in the second (II, 1,100-1,350 nm), third (III, 1,600-1,870 nm), and fourth (IV, centered at 2,200 nm) NIR optical tissue windows. The relationship between transmission and tissue thickness is measured and compared with the theory. Due to a reduction in scattering and minimal absorption, window III is shown to be the best for deep brain imaging, and windows II and IV show similar but better potential for deep imaging than window I.

  2. Inferring deep-brain activity from cortical activity using functional near-infrared spectroscopy.

    PubMed

    Liu, Ning; Cui, Xu; Bryant, Daniel M; Glover, Gary H; Reiss, Allan L

    2015-03-01

    Functional near-infrared spectroscopy (fNIRS) is an increasingly popular technology for studying brain function because it is non-invasive, non-irradiating and relatively inexpensive. Further, fNIRS potentially allows measurement of hemodynamic activity with high temporal resolution (milliseconds) and in naturalistic settings. However, in comparison with other imaging modalities, namely fMRI, fNIRS has a significant drawback: limited sensitivity to hemodynamic changes in deep-brain regions. To overcome this limitation, we developed a computational method to infer deep-brain activity using fNIRS measurements of cortical activity. Using simultaneous fNIRS and fMRI, we measured brain activity in 17 participants as they completed three cognitive tasks. A support vector regression (SVR) learning algorithm was used to predict activity in twelve deep-brain regions using information from surface fNIRS measurements. We compared these predictions against actual fMRI-measured activity using Pearson's correlation to quantify prediction performance. To provide a benchmark for comparison, we also used fMRI measurements of cortical activity to infer deep-brain activity. When using fMRI-measured activity from the entire cortex, we were able to predict deep-brain activity in the fusiform cortex with an average correlation coefficient of 0.80 and in all deep-brain regions with an average correlation coefficient of 0.67. The top 15% of predictions using fNIRS signal achieved an accuracy of 0.7. To our knowledge, this study is the first to investigate the feasibility of using cortical activity to infer deep-brain activity. This new method has the potential to extend fNIRS applications in cognitive and clinical neuroscience research.

  3. THE TAIWAN ECDFS NEAR-INFRARED SURVEY: ULTRA-DEEP J AND K{sub S} IMAGING IN THE EXTENDED CHANDRA DEEP FIELD-SOUTH

    SciTech Connect

    Hsieh, Bau-Ching; Wang, Wei-Hao; Hsieh, Chih-Chiang; Lin, Lihwai; Lim, Jeremy; Ho, Paul T. P.; Yan Haojing

    2012-12-15

    We present ultra-deep J and K{sub S} imaging observations covering a 30' Multiplication-Sign 30' area of the Extended Chandra Deep Field-South (ECDFS) carried out by our Taiwan ECDFS Near-Infrared Survey (TENIS). The median 5{sigma} limiting magnitudes for all detected objects in the ECDFS reach 24.5 and 23.9 mag (AB) for J and K{sub S} , respectively. In the inner 400 arcmin{sup 2} region where the sensitivity is more uniform, objects as faint as 25.6 and 25.0 mag are detected at 5{sigma}. Thus, this is by far the deepest J and K{sub S} data sets available for the ECDFS. To combine TENIS with the Spitzer IRAC data for obtaining better spectral energy distributions of high-redshift objects, we developed a novel deconvolution technique (IRACLEAN) to accurately estimate the IRAC fluxes. IRACLEAN can minimize the effect of blending in the IRAC images caused by the large point-spread functions and reduce the confusion noise. We applied IRACLEAN to the images from the Spitzer IRAC/MUSYC Public Legacy in the ECDFS survey (SIMPLE) and generated a J+K{sub S} -selected multi-wavelength catalog including the photometry of both the TENIS near-infrared and the SIMPLE IRAC data. We publicly release the data products derived from this work, including the J and K{sub S} images and the J+K{sub S} -selected multi-wavelength catalog.

  4. A luciferin analogue generating near-infrared bioluminescence achieves highly sensitive deep-tissue imaging

    PubMed Central

    Kuchimaru, Takahiro; Iwano, Satoshi; Kiyama, Masahiro; Mitsumata, Shun; Kadonosono, Tetsuya; Niwa, Haruki; Maki, Shojiro; Kizaka-Kondoh, Shinae

    2016-01-01

    In preclinical cancer research, bioluminescence imaging with firefly luciferase and D-luciferin has become a standard to monitor biological processes both in vitro and in vivo. However, the emission maximum (λmax) of bioluminescence produced by D-luciferin is 562 nm where light is not highly penetrable in biological tissues. This emphasizes a need for developing a red-shifted bioluminescence imaging system to improve detection sensitivity of targets in deep tissue. Here we characterize the bioluminescent properties of the newly synthesized luciferin analogue, AkaLumine-HCl. The bioluminescence produced by AkaLumine-HCl in reactions with native firefly luciferase is in the near-infrared wavelength ranges (λmax=677 nm), and yields significantly increased target-detection sensitivity from deep tissues with maximal signals attained at very low concentrations, as compared with D-luciferin and emerging synthetic luciferin CycLuc1. These characteristics offer a more sensitive and accurate method for non-invasive bioluminescence imaging with native firefly luciferase in various animal models. PMID:27297211

  5. A luciferin analogue generating near-infrared bioluminescence achieves highly sensitive deep-tissue imaging.

    PubMed

    Kuchimaru, Takahiro; Iwano, Satoshi; Kiyama, Masahiro; Mitsumata, Shun; Kadonosono, Tetsuya; Niwa, Haruki; Maki, Shojiro; Kizaka-Kondoh, Shinae

    2016-06-14

    In preclinical cancer research, bioluminescence imaging with firefly luciferase and D-luciferin has become a standard to monitor biological processes both in vitro and in vivo. However, the emission maximum (λmax) of bioluminescence produced by D-luciferin is 562 nm where light is not highly penetrable in biological tissues. This emphasizes a need for developing a red-shifted bioluminescence imaging system to improve detection sensitivity of targets in deep tissue. Here we characterize the bioluminescent properties of the newly synthesized luciferin analogue, AkaLumine-HCl. The bioluminescence produced by AkaLumine-HCl in reactions with native firefly luciferase is in the near-infrared wavelength ranges (λmax=677 nm), and yields significantly increased target-detection sensitivity from deep tissues with maximal signals attained at very low concentrations, as compared with D-luciferin and emerging synthetic luciferin CycLuc1. These characteristics offer a more sensitive and accurate method for non-invasive bioluminescence imaging with native firefly luciferase in various animal models.

  6. Hemodynamic measurements in deep brain tissues of humans by near-infrared time-resolved spectroscopy

    NASA Astrophysics Data System (ADS)

    Suzuki, Hiroaki; Oda, Motoki; Yamaki, Etsuko; Suzuki, Toshihiko; Yamashita, Daisuke; Yoshimoto, Kenji; Homma, Shu; Yamashita, Yutaka

    2014-03-01

    Using near-infrared time-resolved spectroscopy (TRS), we measured the human head in transmittance mode to obtain the optical properties, tissue oxygenation, and hemodynamics of deep brain tissues in 50 healthy adult volunteers. The right ear canal was irradiated with 3-wavelengths of pulsed light (760, 795, and 835nm), and the photons passing through the human head were collected at the left ear canal. Optical signals with sufficient intensity could be obtained from 46 of the 50 volunteers. By analyzing the temporal profiles based on the photon diffusion theory, we successfully obtained absorption coefficients for each wavelength. The levels of oxygenated hemoglobin (HbO2), deoxygenated hemoglobin (Hb), total hemoglobin (tHb), and tissue oxygen saturation (SO2) were then determined by referring to the hemoglobin spectroscopic data. Compared with the SO2 values for the forehead measurements in reflectance mode, the SO2 values of the transmittance measurements of the human head were approximately 10% lower, and tHb values of the transmittance measurements were always lower than those of the forehead reflectance measurements. Moreover, the level of hemoglobin and the SO2 were strongly correlated between the human head measurements in transmittance mode and the forehead measurements in the reflectance mode, respectively. These results demonstrated a potential application of this TRS system in examining deep brain tissues of humans.

  7. DEEP NEAR-INFRARED SURVEY OF THE PIPE NEBULA. II. DATA, METHODS, AND DUST EXTINCTION MAPS

    SciTech Connect

    Roman-Zuniga, Carlos G.; Lada, Charles J.; Lombardi, Marco

    2010-12-20

    We present a new set of high-resolution dust extinction maps of the nearby and essentially starless Pipe Nebula molecular cloud. The maps were constructed from a concerted deep near-infrared imaging survey with the ESO-VLT, ESO-NTT, CAHA 3.5 m telescopes, and 2MASS data. The new maps have a resolution three times higher than the previous extinction map of this cloud by Lombardi et al. and are able to resolve structures down to 2600 AU. We detect 244 significant extinction peaks across the cloud. These peaks have masses between 0.1 and 18.4 M{sub sun}, diameters between 1.2 and 5.7 x 10{sup 4} AU (0.06 and 0.28 pc), and mean densities of about 10{sup 4} cm{sup -3}, all in good agreement with previous results. From the analysis of the mean surface density of companions we find a well-defined scale near 1.4 x 10{sup 4} AU below which we detect a significant decrease in structure of the cloud. This scale is smaller than the Jeans length calculated from the mean density of the peaks. The surface density of peaks is not uniform but instead it displays clustering. Extinction peaks in the Pipe Nebula appear to have a spatial distribution similar to the stars in Taurus, suggesting that the spatial distribution of stars evolves directly from the primordial spatial distribution of high-density material.

  8. Deep optical imaging of tissue using the second and third near-infrared spectral windows.

    PubMed

    Sordillo, Laura A; Pu, Yang; Pratavieira, Sebastião; Budansky, Yury; Alfano, Robert R

    2014-05-01

    Light at wavelengths in the near-infrared (NIR) region allows for deep penetration and minimal absorption through high scattering tissue media. NIR light has been conventionally used through the first NIR optical tissue window with wavelengths from 650 to 950 nm. Longer NIR wavelengths had been overlooked due to major water absorption peaks and a lack of NIR-CCD detectors. The second NIR spectral window from 1100 to 1350 nm and a new spectral window from 1600 to 1870 nm, known as the third NIR optical window, were investigated. Optical attenuation measurements from thin tissue slices of normal and malignant breast and prostate tissues, pig brain, and chicken tissue were obtained in the spectral range from 400 to 2500 nm. Optical images of chicken tissue overlying three black wires were also obtained using the second and third spectral windows. Due to a reduction in scattering and minimal absorption, longer attenuation lengths and clearer optical images could be seen in the second and third NIR optical windows compared to the conventional first NIR optical window. A possible fourth optical window centered at 2200 nm was noted.

  9. A COMPARISON OF NEAR-INFRARED PHOTOMETRY AND SPECTRA FOR Y DWARFS WITH A NEW GENERATION OF COOL CLOUDY MODELS

    SciTech Connect

    Leggett, S. K.; Morley, Caroline V.; Fortney, Jonathan J.; Marley, M. S.; Saumon, D.; Visscher, Channon

    2013-02-15

    We present YJHK photometry, or a subset, for the six Y dwarfs discovered in Wide-field Infrared Survey Explorer (WISE) data by Cushing et al. The data were obtained using the Near-Infrared Imager on the Gemini North telescope; YJHK were obtained for WISEP J041022.71+150248.5, WISEP J173835.52+273258.9, and WISEPC J205628.90+145953.3; YJH for WISEPC J140518.40+553421.5 and WISEP J154151.65225025.2; and YJK for WISEP J182831.08+265037.8. We also present a far-red spectrum obtained using GMOS-North for WISEPC J205628.90+145953.3. We compare the data to Morley et al. models, which include cloud decks of sulfide and chloride condensates. We find that the models with these previously neglected clouds can reproduce the energy distributions of T9 to Y0 dwarfs quite well, other than near 5 {mu}m where the models are too bright. This is thought to be because the models do not include departures from chemical equilibrium caused by vertical mixing, which would enhance the abundance of CO and CO{sub 2}, decreasing the flux at 5 {mu}m. Vertical mixing also decreases the abundance of NH{sub 3}, which would otherwise have strong absorption features at 1.03 {mu}m and 1.52 {mu}m that are not seen in the Y0 WISEPC J205628.90+145953.3. We find that the five Y0 to Y0.5 dwarfs have 300 {approx}< T {sub eff} K {approx}< 450, 4.0 {approx}< log g {approx}< 4.5, and f {sub sed} Almost-Equal-To 3. These temperatures and gravities imply a mass range of 5-15 M {sub Jupiter} and ages around 5 Gyr. We suggest that WISEP J182831.08+265037.8 is a binary system, as this better explains its luminosity and color. We find that the data can be made consistent with observed trends, and generally consistent with the models, if the system is composed of a T {sub eff} Almost-Equal-To 325 K and log g {approx}< 4.5 primary, and a T {sub eff} Almost-Equal-To 300 K and log g {approx}> 4.0 secondary, corresponding to masses of 10 and 7 M {sub Jupiter} and an age around 2 Gyr. If our deconvolution is correct

  10. Deep wide-field near-infrared survey of the Carina Nebula

    NASA Astrophysics Data System (ADS)

    Preibisch, T.; Ratzka, T.; Kuderna, B.; Ohlendorf, H.; King, R. R.; Hodgkin, S.; Irwin, M.; Lewis, J. R.; McCaughrean, M. J.; Zinnecker, H.

    2011-06-01

    Context. The Great Nebula in Carina is a giant H ii region and a superb location in which to study the physics of violent massive star formation, but the population of the young low-mass stars remained very poorly studied until recently. Aims: Our aim was to produce a near-infrared survey that is deep enough to detect the full low-mass stellar population (i.e. down to ≈0.1 M⊙ and for extinctions up to AV ≈ 15 mag) and wide enough to cover all important parts of the Carina Nebula complex (CNC), including the clusters Tr 14, 15, and 16 as well as the South Pillars region. Methods: We used HAWK-I at the ESO VLT to survey the central ≈0.36 deg2 area of the Carina Nebula. These data reveal more than 600 000 individual infrared sources down to magnitudes as faint as J ≈ 23, H ≈ 22, and Ks ≈ 21. The results of a recent deep X-ray survey (which is complete down to stellar masses of ~0.5-1 M⊙) are used to distinguish between young stars in Carina and background contaminants. We analyze color - magnitude diagrams (CMDs) to derive information about the ages and masses of the low-mass stars. Results: The ages of the low-mass stars agree with previous age estimates for the massive stars. The CMD suggests that ≈3200 of the X-ray selected stars have masses of M∗ ≥ 1 M⊙; this number is in good agreement with extrapolations of the field IMF based on the number of high-mass (M∗ ≥ 20 M⊙) stars and shows that there is no deficit of low-mass stars in the CNC. The HAWK-I images confirm that about 50% of all young stars in Carina are in a widely distributed, non-clustered spatial configuration. Narrow-band images reveal six molecular hydrogen emission objects (MHOs) that trace jets from embedded protostars. However, none of the optical HH objects shows molecular hydrogen emission, suggesting that the jet-driving protostars are located very close to the edges of the globules in which they are embedded. Conclusions: The near-infrared excess fractions for the

  11. Ultra-deep GEMINI Near-infrared Observations of the Bulge Globular Cluster NGC 6624.

    NASA Astrophysics Data System (ADS)

    Saracino, S.; Dalessandro, E.; Ferraro, F. R.; Geisler, D.; Mauro, F.; Lanzoni, B.; Origlia, L.; Miocchi, P.; Cohen, R. E.; Villanova, S.; Moni Bidin, C.

    2016-11-01

    We used ultra-deep J and K s images secured with the near-infrared (NIR) GSAOI camera assisted by the multi-conjugate adaptive optics system GeMS at the GEMINI South Telescope in Chile, to obtain a (K s , J - K s ) color-magnitude diagram (CMD) for the bulge globular cluster NGC 6624. We obtained the deepest and most accurate NIR CMD from the ground for this cluster, by reaching K s ˜ 21.5, approximately 8 mag below the horizontal branch level. The entire extension of the Main Sequence (MS) is nicely sampled and at K s ˜ 20 we detected the so-called MS “knee” in a purely NIR CMD. By taking advantage of the exquisite quality of the data, we estimated the absolute age of NGC 6624 (t age = 12.0 ± 0.5 Gyr), which turns out to be in good agreement with previous studies in the literature. We also analyzed the luminosity and mass functions of MS stars down to M ˜ 0.45 M⊙, finding evidence of a significant increase of low-mass stars at increasing distances from the cluster center. This is a clear signature of mass segregation, confirming that NGC 6624 is in an advanced stage of dynamical evolution. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência, Tecnologia e Inovação (Brazil) and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina). Based on observations gathered with ESO-VISTA telescope (program ID 179.B-2002).

  12. Near-infrared resonance-mediated chirp control of a coherently generated broadband deep-ultraviolet spectrum

    SciTech Connect

    Rybak, Leonid; Chuntonov, Lev; Gandman, Andrey; Shakour, Naser; Amitay, Zohar

    2011-09-15

    We investigate the use of shaped near-infrared (NIR) femtosecond pulses to control the generation of coherent broadband deep-ultraviolet (DUV) radiation in an atomic resonance-mediated (2+1) three-photon excitation to a broad far-from-resonance continuum. Previously, we have shown control over the total emitted DUV yield. Here, we experimentally demonstrate phase control over the spectral characteristics (central frequency and bandwidth) of the emitted broadband DUV radiation. It is achieved by tuning the linear chirp applied to the exciting NIR femtosecond pulse. The study is conducted with Na vapor.

  13. Bright near-infrared sources within 1 deg of the Galactic center. I - Survey and 1-20 micron photometry

    NASA Technical Reports Server (NTRS)

    Nagata, Tetsuya; Hyland, A. R.; Straw, S. M.; Sato, Shuji; Kawara, Kimiaki

    1993-01-01

    Results of a near-IR survey of 0.55 sq deg toward the Galactic center are reported. Additional IR photometry of 50 objects found in this survey was made in order to investigate the nature of luminous stars in the central region of the Milky Way including all sources with K less than 7.6 and H-K not less than 1.4. In addition to candidates for normal M-type stars and long-period variables, four objects whose energy spectra peak at about 5 microns have been detected in a small region around (l, b) = (0.15, 0.0 deg), near the crossing of the 6-cm radio arc with the Galactic plane. These four might be young stellar objects near the Galactic center. It is suggested that the relative depth change in the silicate absorption is localized to a fairly small region around the Galactic center.

  14. Deep-red to near-infrared fluorescent dyes: Synthesis, photophysical properties, and application in cell imaging

    NASA Astrophysics Data System (ADS)

    Li, Qi; Liu, Weimin; Wu, Jiasheng; Zhou, Bingjiang; Niu, Guangle; Zhang, Hongyan; Ge, Jiechao; Wang, Pengfei

    2016-07-01

    More and more attention has been paid to the design of new fluorescent imaging agents with good photostability and water solubility, especially those with emissions in the deep-red and near-infrared regions. In this work, we designed and synthesized four novel fluorescent dyes with deep-red or NIR fluorescence by hybridizing coumarin and pyronin moieties based on our previous work. Introduction of carboxylic acid in the dyes not only imparted the dyes with water solubility but also provided a versatile sensing platform for designing the fluorescent probes and sensors of biomolecules. The photophysical properties of these new dyes were investigated through absorption and fluorescence spectroscopy. Cell imaging experiments showed that esterification products could selectively stain lysosomes with good photostability, thereby indicating that they could be useful in the development of fluorescent probes for bioimaging.

  15. Type IIb supernova SN 2011dh: Spectra and photometry from the ultraviolet to the near-infrared

    SciTech Connect

    Marion, G. H.; Kirshner, Robert P.; Foley, Ryan J.; Berlind, Perry; Bieryla, Allyson; Calkins, Michael L.; Challis, Peter; Chornock, Ryan; Esquerdo, Gilbert A.; Falco, Emilio E.; Friedman, Andrew S.; Vinko, Jozsef; Bloom, Joshua S.; Chevalier, Roger A.; Culliton, Chris; Curtis, Jason L.; Everett, Mark E.; France, Kevin; Fransson, Claes; Garnavich, Peter; and others

    2014-02-01

    We report spectroscopic and photometric observations of the Type IIb SN 2011dh obtained between 4 and 34 days after the estimated date of explosion (May 31.5 UT). The data cover a wide wavelength range from 2000 Å in the ultraviolet (UV) to 2.4 μm in the near-infrared (NIR). Optical spectra provide line profiles and velocity measurements of H I, He I, Ca II, and Fe II that trace the composition and kinematics of the supernova (SN). NIR spectra show that helium is present in the atmosphere as early as 11 days after the explosion. A UV spectrum obtained with the Space Telescope Imaging Spectrograph reveals that the UV flux for SN 2011dh is low compared to other SN IIb. Modeling the spectrum with SYNOW suggests that the UV deficit is due to line blanketing from Ti II and Co II. The H I and He I velocities in SN 2011dh are separated by about 4000 km s{sup –1} at all phases. A velocity gap is consistent with models for a preexplosion structure in which a hydrogen-rich shell surrounds the progenitor. We estimate that the H shell of SN 2011dh is ≈8 times less massive than the shell of SN 1993J and ≈3 times more massive than the shell of SN 2008ax. Light curves (LCs) for 12 passbands are presented: UVW2, UVM2, UVW1, U, u', B, V, r', i', J, H, and K{sub s} . In the B band, SN 2011dh reached peak brightness of 13.17 mag at 20.0 ± 0.5 after the explosion. The maximum bolometric luminosity of 1.8 ± 0.2 × 10{sup 42} erg s{sup –1} occurred ≈22 days after the explosion. NIR emission provides more than 30% of the total bolometric flux at the beginning of our observations, and the NIR contribution increases to nearly 50% of the total by day 34. The UV produces 16% of the total flux on day 4, 5% on day 9, and 1% on day 34. We compare the bolometric LCs of SN 2011dh, SN 2008ax, and SN 1993J. The LC are very different for the first 12 days after the explosions, but all three SN IIb display similar peak luminosities, times of peak, decline rates, and colors after maximum

  16. New insights on the formation and assembly of M83 from deep near-infrared imaging

    SciTech Connect

    Barnes, Kate L.; Van Zee, Liese; Dale, Daniel A.; Staudaher, Shawn; Bullock, James S.; Calzetti, Daniela; Chandar, Rupali; Dalcanton, Julianne J.

    2014-07-10

    We present results from new near-infrared (NIR) imaging from the Spitzer Space Telescope that trace the low surface brightness features of the outer disk and stellar stream in the nearby spiral galaxy, M83. Previous observations have shown that M83 hosts a faint stellar stream to the northwest and a star-forming disk that extends to ∼3 times the optical radius (R{sub 25}). By combining the NIR imaging with archival far-ultraviolet (FUV) and H I imaging, we study the star formation history of the system. The NIR surface brightness profile has a break at ∼5.'8 (equivalent to 8.1 kpc and 0.9 R{sub 25}) with a shallower slope beyond this radius, which may result from the recent accretion of gas onto the outer disk and subsequent star formation. Additionally, the ratio of FUV to NIR flux increases with increasing radius in several arms throughout the extended star forming disk, indicating an increase in the ratio of the present to past star formation rate with increasing radius. This sort of inside-out disk formation is consistent with observations of gas infall onto the outer disk of M83. Finally, the flux, size, and shape of the stellar stream are measured and the origin of the stream is explored. The stream has a total NIR flux of 11.6 mJy, which implies a stellar mass of 1 × 10{sup 8} M{sub ☉} in an area subtending ∼80°. No FUV emission is detected in the stream at a level greater than the noise, confirming an intermediate-age or old stellar population in the stream.

  17. Deep ultraviolet to near-infrared emission and photoresponse in layered N-doped graphene quantum dots.

    PubMed

    Tang, Libin; Ji, Rongbin; Li, Xueming; Bai, Gongxun; Liu, Chao Ping; Hao, Jianhua; Lin, Jingyu; Jiang, Hongxing; Teng, Kar Seng; Yang, Zhibin; Lau, Shu Ping

    2014-06-24

    Material that can emit broad spectral wavelengths covering deep ultraviolet, visible, and near-infrared is highly desirable. It can lead to important applications such as broadband modulators, photodetectors, solar cells, bioimaging, and fiber communications. However, there is currently no material that meets such desirable requirement. Here, we report the layered structure of nitrogen-doped graphene quantum dots (N-GQDs) which possess broadband emission ranging from 300 to >1000 nm. The broadband emission is attributed to the layered structure of the N-GQDs that contains a large conjugated system and provides extensive delocalized π electrons. In addition, a broadband photodetector with responsivity as high as 325 V/W is demonstrated by coating N-GQDs onto interdigital gold electrodes. The unusual negative photocurrent is observed which is attributed to the trapping sites induced by the self-passivated surface states in the N-GQDs.

  18. CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey—The Hubble Space Telescope Observations, Imaging Data Products, and Mosaics

    NASA Astrophysics Data System (ADS)

    Koekemoer, Anton M.; Faber, S. M.; Ferguson, Henry C.; Grogin, Norman A.; Kocevski, Dale D.; Koo, David C.; Lai, Kamson; Lotz, Jennifer M.; Lucas, Ray A.; McGrath, Elizabeth J.; Ogaz, Sara; Rajan, Abhijith; Riess, Adam G.; Rodney, Steve A.; Strolger, Louis; Casertano, Stefano; Castellano, Marco; Dahlen, Tomas; Dickinson, Mark; Dolch, Timothy; Fontana, Adriano; Giavalisco, Mauro; Grazian, Andrea; Guo, Yicheng; Hathi, Nimish P.; Huang, Kuang-Han; van der Wel, Arjen; Yan, Hao-Jing; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frédéric; Brown, Thomas M.; Caputi, Karina I.; Cassata, Paolo; Challis, Peter J.; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; Conselice, Christopher J.; Roshan Cooray, Asantha; Croton, Darren J.; Daddi, Emanuele; Davé, Romeel; de Mello, Duilia F.; de Ravel, Loic; Dekel, Avishai; Donley, Jennifer L.; Dunlop, James S.; Dutton, Aaron A.; Elbaz, David; Fazio, Giovanni G.; Filippenko, Alexei V.; Finkelstein, Steven L.; Frazer, Chris; Gardner, Jonathan P.; Garnavich, Peter M.; Gawiser, Eric; Gruetzbauch, Ruth; Hartley, Will G.; Häussler, Boris; Herrington, Jessica; Hopkins, Philip F.; Huang, Jia-Sheng; Jha, Saurabh W.; Johnson, Andrew; Kartaltepe, Jeyhan S.; Khostovan, Ali A.; Kirshner, Robert P.; Lani, Caterina; Lee, Kyoung-Soo; Li, Weidong; Madau, Piero; McCarthy, Patrick J.; McIntosh, Daniel H.; McLure, Ross J.; McPartland, Conor; Mobasher, Bahram; Moreira, Heidi; Mortlock, Alice; Moustakas, Leonidas A.; Mozena, Mark; Nandra, Kirpal; Newman, Jeffrey A.; Nielsen, Jennifer L.; Niemi, Sami; Noeske, Kai G.; Papovich, Casey J.; Pentericci, Laura; Pope, Alexandra; Primack, Joel R.; Ravindranath, Swara; Reddy, Naveen A.; Renzini, Alvio; Rix, Hans-Walter; Robaina, Aday R.; Rosario, David J.; Rosati, Piero; Salimbeni, Sara; Scarlata, Claudia; Siana, Brian; Simard, Luc; Smidt, Joseph; Snyder, Diana; Somerville, Rachel S.; Spinrad, Hyron; Straughn, Amber N.; Telford, Olivia; Teplitz, Harry I.; Trump, Jonathan R.; Vargas, Carlos; Villforth, Carolin; Wagner, Cory R.; Wandro, Pat; Wechsler, Risa H.; Weiner, Benjamin J.; Wiklind, Tommy; Wild, Vivienne; Wilson, Grant; Wuyts, Stijn; Yun, Min S.

    2011-12-01

    This paper describes the Hubble Space Telescope imaging data products and data reduction procedures for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). This survey is designed to document the evolution of galaxies and black holes at z ≈ 1.5-8, and to study Type Ia supernovae at z > 1.5. Five premier multi-wavelength sky regions are selected, each with extensive multi-wavelength observations. The primary CANDELS data consist of imaging obtained in the Wide Field Camera 3 infrared channel (WFC3/IR) and the WFC3 ultraviolet/optical channel, along with the Advanced Camera for Surveys (ACS). The CANDELS/Deep survey covers ~125 arcmin2 within GOODS-N and GOODS-S, while the remainder consists of the CANDELS/Wide survey, achieving a total of ~800 arcmin2 across GOODS and three additional fields (Extended Groth Strip, COSMOS, and Ultra-Deep Survey). We summarize the observational aspects of the survey as motivated by the scientific goals and present a detailed description of the data reduction procedures and products from the survey. Our data reduction methods utilize the most up-to-date calibration files and image combination procedures. We have paid special attention to correcting a range of instrumental effects, including charge transfer efficiency degradation for ACS, removal of electronic bias-striping present in ACS data after Servicing Mission 4, and persistence effects and other artifacts in WFC3/IR. For each field, we release mosaics for individual epochs and eventual mosaics containing data from all epochs combined, to facilitate photometric variability studies and the deepest possible photometry. A more detailed overview of the science goals and observational design of the survey are presented in a companion paper.

  19. Strömgren and near-infrared photometry of metal-rich bulge globular clusters. I. NGC 6528 and its surrounding field

    NASA Astrophysics Data System (ADS)

    Calamida, A.; Bono, G.; Lagioia, E. P.; Milone, A. P.; Fabrizio, M.; Saviane, I.; Moni Bidin, C.; Mauro, F.; Buonanno, R.; Ferraro, I.; Iannicola, G.; Zoccali, M.

    2014-05-01

    We present Strömgren and near-infrared (NIR) photometry of the bulge cluster NGC 6528 and its surrounding field in Baade's Window. uvby images were collected with EFOSC2 on the New Technology Telescope (NTT, La Silla, ESO). The NIR catalogs are based on J,K-band VIRCAM at VISTA (Paranal, ESO) and SOFI at NTT photometry. We matched the aforementioned data sets with Hubble Space Telescope photometry to obtain proper-motion-cleaned samples of NGC 6528 and bulge stars. Furthermore, we were able to correct the Strömgren-NIR photometry for differential reddening. The huge color sensitivity of the Strömgren-NIR color-magnitude-diagrams (CMDs) helped us in separating age and metallicity effects. The red giant branch (RGB) of NGC 6528 is well reproduced in all the CMDs by adopting scaled solar isochrones with solar abundance, that is Z = 0.0198, or α-enhanced isochrones with the same iron content, that is Z = 0.04, and an age range of t = 10-12 Gyr. The same isochrones well reproduce most of the color spread of Baade's Window RGB. These findings support the literature age estimates for NGC 6528. We also performed a new theoretical visual-NIR metallicity calibration based on the Strömgren index m1 and on visual-NIR colors for red giant (RG) stars. Scaled solar and α-enhanced models were adopted and we validated the new metallicity-index-color (MIC) relations by applying them to estimate the photometric metal abundance of a sample of field RGs and of a metal-poor (M 92, [Fe/H] ~-2.3) and a metal-rich (NGC 6624, [Fe/H] ~ -0.7) globular cluster. We applied the calibration to estimate the mean metal abundance of NGC 6528, finding [Fe/H] = [M/H] = -0.04 ± 0.02, with a mean intrinsic dispersion of σ = 0.27 dex, by averaging the metallicities obtained with the scaled solar [m], y - J and [m], y - K MIC relations, and of -0.11 ± 0.01, with σ = 0.27 dex, by using the m1, y - J and m1, y - K relations. These findings support results based on high-resolution spectroscopy

  20. Near Infrared Imaging of the Hubble Deep Field with Keck Telescope

    NASA Technical Reports Server (NTRS)

    Hogg, David W.; Neugebauer, G.; Armus, Lee; Matthews, K.; Pahre, Michael A.; Soifer, B. T.; Weinberger, A. J.

    1997-01-01

    Two deep K-band (2.2 micrometer) images, with point-source detection limits of K=25.2 mag (one sigma), taken with the Keck Telescope in subfields of the Hubble Deep Field, are presented and analyzed. A sample of objects to K=24 mag is constructed and V(sub 606)- I(sub 814) and I(sub 814)-K colors are measured. By stacking visually selected objects, mean I(sub 814)-K colors can be measured to very faint levels, the mean I(sub 814)-K color is constant with apparent magnitude down to V(sub 606)=28 mag.

  1. Deep Near-Infrared Surveys and Young Brown Dwarf Populations in Star-Forming Regions

    NASA Astrophysics Data System (ADS)

    Tamura, M.; Naoi, T.; Oasa, Y.; Nakajima, Y.; Nagashima, C.; Nagayama, T.; Baba, D.; Nagata, T.; Sato, S.; Kato, D.; Kurita, M.; Sugitani, K.; Itoh, Y.; Nakaya, H.; Pickles, A.

    2003-06-01

    We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.

  2. CANDELS: The Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey

    NASA Technical Reports Server (NTRS)

    Grogin, Norman A.; Koekemoer, anton M.; Faber, S. M.; Ferguson, Henry C.; Kocevski, Dale D.; Riess, Adam G.; Acquaviva, Viviana; Alexander, David M.; Almaini, Omar; Ashby, Matthew L. N.; Barden, Marco; Bell, Eric F.; Bournaud, Frederic; Brown, Thomas M.; Caputi, Karina I.; Casertano, Stefano; Cassata, Paolo; Challis, Peter; Chary, Ranga-Ram; Cheung, Edmond; Cirasuolo, Michele; DeMello, Duilla; Gardner, Jonathan P.; Straughn, Amber N.

    2011-01-01

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, from z approx. 8 - 1.5. It will image > 250,000 distant galaxies using three separate cameras on the Hubble Space Tele8cope, from the mid-UV to near-IR, and will find and measure Type Ia supernovae beyond z > 1.5 to test their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 10(exp 9) solar mass to z approx. 2, reaching the knee of the UV luminosity function of galaxies to z approx. 8. The survey covers approximately 800 square arc minutes and is divided into two parts. The CANDELS/Deep survey (5(sigma) point-source limit H =27.7mag) covers approx. 125 square arcminutes within GOODS-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (EGS, COSMOS, and UDS) and covers the full area to a 50(sigma) point-source limit of H ? or approx. = 27.0 mag. Together with the Hubble Ultradeep Fields, the strategy creates a three-tiered "wedding cake" approach that has proven efficient for extragalactic surveys. Data from the survey are non-proprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design.

  3. Hubble Deep Field guide star photometry

    NASA Astrophysics Data System (ADS)

    Zwintz, K.; Kuschnig, R.; Weiss, W. W.; Gray, R. O.; Jenkner, H.

    1999-03-01

    Since the advent of asteroseismology as a promising innovative tool for investigating internal stellar structure, numerous attempts to detect solar type oscillations in distant stars have been conducted. The three Fine Guidance Sensors of the Hubble Space Telescope can contribute to asteroseismology, but only after the data have been corrected for systematic effects, the South Atlantic Anomaly and terrestrial stray light being the most important. We have applied these corrections and obtained essentially photon noise-limited photometry for two guide stars used during the Hubble Deep Field program. Ground-based spectral classification has revealed that the brighter of the two guide stars is a solar-type star with a spectral type of G2mG0iv. Fine Guidance Sensor photometry for this star gives a noise level in the amplitude spectrum of only 23 ppm, which makes it a good candidate for detecting stochastically driven oscillations. We compare our result with theoretical predictions. The second guide star was classified as K1v and therefore is not a candidate for solar type oscillations. Based on observations made with the NASA/ESA {\\it Hubble Space Telescope}, obtained from the data archive at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.

  4. The SXDF-ALMA 2-arcmin2 Deep Survey: Stacking Rest-frame Near-infrared Selected Objects

    NASA Astrophysics Data System (ADS)

    Wang, Wei-Hao; Kohno, Kotaro; Hatsukade, Bunyo; Umehata, Hideki; Aretxaga, Itziar; Hughes, David; Caputi, Karina I.; Dunlop, James S.; Ikarashi, Soh; Iono, Daisuke; Ivison, Rob J.; Lee, Minju; Makiya, Ryu; Matsuda, Yuichi; Motohara, Kentaro; Nakanish, Kouichiro; Ohta, Kouji; Tadaki, Ken-ichi; Tamura, Yoichi; Kodama, Tadayuki; Rujopakarn, Wiphu; Wilson, Grant W.; Yamaguchi, Yuki; Yun, Min S.; Coupon, Jean; Hsieh, Bau-Ching; Foucaud, Sébastien

    2016-12-01

    We present stacking analyses on our ALMA deep 1.1 mm imaging in the Subaru/XMM-Newton Deep Survey Field using 1.6 and 3.6 μm selected galaxies in the CANDELS WFC3 catalog. We detect a stacked flux of ˜0.03-0.05 mJy, corresponding to {L}{IR}\\lt {10}11 {L}⊙ and a star formation rate (SFR) of ˜ 15 {M}⊙ yr-1 at z = 2. We find that galaxies that are brighter in the rest-frame near-infrared tend to also be brighter at 1.1 mm, and galaxies fainter than {m}3.6μ {{m}}=23 do not produce detectable 1.1 mm emission. This suggests a correlation between stellar mass and SFR, but outliers to this correlation are also observed, suggesting strongly boosted star formation or extremely large extinction. We also find tendencies that redder galaxies and galaxies at higher redshifts are brighter at 1.1 mm. Our field contains z˜ 2.5 Hα emitters and a bright single-dish source. However, we do not find evidence of bias in our results caused by the bright source. By combining the fluxes of sources detected by ALMA and fluxes of faint sources detected with stacking, we recover a 1.1 mm surface brightness of up to 20.3 ± 1.2 Jy deg-2, comparable to the extragalactic background light measured by COBE. Based on the fractions of optically faint sources in our and previous ALMA studies and the COBE measurements, we find that approximately half of the cosmic star formation may be obscured by dust and missed by deep optical surveys. Much deeper and wider ALMA imaging is therefore needed to better constrain the obscured cosmic star formation history.

  5. Constraints on the Space Density of Methane Dwarfs and the Substellar Mass Function from a Deep Near-Infrared Survey.

    PubMed

    Herbst; Thompson; Fockenbrock; Rix; Beckwith

    1999-11-20

    We report preliminary results of a deep near-infrared search for methane-absorbing brown dwarfs; almost 5 yr after the discovery of Gl 229b, there are only a few confirmed examples of this type of object. New J-band, wide-field images, combined with preexisting R-band observations, allow efficient identification of candidates by their extreme (R-J) colors. Follow-up measurements with custom filters can then confirm objects with methane absorption. To date, we have surveyed a total of 11.4 deg2 to J approximately 20.5 and R approximately 25. Follow-up CH4 filter observations of promising candidates in one-fourth of these fields have turned up no methane-absorbing brown dwarfs. With 90% confidence, this implies that the space density of objects similar to Gl 229b is less than 0.012 pc-3. These calculations account for the vertical structure of the Galaxy, which can be important for sensitive measurements. Combining published theoretical atmospheric models with our observations sets an upper limit of alpha

  6. Photostimulable near-infrared persistent luminescent nanoprobes for ultrasensitive and longitudinal deep-tissue bio-imaging.

    PubMed

    Chuang, Yen-Jun; Zhen, Zipeng; Zhang, Fan; Liu, Feng; Mishra, Jyoti P; Tang, Wei; Chen, Hongmin; Huang, Xinglu; Wang, Lianchun; Chen, Xiaoyuan; Xie, Jin; Pan, Zhengwei

    2014-01-01

    In vivo fluorescence imaging suffers from suboptimal signal-to-noise ratio and shallow detection depth, which is caused by the strong tissue autofluorescence under constant external excitation and the scattering and absorption of short-wavelength light in tissues. Here we address these limitations by using a novel type of optical nanoprobes, photostimulable LiGa5O8:Cr(3+) near-infrared (NIR) persistent luminescence nanoparticles, which, with very-long-lasting NIR persistent luminescence and unique photo-stimulated persistent luminescence (PSPL) capability, allow optical imaging to be performed in an excitation-free and hence, autofluorescence-free manner. LiGa5O8:Cr(3+) nanoparticles pre-charged by ultraviolet light can be repeatedly (>20 times) stimulated in vivo, even in deep tissues, by short-illumination (~15 seconds) with a white light-emitting-diode flashlight, giving rise to multiple NIR PSPL that expands the tracking window from several hours to more than 10 days. Our studies reveal promising potential of these nanoprobes in cell tracking and tumor targeting, exhibiting exceptional sensitivity and penetration that far exceed those afforded by conventional fluorescence imaging.

  7. Noninvasive diagnosis and therapeutic effect evaluation of deep vein thrombosis in clinics by near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Li, Ting; Sun, Yunlong; Chen, Xiao; Zhao, Yue; Ren, Rongrong

    2015-01-01

    Deep vein thrombosis (DVT) has become a severe disease with a rising incidence rate. The conventional diagnosis relies on complicated imaging modalities that may also involve invasive contrast agent injection and ionizing procedures (e.g., venography). Noninvasive near-infrared spectroscopy (NIRS) methods have been explored which required the DVT patients to follow some exercise protocols. Here, we attempt to use portable NIRS under patients' natural state for DVT diagnosis. Nine DVT patients and seven healthy subjects participated in NIRS measurements of concentration of oxy- and deoxy-hemoglobins (Δ[HbO2] and Δ[Hb]) relative to data on a tissue mimicking phantom at six particular sites of calves. It was found that Δ[HbO2] is significantly lower in DVT patients than healthy ones, whereas Δ[Hb] is distinctly higher. Moreover, after thrombolytic therapy, both Δ[HbO2] and Δ[Hb] in DVT calves assume a gradual convergence to the curves of healthy ones. This reveals the potential of NIRS for the noninvasive, continuous, and straightforward monitoring/therapeutic effect evaluation of DVT in clinics with appropriate bedside monitoring capability.

  8. Photostimulable Near-Infrared Persistent Luminescent Nanoprobes for Ultrasensitive and Longitudinal Deep-Tissue Bio-Imaging

    PubMed Central

    Chuang, Yen-Jun; Zhen, Zipeng; Zhang, Fan; Liu, Feng; Mishra, Jyoti P.; Tang, Wei; Chen, Hongmin; Huang, Xinglu; Wang, Lianchun; Chen, Xiaoyuan; Xie, Jin; Pan, Zhengwei

    2014-01-01

    In vivo fluorescence imaging suffers from suboptimal signal-to-noise ratio and shallow detection depth, which is caused by the strong tissue autofluorescence under constant external excitation and the scattering and absorption of short-wavelength light in tissues. Here we address these limitations by using a novel type of optical nanoprobes, photostimulable LiGa5O8:Cr3+ near-infrared (NIR) persistent luminescence nanoparticles, which, with very-long-lasting NIR persistent luminescence and unique photo-stimulated persistent luminescence (PSPL) capability, allow optical imaging to be performed in an excitation-free and hence, autofluorescence-free manner. LiGa5O8:Cr3+ nanoparticles pre-charged by ultraviolet light can be repeatedly (>20 times) stimulated in vivo, even in deep tissues, by short-illumination (~15 seconds) with a white light-emitting-diode flashlight, giving rise to multiple NIR PSPL that expands the tracking window from several hours to more than 10 days. Our studies reveal promising potential of these nanoprobes in cell tracking and tumor targeting, exhibiting exceptional sensitivity and penetration that far exceed those afforded by conventional fluorescence imaging. PMID:25285164

  9. Noninvasive near-infrared fluorescent protein-based imaging of tumor progression and metastases in deep organs and intraosseous tissues

    NASA Astrophysics Data System (ADS)

    Jiguet-Jiglaire, Carine; Cayol, Mylène; Mathieu, Sylvie; Jeanneau, Charlotte; Bouvier-Labit, Corinne; Ouafik, L.'houcine; El-Battari, Assou

    2014-01-01

    Whole-body imaging of experimental tumor growth is more feasible within the near-infrared (NIR) optical window because of the highest transparency of mammalian tissues within this wavelength spectrum, mainly due to improved tissue penetration and lower autofluorescence. We took advantage from the recently cloned infrared fluorescent protein (iRFP) together with a human immunodeficiency virus (HIV)-based lentiviral vector to produce virally transduced tumor cells that permanently express this protein. We then noninvasively explored metastatic spread as well as primary tumor growth in deep organs and behind bone barriers. Intrabone tumor growth was investigated through intracranial and intratibial injections of glioblastoma and osteosarcoma cells, respectively, and metastasis was assessed by tail vein injection of melanoma cells. We found that the emitted fluorescence is captured as sharp images regardless of the organ or tissue considered. Furthermore, by overlaying fluorescence spots with the white light, it was possible to afford whole-body images yet never observed before. This approach allowed us to continuously monitor the growth and dissemination of tumor cells with a small number of animals, minimal animal handling, and without the need for any additive. This iRFP-based system provides high-resolution readouts of tumorigenesis that should greatly facilitate preclinical trials with anticancer therapeutic molecules.

  10. Visible and near-infrared spectrophotometry of the Deep Impact ejecta of Comet 9P/Tempel 1

    NASA Astrophysics Data System (ADS)

    Hodapp, Klaus W.; Aldering, Greg; Meech, Karen J.; Cochran, Anita L.; Antilogus, Pierre; Pécontal, Emmanuel; Chickering, William; Blanc, Nathalie; Copin, Yannick; Lynch, David K.; Rudy, Richard J.; Mazuk, S.; Venturini, Catherine C.; Puetter, Richard C.; Perry, Raleigh B.

    2007-03-01

    We have obtained optical spectrophotometry of the evolution of Comet 9P/Tempel 1 after the impact of the Deep Impact probe, using the Supernova Integral Field Spectrograph (SNIFS) at the UH 2.2-m telescope, as well as simultaneous optical and infrared spectra using the Lick Visible-to-Near-Infrared Imaging Spectrograph (VNIRIS). The spatial distribution and temporal evolution of the "violet band" CN (0-0) emission and of the 630 nm [OI] emission was studied. We found that CN emission centered on the nucleus increased in the 2 h after impact, but that this CN emission was delayed compared to the light curve of dust-scattered sunlight. The CN emission also expanded faster than the cloud of scattering dust. The emission of [OI] at 630 nm rose similarly to the scattered light, but then remained nearly constant for several hours after impact. On the day following the impact, both CN and [OI] emission concentrated on the comet nucleus had returned nearly to pre-impact levels. We have also searched for differences in the scattering properties of the dust ejected by the impact compared to the dust released under normal conditions. Compared to the pre-impact state of the comet, we find evidence that the color of the comet was slightly bluer during the post-impact rise in brightness. Long after the impact, in the following nights, the comet colors returned to their pre-impact values. This can be explained by postulating a change to a smaller particle size distribution in the ejecta cloud, in agreement with the findings from mid-infrared observations, or by postulating a large fraction of clean ice particles, or by a combination of these two.

  11. Visible and near-infrared spectrophotometry of the Deep Impact ejecta of Comet 9P/Tempel 1

    NASA Astrophysics Data System (ADS)

    Hodapp, Klaus W.; Aldering, Greg; Meech, Karen J.; Cochran, Anita L.; Antilogus, Pierre; Pécontal, Emmanuel; Chickering, William; Blanc, Nathalie; Copin, Yannick; Lynch, David K.; Rudy, Richard J.; Mazuk, S.; Venturini, Catherine C.; Puetter, Richard C.; Perry, Raleigh B.

    We have obtained optical spectrophotometry of the evolution of Comet 9P/Tempel 1 after the impact of the Deep Impact probe, using the Supernova Integral Field Spectrograph (SNIFS) at the UH 2.2-m telescope, as well as simultaneous optical and infrared spectra using the Lick Visible-to-Near-Infrared Imaging Spectrograph (VNIRIS). The spatial distribution and temporal evolution of the “violet band” CN (0 0) emission and of the 630 nm [OI] emission was studied. We found that CN emission centered on the nucleus increased in the 2 h after impact, but that this CN emission was delayed compared to the light curve of dust-scattered sunlight. The CN emission also expanded faster than the cloud of scattering dust. The emission of [OI] at 630 nm rose similarly to the scattered light, but then remained nearly constant for several hours after impact. On the day following the impact, both CN and [OI] emission concentrated on the comet nucleus had returned nearly to pre-impact levels. We have also searched for differences in the scattering properties of the dust ejected by the impact compared to the dust released under normal conditions. Compared to the pre-impact state of the comet, we find evidence that the color of the comet was slightly bluer during the post-impact rise in brightness. Long after the impact, in the following nights, the comet colors returned to their pre-impact values. This can be explained by postulating a change to a smaller particle size distribution in the ejecta cloud, in agreement with the findings from mid-infrared observations, or by postulating a large fraction of clean ice particles, or by a combination of these two.

  12. Excitation of Molecular Hydrogen in the Orion Bar Photodissociation Region from a Deep Near-infrared IGRINS Spectrum

    NASA Astrophysics Data System (ADS)

    Kaplan, Kyle F.; Dinerstein, Harriet L.; Oh, Heeyoung; Mace, Gregory N.; Kim, Hwihyun; Sokal, Kimberly R.; Pavel, Michael D.; Lee, Sungho; Pak, Soojong; Park, Chan; Sok Oh, Jae; Jaffe, Daniel T.

    2017-04-01

    We present a deep near-infrared spectrum of the Orion Bar Photodissociation Region (PDR) taken with the Immersion Grating INfrared Spectrometer (IGRINS) on the 2.7 m telescope at the McDonald Observatory. IGRINS has high spectral resolution (R∼ {{45,000}}) and instantaneous broad wavelength coverage (1.45–2.45 μm), enabling us to detect 87 emission lines from rovibrationally excited molecular hydrogen (H2) that arise from transitions out of 69 upper rovibration levels of the electronic ground state. These levels cover a large range of rotational and vibrational quantum numbers and excitation energies, making them excellent probes of the excitation mechanisms of H2 and physical conditions within the PDR. The Orion Bar PDR is thought to consist of cooler high density clumps or filaments (T=50{--}250 K, {n}H={10}5{--}{10}7 cm‑3) embedded in a warmer lower density medium (T=250{--}1000 K, {n}H={10}4{--}{10}5 cm‑3). We fit a grid of constant temperature and density Cloudy models, which recreate the observed H2 level populations well, to constrain the temperature to a range of 600–650 K and the density to {n}H=2.5× {10}3{--}{10}4 cm‑3. The best-fit model gives T = 625 K and {n}H=5× {10}3 cm‑3. This well-constrained warm temperature is consistent with kinetic temperatures found by other studies for the Orion Bar’s lower density medium. However, the range of densities well fit by the model grid is marginally lower than those reported by other studies. We could be observing lower density gas than the surrounding medium, or perhaps a density-sensitive parameter in our models is not properly estimated.

  13. MOIRCS DEEP SURVEY. VI. NEAR-INFRARED SPECTROSCOPY OF K-SELECTED STAR-FORMING GALAXIES AT z {approx} 2

    SciTech Connect

    Yoshikawa, Tomohiro; Akiyama, Masayuki; Kajisawa, Masaru; Tokoku, Chihiro; Yamada, Toru; Ichikawa, Takashi; Alexander, David M.; Ohta, Kouji; Suzuki, Ryuji; Tanaka, Ichi; Omata, Koji; Nishimura, Tetsuo; Uchimoto, Yuka K.; Konishi, Masahiro; Koekemoer, Anton M.; Brandt, Niel

    2010-07-20

    We present the results of near-infrared multi-object spectroscopic observations for 37 BzK-color-selected star-forming galaxies conducted with MOIRCS on the Subaru Telescope. The sample is drawn from the K{sub s} -band-selected catalog of the MOIRCS Deep Survey in the GOODS-N region. About half of our samples are selected from the publicly available 24 {mu}m-source catalog of the Multiband Imaging Photometer for Spitzer on board the Spitzer Space Telescope. H{alpha} emission lines are detected from 23 galaxies, of which the median redshift is 2.12. We derived the star formation rates (SFRs) from extinction-corrected H{alpha} luminosities. The extinction correction is estimated from the spectral energy distribution (SED) fitting of multiband photometric data covering UV to near-infrared wavelengths. The Balmer decrement of the stacked emission lines shows that the amount of extinction for the ionized gas is larger than that for the stellar continuum. From a comparison of the extinction-corrected H{alpha} luminosity and other SFR indicators, we found that the relation between the dust properties of stellar continuum and ionized gas is different depending on the intrinsic SFR (differential extinction). We compared SFRs estimated from extinction-corrected H{alpha} luminosities with stellar masses estimated from SED fitting. The comparison shows no correlation between SFR and stellar mass. Some galaxies with stellar mass smaller than {approx}10{sup 10} M{sub sun} show SFRs higher than {approx}100 M{sub sun} yr{sup -1}. The specific SFRs (SSFRs) of these galaxies are remarkably high; galaxies which have SSFR higher than {approx}10{sup -8} yr{sup -1} are found in eight of the present sample. From the best-fit parameters of SED fitting for these high-SSFR galaxies, we find that the average age of the stellar population is younger than 100 Myr, which is consistent with the implied high SSFR. The large SFR implies the possibility that the high-SSFR galaxies significantly

  14. Chandra Deep X-ray Observation of a Typical Galactic Plane Region and Near-Infrared Identification

    NASA Technical Reports Server (NTRS)

    Ebisawa, K.; Tsujimoto, M.; Paizis, A.; Hamaguichi, K.; Bamba, A.; Cutri, R.; Kaneda, H.; Maeda, Y.; Sato, G.; Senda, A.

    2004-01-01

    Using the Chandra Advanced CCD Imaging Spectrometer Imaging array (ACIS-I), we have carried out a deep hard X-ray observation of the Galactic plane region at (l,b) approx. (28.5 deg,0.0 deg), where no discrete X-ray source has been reported previously. We have detected 274 new point X-ray sources (4 sigma confidence) as well as strong Galactic diffuse emission within two partidly overlapping ACIS-I fields (approx. 250 sq arcmin in total). The point source sensitivity was approx. 3 x 10(exp -15)ergs/s/sq cm in the hard X-ray band (2-10 keV and approx. 2 x 10(exp -16) ergs/s/sq cm in the soft band (0.5-2 keV). Sum of all the detected point source fluxes account for only approx. 10 % of the total X-ray fluxes in the field of view. In order to explain the total X-ray fluxes by a superposition of fainter point sources, an extremely rapid increase of the source population is required below our sensitivity limit, which is hardly reconciled with any source distribution in the Galactic plane. Therefore, we conclude that X-ray emission from the Galactic plane has truly diffuse origin. Only 26 point sources were detected both in the soft and hard bands, indicating that there are two distinct classes of the X-ray sources distinguished by the spectral hardness ratio. Surface number density of the hard sources is only slightly higher than observed at the high Galactic latitude regions, strongly suggesting that majority of the hard X-ray sources are active galaxies seen through the Galactic plane. Following the Chandra observation, we have performed a near-infrared (NIR) survey with SOFI at ESO/NTT to identify these new X-ray sources. Since the Galactic plane is opaque in NIR, we did not see the background extragalactic sources in NIR. In fact, only 22 % of the hard sources had NIR counterparts which are most likely to be Galactic origin. Composite X-ray energy spectrum of those hard X-ray sources having NIR counterparts exhibits a narrow approx. 6.7 keV iron emission line, which

  15. New insights to the photometric structure of Blue Compact Dwarf Galaxies from deep near-infrared studies. II. The sample of northern BCDs

    NASA Astrophysics Data System (ADS)

    Noeske, K. G.; Papaderos, P.; Cairós, L. M.; Fricke, K. J.

    2005-01-01

    This paper is part of a series of publications which present a systematic study of Blue Compact Dwarf (BCD) Galaxies in the near infrared (NIR). Compared to the visible light, NIR data allow a better separation of the starburst emission from the light distribution of the old stellar low-surface brightness (LSB) host galaxy. We analyze deep NIR broad band images of a sample of 11 BCDs, observed with the Calar Alto 3.6 m telescope. This work enlarges the samples presented in preceding papers of this study (Noeske et al. \\cite{Noeske2003}, A&A, 410, 481; Cairós et al. \\cite{c03a}, ApJ, 593, 312) by BCDs of the most common morphological type, displaying a regular elliptical LSB host galaxy. The data presented here allow the detection and quantitative study of the extended stellar LSB host galaxy in all sample BCDs. The NIR surface brightness profiles (SBPs) of the LSB host galaxies agree at large galactocentric radii with those from optical studies, showing also an exponential intensity decrease and compatible scale lengths. Similar to Noeske et al. (\\cite{Noeske2003}), we find centrally flattening exponential (type V) SBPs of the host galaxy for several BCDs. Such SBPs remain mostly undetected in optical bands, due to the comparatively stronger starburst emission at these wavelengths. We apply a modified exponential distribution to decompose and quantitatively analyze SBPs of LSB hosts with a type V intensity distribution. We present the results of the surface photometry and the decomposition of SBPs, and discuss individual objects with respect to morphological details of their star-forming regions. Table 2 is also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http:/ /cdsweb.u-strasbg.fr/ cgi-bin/ qcat?J/A+A/429/115 Figures 2 to 11 are only available in electronic form at http://www.edpsciences.org German-Spanish Astronomical Center, Calar Alto, operated by the Max-Planck-Institute for Astronomy, Heidelberg

  16. LUMINOUS AND HIGH STELLAR MASS CANDIDATE GALAXIES AT z Almost-Equal-To 8 DISCOVERED IN THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY

    SciTech Connect

    Yan Haojing; Finkelstein, Steven L.; Huang, Kuang-Han; Ryan, Russell E.; Ferguson, Henry C.; Koekemoer, Anton M.; Grogin, Norman A.; Dickinson, Mark; Newman, Jeffrey A.; Somerville, Rachel S.; Dave, Romeel; Faber, S. M.; Guo Yicheng; Giavalisco, Mauro; Lee, Kyoung-soo; Reddy, Naveen; Siana, Brian D.; Cooray, Asantha R.; Hathi, Nimish P.; and others

    2012-12-20

    One key goal of the Hubble Space Telescope Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey is to track galaxy evolution back to z Almost-Equal-To 8. Its two-tiered ''wide and deep'' strategy bridges significant gaps in existing near-infrared surveys. Here we report on z Almost-Equal-To 8 galaxy candidates selected as F105W-band dropouts in one of its deep fields, which covers 50.1 arcmin{sup 2} to 4 ks depth in each of three near-infrared bands in the Great Observatories Origins Deep Survey southern field. Two of our candidates have J < 26.2 mag, and are >1 mag brighter than any previously known F105W-dropouts. We derive constraints on the bright end of the rest-frame ultraviolet luminosity function of galaxies at z Almost-Equal-To 8, and show that the number density of such very bright objects is higher than expected from the previous Schechter luminosity function estimates at this redshift. Another two candidates are securely detected in Spitzer Infrared Array Camera images, which are the first such individual detections at z Almost-Equal-To 8. Their derived stellar masses are on the order of a few Multiplication-Sign 10{sup 9} M{sub Sun }, from which we obtain the first measurement of the high-mass end of the galaxy stellar mass function at z Almost-Equal-To 8. The high number density of very luminous and very massive galaxies at z Almost-Equal-To 8, if real, could imply a large stellar-to-halo mass ratio and an efficient conversion of baryons to stars at such an early time.

  17. Airborne hyperspectral sensor radiometric self-calibration using near-infrared properties of deep water and vegetation

    NASA Astrophysics Data System (ADS)

    Barbieux, Kévin; Nouchi, Vincent; Merminod, Bertrand

    2016-10-01

    Retrieving the water-leaving reflectance from airborne hyperspectral data implies to deal with three steps. Firstly, the radiance recorded by an airborne sensor comes from several sources: the real radiance of the object, the atmospheric scattering, sky and sun glint and the dark current of the sensor. Secondly, the dispersive element inside the sensor (usually a diffraction grating or a prism) could move during the flight, thus shifting the observed spectra on the wavelengths axis. Thirdly, to compute the reflectance, it is necessary to estimate, for each band, what value of irradiance corresponds to a 100% reflectance. We present here our calibration method, relying on the absorption features of the atmosphere and the near-infrared properties of common materials. By choosing proper flight height and flight lines angle, we can ignore atmospheric and sun glint contributions. Autocorrelation plots allow to identify and reduce the noise in our signals. Then, we compute a signal that represents the high frequencies of the spectrum, to localize the atmospheric absorption peaks (mainly the dioxygen peak around 760 nm). Matching these peaks removes the shift induced by the moving dispersive element. Finally, we use the signal collected over a Lambertian, unit-reflectance surface to estimate the ratio of the system's transmittances to its near-infrared transmittance. This transmittance is computed assuming an average 50% reflectance of the vegetation and nearly 0% for water in the near-infrared. Results show great correlation between the output spectra and ground measurements from a TriOS Ramses and the water-insight WISP-3.

  18. Near infrared detectors for SNAP

    SciTech Connect

    Schubnell, M.; Barron, N.; Bebek, C.; Brown, M.G.; Borysow, M.; Cole, D.; Figer, D.; Lorenzon, W.; Mostek, N.; Mufson, S.; Seshadri, S.; Smith, R.; Tarle, G.

    2006-05-23

    Large format (1k x 1k and 2k x 2k) near infrared detectors manufactured by Rockwell Scientific Center and Raytheon Vision Systems are characterized as part of the near infrared R&D effort for SNAP (the Super-Nova/Acceleration Probe). These are hybridized HgCdTe focal plane arrays with a sharp high wavelength cut-off at 1.7 um. This cut-off provides a sufficiently deep reach in redshift while it allows at the same time low dark current operation of the passively cooled detectors at 140 K. Here the baseline SNAP near infrared system is briefly described and the science driven requirements for the near infrared detectors are summarized. A few results obtained during the testing of engineering grade near infrared devices procured for the SNAP project are highlighted. In particular some recent measurements that target correlated noise between adjacent detector pixels due to capacitive coupling and the response uniformity within individual detector pixels are discussed.

  19. Probability of the Physical Association of 104 Blended Companions to Kepler Objects of Interest Using Visible and Near-infrared Adaptive Optics Photometry

    NASA Astrophysics Data System (ADS)

    Atkinson, Dani; Baranec, Christoph; Ziegler, Carl; Law, Nicholas; Riddle, Reed; Morton, Tim

    2017-01-01

    We determine probabilities of physical association for stars in blended Kepler Objects of Interest (KOIs), and find that 14.5{ % }-3.4 % +3.8 % of companions within ∼4″ are consistent with being physically unassociated with their primary. This produces a better understanding of potential false positives in the Kepler catalog and will guide models of planet formation in binary systems. Physical association is determined through two methods of calculating multi-band photometric parallax using visible and near-infrared adaptive optics observations of 84 KOI systems with 104 contaminating companions within ∼4″. We find no evidence that KOI companions with separations of less than 1″ are more likely to be physically associated than KOI companions generally. We also reinterpret transit depths for 94 planet candidates, and calculate that 2.6% ± 0.4% of transits have R> 15{R}\\oplus , which is consistent with prior modeling work.

  20. STAR-FORMING REGION Sh 2-233IR. I. DEEP NEAR-INFRARED OBSERVATIONS TOWARD THE EMBEDDED STELLAR CLUSTERS

    SciTech Connect

    Yan, Chi-Hung; Wang, Shiang-Yu; Su, Yu-Nang; Minh, Y. C.; Ginsburg, Adam

    2010-09-01

    We observed the Sh 2-233IR (S233IR) region with better sensitivity in the near-infrared than in previous studies of this region. By applying statistical subtraction of the background stars, we identified member sources and derived the age and mass of three distinguishable sub-groups in this region: Sh 2-233IR NE, Sh 2-233IR SW, and the 'distributed stars' over the whole cloud. Star formation may occur sequentially with a relatively small age difference ({approx}0.2-0.3 Myr) between subclusters. We found that the slopes for the initial mass function ({Gamma} {approx} -0.5) of two subclusters are flatter than those of Salpeter, which suggests that more massive stars were preferentially formed in those clusters compared to other Galactic star-forming regions. These subclusters may not result from the overall collapse of the whole cloud, but have formed by triggering before the previous star formation activities disturbed the natal molecular cloud. Additionally, high star formation efficiency ({approx}>40%) of the subclusters may also suggest that stars form very efficiently in the center of the northeast.

  1. The Lower Main Sequence of ω Centauri from Deep Hubble Space Telescope NICMOS Near-Infrared Observations

    NASA Astrophysics Data System (ADS)

    Pulone, Luigi; De Marchi, Guido; Paresce, Francesco; Allard, France

    1998-01-01

    A 20" × 20" field located ~7' from the center of the massive galactic globular cluster ω Centauri (NGC 5139) was observed by the NIC2 camera of the Near-Infrared Camera and Multiobject Spectrometer on board the Hubble Space Telescope (HST) through the F110W and F160W broadband filters centered at 1.1 and 1.6 μm for a total of 3000 and 4000 s for the two filters, respectively. Standard photometric analysis of the resulting images yields 340 stars with a signal above a 10 σ threshold in both filters, covering the range of HST m160 magnitudes between 20 and 26, the deepest probe yet of a globular cluster in this wavelength region. These objects form a well-defined sequence in the m160 versus m110-m160 plane that is consistent with the theoretical near-IR color-magnitude diagram expected from recent low-mass stellar model calculations. The resulting stellar luminosity function increases steadily with increasing magnitude up to a peak at m160~=25, where it turns over and drops slowly down to the detection limit set by the incompleteness limit of 60% at m160~=26. With the theoretical mass-luminosity relationship that provides the best fit to the IR color-magnitude diagram, we obtain an excellent fit to the observed luminosity function down to a mass of ~0.2 Msolar with a power-law mass function having a slope of α=-1. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA under contract NAS5-26555.

  2. Optical focusing deep inside dynamic scattering media with near-infrared time-reversed ultrasonically encoded (TRUE) light

    PubMed Central

    Liu, Yan; Lai, Puxiang; Ma, Cheng; Xu, Xiao; Grabar, Alexander A.; Wang, Lihong V.

    2015-01-01

    Focusing light deep inside living tissue has not been achieved despite its promise to play a central role in biomedical imaging, optical manipulation and therapy. To address this challenge, internal-guide-star-based wavefront engineering techniques—for example, time-reversed ultrasonically encoded (TRUE) optical focusing—were developed. The speeds of these techniques, however, were limited to no greater than 1 Hz, preventing them from in vivo applications. Here we improve the speed of optical focusing deep inside scattering media by two orders of magnitude, and focus diffuse light inside a dynamic scattering medium having a speckle correlation time as short as 5.6 ms, typical of living tissue. By imaging a target, we demonstrate the first focusing of diffuse light inside a dynamic scattering medium containing living tissue. Since the achieved focusing speed approaches the tissue decorrelation rate, this work is an important step towards in vivo deep tissue noninvasive optical imaging, optogenetics and photodynamic therapy. PMID:25556918

  3. ON THE FORMATION TIMESCALE OF MASSIVE CLUSTER ELLIPTICALS BASED ON DEEP NEAR-INFRARED SPECTROSCOPY AT z {approx} 2

    SciTech Connect

    Tanaka, Masayuki; Kodama, Tadayuki; Koyama, Yusei; Toft, Sune; Zirm, Andrew; Marchesini, Danilo; De Breuck, Carlos; Kurk, Jaron; Tanaka, Ichi

    2013-08-01

    We present improved constraints on the formation timescale of massive cluster galaxies based on rest-frame optical spectra of galaxies in a forming cluster located at z = 2.16. The spectra are obtained with MOIRCS on the Subaru Telescope with an integration time of {approx}7 hr. We achieve accurate redshift measurements by fitting spectral energy distributions using the spectra and broadband photometry simultaneously, allowing us to identify probable cluster members. Clusters at low redshifts are dominated by quiescent galaxies, but we find that quiescent galaxies and star-forming galaxies coexist in this z = 2 system. Interestingly, the quiescent galaxies form a weak red sequence in the process of forming. By stacking the spectra of star-forming galaxies, we observe strong emission lines such as [O II] and [O III] and we obtain a tentative hint of active galactic nucleus activities in these galaxies. On the other hand, the stacked spectrum of the quiescent galaxies reveals a clear 4000 A break with a possible Ca II H+K absorption feature and strong emission lines such as [O II] are absent in the spectrum, confirming the quiescent nature of these galaxies. We then perform detailed spectral analyses of the stacked spectrum, which suggest that these massive quiescent galaxies formed at redshifts between 3 and 4 on a timescale of {approx}< 0.5 Gyr. This short formation timescale is not reproduced in recent numerical simulations. We discuss possible mechanisms for how these galaxies form 10{sup 11} M{sub Sun} stellar mass on a short timescale and become red and quiescent by z = 2.

  4. Near-Infrared Photometric Parameters of Bulge Globular Clusters from the VVV Survey

    NASA Astrophysics Data System (ADS)

    Cohen, R. E.

    2015-05-01

    Despite spanning a remarkable variety of properties (e.g., mass, metallicity and horizontal branch morphology), severe and variable extinction has often thwarted detailed analyses of the globular clusters of the Milky Way bulge. We present results from recent and ongoing investigations of these clusters using deep, wide-field near-infrared photometry independently, and also in combination with, the plethora of existing photometry and spectroscopy. The results and their homogeneity facilitate not only the characterization of relations between cluster photometric properties and abundances and comparison to evolutionary models, but can also corroborate and further constrain recent results regarding the extinction law of the inner Milky Way.

  5. VVV SURVEY NEAR-INFRARED PHOTOMETRY OF KNOWN BULGE RR LYRAE STARS: THE DISTANCE TO THE GALACTIC CENTER AND ABSENCE OF A BARRED DISTRIBUTION OF THE METAL-POOR POPULATION

    SciTech Connect

    Dékány, I.; Minniti, D.; Catelan, M.; Zoccali, M.; Hempel, M.; Saito, R. K.

    2013-10-20

    We have combined optical and near-infrared data of known RR Lyrae (RRL) stars in the bulge in order to study the spatial distribution of its metal-poor component by measuring precise reddening values and distances of 7663 fundamental-mode RRL stars with high-quality photometry. We obtain a distance to the Galactic center of R {sub 0} = 8.33 ± 0.05 ± 0.14 kpc. We find that the spatial distribution of the RRL stars differs from the structures traced by the predominantly metal-rich red clump (RC) stars. Unlike the RC stars, the RRL stars do not trace a strong bar, but have a more spheroidal, centrally concentrated distribution, showing only a slight elongation in its very center. We find a hint of bimodality in the density distribution at high southern latitudes (b < –5°), which needs to be confirmed by extending the areal coverage of the current census. The different spatial distributions of the metal-rich and metal-poor stellar populations suggest that the Milky Way has a composite bulge.

  6. Near-infrared spectroscopy system with non-contact source and detector for in vivo multi-distance measurement of deep biological tissue

    NASA Astrophysics Data System (ADS)

    Funane, Tsukasa; Atsumori, Hirokazu; Kiguchi, Masashi; Tanikawa, Yukari; Okada, Eiji

    2013-03-01

    A non-contact near-infrared spectroscopy (NIRS) scanning system with a phosphor cell placed on the skin for in vivo measurement of biological tissue was developed and evaluated. Because the phosphor is excited by the light that propagates in the tissue, and the excitation light is cut by optical filters, the light that propagates in the tissue is selectively detected. The non-contact system was extended to create a scanning system that can flexibly change source positions with a galvano scanner. The optical scanning system was used for non-contact measurement of the human forearm muscle, and the dependence of optical-density change (ΔOD) caused by the upper-arm occlusion and release on source-detector distance was observed. The obtained ΔOD demonstrates the effectiveness of using this system for multi-distance human-forearm measurement. Furthermore, a human forehead was measured with the system. To extract a deep-layer signal, a surface-layer subtraction method with short-distance regression was applied to measured data. On the basis of the correlation with a simultaneously measured laser-Doppler flowmetry signal, it was confirmed that the deep-layer signal was successfully extracted. The extraction result demonstrates that the optical scanning system can be used as a multi-distance NIRS system for measuring the human brain activity at the forehead.

  7. Deep imaging survey of young, nearby austral stars . VLT/NACO near-infrared Lyot-coronographic observations

    NASA Astrophysics Data System (ADS)

    Chauvin, G.; Lagrange, A.-M.; Bonavita, M.; Zuckerman, B.; Dumas, C.; Bessell, M. S.; Beuzit, J.-L.; Bonnefoy, M.; Desidera, S.; Farihi, J.; Lowrance, P.; Mouillet, D.; Song, I.

    2010-01-01

    Context. High contrast and high angular resolution imaging is the optimal search technique for substellar companions to nearby stars at physical separations larger than typically 10 AU. Two distinct populations of substellar companions, brown dwarfs and planets, can be probed and characterized. As a result, fossile traces of processes of formation and evolution can be revealed by physical and orbital properties, both for individual systems and as an ensemble. Aims: Since November 2002, we have conducted a large, deep imaging, survey of young, nearby associations of the southern hemisphere. Our goal is detection and characterization of substellar companions with projected separations in the range 10-500 AU. We have observed a sample of 88 stars, primarily G to M dwarfs, younger than 100 Myr, and within 100 pc of Earth. Methods: The VLT/NACO adaptive optics instrument of the ESO Paranal Observatory was used to explore the faint circumstellar environment between typically 0.1 and 10''. Diffraction-limited observations in H and K_s-band combined with Lyot-coronagraphy enabled us to reach primary star-companion brightness ratios as small as 10-6. The existence of planetary mass companions could therefore be probed. We used a standardized observing sequence to precisely measure the position and flux of all detected sources relative to their visual primary star. Repeated observations at several epochs enabled us to discriminate comoving companions from background objects. Results: We report the discovery of 17 new close (0.1-5.0'') multiple systems. HIP 108195 AB and C (F1 III-M6), HIP 84642 AB (a~14 AU, K0-M5) and TWA22 AB (a~1.8 AU; M6-M6) are confirmed comoving systems. TWA22 AB is likely to be a rare astrometric calibrator that can be used to test evolutionary model predictions. Among our complete sample, a total of 65 targets were observed with deep coronagraphic imaging. About 240 faint companion candidates were detected around 36 stars. Follow-up observations with

  8. AN ALMA SURVEY OF SUBMILLIMETER GALAXIES IN THE EXTENDED CHANDRA DEEP FIELD SOUTH: NEAR-INFRARED MORPHOLOGIES AND STELLAR SIZES

    SciTech Connect

    Chen, Chian-Chou; Smail, Ian; Swinbank, A. M.; Simpson, J. M.; Ma, Cheng-Jiun; Alexander, D. M.; Danielson, A. L. R.; Edge, A. C.; Biggs, A. D.; Ivison, R. J.; Brandt, W. N.; Chapman, S. C.; Coppin, K. E. K.; Dannerbauer, H.; Greve, T. R.; Karim, A.; Menten, Karl M.; Schinnerer, E.; Walter, F.; Wardlow, J. L.; and others

    2015-02-01

    We analyze Hubble Space Telescope WFC3/H {sub 160}-band observations of a sample of 48 Atacama Large Millimeter/submillimeter Array detected submillimeter galaxies (SMGs) in the Extended Chandra Deep Field South field, to study their stellar morphologies and sizes. We detect 79% ± 17% of the SMGs in the H {sub 160}-band imaging with a median sensitivity of 27.8 mag, and most (80%) of the nondetections are SMGs with 870 μm fluxes of S {sub 870} < 3 mJy. With a surface brightness limit of μ {sub H} ∼ 26 mag arcsec{sup –2}, we find that 82% ± 9% of the H {sub 160}-band-detected SMGs at z = 1-3 appear to have disturbed morphologies, meaning they are visually classified as either irregulars or interacting systems, or both. By determining a Sérsic fit to the H {sub 160} surface brightness profiles, we derive a median Sérsic index of n = 1.2 ± 0.3 and a median half-light radius of r{sub e} = 4.4{sub −0.5}{sup +1.1} kpc for our SMGs at z = 1-3. We also find significant displacements between the positions of the H {sub 160} component and 870 μm emission in these systems, suggesting that the dusty starburst regions and less-obscured stellar distribution are not colocated. We find significant differences in the sizes and the Sérsic index between our z = 2-3 SMGs and z ∼ 2 quiescent galaxies, suggesting that a major transformation of the stellar light profile is needed in the quenching processes if SMGs are progenitors of the red-and-dead z ∼ 2 galaxies. Given the short-lived nature of SMGs, we postulate that the majority of the z = 2-3 SMGs with S {sub 870} ≳ 2 mJy are early/mid-stage major mergers.

  9. Deep NIR photometry of H I galaxies in the Zone of Avoidance

    NASA Astrophysics Data System (ADS)

    Williams, W. L.; Kraan-Korteweg, R. C.; Woudt, P. A.

    2014-09-01

    Current studies of the peculiar velocity flow field in the local Universe are limited by either the lack of detection or accurate photometry for galaxies at low Galactic latitudes. The contribution to the dynamics of the Local Group of the largely unknown mass distribution in this `Zone of Avoidance' (ZoA) remains controversial. We present here the results of a pilot project to obtain deep near-infrared (NIR) observations of galaxies detected in the systematic Parkes deep H I survey of the ZoA(HIZOA) - 578 galaxies with recession velocities out to 6000 km s-1 were observed with the 1.4 m InfraRed Survey Facility SIRIUS (Simultaneous InfraRed Imager for Unbiased Surveys) camera providing J, H and Ks imaging 2 mag deeper than 2MASS. After star subtraction, the resulting isophotal magnitudes and inclinations of ZoA galaxies are of sufficient accuracy (magnitude errors under 0.1 mag even at high extinction) to ultimately be used to determine cosmic flow fields `in' the ZoA via the NIR Tully-Fisher relation. We further used the observed NIR colours to assess the ratio of the true extinction to the Diffuse Infrared Background Experiment/IRAS extinction deep into the dust layers of the Milky Way. The derived ratio was found to be 0.87 across the HIZOA survey region with no significant variation with Galactic latitude or longitude. This value is in excellent agreement with the completely independently derived factor of 0.86 by Schlafly & Finkbeiner based on Sloan data far away from the Milky Way.

  10. WIYN open cluster study. LXII. Comparison of isochrone systems using deep multi-band photometry of M35

    SciTech Connect

    Thompson, B.; Frinchaboy, P.; Kinemuchi, K.; Sarajedini, A.; Cohen, R.

    2014-11-01

    The current generation of stellar isochrone models exhibits non-negligible discrepancies due to variations in the input physics. The success of each model is determined by how well it fits the observations, and this paper aims to disentangle contributions from the various physical inputs. New deep, wide-field optical and near-infrared photometry (UBVRIJHK{sub S} ) of the cluster M35 is presented, against which several isochrone systems are compared: Padova, PARSEC, Dartmouth, and Y {sup 2}. Two different atmosphere models are applied to each isochrone: ATLAS9 and BT-Settl. For any isochrone set and atmosphere model, observed data are accurately reproduced for all stars more massive than 0.7 M {sub ☉}. For stars less massive than 0.7 M {sub ☉}, Padova and PARSEC isochrones consistently produce higher temperatures than observed. Dartmouth and Y{sup 2} isochrones with BT-Settl atmospheres reproduce optical data accurately; however, they appear too blue in IR colors. It is speculated that molecular contributions to stellar spectra in the near-infrared may not be fully explored, and that future study may reconcile these differences.

  11. Near-infrared hyperspectral reflective confocal microscopy

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Zhang, Yunhai; Miao, Xin; Xue, Xiaojun; Xiao, Yun

    2016-10-01

    A Near-Infrared HyperSpectral Reflective Confocal Microscopy (NIHS-RCM) is proposed in order to get high resolution images of deep biological tissues such as skin. The microscopy system uses a super-continuum laser for illumination, an acousto-optic tunable filter (AOTF) for rapid selection of near-infrared spectrum, a resonant galvanometer scanner for high speed imaging (15f/s) and near-infrared avalanche diode as detector. Porcine skin and other experiments show that the microscopy system could get deep tissue images (180 μm), and show the different ingredients of tissue with different wavelength of illumination. The system has the ability of selectively imaging of multiple ingredients at deep tissue which can be used in skin diseases diagnosis and other fields.

  12. The Munich Near-Infrared Cluster Survey - IV. Biases in the completeness of near-infrared imaging data

    NASA Astrophysics Data System (ADS)

    Snigula, J.; Drory, N.; Bender, R.; Botzler, C. S.; Feulner, G.; Hopp, U.

    2002-11-01

    We present the results of completeness simulations for the detection of point sources as well as redshifted elliptical and spiral galaxies in the K'-band images of the Munich Near-Infrared Cluster Survey (MUNICS). The main focus of this work is to quantify the selection effects introduced by threshold-based object detection algorithms used in deep imaging surveys. Therefore, we simulate objects obeying the well-known scaling relations between effective radius and central surface brightness, for both de Vaucouleurs and exponential profiles. The results of these simulations, while presented for the MUNICS project, are applicable in a much wider context to deep optical and near-infrared selected samples. We investigate the detection probability as well as the reliability for recovering the true total magnitude with Kron-like (adaptive) aperture photometry. The results are compared with the predictions of the visibility theory of Disney and Phillipps in terms of the detection rate and the lost-light fraction. Additionally, the effects attributable to seeing are explored. The results show a bias against detecting high-redshifted massive elliptical galaxies in comparison to disc galaxies with exponential profiles, and that the measurements of the total magnitudes for intrinsically bright elliptical galaxies are systematically too faint. Disc galaxies, in contrast, show no significant offset in the magnitude measurement of luminous objects. Finally, we present an analytic formula to predict the completeness of point sources using only basic image parameters.

  13. Changes in Motor-Related Cortical Activity Following Deep Brain Stimulation for Parkinson’s Disease Detected by Functional Near Infrared Spectroscopy: A Pilot Study

    PubMed Central

    Morishita, Takashi; Higuchi, Masa-aki; Saita, Kazuya; Tsuboi, Yoshio; Abe, Hiroshi; Inoue, Tooru

    2016-01-01

    It remains unclear how deep brain stimulation (DBS) modulates the global neuronal network involving cortical activity. We aimed to evaluate changes in cortical activity in six (two men; four women) patients with Parkinson’s disease (PD) who underwent unilateral globus pallidus interna (GPI) DBS surgery using a multi-channel near infrared spectroscopy (NIRS) system. As five of the patients were right-handed, DBS was performed on the left in these five cases. The mean age was 66.8 ± 4.0 years. The unified Parkinson’s disease rating scale (UPDRS) motor scores were evaluated at baseline and 1- and 6-month follow-up. Task-related NIRS experiments applying the block design were performed at baseline and 1-month follow-up. The mean of the total UPDRS motor score was 48.5 ± 11.1 in the off-medication state preoperatively. Postoperatively, total UPDRS motor scores improved to 26.8 ± 16.6 (p < 0.05) and 22.2 ± 8.6 (p < 0.05) at 1- and 6-month follow-up, respectively. A task-related NIRS experiment showed a postoperative increase in the cortical activity of the prefrontal cortex comparable to the preoperative state. To our knowledge, this is the first study to use a multi-channel NIRS system for PD patients treated with DBS. In this pilot study, we showed changes in motor-associated cortical activities following DBS surgery. Therapeutic DBS was concluded to have promoted the underlying neuronal network remodeling. PMID:28018196

  14. Near-infrared photometric observations of Nova Ophiuchi 2012

    NASA Astrophysics Data System (ADS)

    Raj, Ashish; Ashok, N. M.; Banerjee, D. P. K.; Raman, V. Venkata

    2012-04-01

    Ashish Raj, N. M. Ashok, D. P. K. Banerjee and V. Venkata Raman, Physical Research Laboratory, report near-infrared J-, H-, and K-band photometry of the Nova Oph 2012 (cf. CBET 3072, 3081) obtained with the Mt. Abu 1.2-m telescope (+PRL Near-Infrared NICMOS3 Imager/Spectrometer). The preliminary reduction of these Mt. Abu observations, of Mar. 29, 31 and Apr. 2, 3 UT shows the brightening of the nova in the JHK bands.

  15. EXTENDED PHOTOMETRY FOR THE DEEP2 GALAXY REDSHIFT SURVEY: A TESTBED FOR PHOTOMETRIC REDSHIFT EXPERIMENTS

    SciTech Connect

    Matthews, Daniel J.; Newman, Jeffrey A.; Coil, Alison L.; Cooper, Michael C.; Gwyn, Stephen D. J. E-mail: janewman@pitt.edu E-mail: m.cooper@uci.edu

    2013-02-15

    This paper describes a new catalog that supplements the existing DEEP2 Galaxy Redshift Survey photometric and spectroscopic catalogs with ugriz photometry from two other surveys: the Canada-France-Hawaii Legacy Survey (CFHTLS) and the Sloan Digital Sky Survey (SDSS). Each catalog is cross-matched by position on the sky in order to assign ugriz photometry to objects in the DEEP2 catalogs. We have recalibrated the CFHTLS photometry where it overlaps DEEP2 in order to provide a more uniform data set. We have also used this improved photometry to predict DEEP2 BRI photometry in regions where only poorer measurements were available previously. In addition, we have included improved astrometry tied to SDSS rather than USNO-A2.0 for all DEEP2 objects. In total this catalog contains {approx}27, 000 objects with full ugriz photometry as well as robust spectroscopic redshift measurements, 64% of which have r > 23. By combining the secure and accurate redshifts of the DEEP2 Galaxy Redshift Survey with ugriz photometry, we have created a catalog that can be used as an excellent testbed for future photo-z studies, including tests of algorithms for surveys such as LSST and DES.

  16. Near infrared imaging with nanoparticles.

    PubMed

    Altinoğlu, Erhan I; Adair, James H

    2010-01-01

    Near infrared imaging has presented itself as a powerful diagnostic technique with potential to serve as a minimally invasive, nonionizing method for sensitive, deep tissue diagnostic imaging. This potential is further realized with the use of nanoparticle (NP)-based near infrared (NIR) contrast agents that are not prone to the rapid photobleaching and instability of their organic counterparts. This review discusses applications that have successfully demonstrated the utility of nanoparticles for NIR imaging, including NIR-emitting semiconductor quantum dots (QDs), resonant gold nanoshells, and dye-encapsulating nanoparticles. NIR QDs demonstrate superior optical performance with exceptional fluorescence brightness stability. However, the heavy metal composition and high propensity for toxicity hinder future application in clinical environments. NIR resonant gold nanoshells also exhibit brilliant signal intensities and likewise have none of the photo- or chemical-instabilities characteristic of organic contrast agents. However, concerns regarding ineffectual clearance and long-term accumulation in nontarget organs are a major issue for this technology. Finally, NIR dye-encapsulating nanoparticles synthesized from calcium phosphate (CP) also demonstrate improved optical performances by shielding the component dye from undesirable environmental influences, thereby enhancing quantum yields, emission brightness, and fluorescent lifetime. Calcium phosphate nanoparticle (CPNP) contrast agents are neither toxic, nor have issues with long-term sequestering, as they are readily dissolved in low pH environments and ultimately absorbed into the system. Though perhaps not as optically superior as QDs or nanoshells, these are a completely nontoxic, bioresorbable option for NP-based NIR imaging that still effectively improves the optical performance of conventional organic agents.

  17. DEEP NEAR-INFRARED IMAGING OF THE {rho} Oph CLOUD CORE: CLUES TO THE ORIGIN OF THE LOWEST-MASS BROWN DWARFS

    SciTech Connect

    Marsh, Kenneth A.; Plavchan, Peter; Kirkpatrick, J. Davy; Lowrance, Patrick J.; Cutri, Roc M.; Velusamy, Thangasamy E-mail: plavchan@ipac.caltech.ed E-mail: lowrance@ipac.caltech.ed E-mail: Thangasamy.Velusamy@jpl.nasa.go

    2010-08-10

    A search for young substellar objects in the {rho} Oph cloud core region has been made with the aid of multiband profile-fitting point-source photometry of the deep-integration Combined Calibration Scan images of the 2MASS extended mission in the J, H, and K{sub s} bands, and Spitzer IRAC images at 3.6, 4.5, 5.8, and 8.0 {mu}m. The field of view of the combined observations was 1{sup 0} x 9.'3, and the 5{sigma} limiting magnitude at J was 20.5. Comparison of the observed spectral energy distributions with the predictions of the COND and DUSTY models, for an assumed age of 1 Myr, supports the identification of many of the sources with brown dwarfs and enables the estimation of effective temperature, T {sub eff}. The cluster members are then readily distinguishable from background stars by their locations on a plot of flux density versus T {sub eff}. The range of estimated T {sub eff} values extends down to {approx}750 K which, based on the COND model, would suggest the presence of objects of sub-Jupiter mass. The results also suggest that the mass function for the {rho} Oph cloud resembles that of the {sigma} Orionis cluster based on a recent study, with both rising steadily toward lower masses. The other main result from our study is the apparent presence of a progressive blueward skew in the distribution of J - H and H - K{sub s} colors, such that the blue end of the range becomes increasingly bluer with increasing magnitude. We suggest that this behavior might be understood in terms of the 'ejected stellar embryo' hypothesis, whereby some of the lowest-mass brown dwarfs could escape to locations close to the front edge of the cloud, and thereby be seen with less extinction.

  18. The VVDS-VLA deep field. II. Optical and near infrared identifications of VLA S1.4 GHz > 80 μ Jy sources in the VIMOS VLT deep survey VVDS-02h field

    NASA Astrophysics Data System (ADS)

    Ciliegi, P.; Zamorani, G.; Bondi, M.; Pozzetti, L.; Bolzonella, M.; Gregorini, L.; Garilli, B.; Iovino, A.; McCracken, H. J.; Mellier, Y.; Radovich, M.; de Ruiter, H. R.; Parma, P.; Bottini, D.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Picat, J. P.; Scaramella, R.; Scodeggio, M.; Tresse, L.; Vettolani, G.; Zanichelli, A.; Adami, C.; Arnaboldi, M.; Arnouts, S.; Bardelli, S.; Cappi, A.; Charlot, S.; Contini, T.; Foucaud, S.; Franzetti, P.; Guzzo, L.; Ilbert, O.; Marano, B.; Marinoni, C.; Mathez, G.; Mazure, A.; Meneux, B.; Merighi, R.; Merluzzi, P.; Paltani, S.; Pollo, A.; Zucca, E.; Bongiorno, A.; Busarello, G.; Gavignaud, I.; Pellò, R.; Ripepi, V.; Rizzo, D.

    2005-10-01

    In this paper we present the optical and near-infrared identifications of the 1054 radio sources detected in the 20 cm deep radio survey down to a 5σ flux limit of ~80 μJy obtained with the VLA in the VIMOS VLT Deep Survey VVDS-02h deep field. Using U,B,V,R,I and K data, with limiting magnitudes of UAB˜25.4, BAB˜26.5, VAB˜26.2, RAB˜25.9 IAB˜25.0, JAB˜24.2, KAB˜23.9 (50% completeness) we identified 718 radio sources (~74% of the whole sample). The photometric redshift analysis shows that, in each magnitude bin, the radio sample has a higher median photometric redshift than the whole optical sample, while the median (V-I)AB color of the radio sources is redder than the median color of the whole optical sample. These results suggest that radio detection is preferentially selecting galaxies with higher intrinsic optical luminosity. From the analysis of the optical properties of the radio sources as function of the radio flux, we found that while about 35% of the radio sources are optically unidentified in the higher radio flux bin (S> 1.0 mJy), the percentage of unidentified sources decreases to about 25% in the faintest bins (S< 0.5 mJy). The median IAB magnitude for the total sample of radio sources, i.e. including also the unidentified ones, is brighter in the faintest radio bins than in the bin with higher radio flux. This suggests that most of the faintest radio sources are likely to be associated to relatively lower radio luminosity objects at relatively modest redshift, rather than radio-powerful, AGN type objects at high redshift. Using a classification in early-type and late-type galaxies based on the (B-I)AB color and the photometric redshift, we found that the majority of the radio sources below ~0.15 mJy are indeed late-type star forming galaxies. Finally, the radio sources without optical counterpart in our deep imaging have a median radio flux of 0.15 mJy, equal to that of identified sources. Given the very faint optical limits, these

  19. Deep tissue imaging of microfracture and non-displaced fracture of bone using the second and third near-infrared therapeutic windows

    NASA Astrophysics Data System (ADS)

    Sordillo, Laura A.; Pu, Yang; Sordillo, P. P.; Budansky, Yury; Alfano, Robert R.

    2014-03-01

    Near-infrared (NIR) light in the wavelengths of 700 nm to 2,000 nm has three NIR optical, or therapeutic, windows, which allow for deeper depth penetration in scattering tissue media. Microfractures secondary to repetitive stress, particularly in the lower extremities, are an important problem for military recruits and athletes. They also frequently occur in the elderly, or in patients taking bisphosphonates or denosumab. Microfractures can be early predictors of a major bone fracture. Using the second and third NIR therapeutic windows, we investigated the results from images of chicken bone and human tibial bone with microfractures and non-displaced fractures with and without overlying tissues of various thicknesses. Images of bone with microfractures and non-displaced fractures with tissue show scattering photons in the third NIR window with wavelengths between 1,650 nm and 1,870 nm are diminished and absorption is increased slightly from and second NIR windows. Results from images of fractured bones show the attenuation length of light through tissue in the third optical window to be larger than in the second therapeutic window. Use of these windows may aid in the detection of bone microfractures, and thus reduce the incidence of major bone fracture in susceptible groups.

  20. Near-infrared observations of IRAS minisurvey galaxies

    NASA Technical Reports Server (NTRS)

    Carico, David P.; Soifer, B. T.; Elias, J. H.; Matthews, K.; Neugebauer, G.; Beichman, C.; Persson, C. J.; Persson, S. E.

    1987-01-01

    Near infrared photometry at J, H, and K was obtained for 82 galaxies from the IRAS minisurvey. The near infrared colors of these galaxies cover a larger range in J-H and H-K than do normal field spiral galaxies, and evidence is presented of a tighter correlation between the near and far infrared emission in far infrared bright galaxies than exists between the far infrared and the visible emission. These results suggest the presence of dust in the far infrared bright galaxies, with hot dust emission contributing to the 2.2 micron emission, and extinction by dust affecting both the near infrared colors and the visible luminosities. In addition, there is some indication that the infrared emission in many of the minisurvey galaxies is coming from a strong nuclear component.

  1. CANDELS Multiwavelength Catalogs: Source Identification and Photometry in the CANDELS UKIDSS Ultra-deep Survey Field

    NASA Astrophysics Data System (ADS)

    Galametz, Audrey; Grazian, Andrea; Fontana, Adriano; Ferguson, Henry C.; Ashby, M. L. N.; Barro, Guillermo; Castellano, Marco; Dahlen, Tomas; Donley, Jennifer L.; Faber, Sandy M.; Grogin, Norman; Guo, Yicheng; Huang, Kuang-Han; Kocevski, Dale D.; Koekemoer, Anton M.; Lee, Kyoung-Soo; McGrath, Elizabeth J.; Peth, Michael; Willner, S. P.; Almaini, Omar; Cooper, Michael; Cooray, Asantha; Conselice, Christopher J.; Dickinson, Mark; Dunlop, James S.; Fazio, G. G.; Foucaud, Sebastien; Gardner, Jonathan P.; Giavalisco, Mauro; Hathi, N. P.; Hartley, Will G.; Koo, David C.; Lai, Kamson; de Mello, Duilia F.; McLure, Ross J.; Lucas, Ray A.; Paris, Diego; Pentericci, Laura; Santini, Paola; Simpson, Chris; Sommariva, Veronica; Targett, Thomas; Weiner, Benjamin J.; Wuyts, Stijn; the CANDELS Team

    2013-06-01

    We present the multiwavelength—ultraviolet to mid-infrared—catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc , i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5 μm from SEDS; 5.8 and 8.0 μm from SpUDS). The present catalog is F160W-selected and contains 35, 932 sources over an area of 201.7 arcmin2 and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.

  2. CANDELS MULTIWAVELENGTH CATALOGS: SOURCE IDENTIFICATION AND PHOTOMETRY IN THE CANDELS UKIDSS ULTRA-DEEP SURVEY FIELD

    SciTech Connect

    Galametz, Audrey; Grazian, Andrea; Fontana, Adriano; Castellano, Marco; Ferguson, Henry C.; Dahlen, Tomas; Grogin, Norman; Huang, Kuang-Han; Koekemoer, Anton M.; Ashby, M. L. N.; Willner, S. P.; Barro, Guillermo; Faber, Sandy M.; Guo, Yicheng; Kocevski, Dale D.; Lee, Kyoung-Soo; McGrath, Elizabeth J.; Peth, Michael; Almaini, Omar; Collaboration: CANDELS team; and others

    2013-06-01

    We present the multiwavelength-ultraviolet to mid-infrared-catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, R{sub c} , i', and z' band data from Subaru/Suprime-Cam; Y and K{sub s} band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5 {mu}m from SEDS; 5.8 and 8.0 {mu}m from SpUDS). The present catalog is F160W-selected and contains 35, 932 sources over an area of 201.7 arcmin{sup 2} and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.

  3. Near infrared leaf reflectance modeling

    NASA Technical Reports Server (NTRS)

    Parrish, J. B.

    1985-01-01

    Near infrared leaf reflectance modeling using Fresnel's equation (Kumar and Silva, 1973) and Snell's Law successfully approximated the spectral curve for a 0.25-mm turgid oak leaf lying on a Halon background. Calculations were made for ten interfaces, air-wax, wax-cellulose, cellulose-water, cellulose-air, air-water, and their inverses. A water path of 0.5 mm yielded acceptable results, and it was found that assignment of more weight to those interfaces involving air versus water or cellulose, and less to those involving wax, decreased the standard deviation of the error for all wavelengths. Data suggest that the air-cell interface is not the only important contributor to the overall reflectance of a leaf. Results also argue against the assertion that the near infrared plateau is a function of cell structure within the leaf.

  4. Near-Infrared Faint Galaxies in the Subaru Deep Field: Comparing the Theory with Observations for Galaxy Counts, Colors, and Size Distributions to K ~ 24.5

    NASA Astrophysics Data System (ADS)

    Totani, Tomonori; Yoshii, Yuzuru; Maihara, Toshinori; Iwamuro, Fumihide; Motohara, Kentaro

    2001-10-01

    Galaxy counts in the K band, (J-K) colors, and apparent size distributions of faint galaxies in the Subaru Deep Field (SDF) down to K~24.5 were studied in detail. Special attention has been paid to take into account various selection effects, including the cosmological dimming of surface brightness, to avoid any systematic bias that may be the origin of controversy in previously published results. We also tried to be very careful about systematic model uncertainties; we present a comprehensive survey of these systematic uncertainties and dependence on various parameters, and we have shown that the dominant factors to determine galaxy counts in this band are cosmology and number evolution. We found that the pure luminosity evolution (PLE) model is very consistent with all the SDF data down to K~22.5, without any evidence for number or size evolution in a low-density, Λ-dominated flat universe, which is now favored by various cosmological observations. On the other hand, a number evolution of galaxies with η~2, when invoked as the luminosity conserving mergers as φ*~(1+z)η and L*~(1+z)-η for all types of galaxies, is necessary to explain the data in the Einstein-de Sitter universe. If the popular Λ-dominated universe is taken for granted, our result then gives a strong constraint on the number evolution of giant elliptical or early-type galaxies to z~1-2 that must be met by any models in the hierarchically clustering universe, since such galaxies are the dominant population in this magnitude range (K<~22.5). A number evolution with η~1 is already difficult to reconcile with the data in this universe. On the other hand, number evolution of late-type galaxies and/or dwarf galaxies, which has been suggested by previous studies of optical galaxies, is allowed from the data. In the fainter magnitude range of K>~22.5, we found a slight excess of observed counts over the prediction of the PLE model when elliptical galaxies are treated as a single population. We

  5. Thermal Emission Photometry of Deep Impact Flyby Target (163249) 2002 GT

    NASA Astrophysics Data System (ADS)

    Lim, Lucy F.; Moskovitz, N. A.; Licandro, J.; Emery, J. P.; Reddy, V.; Vilas, F.; 2002 GT Observing Team

    2013-10-01

    Near-Earth asteroid (163249) 2002 GT is now the target of a Deep Impact spacecraft flyby in Jan. 2020 (see Pittichova et al., this volume, for details of the flyby and observing campaign). Thermal emission photometry of 2002 GT was obtained from NIRI on Gemini-North in the L' and M' filters, which are centered at 3.76 and 4.68 microns respectively. J- and K-band reflectance photometry was also acquired in support of the thermal observations. The full JKL'M' set was acquired on UT 2013-Jun-13 at a solar phase angle of 53 degrees. A further set of photometry in J, K, and L' only was carried out on 2013-Jun-19 at a phase angle of 65 degrees. High water vapor conditions at Mauna Kea during this period unfortunately prevented acquisition of a second set of M' measurements. In addition, N-band photometry of 2002 GT was conducted on 2013-Jun-10 from CanariCam at the 10-meter Gran Telescopio Canarias using a beta version of the moving object guiding system. Data were acquired in three filters between 8.7 and 12.5 microns, although the limitations of the guiding are complicating the analysis. (We note that N-band observing was not offered by either Gemini or IRTF during this apparition.) Data analysis is ongoing and results will be discussed. We appreciate the efforts of the Gemini and GTC staff in support of these observing programs.

  6. Jupiter in blue, ultraviolet and near infrared

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These three images of Jupiter, taken through the narrow angle camera of NASA's Cassini spacecraft from a distance of 77.6 million kilometers (48.2 million miles) on October 8, reveal more than is apparent to the naked eye through a telescope.

    The image on the left was taken through the blue filter. The one in the middle was taken in the ultraviolet. The one on the right was taken in the near infrared.

    The blue-light filter is within the part of the electromagnetic spectrum detectable by the human eye. The appearance of Jupiter in this image is, consequently, very familiar. The Great Red Spot (below and to the right of center) and the planet's well-known banded cloud lanes are obvious. The brighter bands of clouds are called zones and are probably composed of ammonia ice particles. The darker bands are called belts and are made dark by particles of unknown composition intermixed with the ammonia ice.

    Jupiter's appearance changes dramatically in the ultraviolet and near infrared images. These images are near negatives of each other and illustrate the way in which observations in different wavelength regions can reveal different physical regimes on the planet.

    All gases scatter sunlight efficiently at short wavelengths; this is why the sky appears blue on Earth. The effect is even more pronounced in the ultraviolet. The gases in Jupiter's atmosphere, above the clouds, are no different. They scatter strongly in the ultraviolet, making the deep banded cloud layers invisible in the middle image. Only the very high altitude haze appears dark against the bright background. The contrast is reversed in the near infrared, where methane gas, abundant on Jupiter but not on Earth, is strongly absorbing and therefore appears dark. Again the deep clouds are invisible, but now the high altitude haze appears relatively bright against the dark background. High altitude haze is seen over the poles and the equator.

    The Great Red Spot, prominent in all images, is

  7. Flamingos near-infrared study of the Serpens cloud

    NASA Astrophysics Data System (ADS)

    Hasan, Priya

    We present the results of a deep near-infrared imaging survey of the Serpens Cloud made with FLAMINGOS at the 2.1 m telescope at Kitt Peak National Observatory. We study the distribution of young embedded sources using the nearest neighbor method applied to a carefully selected sample of near-infrared excess (NIRX) stars that trace the latest episode of star formation in the complex. Our analysis finds the existence of six clusters, of which three are new in the molecular cloud. We determined a median age for the cluster to be 1-2 Myr at a mean distance of 300 pc.

  8. Near infrared laser ocular bioeffects

    SciTech Connect

    Lund, D.J.; Beatrice, E.S.

    1989-05-01

    Thresholds for laser chorioretinal injury in the red end of the visible spectrum and the near-infrared (IR-A) spectral regions are presented. An unpredicted wavelength dependence of the injury threshold for single Q-switched pulses is demonstrated. Four lasers were used to determine thresholds at 40 wavelengths between 532 nm and 1064 nm: a ruby laser, a neodymium:YAG-pumped dye laser, an erbium:YLF laser and an alexandrite laser. Despite many careful and repeated efforts to determine a cause for the variation due to possible variations in the lasers or other aspects of the experimental technique and due to biological absorption properties of the eye, there is no complete or obvious explanation for the significant variations of threshold with small changes in wavelength. The implications of these findings for laser safety standards are presented.

  9. Functional near-infrared neuroimaging.

    PubMed

    Izzetoglu, Kurtulus; Bunce, Scott; Izzetoglu, Meltem; Onaral, Banu; Pourrezaei, Kambiz

    2004-01-01

    Functional near-infrared (fNIR) spectroscopy is a wearable neuroimaging device that enables the continuous, non-invasive, and portable monitoring of changes in blood oxygen and blood volume related to human brain function. Over the last three years, studies in the laboratory and under field conditions have established the positive correlation between a participant's performance and oxygenation responses as a function of task load. Our findings indicate that fNIR can effectively monitor attention and working memory in real-life situations. These experimental outcomes compare favorably with functional magnetic resonance imaging (fMRI) studies, and in particular, with the blood oxygenation level dependent (BOLD) signal. The capacity to monitor brain hemodynamics with a wearable device holds promise for the use of fNIR in the creation of a symbiotic relationship between the user and his/her everyday environment. Moreover, under operational conditions, the fNIR system is amenable to integration with other established physiological and neurobehavioral measures, including EEG, eye tracking, pupil reflex, heart rate variability, respiration and electrodermal activity.

  10. VizieR Online Data Catalog: Deep VI photometry of Sgr dIrr (Beccari+, 2014)

    NASA Astrophysics Data System (ADS)

    Beccari, G.; Bellazzini, M.; Fraternali, F.; Battaglia, G.; Perina, S.; Sollima, A.; Oosterloo, T. A.; Testa, V.; Galleti, S.

    2014-10-01

    Photometric catalogue of the dwarf irregular galaxy Sagittarius. The catalogue is obtained from deep V and I band wide field photometry from VIMOS at VLT. Only sources having at least six independent magnitude estimates per filter were included in this catalogue. The average and the standard error of the mean of the independent measures obtained from the different images were adopted as the final values of the instrumental magnitude and of the uncertainty on the relative photometry. The instrumental v and i magnitudes were transformed into the Johnson-Kron-Cousins V,I photometric system using more than 70 bright stars (V<22.5) in common with the publicly available HST Wide Field and Planetary Camera 2 (WFPC2) photometry by Holtzman et al. (2006ApJS..166..534H). The instrumental coordinates were transformed into J2000 Equatorial coordinates with 2nd degree polynomials, using more than 1000 stars in common with the GSC2.2 catalog. Please see Section 2.2 for details. (1 data file).

  11. The SNAP near infrared detectors

    SciTech Connect

    Tarle, G.; Akerlof, C.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Bercovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers, W.; Commins, E.D.; Day, C.; Deustua, S.; DiGennaro, R.; Ealet, Anne; Ellis, R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar, A.; Groom, D.; Harris, S.; Harvey, P.; Heetderks, H.; Holland, S.; Huterer, D.; Karcher, A.; Kim, A.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Lampton, M.; Levi, M.E.; Levin, D.; Linder, E.; Loken, S.; Malina, R.; Massey, R.; Miguel, R.; McKay, T.; McKee, S.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi, H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto, E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tomasch, A.; von der Lippe, H.; Vincent, R.; Walder, J.; Wang, G.

    2002-07-29

    The SuperNova/Acceleration Probe (SNAP) will measure precisely the cosmological expansion history over both the acceleration and deceleration epochs and thereby constrain the nature of the dark energy that dominates our universe today. The SNAP focal plane contains equal areas of optical CCDs and NIR sensors and an integral field spectrograph. Having over 150 million pixels and a field-of-view of 0.34 square degrees, the SNAP NIR system will be the largest yet constructed. With sensitivity in the range 0.9-1.7 {micro}m, it will detect Type Ia supernovae between z = 1 and 1.7 and will provide follow-up precision photometry for all supernovae. HgCdTe technology, with a cut-off tuned to 1.7 {micro}m, will permit passive cooling at 140 K while maintaining noise below zodiacal levels. By dithering to remove the effects of intrapixel variations and by careful attention to other instrumental effects, we expect to control relative photometric accuracy below a few hundredths of a magnitude. Because SNAP continuously revisits the same fields we will be able to achieve outstanding statistical precision on the photometry of reference stars in these fields, allowing precise monitoring of our detectors. The capabilities of the NIR system for broadening the science reach of SNAP are discussed.

  12. Bottled liquid explosive scanner by near infrared

    NASA Astrophysics Data System (ADS)

    Itozaki, Hideo

    2016-05-01

    A bottled liquid explosive scanner has been developed using near infrared technology for glass or PET bottles and ultrasound technology for metal cans. It has database of near infrared absorbance spectra and sound velocities of various liquids. Scanned liquids can be identified by using this database. This device has been certified by ECAC and installed at Japanese international airport.

  13. Near-infrared thermochromic diazapentalene dyes.

    PubMed

    Qian, Gang; Wang, Zhi Yuan

    2012-03-22

    A series of 2,5-diazapentalene containing dyes with tunable energy gaps are visible and near-infrared halochromic towards various acids and their protonated counterparts represent a new class of thermochromic materials with the near-infrared absorption being switched on at room temperature and off above 50 °C.

  14. Near-infrared Characterization of the Atmospheres of Alien Worlds

    NASA Astrophysics Data System (ADS)

    Croll, Bryce

    In this thesis I present near-infrared detections of the thermal emission of a number of hot Jupiters and likely transit depth differences from different wavelength observations of a super-Earth. I have pioneered "Staring Mode" using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope to achieve the most accurate photometry to-date in the near- infrared from the ground. I also discuss avenues that should allow one to achieve even more accurate photometry in the future. Using WIRCam on CFHT my collaborators and I have detected the thermal emission of the following hot Jupiters: TrES-2b and TrES-3b in Ks-band, WASP-12b in the J, H & Ks-bands, and WASP-3b in the Ks-band on two occasions. Near- infrared detections of the thermal emission of hot Jupiters are important, because the majority of these planets' blackbodies peak in this wavelength range; near-infrared detections allow us to obtain the most model-independent constraints on these planets' atmospheric characteristics, their temperature-pressure profiles with depth and an estimate of their bolometric luminosities. With these detections we are able to answer such questions as: how efficiently these planets redistribute heat to their nightsides, if they're being inflated by tidal heating, whether there's any evidence that one of these planets is precessing, and whether another experiences extreme weather and violent storms? My collaborators and I have also observed several transits of the super-Earth GJ 1214b. We find a deeper transit depth in one of our near-infrared bands than the other. This is likely indicative of a spectral absorption feature. For the differences in the transit depth to be as large as we observed, the atmosphere of GJ 1214b must have a large scale height, low mean molecular weight and thus have a hydrogen/helium dominated atmosphere. Given that other researchers have not found similar transit depth differences, we also discuss the most likely atmospheric makeup for this

  15. Near-infrared optical-resolution photoacoustic microscopy.

    PubMed

    Hai, Pengfei; Yao, Junjie; Maslov, Konstantin I; Zhou, Yong; Wang, Lihong V

    2014-09-01

    Compared with visible light (380-700 nm), near-infrared light (700-1400 nm) undergoes weaker optical attenuation in biological tissue; thus, it can penetrate deeper. Herein, we demonstrate near-infrared optical-resolution photoacoustic microscopy (NIR-OR-PAM) with 1046 nm illumination. A penetration depth of 3.2 mm was achieved in chicken breast tissue ex vivo using optical fluence within the American National Standards Institute (ANSI) limit (100  mJ/cm2). Beyond ∼0.6  mm deep in chicken breast tissue, NIR-OR-PAM has shown finer resolution than the visible counterpart with 570 nm illumination. The deep imaging capability of NIR-OR-PAM was validated in both a mouse ear and a mouse brain. NIR-OR-PAM of possible lipid contrast was explored as well.

  16. NEAR-INFRARED POLARIMETRY OF A NORMAL SPIRAL GALAXY VIEWED THROUGH THE TAURUS MOLECULAR CLOUD COMPLEX

    SciTech Connect

    Clemens, Dan P.; Cashman, L. R.; Pavel, M. D. E-mail: pavelmi@utexas.edu

    2013-03-15

    Few normal galaxies have been probed using near-infrared polarimetry, even though it reveals magnetic fields in the cool interstellar medium better than either optical or radio polarimetry. Deep H-band (1.6 {mu}m) linear imaging polarimetry toward Taurus serendipitously included the galaxy 2MASX J04412715+2433110 with adequate sensitivity and resolution to map polarization across nearly its full extent. The observations revealed the galaxy to be a steeply inclined ({approx}75 Degree-Sign ) disk type with a diameter, encompassing 90% of the Petrosian flux, of 4.2 kpc at a distance of 53 Mpc. Because the sight line passes through the Taurus Molecular Cloud complex, the foreground polarization needed to be measured and removed. The foreground extinction A{sub V} of 2.00 {+-} 0.10 mag and reddening E(H - K) of 0.125 {+-} 0.009 mag were also assessed and removed, based on analysis of Two Micron All Sky Survey, UKIRT Infrared Deep Sky Survey, Spitzer, and Wide-field Infrared Survey Explorer photometry using the Near-Infrared Color Excess, NICE-Revisited, and Rayleigh-Jeans Color Excess methods. Corrected for the polarized foreground, the galaxy polarization values range from 0% to 3%. The polarizations are dominated by a disk-parallel magnetic field geometry, especially to the northeast, while either a vertical field or single scattering of bulge light produces disk-normal polarizations to the southwest. The multi-kiloparsec coherence of the magnetic field revealed by the infrared polarimetry is in close agreement with short-wavelength radio synchrotron observations of edge-on galaxies, indicating that both cool and warm interstellar media of disk galaxies may be threaded by common magnetic fields.

  17. DEEP, WIDE-FIELD CCD PHOTOMETRY FOR THE OPEN CLUSTER NGC 3532

    SciTech Connect

    Clem, James L.; Landolt, Arlo U.; Hoard, D. W.; Wachter, Stefanie E-mail: landolt@phys.lsu.edu E-mail: wachter@ipac.caltech.edu

    2011-04-15

    We present the results of a deep, wide-field CCD survey for the open cluster NGC 3532. Our new BV(RI){sub c} photometry effectively covers a one square degree area and reaches an unprecedented depth of V {approx} 21 to reveal that NGC 3532 is a rich open cluster that harbors a large number of faint, low-mass stars. We employ a number of methods to reduce the impact of field star contamination in the cluster color-magnitude diagrams (CMDs), including supplementing our photometry with JHK{sub s} data from the 2MASS catalog. These efforts allow us to define a robust sample of candidate main-sequence stars suitable for a purely empirical determination of the cluster's parameters by comparing them to the well-established Hyades main sequence. Our results confirm previous findings that NGC 3532 lies fairly near to the Sun [(m - M){sub 0} = 8.46 {+-} 0.05; 492{sup +12}{sub -11} pc] and has an extremely low reddening for its location near the Galactic plane [E(B - V) = 0.028 {+-} 0.006]. Moreover, an age of {approx}300 Myr has been derived for the cluster by fitting a set of overshooting isochrones to the well-populated upper main sequence. This new photometry also extends faint enough to reach the cluster white dwarf sequence, as confirmed by our photometric recovery of eight spectroscopically identified members of the cluster. Using the location of these eight members, along with the latest theoretical cooling tracks, we have identified {approx}30 additional white dwarf stars in the [V, (B - V)] CMD that have a high probability of belonging to NGC 3532. Reassuringly, the age we derive from fitting white dwarf isochrones to the locus of these stars, 300 {+-} 100 Myr, is consistent with the age derived from the turnoff. Our analysis of the photometry also includes an estimation of the binary star fraction as well as a determination of the cluster's luminosity and mass functions.

  18. A DEEP UBVRI CCD PHOTOMETRY OF SIX OPEN STAR CLUSTERS IN THE GALACTIC ANTICENTER REGION

    SciTech Connect

    Lata, Sneh; Pandey, Anil K.; Kumar, Brijesh; Bhatt, Himali; Pace, Giancarlo; Sharma, Saurabh

    2010-02-15

    We present deep UBVRI CCD photometry of six open star clusters situated in the Galactic anticenter region (l{approx} 120-200 deg.). The sample includes three unstudied (Be 6, Be 77, King 17) and three partly studied open clusters (Be 9, NGC 2186, and NGC 2304). The fundamental parameters have been determined by comparing color-color and color-magnitude diagrams with the theoretical models. The structural parameters and morphology of the clusters were discussed on the basis of radial density profiles and isodensity contours, respectively. The isodensity contours show that all the clusters have asymmetric shapes. An investigation of structural parameters indicates that the evolution of core and corona of the clusters is mainly controlled by internal relaxation processes.

  19. SEDS: The Spitzer Extended Deep Survey. Survey Design, Photometry, and Deep IRAC Source Counts

    NASA Technical Reports Server (NTRS)

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Huang, J.-S.; Arendt, A.; Barmby, P.; Barro, G; Bell, E. F.; Bouwens, R.; Cattaneo, A.; Croton, D.; Dave, R.; Dunlop, J. S.; Egami, E.; Faber, S.; Finlator, K.; Grogin, N. A.; Guhathakurta, P.; Hernquist, L.; Hora, J. L.; Illingworth, G.; Kashlinsky, A; Koekmoer, A. M.; Koo, D. C.; Moseley, H.

    2013-01-01

    The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg(exp 2) to a depth of 26 AB mag (3sigma) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 micron. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 +/- 1.0 and 4.4 +/- 0.8 nW / square m/sr at 3.6 and 4.5 micron to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.

  20. SEDS: THE SPITZER EXTENDED DEEP SURVEY. SURVEY DESIGN, PHOTOMETRY, AND DEEP IRAC SOURCE COUNTS

    SciTech Connect

    Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Huang, J.-S.; Hernquist, L.; Hora, J. L.; Arendt, R.; Barmby, P.; Barro, G.; Faber, S.; Guhathakurta, P.; Bouwens, R.; Cattaneo, A.; Croton, D.; Dave, R.; Dunlop, J. S.; Egami, E.; Finlator, K.; Grogin, N. A.; and others

    2013-05-20

    The Spitzer Extended Deep Survey (SEDS) is a very deep infrared survey within five well-known extragalactic science fields: the UKIDSS Ultra-Deep Survey, the Extended Chandra Deep Field South, COSMOS, the Hubble Deep Field North, and the Extended Groth Strip. SEDS covers a total area of 1.46 deg{sup 2} to a depth of 26 AB mag (3{sigma}) in both of the warm Infrared Array Camera (IRAC) bands at 3.6 and 4.5 {mu}m. Because of its uniform depth of coverage in so many widely-separated fields, SEDS is subject to roughly 25% smaller errors due to cosmic variance than a single-field survey of the same size. SEDS was designed to detect and characterize galaxies from intermediate to high redshifts (z = 2-7) with a built-in means of assessing the impact of cosmic variance on the individual fields. Because the full SEDS depth was accumulated in at least three separate visits to each field, typically with six-month intervals between visits, SEDS also furnishes an opportunity to assess the infrared variability of faint objects. This paper describes the SEDS survey design, processing, and publicly-available data products. Deep IRAC counts for the more than 300,000 galaxies detected by SEDS are consistent with models based on known galaxy populations. Discrete IRAC sources contribute 5.6 {+-} 1.0 and 4.4 {+-} 0.8 nW m{sup -2} sr{sup -1} at 3.6 and 4.5 {mu}m to the diffuse cosmic infrared background (CIB). IRAC sources cannot contribute more than half of the total CIB flux estimated from DIRBE data. Barring an unexpected error in the DIRBE flux estimates, half the CIB flux must therefore come from a diffuse component.

  1. Near infrared lasers in flow cytometry.

    PubMed

    Telford, William G

    2015-07-01

    Technology development in flow cytometry has closely tracked laser technology, the light source that flow cytometers almost exclusively use to excite fluorescent probes. The original flow cytometers from the 1970s and 1980s used large water-cooled lasers to produce only one or two laser lines at a time. Modern cytometers can take advantage of the revolution in solid state laser technology to use almost any laser wavelength ranging from the ultraviolet to the near infrared. Commercial cytometers can now be equipped with many small solid state lasers, providing almost any wavelength needed for cellular analysis. Flow cytometers are now equipped to analyze 20 or more fluorescent probes simultaneously, requiring multiple laser wavelengths. Instrument developers are now trying to increase this number by designing fluorescent probes that can be excited by laser wavelength at the "edges" of the visible light range, in the near ultraviolet and near-infrared region. A variety of fluorescent probes have been developed that excite with violet and long wavelength ultraviolet light; however, the near-infrared range (660-800 nm) has yet seen only exploitation in flow cytometry. Fortunately, near-infrared laser diodes and other solid state laser technologies appropriate for flow cytometry have been in existence for some time, and can be readily incorporated into flow cytometers to accelerate fluorescent probe development. The near infrared region represents one of the last "frontiers" to maximize the number of fluorescent probes that can be analyzed by flow cytometry. In addition, near infrared fluorescent probes used in biomedical tracking and imaging could also be employed for flow cytometry with the correct laser wavelengths. This review describes the available technology, including lasers, fluorescent probes and detector technology optimal for near infrared signal detection.

  2. Stellar populations in edge-on galaxies from deep CCD surface photometry, 1: NGC 5907

    NASA Technical Reports Server (NTRS)

    Morrison, Heather L.; Boroson, Todd A.; Harding, Paul

    1994-01-01

    We present extremely deep charge coupled device (CCD) surface photometry of the edge-on Sc galaxy NGC 5907. Our data reach reliably to a surface brightness of R=27 mag/sq arcsec, some two magnitudes fainter than any previous work. We obtained this improvement using a 2048X2048 CCD with a wide (approximately 24 min) field, which made it possible to sky subtract directly from the galaxy frame, and by taking many dark sky flatfields. Our analysis of these data, using a full 2D model fitting procedure with a detailed error model, confirm the thin disk parameters of van der Kruit & Searle (1981). In particular, we confirm that the galaxy's disk has a radial cutoff and a constant scale height with radius. We find evidence for a stellar warp in this system, which has the same orientation as the H I warp. Our deep data also confirm that NGC 5907 has no thick disk. This suggests that theories of thick disk formation from star formation in the early stages of disk collapse, or by secular heating mechanisms, are unlikely to be correct, because they would predict that every galaxy would have a thick disk. Thick disk formation from the accretion of satellite galaxies is more likely.

  3. Note: Near infrared interferometric silicon wafer metrology.

    PubMed

    Choi, M S; Park, H M; Joo, K N

    2016-04-01

    In this investigation, two near infrared (NIR) interferometric techniques for silicon wafer metrology are described and verified with experimental results. Based on the transparent characteristic of NIR light to a silicon wafer, the fiber based spectrally resolved interferometry can measure the optical thickness of the wafer and stitching low coherence scanning interferometry can reconstruct entire surfaces of the wafer.

  4. Deep Washington photometry of inconspicuous star cluster candidates in the Large Magellanic Cloud

    SciTech Connect

    Choudhury, Samyaday; Subramaniam, Annapurni; Piatti, Andrés E.

    2015-02-01

    We present deep Washington photometry of 45 poorly populated star cluster candidates in the Large Magellanic Cloud (LMC). We have performed a systematic study to estimate the parameters of the cluster candidates by matching theoretical isochrones to the cleaned and dereddened cluster color–magnitude diagrams. We were able to estimate the basic parameters for 33 clusters, out of which 23 are identified as single clusters and 10 are found to be members of double clusters. The other 12 cluster candidates have been classified as possible clusters/asterisms. About 50% of the true clusters are in the 100–300 Myr age range, whereas some are older or younger. We have discussed the distribution of age, location, and reddening with respect to field, as well as the size of true clusters. The sizes and masses of the studied sample are found to be similar to that of open clusters in the Milky Way. Our study adds to the lower end of cluster mass distribution in the LMC, suggesting that the LMC, apart from hosting rich clusters, also has formed small, less massive open clusters in the 100–300 Myr age range.

  5. Feasibility of near-infrared markers for guiding surgical robots

    NASA Astrophysics Data System (ADS)

    Shademan, Azad; Dumont, Matthieu F.; Leonard, Simon; Krieger, Axel; Kim, Peter C. W.

    2013-09-01

    Automating surgery using robots requires robust visual tracking. The surgical environment often has poor light conditions where several organs have similar visual appearances. In addition, the field of view might be occluded by blood or tissue. In this paper, the feasibility of near-infrared (NIR) fluorescent marking and imaging for vision-based robot control is studied. The NIR region of the spectrum has several useful properties including deep tissue penetration. We study the optical properties of a clinically-approved NIR fluorescent dye, indocyanine green (ICG), with different concentrations and quantify image positioning error of ICG marker when obstructed by tissue.

  6. NEAR-INFRARED LINEAR POLARIZATION OF ULTRACOOL DWARFS

    SciTech Connect

    Zapatero Osorio, M. R.; Bejar, V. J. S.; Rebolo, R.; Acosta-Pulido, J. A.; Manchado, A.; Pena Ramirez, K.; Caballero, J. A. E-mail: vbejar@iac.es E-mail: jaa@iac.es E-mail: karla@iac.es E-mail: caballero@cab.inta-csic.es

    2011-10-10

    We report on near-infrared J- and H-band linear polarimetric photometry of eight ultracool dwarfs (two late-M, five L0-L7.5, and one T2.5) with known evidence for photometric variability due to dust clouds, anomalous red infrared colors, or low-gravity atmospheres. The polarimetric data were acquired with the LIRIS instrument on the William Herschel Telescope. We also provide mid-infrared photometry in the interval 3.4-24 {mu}m for some targets obtained with Spitzer and WISE, which has allowed us to confirm the peculiar red colors of five sources in the sample. We can impose modest upper limits of 0.9% and 1.8% on the linear polarization degree for seven targets with a confidence of 99%. Only one source, 2MASS J02411151-0326587 (L0), appears to be strongly polarized (P {approx} 3%) in the J band with a significance level of P/{sigma}{sub P} {approx} 10. The likely origin of its linearly polarized light and rather red infrared colors may reside in a surrounding disk with an asymmetric distribution of grains. Given its proximity (66 {+-} 8 pc), this object becomes an excellent target for the direct detection of the disk.

  7. [Near infrared light irradiator using halogen lamp].

    PubMed

    Ide, Yasuo

    2012-07-01

    The practical electric light bulb was invented by Thomas Alva Edison in 1879. Halogen lamp is the toughest and brightest electric light bulb. With light filter, it is used as a source of near infrared light. Super Lizer and Alphabeam are made as near infrared light irradiator using halogen lamp. The light emmited by Super Lizer is linear polarized near infrared light. The wave length is from 600 to 1,600 nm and strongest at about 1,000 nm. Concerning Super Lizer, there is evidence of analgesic effects and normalization of the sympathetic nervous system. Super Lizer has four types of probes. SG type is used for stellate ganglion irradiation. B type is used for narrow area irradiation. C and D types are for broad area irradiation. The output of Alphabeam is not polarized. The wave length is from 700 to 1,600 nm and the strongest length is about 1,000nm. Standard attachment is used for spot irradiation. Small attachment is used for stellate ganglion irradiation. Wide attachment is used for broad area irradiation. The effects of Alphabeam are thought to be similar to that of Super Lizer.

  8. Liquid explosive detection using near infrared LED

    NASA Astrophysics Data System (ADS)

    Itozaki, Hideo; Ito, Shiori; Sato-Akaba, Hideo; Miyato, Yuji

    2015-10-01

    A bottle scanner to detect liquid explosive has been developed using technologies of near infrared. Its detection rate of liquid explosive is quite high and its false alarm rate of safe liquids quite low. It uses a light source with wide spectrum such as a halogen lamp. Recently a variety of LEDs have been developed and some of them have near infrared spectrum. Here a near infrared LED is tested as a light source of the liquid explosive detector. Three infrared LEDs that have a main peak of spectrum at 901nm, 936nm, and 1028 nm have been used as a light source to scan liquids. Spectrum widths of these LEDs are quite narrow typically less than 100 nm. Ten typical liquids have been evaluated by these LEDs and the correlation coefficients of a spectrum by an LED and a tungsten lamp were more than 0.98. This experiment shows that the infrared LED can be used as a light source for the liquid scanner. An LED has some merits, such as long life of more than some ten thousand hours and small consumption electric power of less than 0.2 W. When the LED is used as a light source for the liquid scanner, it is also more compact and handy.

  9. Enhanced spatial near-infrared modulation of graphene-loaded perfect absorbers using plasmonic nanoslits.

    PubMed

    Cai, Yijun; Zhu, Jinfeng; Liu, Qing Huo; Lin, Timothy; Zhou, Jianyang; Ye, Longfang; Cai, Zhiping

    2015-12-14

    Modulating spatial near-infrared light for ultra-compact electro-optic devices is a critical issue in optical communication and imaging applications. To date, spatial near-infrared modulators based on graphene have been reported, but they showed limited modulation effects due to the relatively weak light-graphene interaction. In combination with graphene and metallic nanoslits, we design a kind of ultrathin near-infrared perfect absorber with enhanced spatial modulation effects and independence on a wide range of incident angles. The modulated spectral shift of central wavelength is up to 258.2 nm in the near-infrared range, which is more promising in applications than state-of-the-art devices. The modulation enhancement is attributed to the plasmonic nanoslit mode, in which the optical electric field is highly concentrated in the deep subwavelength scale and the light-graphene interaction is significantly strengthened. The physical insight is deeply revealed by a combination of equivalent circuit and electromagnetic field analysis. The design principles are not only crucial for spatial near-infrared modulators, but also provide a key guide for developing active near-infrared patch nanoantennas based on graphene.

  10. A YOUNG STELLAR CLUSTER WITHIN THE RCW41 H II REGION: DEEP NIR PHOTOMETRY AND OPTICAL/NIR POLARIMETRY

    SciTech Connect

    Santos, Fabio P.; Franco, Gabriel A. P.; Roman-Lopes, Alexandre E-mail: franco@fisica.ufmg.br

    2012-06-01

    The RCW41 star-forming region is embedded within the Vela Molecular Ridge, hosting a massive stellar cluster surrounded by a conspicuous H II region. Understanding the role of interstellar magnetic fields and studying the newborn stellar population is crucial to building a consistent picture of the physical processes acting on this kind of environment. We carried out a detailed study of the interstellar polarization toward RCW41 with data from an optical and near-infrared polarimetric survey. Additionally, deep near-infrared images from the 3.5 meter New Technology Telescope were used to study the photometric properties of the embedded young stellar cluster, revealing several YSO candidates. By using a set of pre-main-sequence isochrones, a mean cluster age in the range 2.5-5.0 million years was determined, and evidence of sequential star formation was revealed. An abrupt decrease in R-band polarization degree was noticed toward the central ionized area, probably due to low grain alignment efficiency caused by the turbulent environment and/or the weak intensity of magnetic fields. The distortion of magnetic field lines exhibits dual behavior, with the mean orientation outside the area approximately following the borders of the star-forming region and directed radially toward the cluster inside the ionized area, in agreement with simulations of expanding H II regions. The spectral dependence of polarization allowed a meaningful determination of the total-to-selective extinction ratio by fittings of the Serkowski relation. Furthermore, a large rotation of polarization angle as a function of wavelength was detected toward several embedded stars.

  11. A Young Stellar Cluster within the RCW41 H II Region: Deep NIR Photometry and Optical/NIR Polarimetry

    NASA Astrophysics Data System (ADS)

    Santos, Fábio P.; Roman-Lopes, Alexandre; Franco, Gabriel A. P.

    2012-06-01

    The RCW41 star-forming region is embedded within the Vela Molecular Ridge, hosting a massive stellar cluster surrounded by a conspicuous H II region. Understanding the role of interstellar magnetic fields and studying the newborn stellar population is crucial to building a consistent picture of the physical processes acting on this kind of environment. We carried out a detailed study of the interstellar polarization toward RCW41 with data from an optical and near-infrared polarimetric survey. Additionally, deep near-infrared images from the 3.5 meter New Technology Telescope were used to study the photometric properties of the embedded young stellar cluster, revealing several YSO candidates. By using a set of pre-main-sequence isochrones, a mean cluster age in the range 2.5-5.0 million years was determined, and evidence of sequential star formation was revealed. An abrupt decrease in R-band polarization degree was noticed toward the central ionized area, probably due to low grain alignment efficiency caused by the turbulent environment and/or the weak intensity of magnetic fields. The distortion of magnetic field lines exhibits dual behavior, with the mean orientation outside the area approximately following the borders of the star-forming region and directed radially toward the cluster inside the ionized area, in agreement with simulations of expanding H II regions. The spectral dependence of polarization allowed a meaningful determination of the total-to-selective extinction ratio by fittings of the Serkowski relation. Furthermore, a large rotation of polarization angle as a function of wavelength was detected toward several embedded stars. Based on observations collected at the European Southern Observatory (La Silla, Chile), National Optical Astronomy Observatory (CTIO, Chile), and Observatório do Pico dos Dias, operated by Laboratório Nacional de Astrofísica (LNA/MCT, Brazil).

  12. A near-infrared genetically targetable and activatable photosensitizer

    PubMed Central

    He, Jianjun; Wang, Yi; Missinato, Maria A.; Onuoha, Ezenwa; Perkins, Lydia A.; Watkins, Simon C.; St. Croix, Claudette M.; Tsang, Michael; Bruchez, Marcel P.

    2016-01-01

    Upon illumination, photosensitizer molecules produce reactive oxygen species (ROS) that can be utilized for functional manipulation of living cells, including protein inactivation, targeted damage introduction, and cellular ablation. Photosensitizers used to date have been either exogenous, resulting in delivery and removal challenges, or genetically encoded proteins that form or bind a native photosensitizing molecule, resulting in a constitutively active photosensitizer inside the cell. By binding a heavy-atom substituted fluorogenic dye with a genetically encoded Fluorogen Activating Protein (FAP), we demonstrate an ‘on-demand’ activated photosensitizer that produces singlet oxygen and fluorescence only when FAP-bound and activated with near infrared light. This Targeted and Activated Photosensitizer (TAPs) approach enables protein inactivation and targeted cell killing in cultured cells and rapid targeted lineage ablation in living larval and adult zebrafish. The near-infrared excitation and emission of this FAP-TAPs photosensitizer module provides a new spectral range for photosensitizer proteins, useful for imaging, manipulation and cellular ablation deep within living organisms. PMID:26808669

  13. Near-infrared stimulation on globus pallidus and subthalamus

    NASA Astrophysics Data System (ADS)

    Yoo, Minsu; Koo, Ho; Kim, Minsun; Kim, Hyoung-Ihl; Kim, Sohee

    2013-12-01

    Near-infrared stimulation (NIS) is an emerging technique used to evoke action potentials in nervous systems. Its efficacy of evoking action potentials has been demonstrated in different nerve tissues. However, few studies have been performed using NIS to stimulate the deep brain structures, such as globus pallidus (GP) and subthalamic nucleus (STN). Male Sprague-Dawley rats were randomly divided into GP stimulation group (n=11) and STN stimulation group (n=6). After introducing optrodes stereotaxically into the GP or STN, we stimulated neural tissue for 2 min with continuous near-infrared light of 808 nm while varying the radiant exposure from 40 to 10 mW. The effects were investigated with extracellular recordings and the temperature rises at the stimulation site were also measured. NIS was found to elicit excitatory responses in eight out of 11 cases (73%) and inhibitory responses in three cases in the GP stimulation group, whereas it predominantly evoked inhibitory responses in seven out of eight cases (87.5%) and an excitatory response in one case in STN stimulation group. Only radiation above 20 mW, accompanying temperature increases of more than 2°C, elicited a statistically significant neural response (p<0.05). The responsiveness to NIS was linearly dependent on the power of radiation exposure.

  14. Near-Infrared Spectra of Uranian Satellites

    NASA Astrophysics Data System (ADS)

    Venturini, C. C.; Lynch, D. K.; Rudy, R. J.; Mazuk, S.; Puetter, R. C.

    2001-05-01

    We present 0.8 to 2.5 micron spectra taken on June 21 & 22, 1998 UT of the Uranian satellites Miranda, Titania, Ariel, Oberon, and Umbriel. The spectra were taken using The Aerospace Corporation's Near-Infrared Imaging Spectragraph (NIRIS) on the University of California's Lick Observatory 3 meter Shane telescope. These spectra will be compared with previous work including Brown, R.H. and Cruikshank, D.P. (1983) as well as more recent spectra and analysis by Grundy, W. et al. (1999). Support for this research was provided by The Aerospace Corporation's Independent Research and Development Program.

  15. Near-infrared scintillation of liquid argon

    SciTech Connect

    Alexander, T.; Escobar, C. O.; Lippincott, W. H.; Rubinov, P.

    2016-03-03

    Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7 $\\mu$m < $\\lambda$; < 1.5$\\mu$m). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab.

  16. Near-infrared spectroscopy of dark asteroids.

    PubMed

    Barucci, M A; Lazzarin, M; Owen, T; Barbieri, C; Fulchignoni, M

    1994-08-01

    Near-infrared (J, H and K bands) spectra of nine dark asteroids (chosen among a sample of supposed primitive objects between C and D classes) have been obtained at the Mauna Kea Observatory (Hawaii) with the 2.2-m telescope using KSPEC as spectrograph. The aim of this work was to search for evidence of the presence of organic materials in these objects as found in other planetary bodies as 5145 Pholus, and in some cometary nuclei. A careful analysis of the data has revealed flat or slightly redder spectra than the solar one for all observed asteroids. No evidence of distinct absorption features was found.

  17. AKARI NEAR-INFRARED SPECTROSCOPY OF LUMINOUS INFRARED GALAXIES

    SciTech Connect

    Lee, Jong Chul; Lee, Myung Gyoon; Hwang, Ho Seong

    2012-09-01

    We present the AKARI near-infrared (NIR; 2.5-5 {mu}m) spectroscopic study of 36 (ultra)luminous infrared galaxies ((U)LIRGs) at z = 0.01-0.4. We measure the NIR spectral features including the strengths of 3.3 {mu}m polycyclic aromatic hydrocarbon emission and hydrogen recombination lines (Br{alpha} and Br{beta}), optical depths at 3.1 and 3.4 {mu}m, and NIR continuum slope. These spectral features are used to identify optically elusive, buried active galactic nuclei (AGNs). We find that half of the (U)LIRGs optically classified as non-Seyferts show AGN signatures in their NIR spectra. Using a combined sample of (U)LIRGs with NIR spectra in the literature, we measure the contribution of buried AGNs to the infrared luminosity from the spectral energy distribution fitting to the IRAS photometry. The contribution of these buried AGNs to the infrared luminosity is 5%-10%, smaller than the typical AGN contribution of (U)LIRGs including Seyfert galaxies (10%-40%). We show that NIR continuum slopes correlate well with WISE [3.4]-[4.6] colors, which would be useful for identifying a large number of buried AGNs using the WISE data.

  18. Low-Resolution Near-infrared Stellar Spectra Observed by the Cosmic Infrared Background Experiment (CIBER)

    NASA Astrophysics Data System (ADS)

    Kim, Min Gyu; Lee, Hyung Mok; Arai, Toshiaki; Bock, James; Cooray, Asantha; Jeong, Woong-Seob; Kim, Seong Jin; Korngut, Phillip; Lanz, Alicia; Lee, Dae Hee; Lee, Myung Gyoon; Matsumoto, Toshio; Matsuura, Shuji; Nam, Uk Won; Onishi, Yosuke; Shirahata, Mai; Smidt, Joseph; Tsumura, Kohji; Yamamura, Issei; Zemcov, Michael

    2017-02-01

    We present near-infrared (0.8–1.8 μm) spectra of 105 bright ({m}J < 10) stars observed with the low-resolution spectrometer on the rocket-borne Cosmic Infrared Background Experiment. As our observations are performed above the Earth's atmosphere, our spectra are free from telluric contamination, which makes them a unique resource for near-infrared spectral calibration. Two-Micron All-Sky Survey photometry information is used to identify cross-matched stars after reduction and extraction of the spectra. We identify the spectral types of the observed stars by comparing them with spectral templates from the Infrared Telescope Facility library. All the observed spectra are consistent with late F to M stellar spectral types, and we identify various infrared absorption lines.

  19. Precise Near-Infrared Radial Velocities

    NASA Astrophysics Data System (ADS)

    Plavchan, Peter; Gao, P.; Bottom, M.; Davison, C.; Mills, S.; Ciardi, D. R.; Brinkworth, C.; Tanner, A. M.; Beichman, C. A.; Catanzarite, J.; Crawford, S.; Wallace, J.; Mennesson, B.; Johnson, J. A.; White, R. J.; Anglada-Escudé, G.; von Braun, K.; Walp, B.; Vasisht, G.; Kane, S. R.; Prato, L. A.; NIRRVs

    2014-01-01

    We present precise radial velocity time-series from a 2.3 micron pilot survey to detect exoplanets around red, low mass, and young stars. We use the CSHELL spectrograph with an isotopic methane absorption gas cell for common optical path relative wavelength calibration at the NASA InfraRed Telescope Facility. We present an overview of our Nelder-Mead simplex optimization pipeline for extracting radial velocities. We will also present first light data at 1.6 microns from a near-infrared fiber scrambler used in tandem with our gas cell and CSHELL at IRTF. The fiber scrambler makes use of non-circular core fibers to stabilize the illumination of the slit and echelle grating against changes in seeing, focus, guiding and other sources of systematic radial velocity noise, complementing the wavelength calibration of a gas cell.

  20. Precise Near-Infrared Radial Velocities

    NASA Astrophysics Data System (ADS)

    Plavchan, Peter; Gao, Peter; Gagne, Jonathan; Furlan, Elise; Brinkworth, Carolyn; Bottom, Michael; Tanner, Angelle; Anglada-Escude, Guillem; White, Russel; Davison, Cassy; Mills, Sean; Beichman, Chas; Johnson, John Asher; Ciardi, David; Wallace, Kent; Mennesson, Bertrand; Vasisht, Gautam; Prato, Lisa; Kane, Stephen; Crawford, Sam; Crawford, Tim; Sung, Keeyoon; Drouin, Brian; Lin, Sean; Leifer, Stephanie; Catanzarite, Joe; Henry, Todd; von Braun, Kaspar; Walp, Bernie; Geneser, Claire; Ogden, Nick; Stufflebeam, Andrew; Pohl, Garrett; Regan, Joe

    2016-01-01

    We present the results of two 2.3 μm near-infrared (NIR) radial velocity (RV) surveys to detect exoplanets around 36 nearby and young M dwarfs. We use the CSHELL spectrograph (R ~ 46,000) at the NASA InfraRed Telescope Facility (IRTF), combined with an isotopic methane absorption gas cell for common optical path relative wavelength calibration. We have developed a sophisticated RV forward modeling code that accounts for fringing and other instrumental artifacts present in the spectra. With a spectral grasp of only 5 nm, we are able to reach long-term radial velocity dispersions of ~20-30 m s-1 on our survey targets.

  1. Detection of bottled explosives by near infrared

    NASA Astrophysics Data System (ADS)

    Itozaki, Hideo; Sato-Akaba, Hideo

    2013-10-01

    Bottled liquids are not allowed through the security gate in the airport, because liquid explosives have been used by the terrorists. However, passengers have a lot of trouble if they cannot bring their own bottles. For example, a mother would like to carry her own milk in the airplane for her baby. Therefore the detection technology of liquid explosives should be developed as soon as possible. This paper shows that near infrared spectroscopy can detect bottled explosives quickly. The transmission method cannot deal with milk in the sense of liquid inspection. Here we examined the reflection method to the test of milk. The inspection method with light cannot make test for the metal can. We also use ultrasonic method to check metal can simultaneously in order to expand test targets.

  2. Near-infrared light photoacoustic ophthalmoscopy

    PubMed Central

    Liu, Tan; Wei, Qing; Song, Wei; Burke, Janice M.; Jiao, Shuliang; Zhang, Hao F.

    2012-01-01

    We achieved photoacoustic ophthalmoscopy (PAOM) imaging of the retina with near-infrared (NIR) light illumination. A PAOM imaging system with dual-wavelength illumination at 1064 nm and 532 nm was built. We compared in vivo imaging results of both albino and pigmented rat eyes at the two wavelengths. The results show that the bulk optical absorption of the retinal pigment epithelium (RPE) is only slightly higher than that of the retinal vessels at 532 nm while it becomes more than an order of magnitude higher than that of the retinal vessels at 1064 nm. These studies suggest that although visible light illumination is suitable for imaging both the retinal vessels and the RPE, NIR light illumination, being more comfortable to the eye, is better suited for RPE melanin related investigations and diagnoses. PMID:22574266

  3. Near-Infrared Intraoperative Chemiluminescence Imaging.

    PubMed

    Büchel, Gabriel E; Carney, Brandon; Shaffer, Travis M; Tang, Jun; Austin, Christine; Arora, Manish; Zeglis, Brian M; Grimm, Jan; Eppinger, Jörg; Reiner, Thomas

    2016-09-20

    Intraoperative imaging technologies recently entered the operating room, and their implementation is revolutionizing how physicians plan, monitor, and perform surgical interventions. In this work, we present a novel surgical imaging reporter system: intraoperative chemiluminescence imaging (ICI). To this end, we have leveraged the ability of a chemiluminescent metal complex to generate near-infrared light upon exposure to an aqueous solution of Ce(4+) in the presence of reducing tissue or blood components. An optical camera spatially resolves the resulting photon flux. We describe the construction and application of a prototype imaging setup, which achieves a detection limit as low as 6.9 pmol cm(-2) of the transition-metal-based ICI agent. As a proof of concept, we use ICI for the in vivo detection of our transition metal tracer following both systemic and subdermal injections. The very high signal-to-noise ratios make ICI an interesting candidate for the development of new intraoperative imaging technologies.

  4. Evaluation of a near-infrared photomultiplier

    NASA Technical Reports Server (NTRS)

    Evans, W. E.

    1978-01-01

    A high performance near infrared sensitive photomultiplier tube was procured and evaluated with emphasis on those characteristics affecting its use over the very large amplitude range of signals encountered by an airborne lidar intended for mapping the distribution of stratospheric aerosols. A cathode quantum efficiency of 4.3 percent at 1.06 micrometer wavelength and a background count of less than 10,000 per second were realized. It is recommended that the tube be stored and operated at a temperature near -20 C, or cooler. Performance was found acceptable for the application in both pulse counting and analog modes, but careful design, probably including dynamic gain control, will be required to effectively utilize both modes on the same lidar shot.

  5. Near Infrared (nir) Imaging for Nde

    NASA Astrophysics Data System (ADS)

    Diamond, G. G.; Pallav, P.; Hutchins, D. A.

    2008-02-01

    A novel application of near infrared (NIR) signals is presented, which can be used to provide images of many different materials and objects. It is effectively a very low cost non-ionising alternative to many applications currently being investigated using electromagnetic waves at other frequencies, such as THz and X-ray imaging. This alternative technique can be realised by very simple and inexpensive electronics and is inherently far more portable and easy to use. Transmission imaging results from this technique are presented from examples industrial quality control, food inspection and various security applications, and the results compared to existing techniques. In addition, this technique can be used in through-transmission mode on biological and medical samples, and images are presented that differentiate between not only flesh and bone, but also various types of soft tissue.

  6. Near Infrared Astronomical Observing During the Daytime

    NASA Astrophysics Data System (ADS)

    Tinn Chee Jim, Kevin; Pier, Edward Alan; Cognion, Rita L.

    2015-08-01

    Ground-based, near-infrared astronomy has been mostly restriced to nighttime observing with occasional, bright solar system objects observed during the daytime. But for astronomical phenomena that are time-varying on timescales of less than a day, it would be advantageous to be able to gather data during the day and night. We explore some of the limitations of observing in the J, H, and K bands during the daytime. Atmospheric radiative transfer simulations show that K is the optimal common astronomical filter for daytime observations on Mauna Kea, but the J and H filters can also be used. Observations from Mauna Kea show that it is possible to observe objects at least as faint as K=15.5 during the early afternoon, with photometric accuracies only slightly worse than those obtained at night.

  7. Near-infrared absorptions of monomethylhydrazine

    NASA Technical Reports Server (NTRS)

    Murray, Mark; Kurtz, Joe

    1993-01-01

    The peak absorption coefficients for two near-infrared absorptions of monomethylhydrazine, CH3-N2H3, (MMH) were measured. Absorption bands located at 1.524 micrometers (6560/cm), 1.557 micrometers (6423/cm), and 1.583 micrometers (6316/cm) are assigned to the Delta upsilon = 2 overtones of the infared N-H stretching fundamentals at 3317, 3245 and 3177/cm. An absorption band located at 1.04 micrometers (9620 +/- 100/cm) is assigned to the Delta upsilon = 3 overtone of one of these fundamentals. The peak absorption coefficients (alpha(sub 10)) at 1.524 micrometers (6560 +/- 20/cm) and 1.04 micrometers (9620 +/- 100/cm) are 31 x 10(exp -3) and 0.97 x 10(exp -3)/(cm atm), respectively. Uncertainties in these coefficients were estimated to be less than +/- 20% due primarily to uncertainties in the partial vapor pressure of MMH.

  8. SPIRou -A Near-Infrared Spectropolarimeter @ CFHT

    NASA Astrophysics Data System (ADS)

    Malo, Lison; Moutou, Claire; Artigau, Etienne; Delfosse, Xavier; Donati, Jean-François; Doyon, Rene; Fouqué, Pascal; Morin, Julien; Martioli, Eder

    2015-12-01

    SPIRou is a near-infrared spectropolarimeter and a high-precision velocimeter optimized for both the detection and characterization of terrestrial planets orbiting nearby low-mass stars, and the study of the impact of magnetic field on the star-planet formation. The spectrograph is designed to record the whole near-infrared spectrum simultaneously in either circular or linear polarization and to reach a RV precision of 1 m/s at a resolving power of 75,000. It will be use to carry out the "SPIRou Legacy Survey" targeting two science objectives (habitable terrestrial planet detection & magnetic field impact on star-planet formation) and is intended to provide the community with an extensive, homogenous, well characterized and high-quality data. SPIRou is expected to make a major breakthrough in the field of telluric planets in the habitable zone of cool stars. Once implemented at CFHT in 2017, SPIRou is expected to be used extensively by the astronomical community - supporting in particular space missions such as TESS, JWST and PLATO. In this presentation, I will focus on the impact of the SPIRou future observing programs in the field of exoplanets: 1) the radial-velocity survey, its target selection of cool dwarfs, strategy and expectations; 2) the follow-up characterization of transiting candidates; 3) the search for giant planets around very young stars; 4) the importance of spectropolarimetry to filter out the intrinsic jitter of target stars at the sub m/s level; 5) the anticipated role in preparing further exoplanet characterization missions.

  9. CANDELS Multi-wavelength Catalogs: Source Identification and Photometry in the CANDELS COSMOS Survey Field

    NASA Astrophysics Data System (ADS)

    Nayyeri, H.; Hemmati, S.; Mobasher, B.; Ferguson, H. C.; Cooray, A.; Barro, G.; Faber, S. M.; Dickinson, M.; Koekemoer, A. M.; Peth, M.; Salvato, M.; Ashby, M. L. N.; Darvish, B.; Donley, J.; Durbin, M.; Finkelstein, S.; Fontana, A.; Grogin, N. A.; Gruetzbauch, R.; Huang, K.; Khostovan, A. A.; Kocevski, D.; Kodra, D.; Lee, B.; Newman, J.; Pacifici, C.; Pforr, J.; Stefanon, M.; Wiklind, T.; Willner, S. P.; Wuyts, S.; Castellano, M.; Conselice, C.; Dolch, T.; Dunlop, J. S.; Galametz, A.; Hathi, N. P.; Lucas, R. A.; Yan, H.

    2017-01-01

    We present a multi-wavelength photometric catalog in the COSMOS field as part of the observations by the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. The catalog is based on Hubble Space Telescope Wide Field Camera 3 (HST/WFC3) and Advanced Camera for Surveys observations of the COSMOS field (centered at R.A.: {10}{{h}}{00}{{m}}{28}{{s}}, Decl.: +02^\\circ 12\\prime {21}\\prime\\prime ). The final catalog has 38671 sources with photometric data in 42 bands from UV to the infrared (∼ 0.3{--}8 μ {{m}}). This includes broadband photometry from HST, CFHT, Subaru, the Visible and Infrared Survey Telescope for Astronomy, and Spitzer Space Telescope in the visible, near-infrared, and infrared bands along with intermediate- and narrowband photometry from Subaru and medium-band data from Mayall NEWFIRM. Source detection was conducted in the WFC3 F160W band (at 1.6 μm) and photometry is generated using the Template FITting algorithm. We further present a catalog of the physical properties of sources as identified in the HST F160W band and measured from the multi-band photometry by fitting the observed spectral energy distributions of sources against templates.

  10. The S28H mutation on mNeptune generates a brighter near-infrared monomeric fluorescent protein with improved quantum yield and pH-stability.

    PubMed

    Li, Zhao-Yang; Wang, Dian-Bing; Zhang, Zhi-Ping; Bi, Li-Jun; Cui, Zong-Qiang; Deng, Jiao-Yu; Zhang, Xian-En

    2014-09-01

    For living deep-tissue imaging, the optical window favorable for light penetration is in near-infrared wavelengths, which requires fluorescent proteins with emission spectra in the near-infrared region. Here, we report that a single mutant Ser28His of mNeptune with a near-infrared (≥650 nm) emission maxima of 652 nm is found to improve the brightness, photostability, and pH stability when compared with its parental protein mNeptune, while it remains as a monomer, demonstrating that there is still plenty of room to improve the performance of the existing near infrared fluorescence proteins by directed evolution.

  11. NIMBUS: A Near-Infrared Multi-Band Ultraprecise Spectroimager for SOFIA

    NASA Technical Reports Server (NTRS)

    McElwain, Michael W.; Mandell, Avi; Woodgate, Bruce E.; Spiegel, David S.; Madhusudhan, Nikku; Amatucci, Edward; Blake, Cullen; Budinoff, Jason; Burgasser, Adam; Burrows, Adam; Clampin, Mark C.; Conroy, Charlie; Deming, L. Drake; Dunham, Edward; Foltz, Roger; Gong, Qian; Knutson, Heather; Muench, Theodore; Murray-Clay, Ruth; Peabody, Hume; Rauscher, Bernard J.; Rinehart, Stephen A.; Villanueva, Geronimo

    2012-01-01

    We present a new and innovative near-infrared multi-band ultraprecise spectroimager (NIMBUS) for SOFIA. This instrument will enable many exciting observations in the new age of precision astronomy. This optical design splits the beam into 8 separate spectral bandpasses, centered around key molecular bands from 1 to 4 microns. Each spectral channel has a wide field of view for simultaneous observations of a reference star that can decorrelate time-variable atmospheric and optical assembly effects, allowing the instrument to achieve ultraprecise photometry for a wide variety of astrophysical sources

  12. HUBBLE SPACE TELESCOPE/NEAR-INFRARED CAMERA AND MULTI-OBJECT SPECTROMETER OBSERVATIONS OF THE GLIMPSE9 STELLAR CLUSTER

    SciTech Connect

    Messineo, Maria; Figer, Donald F.; Davies, Ben; Trombley, Christine; Kudritzki, R. P.; Rich, R. Michael; MacKenty, John

    2010-01-10

    We present Hubble Space Telescope/Near-Infrared Camera and Multi-Object Spectrometer photometry, and low-resolution K-band spectra of the GLIMPSE9 stellar cluster. The newly obtained color-magnitude diagram shows a cluster sequence with H - K{sub S} = approx1 mag, indicating an interstellar extinction A{sub K{sub s}} = 1.6 +- 0.2 mag. The spectra of the three brightest stars show deep CO band heads, which indicate red supergiants with spectral type M1-M2. Two 09-B2 supergiants are also identified, which yield a spectrophotometric distance of 4.2 +- 0.4 kpc. Presuming that the population is coeval, we derive an age between 15 and 27 Myr, and a total cluster mass of 1600 +- 400 M{sub sun}, integrated down to 1 M{sub sun}. In the vicinity of GLIMPSE9 are several H II regions and supernova remnants, all of which (including GLIMPSE9) are probably associated with a giant molecular cloud (GMC) in the inner galaxy. GLIMPSE9 probably represents one episode of massive star formation in this GMC. We have identified several other candidate stellar clusters of the same complex.

  13. Bioprocess monitoring using near-infrared spectroscopy.

    PubMed

    Suehara, Ken-ichiro; Yano, Takuo

    2004-01-01

    Near-infrared spectroscopy (NIR) is a nondestructive analytical technique that has been used for simultaneous prediction of the concentrations of several substrates, products and constructs in mixtures sampled from fermentation processes. In this chapter, we discuss applications of NIR for the monitoring of bioprocesses involving rice vinegar, compost, glycolipid, L-glutamic acid, lactic acid fermentation, mushroom cultivation, and Koji production. This includes detailed discussion of applications of NIR to process management of rice vinegar fermentation and compost fermentation. In the present study, absorbance at wavelengths between 400 and 2500 nm was measured at 2 nm intervals. To obtain calibration equations, multiple linear regression (MLR) was performed on NIR spectral data and conventional analysis values of a calibration sample set. To validate these calibration equations, they were used to calculate concentrations of a prediction sample set, which were then compared with concentrations measured by conventional methods. There was excellent agreement between the results of the conventional method and those of the NIR method, when both were used to analyze culture broth of rice vinegar fermentation and solid-state fermented compost. These results indicate that NIR is a useful method for monitoring and control of bioprocesses.

  14. Near-infrared fluorophores as biomolecular probes

    NASA Astrophysics Data System (ADS)

    Patonay, Gabor; Beckford, Garfield; Strekowski, Lucjan; Henary, Maged; Merid, Yonathan

    2010-02-01

    Near-Infrared (NIR) fluorescence has been valuable in analytical and bioanalytical chemistry. NIR probes and labels have been used for several applications, including hydrophobicity of protein binding sites, DNA sequencing, immunoassays, CE separations, etc. The NIR region (700-1100 nm) has advantages for the spectroscopist due to the inherently lower background interference from the biological matrix and the high molar absorptivities of NIR chromophores. During the studies we report here several NIR dyes were prepared to determine the role of the hydrophobicity of NIR dyes and their charge in binding to amino acids and proteins, e.g., serum albumins. We synthesized NIR dye homologs containing the same chromophore but substituents of varying hydrophobicity. Hydrophobic moieties were represented by alkyl and aryl groups. These NIR dyes of varying hydrophobicity exhibited varying degrees of H-aggregation in aqueous solution indicating that the degree of H-aggregation could be used as an indicator to predict binding characteristics to serum albumins. In order to understand what factors may be important in the binding process, spectral behavior of these varying hydrophobicity dyes were examined in the presence of amino acids. Typical dye structures that exhibit large binding constants to biomolecules were compared in order to optimize applications utilizing non-covalent interactions.

  15. The Euclid near-infrared calibration source

    NASA Astrophysics Data System (ADS)

    Holmes, Rory; Bizenberger, Peter; Krause, Oliver; Schweitzer, Mario; Glauser, Adrian M.

    2010-07-01

    The Euclid dark energy mission is currently competing in ESA's Cosmic Vision program. Its imaging instrument, which has one visible and one infrared channel, will survey the entire extragalactic sky during the 5 year mission. The near-infrared imaging photometer (NIP) channel, operating in the ~0.92 - 2.0 μm spectral range, will be used in conjunction with the visible imaging channel (VIS) to constrain the nature of dark energy and dark matter. To meet the stringent overall photometric requirement, the NIP channel requires a dedicated on-board flat-field source to calibrate the large, 18 detector focal plane. In the baseline concept a 170 mm Spectralon diffuser plate, mounted to a pre-existing shutter mechanism outside the channel, is used as a flat-field calibration target, negating the need for an additional single-point-failure mechanism. The 117 × 230 mm focal plane will therefore be illuminated through all of the channel's optical elements and will allow flat-field measurements to be taken in all wavelength bands. A ring of low power tungsten lamps, with custom reflecting elements optimized for optical performance, will be used to illuminate the diffuser plate. This paper details the end-to-end optical simulations of this concept, a potential mechanical implementation and the initial tests of the proposed key components.

  16. Near-Infrared Diffuse Optical Tomography

    PubMed Central

    Hielscher, A. H.; Bluestone, A. Y.; Abdoulaev, G. S.; Klose, A. D.; Lasker, J.; Stewart, M.; Netz, U.; Beuthan, J.

    2002-01-01

    Diffuse optical tomography (DOT) is emerging as a viable new biomedical imaging modality. Using near-infrared (NIR) light, this technique probes absorption as well as scattering properties of biological tissues. First commercial instruments are now available that allow users to obtain cross-sectional and volumetric views of various body parts. Currently, the main applications are brain, breast, limb, joint, and fluorescence/bioluminescence imaging. Although the spatial resolution is limited when compared with other imaging modalities, such as magnetic resonance imaging (MRI) or X-ray computerized tomography (CT), DOT provides access to a variety of physiological parameters that otherwise are not accessible, including sub-second imaging of hemodynamics and other fast-changing processes. Furthermore, DOT can be realized in compact, portable instrumentation that allows for bedside monitoring at relatively low cost. In this paper, we present an overview of current state-of-the -art technology, including hardware and image-reconstruction algorithms, and focus on applications in brain and joint imaging. In addition, we present recent results of work on optical tomographic imaging in small animals. PMID:14646043

  17. Near infrared photoimmunotherapy for lung metastases

    PubMed Central

    Sato, Kazuhide; Nagaya, Tadanobu; Mitsunaga, Makoto; Choyke, Peter L.; Kobayashi, Hisataka

    2015-01-01

    Lung metastases are a leading cause of cancer related deaths; nonetheless current treatments are limited. Near infrared photoimmunotherapy (NIR-PIT) is a new cancer treatment that combines the specificity of intravenously injected antibodies that target tumors with the toxicity induced by photosensitizers activated by NIR-light. Herein, we demonstrate the efficacy of NIR-PIT in a mouse model of lung metastases. Experiments were conducted with a HER2, luciferase and GFP expressing cell line (3T3/HER2-luc-GFP). An antibody-photosensitizer conjugate (APC) consisting of trastuzumab and a phthalocyanine dye, IRDye-700DX, was synthesized. In vitro NIR-PIT-induced cytotoxicity was light dose dependent. With 3D culture, repeated NIR-PIT could eradicate entire spheroids. In vivo anti-tumor effects of NIR-PIT included significant reductions in both tumor volume (p = 0.0141 vs. APC) and bioluminescence image (BLI) (p = 0.0086 vs. APC) in the flank model, and prolonged survival (p < 0.0001). BLI demonstrated a significant reduction in lung metastases volume (p = 0.0117 vs. APC). Multiple NIR-PIT doses significantly prolonged survival in the lung metastases model (p < 0.0001). These results suggested that NIR-PIT is a potential new therapy for the local control of lung metastases. PMID:26021765

  18. Combining Dark Energy Survey Science Verification data with near-infrared data from the ESO VISTA Hemisphere Survey

    NASA Astrophysics Data System (ADS)

    Banerji, Manda; Jouvel, S.; Lin, H.; McMahon, R. G.; Lahav, O.; Castander, F. J.; Abdalla, F. B.; Bertin, E.; Bosman, S. E.; Carnero, A.; Kind, M. Carrasco; da Costa, L. N.; Gerdes, D.; Gschwend, J.; Lima, M.; Maia, M. A. G.; Merson, A.; Miller, C.; Ogando, R.; Pellegrini, P.; Reed, S.; Saglia, R.; Sánchez, C.; Allam, S.; Annis, J.; Bernstein, G.; Bernstein, J.; Bernstein, R.; Capozzi, D.; Childress, M.; Cunha, Carlos E.; Davis, T. M.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Findlay, J.; Finley, D. A.; Flaugher, B.; Frieman, J.; Gaztanaga, E.; Glazebrook, K.; González-Fernández, C.; Gonzalez-Solares, E.; Honscheid, K.; Irwin, M. J.; Jarvis, M. J.; Kim, A.; Koposov, S.; Kuehn, K.; Kupcu-Yoldas, A.; Lagattuta, D.; Lewis, J. R.; Lidman, C.; Makler, M.; Marriner, J.; Marshall, Jennifer L.; Miquel, R.; Mohr, Joseph J.; Neilsen, E.; Peoples, J.; Sako, M.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sevilla, I.; Sharp, R.; Soares-Santos, M.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Tucker, D.; Uddin, S. A.; Wechsler, R.; Wester, W.; Yuan, F.; Zuntz, J.

    2015-01-01

    We present the combination of optical data from the Science Verification phase of the Dark Energy Survey (DES) with near-infrared (NIR) data from the European Southern Observatory VISTA Hemisphere Survey (VHS). The deep optical detections from DES are used to extract fluxes and associated errors from the shallower VHS data. Joint seven-band (grizYJK) photometric catalogues are produced in a single 3 sq-deg dedicated camera field centred at 02h26m-04d36m where the availability of ancillary multiwavelength photometry and spectroscopy allows us to test the data quality. Dual photometry increases the number of DES galaxies with measured VHS fluxes by a factor of ˜4.5 relative to a simple catalogue level matching and results in a ˜1.5 mag increase in the 80 per cent completeness limit of the NIR data. Almost 70 per cent of DES sources have useful NIR flux measurements in this initial catalogue. Photometric redshifts are estimated for a subset of galaxies with spectroscopic redshifts and initial results, although currently limited by small number statistics, indicate that the VHS data can help reduce the photometric redshift scatter at both z < 0.5 and z > 1. We present example DES+VHS colour selection criteria for high-redshift luminous red galaxies (LRGs) at z ˜ 0.7 as well as luminous quasars. Using spectroscopic observations in this field we show that the additional VHS fluxes enable a cleaner selection of both populations with <10 per cent contamination from galactic stars in the case of spectroscopically confirmed quasars and <0.5 per cent contamination from galactic stars in the case of spectroscopically confirmed LRGs. The combined DES+VHS data set, which will eventually cover almost 5000 sq-deg, will therefore enable a range of new science and be ideally suited for target selection for future wide-field spectroscopic surveys.

  19. Combining Dark Energy Survey Science Verification data with near-infrared data from the ESO VISTA Hemisphere Survey

    SciTech Connect

    Banerji, M.; Jouvel, S.; Lin, H.; McMahon, R. G.; Lahav, O.; Castander, F. J.; Abdalla, F. B.; Bertin, E.; Bosman, S. E.; Carnero, A.; Kind, M. C.; da Costa, L. N.; Gerdes, D.; Gschwend, J.; Lima, M.; Maia, M. A. G.; Merson, A.; Miller, C.; Ogando, R.; Pellegrini, P.; Reed, S.; Saglia, R.; Sanchez, C.; Allam, S.; Annis, J.; Bernstein, G.; Bernstein, J.; Bernstein, R.; Capozzi, D.; Childress, M.; Cunha, C. E.; Davis, T. M.; DePoy, D. L.; Desai, S.; Diehl, H. T.; Doel, P.; Findlay, J.; Finley, D. A.; Flaugher, B.; Frieman, J.; Gaztanaga, E.; Glazebrook, K.; Gonzalez-Fernandez, C.; Gonzalez-Solares, E.; Honscheid, K.; Irwin, M. J.; Jarvis, M. J.; Kim, A.; Koposov, S.; Kuehn, K.; Kupcu-Yoldas, A.; Lagattuta, D.; Lewis, J. R.; Lidman, C.; Makler, M.; Marriner, J.; Marshall, J. L.; Miquel, R.; Mohr, J. J.; Neilsen, E.; Peoples, J.; Sako, M.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sevilla, I.; Sharp, R.; Soares-Santos, M.; Swanson, M. E. C.; Tarle, G.; Thaler, J.; Tucker, D.; Uddin, S. A.; Wechsler, R.; Wester, W.; Yuan, F.; Zuntz, J.

    2014-11-25

    We present the combination of optical data from the Science Verification phase of the Dark Energy Survey (DES) with near-infrared (NIR) data from the European Southern Observatory VISTA Hemisphere Survey (VHS). The deep optical detections from DES are used to extract fluxes and associated errors from the shallower VHS data. Joint seven-band (grizYJK) photometric catalogues are produced in a single 3 sq-deg dedicated camera field centred at 02h26m-04d36m where the availability of ancillary multiwavelength photometry and spectroscopy allows us to test the data quality. Dual photometry increases the number of DES galaxies with measured VHS fluxes by a factor of similar to 4.5 relative to a simple catalogue level matching and results in a similar to 1.5 mag increase in the 80 per cent completeness limit of the NIR data. Almost 70 per cent of DES sources have useful NIR flux measurements in this initial catalogue. Photometric redshifts are estimated for a subset of galaxies with spectroscopic redshifts and initial results, although currently limited by small number statistics, indicate that the VHS data can help reduce the photometric redshift scatter at both z < 0.5 and z > 1. We present example DES VHS colour selection criteria for high-redshift luminous red galaxies (LRGs) at z similar to 0.7 as well as luminous quasars. Using spectroscopic observations in this field we show that the additional VHS fluxes enable a cleaner selection of both populations with <10 per cent contamination from galactic stars in the case of spectroscopically confirmed quasars and <0.5 per cent contamination from galactic stars in the case of spectroscopically confirmed LRGs. The combined DES+VHS data set, which will eventually cover almost 5000 sq-deg, will therefore enable a range of new science and be ideally suited for target selection for future wide-field spectroscopic surveys.

  20. SEARCHING FOR WATER EARTHS IN THE NEAR-INFRARED

    SciTech Connect

    Zugger, M. E.; Kane, T. J.; Kasting, J. F.; Williams, D. M.; Philbrick, C. R.

    2011-09-20

    Over 500 extrasolar planets (exoplanets) have now been discovered, but only a handful are small enough that they might be rocky terrestrial planets like Venus, Earth, and Mars. Recently, it has been proposed that observations of variability in scattered light (both polarized and total flux) from such terrestrial-sized exoplanets could be used to determine if they possess large surface oceans, an important indicator of potential habitability. Observing such oceans at visible wavelengths would be difficult, however, in part because of obscuration by atmospheric scattering. Here, we investigate whether observations performed in the near-infrared (NIR), where Rayleigh scattering is reduced, could improve the detectability of exoplanet oceans. We model two wavebands of the NIR which are 'window regions' for an Earth-like atmosphere: 1.55-1.75 {mu}m and 2.1-2.3 {mu}m. Our model confirms that obscuration in these bands from Rayleigh scattering is very low, but aerosols are generally the limiting factor throughout the wavelength range for Earth-like atmospheres. As a result, observations at NIR wavelengths are significantly better at detecting oceans than those at visible wavelengths only when aerosols are very thin by Earth standards. Clouds further dilute the ocean reflection signature. Hence, other techniques, e.g., time-resolved color photometry, may be more effective in the search for liquid water on exoplanet surfaces. Observing an exo-Earth at NIR wavelengths does open the possibility of detecting water vapor or other absorbers in the atmosphere, by comparing scattered light in window regions to that in absorption bands.

  1. NIFTE: The Near Infrared Faint-Object Telescope Experiment

    NASA Technical Reports Server (NTRS)

    Bock, James J.; Lange, Andrew E.; Matsumoto, T.; Eisenhardt, Peter B.; Hacking, Perry B.; Schember, Helene R.

    1994-01-01

    The high sensitivity of large format InSb arrays can be used to obtain deep images of the sky at 3-5 micrometers. In this spectral range cool or highly redshifted objects (e.g. brown dwarfs and protogalaxies) which are not visible at shorter wavelengths may be observed. Sensitivity at these wavelengths in ground-based observations is severly limited by the thermal flux from the telescope and from the earth's atmosphere. The Near Infrared Faint-Object Telescope Experiment (NIFTE), a 50 cm cooled rocket-borne telescope combined with large format, high performance InSb arrays, can reach a limiting flux less than 1 micro-Jy(1-sigma) over a large field-of-view in a single flight. In comparison, the Infrared Space Observatory (ISO) will require days of observation to reach a sensitivity more than one order of magnitude worse over a similar area of the sky. The deep 3-5 micrometer images obtained by the rocket-borne telescope will assist in determining the nature of faint red objects detected by ground-based telescopes at 2 micrometers, and by ISO at wavelengths longer than 5 micrometers.

  2. Optical and Near-infrared Study of Nova V2676 Oph 2012

    NASA Astrophysics Data System (ADS)

    Raj, A.; Das, R. K.; Walter, F. M.

    2017-02-01

    We present optical spectrophotometric and near-infrared (NIR) photometric observations of the nova V2676 Oph covering the period from 2012 March 29 through 2015 May 8. The optical spectra and photometry of the nova have been taken from SMARTS and Asiago; the NIR photometry was obtained from SMARTS and Mt. Abu. The spectra were dominated by strong H i lines from the Balmer series, Fe ii, N i, and [O i] lines in the initial days, typical of an Fe ii type nova. The measured FWHM for the Hβ and Hα lines was 800–1200 km s‑1. There was pronounced dust formation starting 90 days after the outburst. The J ‑ K color was the largest among recent dust-forming novae.

  3. NEAR-INFRARED THERMAL EMISSION FROM WASP-12b: DETECTIONS OF THE SECONDARY ECLIPSE IN Ks, H, AND J

    SciTech Connect

    Croll, Bryce; Jayawardhana, Ray; Lafreniere, David; Albert, Loic; Fortney, Jonathan J.; Murray, Norman

    2011-02-15

    We present Ks, H, and J-band photometry of the very highly irradiated hot Jupiter WASP-12b using the Wide-field Infrared Camera on the Canada-France-Hawaii telescope. Our photometry brackets the secondary eclipse of WASP-12b in the Ks and H bands, and in J band starts in mid-eclipse and continues until well after the end of the eclipse. We detect its thermal emission in all three near-infrared bands. Our secondary eclipse depths are 0.309{sup +0.013}{sub -0.012}% in Ks band (24{sigma}), 0.176{sup +0.016}{sub -0.021}% in H band (9{sigma}), and 0.131{sup +0.027}{sub -0.029}% in J band (4{sigma}). All three secondary eclipses are best fit with a consistent phase, {phi}, that is compatible with a circular orbit: {phi} = 0.4998{sup +0.0008}{sub -0.0007}. The limits on the eccentricity, e, and argument of periastron, {omega}, of this planet from our photometry alone are thus |ecos {omega}| < 0.0040. By combining our secondary eclipse times with others published in the literature, as well as the radial-velocity and transit-timing data for this system, we show that there is no evidence that WASP-12b is precessing at a detectable rate and that its orbital eccentricity is likely zero. Our thermal-emission measurements also allow us to constrain the characteristics of the planet's atmosphere; our Ks-band eclipse depth argues strongly in favor of inefficient day to nightside redistribution of heat and a low Bond albedo for this very highly irradiated hot Jupiter. The J- and H-band brightness temperatures are slightly cooler than the Ks-band brightness temperature, and thus hint at the possibility of a modest temperature inversion deep in the atmosphere of WASP-12b; the high-pressure, deep atmospheric layers probed by our J- and H-band observations are likely more homogenized than the higher altitude layer probed by our Ks-band observations. Lastly, our best-fit Ks-band eclipse has a marginally longer duration than would otherwise be expected; this may be tentative evidence for

  4. Study on near infrared technology for the measurement of moisture

    NASA Astrophysics Data System (ADS)

    Guo, Yong-cai; Chen, Zhao

    2006-02-01

    This paper studies near infrared technology for measuring moisture content in solid substance. After analyzing and improving traditional moisture instruments and discussing their disadvantages, we present a measuring scheme and instrument structure design with high performance and stability. The novel instrument utilizing near infrared range analysis (NIRA) technology possesses characteristics of on-line working, high accuracy, distribution and non-contact measurement.

  5. Near-infrared probes: design and applications

    NASA Astrophysics Data System (ADS)

    Patonay, G.; Strekowski, L.; Raszkiewicz, A.; Kim, J. S.

    2006-02-01

    Near-Infrared (NIR) absorbing chromophores have been valuable in analytical and bioanalytical chemistry. NIR probes and labels have been used for several applications, including solvent polarity, hydrophobicity, DNA sequencing, immunoassays, CE separations, etc. The NIR region (700-1100 nm) is more advantageous for the bioanalytical chemist due to the inherently lower background interference and the high molar absorptivities. NIR dyes can be used as simple probes to investigate biomolecule properties or just simply to detect the presence of biomolecules. Another typical application is the use of NIR fluorophores as labels. In these applications covalent labeling is the preferred method but it requires NIR dyes with appropriate reactive moieties. Due to the hydrophobic nature of NIR chromophores non-covalent labeling may be a viable alternative. For this purpose novel bis(carbocynines) have been developed in our laboratories. These dyes form intramolecular H-aggregates in polar solvents, even at very low concentrations. Spectral properties of this intramolecular dimer greatly depend on the properties of heterocyclic moieties and the length, the location and/or flexibility of the connecting chain. This form of the dye can be described as a clamshell complex with two interacting hydrophobic carbocyanine moieties. This intramolecular H-aggregate has a low extinction coefficient and fluorescence quantum yield. Upon opening the clamshell that can be facilitated by changing microhydrophobicity (i.e., binding to biomolecules) the H-and D- bands are decreased and the monomeric band is increased, with concomitant increase in fluorescence intensity. The main analytical utility of these bis(carbocyanines) is that the free dye (i.e., not complexed to an analyte) has negligible fluorescence in a typical aqueous buffer environment. Examples of different applications of these bis(carbocyanines) are given including forensic applications.

  6. Optical And Near-infrared Variability Among Distant Galactic Nuclei Of The CANDELS/Wide Fields

    NASA Astrophysics Data System (ADS)

    Grogin, Norman A.; Conselice, Christopher J.; Donley, Jennifer; Kartaltepe, Jeyhan; Kocevski, Dale; Koekemoer, Anton M.; Lucas, Ray; McGrath, Elizabeth; Rajan, Abhijit; Rosario, David; Salvato, Mara; Villforth, Carolin

    2015-08-01

    Three of the five fields surveyed during 2010-2013 by the CANDELS HST Multi-cycle Treasury Program were so-called "Wide" fields: CANDELS/UDS; CANDELS/COSMOS; and CANDELS/EGS. The area covered by CANDELS/Wide comprises WFC3/IR exposures in J-band and H-band across a total of 585 square arcminutes, and coordinated parallel ACS/WFC exposures in V-band and I-band across a total of 750 square arcminutes that largely overlaps the WFC3/IR coverage. In each field, these observations were split between two epochs with 52-day spacing for the primary purpose of high-redshift SNe detection and follow-up. However, the CANDELS combination of sensitivity, high resolution, and time spacing is also well-suited to detect optical and near-infrared variability ("ONIV") among moderate- to high-redshift galaxy nuclei (H<25AB mag; I<26AB mag).These data are sensitive to rest-frame variability time-scales of up to several weeks, and prior ACS/WFC imaging in CANDELS/COSMOS and CANDELS/EGS extends variability sensitivity to several years in the V- and I-bands. The overwhelming majority of these variable galaxy nuclei will be AGN; the small fraction arising from SNe have already been meticulously culled by the CANDELS high-redshift SNe search effort. These ONIV galaxy nuclei potentially represent a significant addition to the census of distant lower-luminosity AGN subject to multi-wavelength scrutiny with CANDELS.We present the combined results of our variability analyses, leading to the discovery of 133 I-band and 132 H-band ONIVs in CANDELS/Wide. We compare these HST-detected ONIVs with the known AGN candidates in the fields from deep Spitzer and Chandra imaging, and from extensive ground-based optical spectroscopy as well as HST IR-grism spectroscopy. We also assess the redshift distribution of the ONIVs from both spectroscopy and from robust SED-fitting incorporating ancillary deep ground-based imaging along with the CANDELS VIJH photometry. The I-band and H-band ONIVs are largely non

  7. WINGS: A WIde-field Nearby Galaxy-cluster Survey. II. Deep optical photometry of 77 nearby clusters

    NASA Astrophysics Data System (ADS)

    Varela, J.; D'Onofrio, M.; Marmo, C.; Fasano, G.; Bettoni, D.; Cava, A.; Couch, W. J.; Dressler, A.; Kjærgaard, P.; Moles, M.; Pignatelli, E.; Poggianti, B. M.; Valentinuzzi, T.

    2009-04-01

    Context: This is the second paper of a series devoted to the WIde Field Nearby Galaxy-cluster Survey (WINGS). WINGS is a long term project which is gathering wide-field, multi-band imaging and spectroscopy of galaxies in a complete sample of 77 X-ray selected, nearby clusters (0.04 < z < 0.07) located far from the galactic plane (|b|≥ 20°). The main goal of this project is to establish a local reference for evolutionary studies of galaxies and galaxy clusters. Aims: This paper presents the optical (B,V) photometric catalogs of the WINGS sample and describes the procedures followed to construct them. We have paid special care to correctly treat the large extended galaxies (which includes the brightest cluster galaxies) and the reduction of the influence of the bright halos of very bright stars. Methods: We have constructed photometric catalogs based on wide-field images in B and V bands using SExtractor. Photometry has been performed on images in which large galaxies and halos of bright stars were removed after modeling them with elliptical isophotes. Results: We publish deep optical photometric catalogs (90% complete at V ~ 21.7, which translates to ˜ M^*_V+6 at mean redshift), giving positions, geometrical parameters, and several total and aperture magnitudes for all the objects detected. For each field we have produced three catalogs containing galaxies, stars and objects of “unknown” classification (~6%). From simulations we found that the uncertainty of our photometry is quite dependent of the light profile of the objects with stars having the most robust photometry and de Vaucouleurs profiles showing higher uncertainties and also an additional bias of ~-0.2^m. The star/galaxy classification of the bright objects (V < 20) was checked visually making negligible the fraction of misclassified objects. For fainter objects, we found that simulations do not provide reliable estimates of the possible misclassification and therefore we have compared our data

  8. Near-infrared study of the stellar population of Sh2-152

    NASA Astrophysics Data System (ADS)

    Ramírez Alegría, S.; Herrero, A.; Marín-Franch, A.; Puga, E.; Najarro, F.; Acosta Pulido, J. A.; Hidalgo, S. L.; Simón-Díaz, S.

    2011-11-01

    Context. The discovery of new massive star clusters and massive stellar populations in previously known clusters in our Galaxy by means of infrared studies has changed our view of the Milky Way from an inactive to an active star-forming machine. Within this scenario, we present a near-infrared spectrophotometric study of the stellar content of the compact HII region Sh2-152. Aims: We aim to determine the distance, extinction, age, and mass of Sh2-152, using for the first time near-infrared stellar classification for several sources in the region. Methods: Using our near-infrared (J, H, and KS) photometry and the colour-magnitude diagram for the cluster field, we selected 13 bright stars, candidate members of the reddened cluster's main sequence, for H- and K-spectroscopy and spectral classification. This near-infrared information was complemented with an optical spectrum of the ionizing central star to confirm its spectral nature. Results: From the 13 spectroscopically observed stars, 5 were classified as B-type, 3 as G-type, 2 were young stellar objects (YSOs), and 3 remained unclassified (because of the poor data quality). The cluster's extinction varies from AKS = 0.5 to 2.6 mag (AV = 4.5 to 24 mag) and the distance is estimated to be 3.21 ± 0.21 kpc. The age of the cluster is younger than 9.4 Myr and the lower limit to the total mass of the cluster is (2.45 ± 0.79) × 103 M⊙. We compare the number of ionizing photons emitted from the OB-type stars with the Lyman continuum photons derived from the radio observations and conclude that both quantities are consistent for the central region of Sh2-152. In contrast, the main ionizing source of the lower region remains unidentified.

  9. A New Near-Infrared Spectral Atlas of O and Early-B Stars.

    NASA Astrophysics Data System (ADS)

    Hanson, M. M.; Kenworthy, M. A.; Puls, J.; Kudritzki, R.-P.; Tokunaga, A. T.

    2004-05-01

    We present new, high-resolution, near-infrared spectroscopy of three dozen O and early-B stars. The spectra cover most of the wavelength range between 1.62 μ m to 2.2 μ m and includes the most prominent lines of Hydrogen, Helium (both neutral and ionized) as well as three important metal lines in the H- and K-band region. These spectra have more than 4 times the resolution and 2-3 times the signal-to-noise of the the original O and B star spectral atlases of Hanson, Conti, and Rieke (1996) and Hanson, Rieke, and Luhman (1998). Our interest in obtaining higher resolution and signal-to-noise spectra was to aide in the development of quantitative spectroscopic analysis at near-infrared wavelengths which members in our group are carrying out. The new spectra obtained in this study are of high enough quality to allow for direct modeling of the line profiles to constrain effective temperature, gravity, rotational velocity and general wind characteristics. The development of atmospheric modeling routines for the near-infrared regime is fundamental to constraining the nature of heavily embedded and distant O and B stars presently being located throughout the disk of our Galaxy via deep near-infrared imaging surveys (2MASS, DENIS, MSX, GLIMPSE, etc). These results are based upon work supported by the National Science Foundation under Grant No. 0094050 to the University of Cincinnati.

  10. EDGES: Deep Multi-Wavelength Photometry and Radial SED Analysis for UGC8303 and UGC8320

    NASA Astrophysics Data System (ADS)

    Phenicie, Christopher; Dale, Daniel A.; Barnes, Kate L.; Beltz-Mohrmann, Gillian; Egan, Arika; Hatlestad, Alan; Herzog, Laura; Kobulnicky, Henry A.; Leung, Andrew S.; McLane, Jacob; Roberts, Jareth; Staudaher, Shawn; van Zee, Liese

    2015-01-01

    New deep ugr imaging was obtained on the Wyoming Infrared Observatory 2.3 meter telescope for UGC8303 and UGC8320, two galaxies in the Extended Disk Galaxy Exploration Science survey. These data are coupled with deep GALEX ultraviolet and Spitzer infrared imaging to study the radial variations in the spectral energy distributions. Results from the CIGALE SED modeling software will be presented, including trends in the galaxy star formation histories. This work is supported by the National Science Foundation under REU grant AST 1063146.

  11. EDGES: Deep Multi-Wavelength Photometry and Radial SED Analysis for Six Nearby Galaxies

    NASA Astrophysics Data System (ADS)

    Mclane, Jacob Noel; Leung, Andrew S.; Dale, Daniel A.; Barnes, Kate L.; Beltz-Mohrmann, Gillian; Egan, Arika; Hatlestad, Alan; Herzog, Laura; Kobulnicky, Henry A.; Phenicie, Christopher; Roberts, Jareth; Staudaher, Shawn; van Zee, Liese

    2015-01-01

    New deep ugr imaging was obtained on the Wyoming Infrared Observatory 2.3 meter telescope for NGC4220, NGC4618, NGC5055, NGC5523 and NGC5608, five galaxies in the Extended Disk Galaxy Exploration Science Survey (EDGES). Additional imaging was obtained for NGC4625, a non-EDGES target of opportunity. These data are coupled with deep GALEX ultraviolet and Spitzer/WISE infrared imaging to study the radial variations in the spectral energy distributions. Results from the CIGALE SED modeling software will be presented, including trends in the galaxy star formation histories. This work is supported by the National Science Foundation under REU grant AST 1063146.

  12. EDGES: Deep Multi-Wavelength Photometry and Radial SED Analysis for NGC4242 and UGC7301

    NASA Astrophysics Data System (ADS)

    Egan, Arika; Dale, Daniel A.; Barnes, Kate L.; Beltz-Mohrmann, Gillian; Hatlestad, Alan; Herzog, Laura; Kobulnicky, Henry A.; Leung, Andrew S.; McLane, Jacob; Phenicie, Christopher; Roberts, Jareth; Staudaher, Shawn; van Zee, Liese

    2015-01-01

    New deep ugr imaging was obtained on the Wyoming Infrared Observatory 2.3 meter telescope for NGC4242 and UGC7301, two galaxies in the Extended Disk Galaxy Exploration Science survey. These data are coupled with deep GALEX ultraviolet and Spitzer/WISE infrared imaging to study the radial variations in the spectral energy distributions. Results from the CIGALE SED modeling software will be presented, including trends in the galaxy star formation histories. This work is supported by the National Science Foundation under REU grant AST 1063146.

  13. EDGES: Deep Multi-Wavelength Photometry and Radial SED Analysis for NGC4707 and NGC5229

    NASA Astrophysics Data System (ADS)

    Herzog, Laura; Dale, Daniel A.; Barnes, Kate L.; Beltz-Mohrmann, Gillian; Egan, Arika; Hatlestad, Alan; Kobulnicky, Henry A.; Leung, Andrew S.; McLane, Jacob; Phenicie, Christopher; Roberts, Jareth; Staudaher, Shawn; van Zee, Liese

    2015-01-01

    New deep ugr imaging was obtained on the Wyoming Infrared Observatory 2.3 meter telescope for NGC4707 and NGC5229, two galaxies in the Extended Disk Galaxy Exploration Science survey. These data are coupled with deep GALEX ultraviolet and Spitzer infrared imaging to study the radial variations in the spectral energy distributions. Results from the CIGALE SED modeling software will be presented, including trends in the galaxy star formation histories. This work is supported by the National Science Foundation under REU grant AST 1063146.

  14. Deep Photometry of Galaxies in the VEGAS Survey: The Case of NGC 4472

    NASA Astrophysics Data System (ADS)

    Spavone, M.

    The VST-VEGAS project is aimed at observing and studying a rich sample of nearby early-type galaxies in order to systematically characterize their properties over a wide baseline of sizes and out to the faint outskirts where data are rather scarce so far. The external regions of galaxies more easily retain signatures about the formation and evolution mechanisms which shaped them, as their relaxation time are longer, and they are more weakly influenced by processes such as mergers, secular evolution, central black hole activity, and supernova feedback on the ISM, which tend to level age and metallicity gradients. The collection of a wide photometric dataset of a large number of galaxies in various environmental conditions, may help to shed light on these questions. To this end VEGAS exploits the potential of the VLT Survey Telescope (VST) which provides high quality images of 1 deg2 field of view in order to satisfy both the requirement of high resolution data and the need of studying nearby, and thus large, objects. We present a detailed study of the surface photometry of the elliptical galaxy NGC4472 and of smaller ETGs in its field, performed by using new g and i bands images to constrain the formation history of this nearby giant galaxy, and to investigate the presence of very faint substructures in its surroundings.

  15. [Drug release system controlled by near infrared light].

    PubMed

    Niidome, Takuro

    2013-01-01

    Gold nanorods have absorption bands in the near-infrared region; in this spectral range, light penetrates deeply into tissues. The absorbed light energy is converted into heat by gold nanorods. This is the so-called photothermal effect. Gold nanorods are therefore expected to act not only as thermal converters for photothermal therapy, but also as controllers for drug-release systems responding to irradiation with near-infrared light. To achieve a controlled-release system that could be triggered by light irradiation, the gold nanorods were modified with double-stranded DNA (dsDNA). When the dsDNA-modified gold nanorods were irradiated with near-infrared light, single-stranded DNA (ssDNA) was released from the gold nanorods because of the photothermal effect. The release of ssDNA was also observed in tumors grown on mice after near-infrared light irradiation. We also proposed a different controlled-release system responding to near-infrared light. Gold nanorods were modified with polyethylene glycol (PEG) through Diels-Alder cycloadducts. When the gold nanorods were irradiated with near-infrared light, the PEG chains were released from the gold nanorods because of the retro Diels-Alder reaction induced by the photothermal effect. Such controlled-release systems triggered by near-infrared light irradiation will be expanded for gold nanorod drug delivery system applications.

  16. Near-Infrared Photoluminescent Polymer-Carbon Nanodots with Two-Photon Fluorescence.

    PubMed

    Lu, Siyu; Sui, Laizhi; Liu, Junjun; Zhu, Shoujun; Chen, Anmin; Jin, Mingxing; Yang, Bai

    2017-02-13

    A facile, high-output strategy is developed for fabricating near-infrared-emissive polymer-carbon nanodots (PCNDs). The PCNDs emit at a wavelength of 710 nm with a QY of 26.28%, which is promising for deep biological imaging and luminescent devices. Moreover, the PCNDs possess two-photon fluorescence and. In vivo bioimaging and red light emitting diodes based on these PCNDs are demonstrated.

  17. Turbid Media Extinction Coefficient for Near-Infrared Laser Radiation

    NASA Astrophysics Data System (ADS)

    Dreischuh, T.; Gurdev, L.; Vankov, O.; Stoyanov, D.; Avramov, L.

    2015-03-01

    In this work, extended investigations are performed of the extinction coefficient of Intralipid-20% dilutions in distilled water depending on the Intralipid concentration, for laser radiation wavelengths in the red and near-infrared regions covering the so-called tissue optical window. The extinction is measured by using an approach we have developed recently based on the features of the spatial intensity distribution of laser-radiation beams propagating through semi-infinite turbid media. The measurements are conducted using separately two dilution- containing plexiglass boxes of different sizes and volumes, in order to prove the appropriateness of the assumption of semi-infinite turbid medium. The experimental results for the extinction are in agreement with our previous results and with empiric formulae found by other authors concerning the wavelength dependence of the scattering coefficient of Intralipid - 10% and Intralipid - 20%. They are also in agreement with known data of the water absorptance. It is estimated as well that the wavelengths around 1320 nm would be advantageous for deep harmless sensing and diagnostics of tissues.

  18. Sensitivity analysis of near-infrared functional lymphatic imaging

    PubMed Central

    Weiler, Michael; Kassis, Timothy

    2012-01-01

    Abstract. Near-infrared imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, yet the imaging capabilities of this approach have yet to be quantitatively characterized. We seek to quantify its capabilities as a diagnostic tool for lymphatic disease. Imaging is performed in a tissue phantom for sensitivity analysis and in hairless rats for in vivo testing. To demonstrate the efficacy of this imaging approach to quantifying immediate functional changes in lymphatics, we investigate the effects of a topically applied nitric oxide (NO) donor glyceryl trinitrate ointment. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being 150  μg/mL ICG and 60  g/L albumin. ICG fluorescence can be detected at a concentration of 150  μg/mL as deep as 6 mm with our system, but spatial resolution deteriorates below 3 mm, skewing measurements of vessel geometry. NO treatment slows lymphatic transport, which is reflected in increased transport time, reduced packet frequency, reduced packet velocity, and reduced effective contraction length. NIR imaging may be an alternative to invasive procedures measuring lymphatic function in vivo in real time. PMID:22734775

  19. Near-infrared (NIR) up-conversion optogenetics

    NASA Astrophysics Data System (ADS)

    Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Hoque, Mohammad Razuanul; Yamashita, Takayuki; Yamanaka, Akihiro; Sugano, Eriko; Tomita, Hiroshi; Yawo, Hiromu

    2015-11-01

    Non-invasive remote control technologies designed to manipulate neural functions have been long-awaited for the comprehensive and quantitative understanding of neuronal network in the brain as well as for the therapy of neurological disorders. Recently, it has become possible for the neuronal activity to be optically manipulated using biological photo-reactive molecules such as channelrhodopsin (ChR)-2. However, ChR2 and its relatives are mostly reactive to visible light, which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light (650-1450 nm) penetrates deep into the tissues because biological systems are almost transparent to light within this so-called ‘imaging window’. Here we used lanthanide nanoparticles (LNPs), composed of rare-earth elements, as luminous bodies to activate ChRs since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Here, we created a new type of optogenetic system which consists of the donor LNPs and the acceptor ChRs. The NIR laser irradiation emitted visible light from LNPs, then induced the photo-reactive responses in the near-by cells that expressed ChRs. However, there remains room for large improvements in the energy efficiency of the LNP-ChR system.

  20. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-06-01

    Near-infrared imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, yet the imaging capabilities of this approach have yet to be quantitatively characterized. We seek to quantify its capabilities as a diagnostic tool for lymphatic disease. Imaging is performed in a tissue phantom for sensitivity analysis and in hairless rats for in vivo testing. To demonstrate the efficacy of this imaging approach to quantifying immediate functional changes in lymphatics, we investigate the effects of a topically applied nitric oxide (NO) donor glyceryl trinitrate ointment. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being 150 μg/mL ICG and 60 g/L albumin. ICG fluorescence can be detected at a concentration of 150 μg/mL as deep as 6 mm with our system, but spatial resolution deteriorates below 3 mm, skewing measurements of vessel geometry. NO treatment slows lymphatic transport, which is reflected in increased transport time, reduced packet frequency, reduced packet velocity, and reduced effective contraction length. NIR imaging may be an alternative to invasive procedures measuring lymphatic function in vivo in real time.

  1. Near-infrared (NIR) up-conversion optogenetics

    PubMed Central

    Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Hoque, Mohammad Razuanul; Yamashita, Takayuki; Yamanaka, Akihiro; Sugano, Eriko; Tomita, Hiroshi; Yawo, Hiromu

    2015-01-01

    Non-invasive remote control technologies designed to manipulate neural functions have been long-awaited for the comprehensive and quantitative understanding of neuronal network in the brain as well as for the therapy of neurological disorders. Recently, it has become possible for the neuronal activity to be optically manipulated using biological photo-reactive molecules such as channelrhodopsin (ChR)-2. However, ChR2 and its relatives are mostly reactive to visible light, which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light (650–1450 nm) penetrates deep into the tissues because biological systems are almost transparent to light within this so-called ‘imaging window’. Here we used lanthanide nanoparticles (LNPs), composed of rare-earth elements, as luminous bodies to activate ChRs since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Here, we created a new type of optogenetic system which consists of the donor LNPs and the acceptor ChRs. The NIR laser irradiation emitted visible light from LNPs, then induced the photo-reactive responses in the near-by cells that expressed ChRs. However, there remains room for large improvements in the energy efficiency of the LNP-ChR system. PMID:26552717

  2. Advances in Organic Near-Infrared Materials and Emerging Applications.

    PubMed

    Qi, Ji; Qiao, Wenqiang; Wang, Zhi Yuan

    2016-06-01

    Much progress has been made in the field of research on organic near-infrared materials for potential applications in photonics, communications, energy, and biophotonics. This account mainly describes our research work on organic near-infrared materials; in particular, donor-acceptor small molecules, organometallics, and donor-acceptor polymers with the bandgaps less than 1.2 eV. The molecular designs, structure-property relationships, unique near-infrared absorption, emission and color/wavelength-changing properties, and some emerging applications are discussed.

  3. Deep Stromvil Photometry for Star Formation in the Head of the Pelican Nebula

    NASA Astrophysics Data System (ADS)

    Boyle, Richard P.; J., S.; Stott, J.; J., S.; Janusz, R.; J., S.; Straizys, V.

    2010-01-01

    The North America and Pelican Nebulae, and specifically the dark cloud L935 contain regions of active star formation (Herbig, G. H. 1958, ApJ, 128,259). Previously we reported on Vatican telescope observations by Stromvil intermediate-band filters in a 12-arcmin field in the "Gulf of Mexico" region of L935. There we classify A, F, and G-type stars. However, the many faint K and M-type dwarf stars remain somewhat ambiguous in calibration and classification. But attaining reasonable progress, we turn to another part of L935 located near the Pelican head. This area includes the "bright rim" which is formed by dust and gas condensed by the light pressure of an unseen O-type star hidden behind the dense dark cloud. Straizys and Laugalys (2008 Baltic Astronomy, 17, 143 ) have identified this star to be one of the 2MASS objects with Av=23 mag. A few concentrations of faint stars, V 13 to 14 mag. are immersed in this dark region. Among these stars are a few known emission-line objects (T-Tauri or post T-Tauri stars). A half degree nearby are some photometric Vilnius standards we use to calibrate our new field. We call on 2MASS data for correlative information. Also the Stromvil photometry offers candidate stars for spectral observations. The aim of this study in the Vilnius and Stromvil photometric systems is to classify stars down to V = 18 mag., to confirm the existence of the young star clusters, and to determine the distance of the cloud covering the suspected hidden ionizing star.

  4. Precise radial velocities in the near infrared

    NASA Astrophysics Data System (ADS)

    Redman, Stephen L.

    Since the first detection of a planet outside our Solar System byWolszczan & Frail (1992), over 500 exoplanets have been found to date2, none of which resemble the Earth. Most of these planets were discovered by measuring the radial velocity (hereafter, RV) of the host star, which wobbles under the gravitational influence of any existing planetary companions. However, this method has yet to achieve the sub-m/s precision necessary to detect an Earth-mass planet in the Habitable Zone (the region around a star that can support liquid water; hereafter, HZ) (Kasting et al. 1993) around a Solar-type star. Even though Kepler (Borucki et al. 2010) has announced several Earth-sized HZ candidates, these targets will be exceptionally difficult to confirm with current astrophysical spectrographs (Borucki et al. 2011). The fastest way to discover and confirm potentiallyhabitable Earth-mass planets is to observe stars with lower masses - in particular, late M dwarfs. While M dwarfs are readily abundant, comprising some 70% of the local stellar population, their low optical luminosity presents a formidable challenge to current optical RV instruments. By observing in the near-infrared (hereafter, NIR), where the flux from M dwarfs peaks, we can potentially reach low RV precisions with significantly less telescope time than would be required by a comparable optical instrument. However, NIR precision RV measurements are a relatively new idea and replete with challenges: IR arrays, unlike CCDs, are sensitive to the thermal background; modal noise is a bigger issue in the NIR than in the optical; and the NIR currently lacks the calibration sources like the very successful thorium-argon (hereafter, ThAr) hollow-cathode lamp and Iodine gas cell of the optical. The PSU Pathfinder (hereafter, Pathfinder) was designed to explore these technical issues with the intention of mitigating these problems for future NIR high-resolution spectrographs, such as the Habitable-Zone Planet Finder (HZPF

  5. Deep Space 1 photometry of the nucleus of Comet P/19 Borrelly

    NASA Technical Reports Server (NTRS)

    Buratti, B. J.; Britt, D.; Oberst, J.; Soderblom, L. A.; Hillier, J. K.; Hicks, M. D.

    2002-01-01

    The NASA-JPL Deep Space 1 Mission (DS1) encountered the short-period Jupiter-family comet 19/P Borrelly on September 22, 2001, about 8 days after perihelion. DS1's payload contained a remote-sensing package that included a 1024 square CCD and a near IR spectrometer with 12nm resolution. Prior to its closest approach, the remote-sensing package on the spacecraft obtained 25 CCD images of the comet and 45 near-IR spectra.

  6. Near infrared imaging of Uranus and Neptune

    SciTech Connect

    Smith, B.A.

    1984-10-01

    Imaging of Uranus and Neptune in the deep methane absorption band at 890nm is used to detect high altitude atmospheric hazes and to search for possible undiscovered close in satellites. The appearances of Uranus and Neptune are very different from one another and Uranus seems to be changing with time. The Neptune images show rotation in the direct sense.

  7. Tissue blood flow and oxygen consumption measured with near-infrared frequency-domain spectroscopy

    NASA Astrophysics Data System (ADS)

    Paunescu, Lelia Adelina

    2001-12-01

    For decades, researchers have contributed with new ways of applying physics' principles to medicine. Moreover, researchers were involved in developing new, non-invasive instrumentation for medical applications. Recently, application of optical techniques in biology and medicine became an important field. Researchers found a non- invasive approach of using visible and near-infrared light as a probe for tissue investigation. Optical methods can contribute to medicine by offering the possibility of rapid, low-resolution, functional images and real-time devices. Near-infrared spectroscopy (NIRS) is a useful technique for the investigation of biological tissues because of the relatively low absorption of water and high absorption of oxy- and deoxy-hemoglobin in the near- infrared region of 750-900 nm. Due to these properties, the near-infrared light can penetrate biological tissues in the range of 0.5-2 cm, offering investigation possibility of deep tissues and differentiate among healthy and diseased tissues. This work represents the initial steps towards understanding and improving of the promising near- infrared frequency-domain technique. This instrument has a very important advantage: it can be used non-invasively to investigate many parts of the human body, including the brain. My research consists primarily of in vivo measurements of optical parameters such as absorption and reduced scattering coefficients and consequently, blood parameters such as oxy, deoxy, and total hemoglobin concentrations, tissue oxygen saturation, blood flow and oxygen consumption of skeletal muscle of healthy and diseased subjects. This research gives a solid background towards a ready- to-use instrument that can continuously, in real-time, measure blood parameters and especially blood oxygenation. This is a very important information in emergency medicine, for persons under intensive care, or undergoing surgery, organ transplant or other interventions.

  8. Near-infrared (NIR) optogenetics using up-conversion system

    NASA Astrophysics Data System (ADS)

    Hososhima, Shoko; Yuasa, Hideya; Ishizuka, Toru; Yawo, Hiromu

    2015-03-01

    Non-invasive remote control technologies designed to manipulate neural functions for a comprehensive and quantitative understanding of the neuronal network in the brain as well as for the therapy of neurological disorders have long been awaited. Recently, it has become possible to optically manipulate the neuronal activity using biological photo-reactive molecules such as channelrhodopsin-2 (ChR2). However, ChR2 and its relatives are mostly reactive to visible light which does not effectively penetrate through biological tissues. In contrast, near-infrared (NIR) light penetrates deep into the tissues because biological systems are almost transparent to light within this so-called `imaging window'. Here we used lanthanide nanoparticles (LNPs), which are composed of rare-earth elements, as luminous bodies to activate channelrhodopsins (ChRs) since they absorb low-energy NIR light to emit high-energy visible light (up-conversion). Neuron-glioma-hybrid ND-7/23 cells were cultured with LNP(NaYF4:Sc/Yb/Er) particles (peak emission, 543 nm) and transfected to express C1V1 (peak absorbance, 539 nm), a chimera of ChR1 and VChR1. The photocurrents were generated in response to NIR laser light (976 nm) to a level comparable to that evoked by a filtered Hg lamp (530-550 nm). NIR light pulses also evoked action potentials in the cultured neurons that expressed C1V1. It is suggested that the green luminescent light emitted from LNPs effectively activated C1V1 to generate the photocurrent. With the optimization of LNPs, acceptor photo-reactive biomolecules and optics, this system could be applied to non-invasively actuate neurons deep in the brain.

  9. Sensitivity analysis of near-infrared functional lymphatic imaging

    NASA Astrophysics Data System (ADS)

    Weiler, Michael; Kassis, Timothy; Dixon, J. Brandon

    2012-03-01

    Background - Near-infrared (NIR) imaging of lymphatic drainage of injected indocyanine green (ICG) has emerged as a new technology for clinical imaging of lymphatic architecture and quantification of vessel function, offering better spatial and temporal resolution than competing imaging modalities. While NIR lymphatic imaging has begun to be reported in the literature, the technology is still in its infancy and its imaging capabilities have yet to be quantitatively characterized. The objective of this study, therefore, was to characterize the parameters of NIR lymphatic imaging to quantify its capabilities as a diagnostic tool for evaluating lymphatic disease. Methods - An NIR imaging system was developed using a laser diode for excitation, ICG as a fluorescent agent, and a CCD camera to detect emission. A tissue phantom with mock lymphatic vessels of known depths and diameters was used as an alternative to in vivo lymphatic vessels due to the greater degree of control with the phantom. Results and Conclusions - When dissolved in an albumin physiological salt solution (APSS) to mimic interstitial fluid, ICG experiences shifts in the excitation/emission wavelengths such that it is maximally excited at 805nm and produces peak fluorescence at 840nm. Premixing ICG with albumin induces greater fluorescence intensity, with the ideal concentration being: 900μM (60g/L) albumin and 193.5μM (150μg/mL) ICG. ICG fluorescence can be detected as deep as 6mm, but spatial resolution deteriorates severely below 3mm, thus skewing vessel geometry measurements. ICG packet travel, a common measure of lymphatic transport, can be detected as deep as 5mm.

  10. The optical and near-infrared colors of galaxies, 1: The photometric data

    NASA Technical Reports Server (NTRS)

    Bershady, Matthew A.; Hereld, Mark; Kron, Richard G.; Koo, David C.; Munn, Jeffrey A.; Majewski, Steven R.

    1994-01-01

    We present optical and near-infrared photometry and spectroscopic redshifts of a well defined sample of 171 field galaxies selected from three high galactic latitude fields. This data set forms the basis for subsequent studies to characterize the trends, dispersion, and evolution of rest-frame colors and image structure. A subset of 143 galaxies constitutes a magnitude-limited sample to B approx. 19.9-20.75 (depending on field), with a median redshift of 0.14, and a maximum redshift of 0.54. This subset is statistically representative in its sampling of the apparent color distribution of galaxies. Thirty six galaxies were selected to have the reddest red-optical colors in two redshift intervals between 0.2 less than z less than 0.3. Photometric passbands are similar to U, B, V, I, and K, and sample galaxy spectral energy distributions between 0.37 and 2.2 micrometers in the observed frame, or down to 0.26 micrometers in the rest frame for the most distant galaxies. B and K images of the entire sample are assembled to form the first optical and near-infrared atlas of a statistically-representative sample of field galaxies. We discuss techniques for faint field-galaxy photometry, including a working definition of a total magnitude, and a method for matching magnitudes in different passbands and different seeing conditions to ensure reliable, integrated colors. Photographic saturation, which substantially affects the brightest 12% of our sample in the optical bands, is corrected with a model employing measured plate-density distributions for each galaxy, calibrated via similar measurements for stars as a function of known saturation level. Both the relative and absolute calibration of our photometry are demonstrated.

  11. Applications Of Microspectroscopy In The Near-Infrared Region

    NASA Astrophysics Data System (ADS)

    Smith, Matthew J.; Carl, Richard T.

    1989-12-01

    The technique of infrared microspectroscopy has numerous applications in many fields including materials science, forensics, contamination analysis and biological science. The majority of these applications have been in the mid-infrared since using different spectral ranges in an FT-IR spectrometer often involve modifications to the interferometer, source and detector. However, recent advancements in infrared instrumentation have allowed rapid spectral range changes to become routine. As a result, near-infrared microspectroscopy is now a viable technique.1 The principle advantage of near-infrared microspectroscopy is the ability to analyze samples which are totally absorbing in the mid-infrared region. Most near-infrared absorbances are due to overtones or combination bands of fundamental bands and are typically one to two orders of magnitude weaker than their corresponding fundamental transitions. Thus, transmission analysis in the near-infrared can be carried out on many samples which are otherwise too thick for transmission analysis in the mid-infrared.

  12. Near-infrared branding efficiently correlates light and electron microscopy.

    PubMed

    Bishop, Derron; Nikić, Ivana; Brinkoetter, Mary; Knecht, Sharmon; Potz, Stephanie; Kerschensteiner, Martin; Misgeld, Thomas

    2011-06-05

    The correlation of light and electron microscopy of complex tissues remains a major challenge. Here we report near-infrared branding (NIRB), which facilitates such correlation by using a pulsed, near-infrared laser to create defined fiducial marks in three dimensions in fixed tissue. As these marks are fluorescent and can be photo-oxidized to generate electron contrast, they can guide re-identification of previously imaged structures as small as dendritic spines by electron microscopy.

  13. Nano-plasmonic antennas in the near infrared regime.

    PubMed

    Berkovitch, N; Ginzburg, P; Orenstein, M

    2012-02-22

    Plasmonic nano-antennas constitute a central research topic in current science and engineering with an enormous variety of potential applications. Here we review the recent progress in the niche of plasmonic nano-antennas operating in the near infrared part of the spectrum which is important for a variety of applications. Tuning of the resonance into the near infrared regime is emphasized in the perspectives of fabrication, measurement, modeling, and analytical treatments, concentrating on the vast recent achievements in these areas.

  14. NEAR-INFRARED PHOTOMETRIC PROPERTIES OF 130,000 QUASARS: AN SDSS-UKIDSS-MATCHED CATALOG

    SciTech Connect

    Peth, Michael A.; Ross, Nicholas P.; Schneider, Donald P.

    2011-04-15

    We present a catalog of over 130,000 quasar candidates with near-infrared (NIR) photometric properties, with an areal coverage of approximately 1200 deg{sup 2}. This is achieved by matching the Sloan Digital Sky Survey (SDSS) in the optical ugriz bands to the UKIRT Infrared Digital Sky Survey (UKIDSS) Large Area Survey (LAS) in the NIR YJHK bands. We match the {approx}1 million SDSS DR6 Photometric Quasar catalog to Data Release 3 of the UKIDSS LAS (ULAS) and produce a catalog with 130,827 objects with detections in one or more NIR bands, of which 74,351 objects have optical and K-band detections and 42,133 objects have the full nine-band photometry. The majority ({approx}85%) of the SDSS objects were not matched simply because these were not covered by the ULAS. The positional standard deviation of the SDSS Quasar to ULAS matches is {delta}{sub R.A.} = 0.''1370 and {delta}{sub decl.} = 0.''1314. We find an absolute systematic astrometric offset between the SDSS Quasar catalog and the UKIDSS LAS, of |R.A.{sub offset}| = 0.''025 and |decl.{sub offset}| = 0.''040; we suggest the nature of this offset to be due to the matching of catalog, rather than image, level data. Our matched catalog has a surface density of {approx}53 deg{sup -2} for K {<=} 18.27 objects; tests using our matched catalog, along with data from the UKIDSS Deep Extragalactic Survey, imply that our limiting magnitude is i {approx} 20.6. Color-redshift diagrams, for the optical and NIR, show a close agreement between our matched catalog and recent quasar color models at redshift z {approx}< 2.0, while at higher redshifts, the models generally appear to be bluer than the mean observed quasar colors. The gJK and giK color spaces are used to examine methods of differentiating between stars and (mid-redshift) quasars, the key to currently ongoing quasar surveys. Finally, we report on the NIR photometric properties of high, z > 4.6, and very high, z > 5.7, redshift previously discovered quasars.

  15. Near-infrared Photometric Properties of 130,000 Quasars: An SDSS-UKIDSS-matched Catalog

    NASA Astrophysics Data System (ADS)

    Peth, Michael A.; Ross, Nicholas P.; Schneider, Donald P.

    2011-04-01

    We present a catalog of over 130,000 quasar candidates with near-infrared (NIR) photometric properties, with an areal coverage of approximately 1200 deg2. This is achieved by matching the Sloan Digital Sky Survey (SDSS) in the optical ugriz bands to the UKIRT Infrared Digital Sky Survey (UKIDSS) Large Area Survey (LAS) in the NIR YJHK bands. We match the ≈1 million SDSS DR6 Photometric Quasar catalog to Data Release 3 of the UKIDSS LAS (ULAS) and produce a catalog with 130,827 objects with detections in one or more NIR bands, of which 74,351 objects have optical and K-band detections and 42,133 objects have the full nine-band photometry. The majority (~85%) of the SDSS objects were not matched simply because these were not covered by the ULAS. The positional standard deviation of the SDSS Quasar to ULAS matches is δR.A. = 0farcs1370 and δdecl. = 0farcs1314. We find an absolute systematic astrometric offset between the SDSS Quasar catalog and the UKIDSS LAS, of |R.A.offset| = 0farcs025 and |decl.offset| = 0farcs040; we suggest the nature of this offset to be due to the matching of catalog, rather than image, level data. Our matched catalog has a surface density of ≈53 deg-2 for K <= 18.27 objects; tests using our matched catalog, along with data from the UKIDSS Deep Extragalactic Survey, imply that our limiting magnitude is i ≈ 20.6. Color-redshift diagrams, for the optical and NIR, show a close agreement between our matched catalog and recent quasar color models at redshift z <~ 2.0, while at higher redshifts, the models generally appear to be bluer than the mean observed quasar colors. The gJK and giK color spaces are used to examine methods of differentiating between stars and (mid-redshift) quasars, the key to currently ongoing quasar surveys. Finally, we report on the NIR photometric properties of high, z > 4.6, and very high, z > 5.7, redshift previously discovered quasars.

  16. Deep HST/ACS Photometry of an Arc of Young Stars in the Southern Halo of M82

    NASA Astrophysics Data System (ADS)

    Suwannajak, Chutipong

    2016-01-01

    We present deep HST/ACS photometry of an arclike, overdense region of stars in the southern halo of M82, located approximately 5 kpc from its disk. This arc feature was originally identified about a decade ago. The early ground-based studies suggested that it contains young stars with ages and metallicities similar to those that formed in the tidal tails between M81, M82, and NGC3077 during their interactions. The arc is clearly presented in the spatial distribution of stars in our field with significantly higher stellar density than the background M82 halo stars. The location of the tip of the red giant branch (RGB) reveals the arc to have a similar distance to M81 and M82, therefore confirming that it belongs to this interacting system. Combining our data with those from the ACS Nearby Galaxy Survey Treasury (ANGST), we construct a color-magnitude diagram (CMD) for the arc. A sequence of young stars is clearly presented on its CMD. This young main sequence is not seen in other parts of the M82 halo. Single-metallicity isochrones are used to derive the age of the young stars in the arc. We confirm that these stars exhibit ages consistent with young stars found in the HI bridges between M81, M82 and NGC3077. Furthermore, the mean metallicity of the RGB stars is also derived from their metallicity distribution function and found to be similar to that found in the HI bridges.

  17. AKARI OBSERVATION OF THE SUB-DEGREE SCALE FLUCTUATION OF THE NEAR-INFRARED BACKGROUND

    SciTech Connect

    Seo, H. J.; Lee, Hyung Mok; Lee, Myung Gyoon; Matsumoto, T.; Jeong, W.-S.; Pyo, J.

    2015-07-10

    We report spatial fluctuation analysis of the sky brightness in the near-infrared from observations toward the north ecliptic pole (NEP) by the AKARI at 2.4 and 3.2 μm. As a follow-up study of our previous work on the Monitor field of AKARI, we used NEP deep survey data, which covered a circular area of about 0.4 square degrees, in order to extend fluctuation analysis at angular scales up to 1000″. We found residual fluctuation over the estimated shot noise at larger angles than the angular scale of the Monitor field. The excess fluctuation of the NEP deep field smoothly connects with that of the Monitor field at angular scales of a few hundred arcseconds and extends without any significant variation to larger angular scales up to 1000″. By comparing excess fluctuations at two wavelengths, we confirm a blue spectral feature similar to the result of the Monitor field. We find that the result of this study is consistent with Spitzer Space Telescope observations at 3.6 μm. The origin of the excess fluctuation in the near-infrared background remains to be determined, but we could exclude zodiacal light, diffuse Galactic light, and unresolved faint galaxies at low redshift based on the comparison with mid- and far-infrared brightness, ground-based near-infrared images.

  18. A route to brightly fluorescent carbon nanotubes for near-infrared imaging in mice

    PubMed Central

    Welsher, Kevin; Liu, Zhuang; Sherlock, Sarah P.; Robinson, Joshua Tucker; Chen, Zhuo; Daranciang, Dan; Dai, Hongjie

    2010-01-01

    The near-infrared photoluminescence intrinsic to semiconducting single-walled carbon nanotubes is ideal for biological imaging owing to the low autofluorescence and deep tissue penetration in the near-infrared region beyond 1 µm. However, biocompatible single-walled carbon nanotubes with high quantum yield have been elusive. Here, we show that sonicating single-walled carbon nanotubes with sodium cholate, followed by surfactant exchange to form phospholipid–polyethylene glycol coated nanotubes, produces in vivo imaging agents that are both bright and biocompatible. The exchange procedure is better than directly sonicating the tubes with the phospholipid–polyethylene glycol, because it results in less damage to the nanotubes and improves the quantum yield. We show whole-animal in vivo imaging using an InGaAs camera in the 1–1.7 µm spectral range by detecting the intrinsic near-infrared photoluminescence of the ‘exchange’ single-walled carbon nanotubes at a low dose (17 mg l−1 injected dose). The deep tissue penetration and low autofluorescence background allowed high-resolution intravital microscopy imaging of tumour vessels beneath thick skin. PMID:19893526

  19. Deep HST Photometry of NGC 6388: Age and Horizontal Branch Luminosity

    NASA Technical Reports Server (NTRS)

    Stetson, Peter B.; Catelan, M.; Pritzl, Barton J.; Smith, Horace A.; Kinemuchi, Karen; Layden, Andrew C.; Sweigart, Allen V.; Rich, R. M.

    2006-01-01

    We present the first deep color-magnitude diagram (CMD) of the Galactic globular cluster NGC 6388, obtained with the Hubble Space Telescope, that is able to reach the main-sequence turnoff point of the cluster. From a detailed comparison between the cluster CMD and that of 47 Tucanae (NGC 104), we find that the bulk of the stars in these two clusters have nearly the same age and chemical composition. On the other hand, our results indicate that the blue horizontal branch and RR Lyrae components in NGC 6388 are intrinsically over-luminous, which must be due to one or more, still undetermined, non-canonical second parameter(s) affecting a relatively minor fraction of the stars in NGC 6388.

  20. NEAR-INFRARED VARIABILITY IN YOUNG STARS IN CYGNUS OB7

    SciTech Connect

    Rice, Thomas S.; Wolk, Scott J.; Aspin, Colin

    2012-08-10

    We present the first results from a 124 night J, H, K near-infrared monitoring campaign of the dark cloud L 1003 in Cygnus OB7, an active star-forming region. Using three seasons of UKIRT observations spanning 1.5 years, we obtained high-quality photometry on 9200 stars down to J = 17 mag, with photometric uncertainty better than 0.04 mag. On the basis of near-infrared excesses from disks, we identify 30 pre-main-sequence stars, including 24 which are newly discovered. We analyze those stars and find that the NIR excesses are significantly variable. All 9200 stars were monitored for photometric variability; among the field star population, {approx}160 exhibited near-infrared variability (1.7% of the sample). Of the 30 young stellar objects (YSOs), 28 of them (93%) are variable at a significant level. Of the 30 YSOs, twenty-five have near-infrared excess consistent with simple disk-plus-star classical T Tauri models. Nine of these (36%) drift in color space over the course of these observations and/or since Two Micron All Sky Survey observations such that they cross the boundary defining the NIR excess criteria; effectively, they have a transient near-infrared excess. Thus, time-series JHK observations can be used to obtain a more complete sample of disk-bearing stars than single-epoch JHK observations. About half of the YSOs have color-space variations parallel to either the classical T Tauri star locus or a hybrid track which includes the dust reddening trajectory. This indicates that the NIR variability in YSOs that possess accretion disks arises from a combination of variable extinction and changes in the inner accretion disk: either in accretion rate, central hole size, and/or the inclination of the inner disk. While some variability may be due to stellar rotation, the level of variability on the individual stars can exceed a magnitude. This is a strong empirical suggestion that protoplanetary disks are quite dynamic and exhibit more complex activity on short

  1. Efficient near-infrared up-conversion photoluminescence in carbon nanotubes

    PubMed Central

    Akizuki, Naoto; Aota, Shun; Mouri, Shinichiro; Matsuda, Kazunari; Miyauchi, Yuhei

    2015-01-01

    Photoluminescence phenomena normally obey Stokes' law of luminescence according to which the emitted photon energy is typically lower than its excitation counterparts. Here we show that carbon nanotubes break this rule under one-photon excitation conditions. We found that the carbon nanotubes exhibit efficient near-infrared photoluminescence upon photoexcitation even at an energy lying >100–200 meV below that of the emission at room temperature. This apparently anomalous phenomenon is attributed to efficient one-phonon-assisted up-conversion processes resulting from unique excited-state dynamics emerging in an individual carbon nanotube with accidentally or intentionally embedded localized states. These findings may open new doors for energy harvesting, optoelectronics and deep-tissue photoluminescence imaging in the near-infrared optical range. PMID:26568250

  2. New and Better Near-Infrared Detectors for JWST Near Infrared Spectrograph

    NASA Technical Reports Server (NTRS)

    Rauscher, Bernard J.; Mott, D. Brent; Wen, Yiting; Linder, Don; Greenhouse, Matthew A.; Hill, Robert J.

    2014-01-01

    ESA and NASA recently selected two 5 m cutoff Teledyne H2RG sensor chip assemblies (SCA) for flight on the James Webb Space Telescope (JWST) Near Infrared Spectrograph (NIRSpec). These HgCdTe SCAs incorporate Teledynes improved barrier layer design that eliminates the degradation that affected earlier JWST H2RGs(Rauscher et al. 2012a). The better indium barrier, together with other design changes, has improved the performance and reliability of JWSTs SCAs. In this article, we describe the measured performance characteristics that most directly affect scientific observations including read noise, total noise, dark current, quantum efficiency (QE), and image persistence. As part of measuring QE, we measured the quantum yield as a function of photon energy,, and found that it exceeds unity for photon energies E (2.65.2) Eg, where Eg is the HgCdTe bandgap energy. This corresponds to. 2 m for NIRSpecs 5 m cutoff HgCdTe. Our measurements agree well with a previous measurement by McCullough et al. (2008) for. 1.3. For 1.3, we find a slower increase in with photon energy than McCullough et al. did. However, and as McCullough et al. note, their two state model of the yield process is not valid for large 1.

  3. An optical and near-infrared study of the Type Ia/IIn Supernova PS15si

    NASA Astrophysics Data System (ADS)

    Kilpatrick, Charles D.; Andrews, Jennifer E.; Smith, Nathan; Milne, Peter; Rieke, George H.; Zheng, WeiKang; Filippenko, Alexei V.

    2016-11-01

    We present optical/near-infrared spectroscopy and photometry of the supernova (SN) PS15si. This object was originally identified as a Type IIn SN, but here we argue that it should be reclassified as a Type Ia SN with narrow hydrogen lines originating from interaction with circumstellar matter (CSM; i.e. SN Ia/IIn or SN Ia-CSM). Based on deep non-detections 27 d before discovery, we infer that this SN was discovered around or slightly before optical maximum, and we estimate the approximate time that it reached R-band maximum based on comparison with other SNe Ia/IIn. In terms of spectral morphology, we find that PS15si can be matched to a range of SN Ia spectral types, although SN 1991T-like SNe Ia provides the most self-consistent match. While this spectral classification agrees with analysis of most other SNe Ia/IIn, we find that the implied CSM-interaction luminosity is too low. We infer that the similarity between PS15si and the hot, overluminous, high-ionization spectrum of SN 1991T is a consequence of a spectrum that originates in ejecta layers that are heated by ultraviolet/X-ray radiation from CSM interaction. In addition, PS15si may have rebrightened over a short time-scale in the B and V bands around 85 d after discovery, perhaps indicating that the SN ejecta are interacting with a local enhancement in CSM produced by clumps or a shell at large radii.

  4. Using Near Infrared Observations and Models to Analyze Surface Compositions of Kuiper Belt Objects

    NASA Astrophysics Data System (ADS)

    McGuire, Ryan

    Kuiper Belt Objects (KBOs) are primordial icy objects in the outer solar system. Compositional information for KBOs helps us understand the original environment of the solar system as well as identify objects that are compositionally anomalous. Due to the faint nature of KBOs, very few spectroscopic observations have been made of them. Instead, photometric observations at infrared wavelengths are made to partially construct their spectra. I calculate near infrared reflectances for 12 objects using photometric observations from the Gemini North telescope. I combine these near infrared reflectances with data from the Spitzer Space Telescope. This combination of Gemini and Spitzer photometry along with compositional model analysis allows us to find the surface composition (organics, H2O, CO2, CH4, and other hydrated silicates) for these 12 objects. I found that my objects fit into one of four taxonomic classes found in the Kuiper Belt. We have found using the color analysis, that Haumea has water on its surface and Eris is most likely to have methane on its surface. By analyzing this data we measure the compositional mixing in the outer solar system.

  5. Near-Infrared, Kilosecond Variability of the Wisps And Jet in the Crab Pulsar Wind Nebula

    SciTech Connect

    Melatos, Andrew; Scheltus, D.; Whiting, M.T.; Eikenberry, S.S.; Romani, R.W.; Rigaut, F.; Spitkovsky, A.; Arons, J.; Payne, D.J.B.; /Melbourne U.

    2006-01-11

    We present a time-lapse sequence of 20 near-infrared (J- and K'-band) snapshots of the central 20'' x 20'' of the Crab pulsar wind nebula, taken at sub-arcsecond resolution with the Hokupa'a/QUIRC adaptive optics camera on the Gemini North Telescope, and sampled at intervals of 10 minutes and 24 hours. It is observed that the equatorial wisps and polar knots in the termination shock of the pulsar wind appear to fluctuate in brightness on kilosecond time-scales. Maximum flux variations of {+-}24 {+-} 4 and {+-}14 {+-} 4 per cent relative to the mean (in 1.2 ks) are measured for the wisps and knots respectively, with greatest statistical significance in J band where the nebula background is less prominent. The J and K' flux densities imply different near-infrared spectra for the nonthermal continuum emission from the wisps and outermost polar knot (''sprite''), giving F{sub {nu}} {proportional_to} {nu}{sup -0.56{+-}0.12} and F{sub {nu}} {proportional_to} {nu}{sup -0.21{+-}0.13} respectively. The data are compared with existing optical and UV photometry and applied to constrain theories of the variability of the wisps (relativistic ion-cyclotron instability) and knots (relativistic fire hose instability).

  6. Rapid response near-infrared spectrophotometric characterization of Near Earth Objects

    NASA Astrophysics Data System (ADS)

    Mommert, Michael; Trilling, David; Axelrod, Tim; Butler, Nat; Jedicke, Robert; Moskovitz, Nicholas; Pichardo, Barbara; Reyes, Mauricio

    2014-11-01

    Small NEOs are, as a whole, poorly characterized, and we know nothing about the physical properties of the majority of all NEOs. The rate of NEO discoveries is increasing each year, and projects to determine the physical properties of NEOs are lagging behind. NEOs are faint, and generally even fainter by the time that follow-up characterizations can be made days or weeks later. There is a need for a high-throughput, high-efficiency physical characterization strategy in which hundreds of faint NEOs can be characterized each year. Broadband photometry in the near-infrared is sufficiently diagnostic to assign taxonomic types, and hence constrain both the individual and ensemble properties of NEOs. We will present results from our recently initiated program of rapid response near-infrared spectrophotometric characterization of NEOs. We are using UKIRT (on Mauna Kea) and the RATIR instrument on the 1.5m telescope at the San Pedro Martir Observatory (Mexico) to allow us to make observations most nights of the year in robotic/queue mode. This technique is powerful and fast. We have written automated software that allows us to observe NEOs very soon after discovery. Our targets are NEOs that are generally too faint for other characterization techniques. We are on pace to characterize hundreds of NEOs per year.

  7. A near-infrared survey of old novae. I - The discovery of a candidate recurrent nova

    NASA Astrophysics Data System (ADS)

    Harrison, Thomas E.

    1992-12-01

    We report on a near-infrared survey of old novae in an attempt to discover previously unidentified members of the RS Oph family of recurrent novae. An RS Oph-type system contains a red giant, and is easily identified using infrared photometry. Two objects in our survey have infrared colors and luminosities that suggest that they may be recurrent novae: V723 Sco and AR Cir. We use a model of the Galaxy to rule out the possibility of source confusion in either case. The light curve of the 1952 outburst of V723 Sco was very similar to those of the other members of the RS Oph group of recurrent novae, and we conclude that it is a previously unidentified member of this family. The light curve of the 1906 outburst of AR Cir, however, more closely resembles those of the outbursts of symbiotic stars, and we classify it as such.

  8. Near infrared spectroscopy of stearic acid adsorbed on montmorillonite.

    PubMed

    Lu, Longfei; Cai, Jingong; Frost, Ray L

    2010-03-01

    The adsorption of stearic acid on both sodium montmorillonites and calcium montmorillonites has been studied by near infrared spectroscopy complimented with infrared spectroscopy. Upon adsorption of stearic acid on Ca-Mt additional near infrared bands are observed at 8236 cm(-1) and is assigned to an interaction of stearic acid with the water of hydration. Upon adsorption of the stearic acid on Na-Mt, the NIR bands are now observed at 5671, 5778, 5848 and 5912 cm(-1) and are assigned to the overtone and combination bands of the CH fundamentals. Additional bands at 4177, 4250, 4324, 4337, 4689 and 4809 cm(-1) are attributed to CH combination bands resulting from the adsorption of the stearic acid. Stearic acid is used as a model molecule for adsorption studies. The application of near infrared spectroscopy to the study of this adsorption proved most useful.

  9. [Study on near-infrared absorption mechanism of alkali lignin].

    PubMed

    Wu, Xin-sheng; Xie, Yi-min; Liu, Huan-bin; Wu, Hong

    2006-06-01

    The results showed that o-quinone and q-quinone had strong absorption while vanillin had nearly no absorption in the 800-900 nm range of near-infrared spectroscopy through the comparison of their near-infrared absorption spectra. It was proved that quinone structure of alkali lignin had strong absorption in the 800-900 nm range of near-infrared spectroscopy. The change in the absorbency of oleander milled wood lignin treated with NaOH and Na2 S before and after is greater than that in the absorbency of ginkgo milled wood lignin treated with NaOH and Na2 S before and after because more quinone structure was formed in the process of oleander milled wood lignin treated with NaOH and Na2 S. The finding well explained that cooking liquor of hardwood was much stronger than that of softwood while their pulp kappa number was very near.

  10. Near infrared reflectance analysis by Gauss-Jordan linear algebra

    NASA Astrophysics Data System (ADS)

    Honigs, D. E.; Freelin, J. M.; Hieftje, G. M.

    1983-02-01

    Near-infrared reflectance analysis (NIRA) is an analytical technique that uses the near-infrared diffuse reflectance of a sample at several discrete wavelengths to predict the concentration of one or more of the chemical species in that sample. However, because near-infrared bands from solid samples are both abundant and broad, the reflectance at a given wavelength usually contains contributions from several sample components, requiring extensive calculations on overlapped bands. In the present study, these calculations have been performed using an approach similar to that employed in multi-component spectrophotometry, but with Gauss-Jordan linear algebra serving as the computational vehicle. Using this approach, correlations for percent protein in wheat flour and percent benzene in hydrocarbons have been obtained and are evaluated. The advantages of a linear-algebra approach over the common one employing stepwise regression are explored.

  11. In vivo near-infrared dual-axis confocal microendoscopy in the human lower gastrointestinal tract

    NASA Astrophysics Data System (ADS)

    Piyawattanametha, Wibool; Ra, Hyejun; Qiu, Zhen; Friedland, Shai; Liu, Jonathan T. C.; Loewke, Kevin; Kino, Gordon S.; Solgaard, Olav; Wang, Thomas D.; Mandella, Michael J.; Contag, Christopher H.

    2012-02-01

    Near-infrared confocal microendoscopy is a promising technique for deep in vivo imaging of tissues and can generate high-resolution cross-sectional images at the micron-scale. We demonstrate the use of a dual-axis confocal (DAC) near-infrared fluorescence microendoscope with a 5.5-mm outer diameter for obtaining clinical images of human colorectal mucosa. High-speed two-dimensional en face scanning was achieved through a microelectromechanical systems (MEMS) scanner while a micromotor was used for adjusting the axial focus. In vivo images of human patients are collected at 5 frames/sec with a field of view of 362×212 μm2 and a maximum imaging depth of 140 μm. During routine endoscopy, indocyanine green (ICG) was topically applied a nonspecific optical contrasting agent to regions of the human colon. The DAC microendoscope was then used to obtain microanatomic images of the mucosa by detecting near-infrared fluorescence from ICG. These results suggest that DAC microendoscopy may have utility for visualizing the anatomical and, perhaps, functional changes associated with colorectal pathology for the early detection of colorectal cancer.

  12. Breast phantom for mammary tissue characterization by near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Miranda, D. A.; Cristiano, K. L.; Gutiérrez, J. C.

    2013-11-01

    Breast cancer is a disease associated to a high morbidity and mortality in the entire world. In the study of early detection of breast cancer the development of phantom is so important. In this research we fabricate a breast phantom using a ballistic gel with special modifications to simulate a normal and abnormal human breast. Optical properties of woman breast in the near infrared region were modelled with the phantom we developed. The developed phantom was evaluated with near infrared spectroscopy in order to study its relation with breast tissue. A good optical behaviour was achieved with the model fabricated.

  13. Detecting Counterfeit Antimalarial Tablets by Near-Infrared Spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Counterfeit antimalarial drugs are found in many developing countries, but it is challenging to differentiate between genuine and fakes due to their increasing sophistication. Near-infrared spectroscopy (NIRS) is a powerful tool in pharmaceutical forensics, and we tested this technique for discrim...

  14. Comparative hazard evaluation of near-infrared diode lasers.

    PubMed

    Marshall, W J

    1994-05-01

    Hazard evaluation methods from various laser protection standards differ when applied to extended-source, near-infrared lasers. By way of example, various hazard analyses are applied to laser training systems, which incorporate diode lasers, specifically those that assist in training military or law enforcement personnel in the proper use of weapons by simulating actual firing by the substitution of a beam of near-infrared energy for bullets. A correct hazard evaluation of these lasers is necessary since simulators are designed to be directed toward personnel during normal use. The differences among laser standards are most apparent when determining the hazard class of a laser. Hazard classification is based on a comparison of the potential exposures with the maximum permissible exposures in the 1986 and 1993 versions of the American National Standard for the Safe Use of Lasers, Z136.1, and the accessible emission limits of the federal laser product performance standard. Necessary safety design features of a particular system depend on the hazard class. The ANSI Z136.1-1993 standard provides a simpler and more accurate hazard assessment of low-power, near-infrared, diode laser systems than the 1986 ANSI standard. Although a specific system is evaluated, the techniques described can be readily applied to other near-infrared lasers or laser training systems.

  15. Social Perception in Infancy: A Near Infrared Spectroscopy Study

    ERIC Educational Resources Information Center

    Lloyd-Fox, Sarah; Blasi, Anna; Volein, Agnes; Everdell, Nick; Elwell, Claire E.; Johnson, Mark H.

    2009-01-01

    The capacity to engage and communicate in a social world is one of the defining characteristics of the human species. While the network of regions that compose the social brain have been the subject of extensive research in adults, there are limited techniques available for monitoring young infants. This study used near infrared spectroscopy to…

  16. Cotton micronaire measurements by small portable near infrared (nir) analyzers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A key quality and processing parameter for cotton fiber is micronaire, which is a function of the fiber’s maturity and fineness. Near Infrared (NIR) spectroscopy has previously shown the ability to measure micronaire, primarily in the laboratory and using large, research-grade laboratory NIR instru...

  17. Near-infrared spectroscopic tissue imaging for medical applications

    DOEpatents

    Demos, Stavros; Staggs, Michael C.

    2006-12-12

    Near infrared imaging using elastic light scattering and tissue autofluorescence are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

  18. Near-infrared spectroscopic tissue imaging for medical applications

    DOEpatents

    Demos; Stavros , Staggs; Michael C.

    2006-03-21

    Near infrared imaging using elastic light scattering and tissue autofluorescence are explored for medical applications. The approach involves imaging using cross-polarized elastic light scattering and tissue autofluorescence in the Near Infra-Red (NIR) coupled with image processing and inter-image operations to differentiate human tissue components.

  19. Enhancement of near-infrared absorption in graphene with metal gratings

    SciTech Connect

    Zhao, B.; Zhang, Z. M.; Zhao, J. M.

    2014-07-21

    Graphene has been demonstrated as a good candidate for ultrafast optoelectronic devices. However, graphene is essentially transparent in the visible and near infrared with an absorptivity of 2.3%, which has largely limited its application in photon detection. This Letter demonstrates that the absorptance in a monatomic graphene layer can be greatly enhanced to nearly 70%, thanks to the localized strong electric field resulting from magnetic resonances in deep metal gratings. Furthermore, the resonance frequency is essentially not affected by the additional graphene layer. The method presented here may benefit the design of next-generation graphene-based optical and optoelectronic devices.

  20. In Vivo Fluorescence Imaging in the Second Near-Infrared Window Using Carbon Nanotubes.

    PubMed

    Hong, Guosong; Dai, Hongjie

    2016-01-01

    In vivo fluorescence imaging in the second near-infrared window (NIR-II window, 1000-1700 nm) is a powerful imaging technique that emerged in recent years. This imaging tool allows for noninvasive, deep-tissue visualization and interrogation of anatomical features and functions with improved imaging resolution and contrast at greater tissue penetration depths than traditional fluorescence imaging. Here, we present the detailed protocol for conducting NIR-II fluorescence imaging in live animals, including the procedures for preparation of biocompatible and NIR-II fluorescent carbon nanotube solution, live animal administration and NIR-II fluorescence image acquisition.

  1. The void galaxy survey: photometry, structure and identity of void galaxies

    NASA Astrophysics Data System (ADS)

    Beygu, B.; Peletier, R. F.; Hulst, J. M. van der; Jarrett, T. H.; Kreckel, K.; Weygaert, R. van de; van Gorkom, J. H.; Aragon-Calvo, M. A.

    2017-01-01

    We analyse photometry from deep B-band images of 59 void galaxies in the Void Galaxy Survey (VGS), together with their near-infrared 3.6 μm and 4.5 μm Spitzer photometry. The VGS galaxies constitute a sample of void galaxies that were selected by a geometric-topological procedure from the Sloan Digital Sky Survey Data Release 7 data release, and which populate the deep interior of voids. Our void galaxies span a range of absolute B-magnitude from MB = -15.5 to -20, while at the 3.6 μm band their magnitudes range from M3.6 = -18 to -24. Their B-[3.6] colour and structural parameters indicate these are star-forming galaxies. A good reflection of the old stellar population, the near-infrared band photometry also provide a robust estimate of the stellar mass, which for the VGS galaxies we confirm to be smaller than 3 × 1010 M⊙. In terms of the structural parameters and morphology, our findings align with other studies in that our VGS galaxy sample consists mostly of small late-type galaxies. Most of them are similar to Sd-Sm galaxies, although a few are irregularly shaped galaxies. The sample even includes two early-type galaxies, one of which is an AGN. Their Sérsic indices are nearly all smaller than n = 2 in both bands and they also have small half-light radii. In all, we conclude that the principal impact of the void environment on the galaxies populating them mostly concerns their low stellar mass and small size.

  2. Three-Color, Narrow-Band, Near-Infrared Photometry of Mira Stars

    NASA Astrophysics Data System (ADS)

    Rebel, B.; Henson, G.

    1996-12-01

    The calibration of a photometric system used to detect spectral type changes of M-type stars is described. The system consists of three filters used to measure an index of TiO band strength, a color index, and an infrared continuum magnitude as described by Wing (1992, J.AAVSO, 21, 47). A plot of TiO index versus spectral type shows the system to be sensitive to spectral changes of approximately 1/2 subtype over the range of M1 to M7. The system will be used to provide coarse spectral information to supplement the infrared and visual light curves of M-type variables. We have established absolute magnitudes in all three filters for a set of 10 standard stars and have begun synoptic observations of Mira variable stars. Light curves with corresponding spectral type and color changes will be presented for six Mira stars: Z Oph, T Her, W Lyr, RT Cyg, CN Cyg, and R Vul.

  3. Near-Infrared Quantum Cutting Long Persistent Luminescence

    NASA Astrophysics Data System (ADS)

    Zou, Zehua; Feng, Lin; Cao, Cheng; Zhang, Jiachi; Wang, Yuhua

    2016-05-01

    By combining the unique features of the quantum cutting luminescence and long persistent luminescence, we design a new concept called “near-infrared quantum cutting long persistent luminescence (NQPL)”, which makes it possible for us to obtain highly efficient (>100%) near-infrared long persistent luminescence in theory. Guided by the NQPL concept, we fabricate the first NQPL phosphor Ca2Ga2GeO7:Pr3+,Yb3+. It reveals that both the two-step energy transfer of model (I) and the one-step energy transfer of model (IV) occur in 3P0 levels of Pr3+. Although the actual efficiency is not sufficient for the practical application at this primitive stage, this discovery and the associated materials are still expected to have important implications for several fields such as crystalline Si solar cells and bio-medical imaging.

  4. Near-Infrared Quantum Cutting Long Persistent Luminescence

    PubMed Central

    Zou, Zehua; Feng, Lin; Cao, Cheng; Zhang, Jiachi; Wang, Yuhua

    2016-01-01

    By combining the unique features of the quantum cutting luminescence and long persistent luminescence, we design a new concept called “near-infrared quantum cutting long persistent luminescence (NQPL)”, which makes it possible for us to obtain highly efficient (>100%) near-infrared long persistent luminescence in theory. Guided by the NQPL concept, we fabricate the first NQPL phosphor Ca2Ga2GeO7:Pr3+,Yb3+. It reveals that both the two-step energy transfer of model (I) and the one-step energy transfer of model (IV) occur in 3P0 levels of Pr3+. Although the actual efficiency is not sufficient for the practical application at this primitive stage, this discovery and the associated materials are still expected to have important implications for several fields such as crystalline Si solar cells and bio-medical imaging. PMID:27143282

  5. Near-infrared uncaging or photosensitizing dictated by oxygen tension

    NASA Astrophysics Data System (ADS)

    Anderson, Erin D.; Gorka, Alexander P.; Schnermann, Martin J.

    2016-11-01

    Existing strategies that use tissue-penetrant near-infrared light for the targeted treatment of cancer typically rely on the local generation of reactive oxygen species. This approach can be impeded by hypoxia, which frequently occurs in tumour microenvironments. Here we demonstrate that axially unsymmetrical silicon phthalocyanines uncage small molecules preferentially in a low-oxygen environment, while efficiently generating reactive oxygen species in normoxic conditions. Mechanistic studies of the uncaging reaction implicate a photoredox pathway involving photoinduced electron transfer to generate a key radical anion intermediate. Cellular studies demonstrate that the biological mechanism of action is O2-dependent, with reactive oxygen species-mediated phototoxicity in normoxic conditions and small molecule uncaging in hypoxia. These studies provide a near-infrared light-targeted treatment strategy with the potential to address the complex tumour landscape through two distinct mechanisms that vary in response to the local O2 environment.

  6. Near-infrared Mueller matrix imaging for colonic cancer detection

    NASA Astrophysics Data System (ADS)

    Wang, Jianfeng; Zheng, Wei; Lin, Kan; Huang, Zhiwei

    2016-03-01

    Mueller matrix imaging along with polar decomposition method was employed for the colonic cancer detection by polarized light in the near-infrared spectral range (700-1100 nm). A high-speed (<5s) Muller matrix imaging system with dual-rotating waveplates was developed. 16 (4 by 4) full Mueller matrices of the colonic tissues (i.e., normal and caner) were acquired. Polar decomposition was further implemented on the 16 images to derive the diattentuation, depolarization, and the retardance images. The decomposed images showed clear margin between the normal and cancerous colon tissue samples. The work shows the potential of near-infrared Mueller matrix imaging for the early diagnosis and detection of malignant lesions in the colon.

  7. Image-guided cancer surgery using near-infrared fluorescence

    PubMed Central

    Vahrmeijer, Alexander L.; Hutteman, Merlijn; van der Vorst, Joost R.; van de Velde, C.J.H.; Frangioni, John V.

    2013-01-01

    Paradigm shifts in surgery arise when surgeons are empowered to perform surgery faster, better, and/or less expensively. Optical imaging that exploits invisible near-infrared fluorescent light has the potential to improve cancer surgery outcomes while minimizing anesthesia time and lowering healthcare costs. Because of this, the last few years have witnessed an explosion of proof-of-concept clinical trials in the field. In this review, we introduce the concept of near-infrared fluorescence imaging for cancer surgery, review the clinical trial literature to date, outline the key issues pertaining to imaging system and contrast agent optimization, discuss limitations and leverage, and provide a framework for making the technology available for the routine care of cancer patients in the near future. PMID:23881033

  8. [Progress in noninvasive biochemical examination by near infrared spectroscopy].

    PubMed

    Ding, Hai-quan; Lu, Qi-peng; Peng, Zhong-qi; Chen, Xing-dan

    2010-08-01

    In the early nineties of last century, great importance had been gradually attached to the potential of near-infrared spectroscopy (NIRS) in the human body noninvasive biochemical examination. However, the human body is extremely complex. Although research teams have made some achievements in experimental simulations and in-vitro analysis, there is still no substantive breakthrough in clinical application now. The present paper discusses the key problems which prevent NIRS from achieving human noninvasive clinical biochemical examination, such as weak signal, the interference of human tissue background and the problem of blood volume change. The thoughts of noninvasive biomedical examination using NIRS are divided into two categories in terms of analytical method, that is classical near-infrared analysis and issue background interference elimination analysis. This paper also introduces in detail the current status of the two categories in the world, and believes that the second category is more promising to be successful in clinical application under the existing conditions.

  9. Near-infrared photodetector with reduced dark current

    DOEpatents

    Klem, John F; Kim, Jin K

    2012-10-30

    A photodetector is disclosed for the detection of near-infrared light with a wavelength in the range of about 0.9-1.7 microns. The photodetector, which can be formed as either an nBp device or a pBn device on an InP substrate, includes an InGaAs light-absorbing layer, an InAlGaAs graded layer, an InAlAs or InP barrier layer, and an InGaAs contact layer. The photodetector can detect near-infrared light with or without the use of an applied reverse-bias voltage and is useful as an individual photodetector, or to form a focal plane array.

  10. [Near infrared spectroscopy study on water content in turbine oil].

    PubMed

    Chen, Bin; Liu, Ge; Zhang, Xian-Ming

    2013-11-01

    Near infrared (NIR) spectroscopy combined with successive projections algorithm (SPA) was investigated for determination of water content in turbine oil. Through the 57 samples of different water content in turbine oil scanned applying near infrared (NIR) spectroscopy, with the water content in the turbine oil of 0-0.156%, different pretreatment methods such as the original spectra, first derivative spectra and differential polynomial least squares fitting algorithm Savitzky-Golay (SG), and successive projections algorithm (SPA) were applied for the extraction of effective wavelengths, the correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices, accordingly water content in turbine oil was investigated. The results indicated that the original spectra with different water content in turbine oil were pretreated by the performance of first derivative + SG pretreatments, then the selected effective wavelengths were used as the inputs of least square support vector machine (LS-SVM). A total of 16 variables selected by SPA were employed to construct the model of SPA and least square support vector machine (SPA-LS-SVM). There is 9 as The correlation coefficient was 0.975 9 and the root of mean square error of validation set was 2.655 8 x 10(-3) using the model, and it is feasible to determine the water content in oil using near infrared spectroscopy and SPA-LS-SVM, and an excellent prediction precision was obtained. This study supplied a new and alternative approach to the further application of near infrared spectroscopy in on-line monitoring of contamination such as water content in oil.

  11. Discovery in translation: near-infrared fluorescence imaging

    NASA Astrophysics Data System (ADS)

    Sevick-Muraca, Eva M.

    2012-01-01

    When translating new imaging modalities into the clinic, one can expect new discoveries. Owing to the high photon count rates, near-infrared fluorescence (NIRF) offers exquisite sensitivity and high temporal resolution that enable new insights into human disorders. Herein, the physics of NIRF are highlighted and compared to those involved in nuclear medicine techniques. The initial application of investigational NIRF involving characterization of the lymphatics in humans and animal models of human disease yields discoveries not otherwise attainable with conventional imaging.

  12. Near-infrared sensitive organic-inorganic photorefractive device

    NASA Astrophysics Data System (ADS)

    Marinova, Vera; Liu, Ren-Chung; Lin, Shiuan-Huei; Chen, Ming-Syuan; Lin, Yi-Hsin; Hsu, Ken-Yuh

    2016-10-01

    Organic-inorganic hybrid structure, assembled by Rh-doped Bi12TiO20 crystal and liquid crystal (LC) layer, operating at near-infrared range is proposed and demonstrated. Due to the photorefractive properties of inorganic substrate, light illumination caused a space charge field which acts as a driving force for LC molecules re-alignment and subsequent refractive index modulation. All optically controlled phase retardation ability has been demonstrated supporting possibilities for further infrared applications.

  13. Near-infrared emission from mesoporous crystalline germanium

    SciTech Connect

    Boucherif, Abderraouf; Aimez, Vincent; Arès, Richard; Korinek, Andreas

    2014-10-15

    Mesoporous crystalline germanium was fabricated by bipolar electrochemical etching of Ge wafer in HF-based electrolyte. It yields uniform mesoporous germanium layers composed of high density of crystallites with an average size 5-7 nm. Subsequent extended chemical etching allows tuning of crystallites size while preserving the same chemical composition. This highly controllable nanostructure exhibits photoluminescence emission above the bulk Ge bandgap, in the near-infrared range (1095-1360nm) with strong evidence of quantum confinement within the crystallites.

  14. Near-Infrared Reflectance of Snow-Covered Substrates,

    DTIC Science & Technology

    1981-11-01

    I - NEAR-INFRA RED RFETANCE OF SNOW-COVERED SUBSTRATES.IU) INoV SL H B RIEN, . KOH UNCLASSIF IED CRREL-8-21N L ~~LEVE REPORT 81-21 Near-infrared...that more than half of the radiant The condition of the snow cover at the time energy transmitted by the so-called 1.3-,um filter may explain the shape

  15. Near-infrared fundus autoflorescence imaging in solar retinopathy

    PubMed Central

    Czepita, Maciej; Machalińska, Anna; Czepita, Damian

    2017-01-01

    Solar retinopathy is a rare clinical entity caused by photochemical damage to the retinal pigment epithelium layer and photoreceptors of the fovea. Here we describe a case of a 33-year-old female patient diagnosed by near-infrared fundus autofluorescence imaging for signs of damage to the melanosomes of the retinal pigment epithelium of the fovea. The patient was advised to discontinue looking at the sun with the naked eye. PMID:28293534

  16. Near-Infrared Fluorescent Nanoprobes for in Vivo Optical Imaging

    PubMed Central

    Quek, Chai-Hoon; Leong, Kam W.

    2012-01-01

    Near-infrared (NIR) fluorescent probes offer advantages of high photon penetration, reduced light scattering and minimal autofluorescence from living tissues, rendering them valuable for noninvasive mapping of molecular events, assessment of therapeutic efficacy, and monitoring of disease progression in animal models. This review provides an overview of the recent development of the design and optical property of the different classes of NIR fluorescent nanoprobes associated with in vivo imaging applications.

  17. Tunable Near-Infrared Luminescence in Tin Halide Perovskite Devices.

    PubMed

    Lai, May L; Tay, Timothy Y S; Sadhanala, Aditya; Dutton, Siân E; Li, Guangru; Friend, Richard H; Tan, Zhi-Kuang

    2016-07-21

    Infrared emitters are reasonably rare in solution-processed materials. Recently, research into hybrid organo-lead halide perovskite, originally popular in photovoltaics,1-3 has gained traction in light-emitting diodes (LED) due to their low-cost solution processing and good performance.4-9 The lead-based electroluminescent materials show strong colorful emission in the visible region, but lack emissive variants further in the infrared. The concerns with the toxicity of lead may, additionally, limit their wide-scale applications. Here, we demonstrate tunable near-infrared electroluminescence from a lead-free organo-tin halide perovskite, using an ITO/PEDOT:PSS/CH3NH3Sn(Br1-xIx)3/F8/Ca/Ag device architecture. In our tin iodide (CH3NH3SnI3) LEDs, we achieved a 945 nm near-infrared emission with a radiance of 3.4 W sr(-1) m(-2) and a maximum external quantum efficiency of 0.72%, comparable with earlier lead-based devices. Increasing the bromide content in these tin perovskite devices widens the semiconductor bandgap and leads to shorter wavelength emissions, tunable down to 667 nm. These near-infrared LEDs could find useful applications in a range of optical communication, sensing and medical device applications.

  18. IR CMOS: near infrared enhanced digital imaging (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Pralle, Martin U.; Carey, James E.; Joy, Thomas; Vineis, Chris J.; Palsule, Chintamani

    2015-08-01

    SiOnyx has demonstrated imaging at light levels below 1 mLux (moonless starlight) at video frame rates with a 720P CMOS image sensor in a compact, low latency camera. Low light imaging is enabled by the combination of enhanced quantum efficiency in the near infrared together with state of the art low noise image sensor design. The quantum efficiency enhancements are achieved by applying Black Silicon, SiOnyx's proprietary ultrafast laser semiconductor processing technology. In the near infrared, silicon's native indirect bandgap results in low absorption coefficients and long absorption lengths. The Black Silicon nanostructured layer fundamentally disrupts this paradigm by enhancing the absorption of light within a thin pixel layer making 5 microns of silicon equivalent to over 300 microns of standard silicon. This results in a demonstrate 10 fold improvements in near infrared sensitivity over incumbent imaging technology while maintaining complete compatibility with standard CMOS image sensor process flows. Applications include surveillance, nightvision, and 1064nm laser see spot. Imaging performance metrics will be discussed. Demonstrated performance characteristics: Pixel size : 5.6 and 10 um Array size: 720P/1.3Mpix Frame rate: 60 Hz Read noise: 2 ele/pixel Spectral sensitivity: 400 to 1200 nm (with 10x QE at 1064nm) Daytime imaging: color (Bayer pattern) Nighttime imaging: moonless starlight conditions 1064nm laser imaging: daytime imaging out to 2Km

  19. A near-infrared SETI experiment: instrument overview

    NASA Astrophysics Data System (ADS)

    Wright, Shelley A.; Werthimer, Dan; Treffers, Richard R.; Maire, Jérôme; Marcy, Geoffrey W.; Stone, Remington P. S.; Drake, Frank; Meyer, Elliot; Dorval, Patrick; Siemion, Andrew

    2014-07-01

    We are designing and constructing a new SETI (Search for Extraterrestrial Intelligence) instrument to search for direct evidence of interstellar communications via pulsed laser signals at near-infrared wavelengths. The new instrument design builds upon our past optical SETI experiences, and is the first step toward a new, more versatile and sophisticated generation of very fast optical and near-infrared pulse search devices. We present our instrumental design by giving an overview of the opto-mechanical design, detector selection and characterization, signal processing, and integration procedure. This project makes use of near-infrared (950 - 1650 nm) discrete amplification Avalanche Photodiodes (APD) that have > 1 GHz bandwidths with low noise characteristics and moderate gain (~104). We have investigated the use of single versus multiple detectors in our instrument (see Maire et al., this conference), and have optimized the system to have both high sensitivity and low false coincidence rates. Our design is optimized for use behind a 1m telescope and includes an optical camera for acquisition and guiding. A goal is to make our instrument relatively economical and easy to duplicate. We describe our observational setup and our initial search strategies for SETI targets, and for potential interesting compact astrophysical objects.

  20. Near-infrared IFU and MOS observations of supernova remnants

    NASA Astrophysics Data System (ADS)

    Lee, Ho-Gyu

    2016-06-01

    We present near-infrared IFU and MOS observations of two bright [Fe II] line emitting supernova remnants (SNRs). The two SNRs, G11.2-0.3 and RCW103, are selected from our near-infrared [Fe II] 1.64 um narrow band imaging survey of SNRs such as UKIRT unbiased [Fe II] imaging survey of the the Galactic plane and AAT [Fe II] imaging of some core-collapse SNRs. We detect several near-infrared hyperfine lines of [Fe II] at the southeastern shell of G11.2-0.3. We estimate the line strength and extinction-corrected density, which gives a clue to the origin of the iron-rich southeastern shell of G11.2-0.3. We obtain the MOS spectra of [Fe II]-emitting clumps inside RCW103. The observed clumps move about hundreds kilometers in radial direction, suggesting that they are shocked dense materials lost by stellar wind at the final stage of the evolution of the progenitor star.

  1. Near-infrared image filtering for pedestrian surveillance

    NASA Astrophysics Data System (ADS)

    Rodhouse, Kathryn N.; Watkins, Steve E.

    2012-04-01

    An image processing approach is investigated which has low computational complexity and which uses nearinfrared imaging. The target application is a surveillance system for pedestrian traffic. Near-infrared light has potential benefits including non-visible illumination requirements. An image-processing algorithm for monitoring pedestrians is implemented in outdoor and indoor environments with frequent traffic. The image sets consist of persons walking in the presence of foreground as well as background objects at different times during the day. The complex, cluttered environments are highly variable, e.g. shadows and moving foliage. The approach consists of thresholding an image and creating a silhouette of selected objects in the scene. Filtering is used to eliminate noise. The computational results using MATLABshow that the algorithm can effectively manipulate near-infrared images and that effective filtering is possible even in the presence of system noise and environmental clutter. The potential for automated surveillance based on near-infrared imaging and neural-network based feature processing is discussed.

  2. NIP: the near infrared imaging photometer for Euclid

    NASA Astrophysics Data System (ADS)

    Schweitzer, Mario; Bender, Ralf; Katterloher, Reinhard; Eisenhauer, Frank; Hofmann, Reiner; Saglia, Roberto; Holmes, Rory; Krause, Oliver; Rix, Hans-Walter; Booth, Jeff; Fagrelius, Parker; Rhodes, Jason; Seshadri, Suresh; Refregier, Alexandre; Amiaux, Jerome; Augueres, Jean-Louis; Boulade, Olivier; Cara, Christophe; Amara, Adam; Lilly, Simon; Atad-Ettedgui, Eli; di Giorgio, Anna-Maria; Duvet, Ludovic; Kuehl, Christopher; Syed, Mohsin

    2010-07-01

    The NIP is a near infrared imaging photometer that is currently under investigation for the Euclid space mission in context of ESA's 2015 Cosmic Vision program. Together with the visible camera (VIS) it will form the basis of the weak lensing measurements for Euclid. The NIP channel will perform photometric imaging in 3 near infrared bands (Y, J, H) covering a wavelength range from ~ 0.9 to 2 μm over a field of view (FoV) of ~ 0.5 deg2. With the required limiting point source magnitude of 24 mAB (5 sigma) the NIP channel will be used to determine the photometric redshifts of over 2 billion galaxies collected over a wide survey area of 20 000 deg2. In addition to the photometric measurements, the NIP channel will deliver unique near infrared (NIR) imaging data over the entire extragalactic sky, enabling a wide variety of ancillary astrophysical and cosmological studies. In this paper we will present the results of the study carried out by the Euclid Imaging Consortium (EIC) during the Euclid assessment phase.

  3. Near-infrared camera for the Clementine mission

    SciTech Connect

    Priest, R.E.; Lewis, I.T.; Sewall, N.R.; Park, H.S.; Shannon, M.J.; Ledebuhr, A.G.; Pleasance, L.D.; Massie, M.A.; Metschuleit, K.

    1995-04-01

    The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultra-violet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. The near-infrared (NIR) multi-spectral camera, one of two workhorse lunar mapping cameras (the other being the UV/visible camera), provided {approximately}200 in spatial resolution at 400 km periselene, and a 39 km across-track swath. This 1.9 kg infrared camera using a 256 x 256 InSb FPA viewed reflected solar illumination from the lunar surface and lunar horizon in the 1 to 3 {micro}m wavelength region, extending lunar imagery and mineralogy studies into the near infrared. A description of this light-weight, low power NIR camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission`s primary objective for flight qualifying the sensors for future Department of Defense flights.

  4. Near-infrared imaging spectrometer onboard NEXTSat-1

    NASA Astrophysics Data System (ADS)

    Jeong, Woong-Seob; Park, Sung-Joon; Moon, Bongkon; Lee, Dae-Hee; Pyo, Jeonghyun; Park, Won-Kee; Park, Youngsik; Kim, Il-Joong; Ko, Kyeongyeon; Lee, Dukhang; Kim, Min Gyu; Kim, Minjin; Ko, Jongwan; Shin, Goo-Hwan; Chae, Jangsoo; Matsumoto, Toshio

    2016-07-01

    The NISS (Near-infrared Imaging Spectrometer for Star formation history) is the near-infrared instrument optimized to the first next generation of small satellite (NEXTSat-1) in Korea. The spectro-photometric capability in the near-infrared range is a unique function of the NISS. The major scientific mission is to study the cosmic star formation history in local and distant universe. For those purposes, the NISS will perform the large areal imaging spectroscopic survey for astronomical objects and low background regions. We have paid careful attention to reduce the volume and to increase the total throughput. The newly implemented off-axis optics has a wide field of view (2° x 2°) and a wide wavelength range from 0.9 to 3.8μm. The mechanical structure is designed to consider launching conditions and passive cooling of the telescope. The compact dewar after relay-lens module is to operate the infrared detector and spectral filters at 80K stage. The independent integration of relay-lens part and primary-secondary mirror assembly alleviates the complex alignment process. We confirmed that the telescope and the infrared sensor can be cooled down to around 200K and 80K, respectively. The engineering qualification model of the NISS was tested in the space environment including the launch-induced vibration and shock. The NISS will be expected to demonstrate core technologies related to the development of the future infrared space telescope in Korea.

  5. Multi-Wavelength Near Infrared Observations of Marum and Yasur Volcanoes, Vanuatu

    NASA Astrophysics Data System (ADS)

    Howell, Robert R.; Radebaugh, Jani; Lopes, Rosaly M.; Lorenz, Ralph D.; Turtle, Elizabeth P.

    2014-11-01

    To help understand and test models of thermal emission from planetary volcanoes, we obtained in May 2014 a variety of near-infrared observations of the very active Marum lava lake on Ambrym, Vanuatu, as well as the Strombolian activity at Yasur on Tanna. Our observations include high resolution images and movies made with standard and modified cameras and camcorders. In addition, to test the planetary emission models, which typically rely on multi-wavelength observations, we developed a small inexpensive prototype imager named "Kerby", which consists of three simultaneously active near-infrared cameras operating at 0.860, 0.775, and 0.675 microns, as well as a fourth visible wavelength RGB camera. This prototype is based on the Raspberry Pi and Pi-NoIR cameras. It can record full high definition video, and is light enough to be carried by backpack and run from batteries. To date we have concentrated on the analysis of the Marum data. During our observations of the 40 m diameter lava lake, convection was so vigorous that areas of thin crust formed only intermittently and persisted for tens of seconds to a few minutes at most. The convection pattern primarily consisted of two upwelling centers located about 8 m in from the margins on opposite sides of the lake. Horizontal velocities away from the upwelling centers were approximately 4 m/s. A hot bright margin roughly 0.4 m wide frequently formed around parts of the lake perimeter. We are in the process of establishing the absolute photometry calibration to obtain temperatures, temperature distributions, and magma cooling rates.

  6. Near-Infrared Absolute Photometric Imaging of the Uranian System

    NASA Astrophysics Data System (ADS)

    Baines, Kevin H.; Yanamandra-Fisher, Padmavati A.; Lebofsky, Larry A.; Momary, Thomas W.; Golisch, William; Kaminski, Charles; Wild, Walter J.

    1998-04-01

    We report the first multifilter set of absolutely calibrated near-infrared images of Uranus, its rings, and three major satellites-Titania, Ariel, and Miranda. Along with imagery utilizing the canonical K filter bandpass (effective wavelength 2.20 μm), absolutely calibrated images of the uranian system are presented for the first time for three additional filter bandpasses: J (1.27 μm), H (1.62 μm), and in a narrow bandpass (0.1 μm full-width-at-half-maximum) centered at 1.73 μm (hereafter designated H‧) particularly diagnostic of C-H stretch vibrational absorptions common in hydrocarbons. Multifilter-derived spectra of the southern ring ansa including the bright apoapse of the dominant ɛ ring show no absorptions due to condensable volatiles, including water, ammonia, and light (high H:C) hydrocarbons. Plausible near-infrared spherical geometric and single-scattering particle albedos consistent with Voyager-derived phase functions range from 0.069 to 0.102 and from 0.030 to 0.037, respectively. These are approximately 50% greater than visible values, consistent with the optical properties of charcoal, carbonaceous chondrite material, and the darkside of Iapetus, and consistent with the hypothesis that a primary component of the ring particles is high stoichiometric ratio C:H organics produced by charged-particle and/or photochemical weathering of methane clathrate and/or hydrocarbon ice material originating from nearby moonlets. Additional components consistent with the ring spectrum include silicates such as pyroxene, but not olivine. Analytical modeling of the ring structure indicates ɛ-ring near-infrared opacities of 0.37 ± 0.05 and 1.8 ± 0.3 at apoapsis and periapsis, respectively. Ariel is more than 25% brighter than Miranda and 15% brighter than Titania at all near-infrared wavelengths. Comparisons with UV-visible spectra by Karkoschka (1997,Icarus125, 348-363) show consistency with the hypothesis that the water-ice surfaces of Titania and Ariel

  7. Jupiter's Belt-Zone Boundary in Near-Infrared and Violet Light

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Mosaics of a belt-zone boundary near Jupiter's equator in violet (top panel) and near-infrared (bottom panel) light. The four images that make up each of these mosaics were taken within a few minutes of each other. Sunlight at 757 nanometers (near-infrared) penetrates deep into Jupiter's troposphere before being absorbed or scattered by clouds to the Galileo spacecraft. This wavelength reveals the features of the lower visible cloud deck. Sunlight at 415 nanometers (violet) is a scattered or absorbed to varying degrees in different parts of Jupiter's atmosphere depending on the types and concentrations of cloud particles and chemicals that color Jupiter's atmosphere. The near-infrared mosaic primarily shows cloud features. The violet mosaic has three distinct regions: it is brightest at the latitude of the jet (horizontally across the center of the mosaic), moderately bright north of the jet, and dark and patchy south of the jet.

    North is at the top. The mosaic covers latitudes -13 to +3 degrees and is centered at longitude 282 degrees West. The smallest resolved features are tens of kilometers in size. These images were taken on November 5th, 1996, at a range of 1.2 million kilometers by the Solid State Imaging system aboard NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the mission for NASA's Office of Space Science, Washington, DC.

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  8. The near-infrared properties of compact binary systems

    NASA Astrophysics Data System (ADS)

    Froning, Cynthia Suzanne

    I present H- and K-band light curves of the dwarf nova cataclysmic variable (CV), IP Peg, and the novalike CV, RW Tri, and an H-band light curve of the novalike CV, SW Sex. All three systems showed contributions from the late-type secondary star and the accretion disk, including a primary eclipse of the accretion disk by the secondary star and a secondary eclipse of the star by the disk. The ellipsoidal variations of the secondary star in IP Peg were modeled and subtracted from the data. The subtracted light curves show a pronounced double-hump variation, resembling those seen in the dwarf novae WZ Sge and AL Com. The primary eclipse was modeled using maximum entropy disk mapping techniques. The accretion disk has a flat intensity distribution and a low brightness temperature (Tbr ~= 3000-4000 K). Superimposed on the face of the disk is the bright spot, where the mass accretion stream impacts the disk; the position of the bright spot is different from the range of positions seen at visible wavelengths. The near-infrared accretion disk flux is dominated by optically thin emission. The eclipse depth is too shallow to be caused by a fully opaque accretion disk. The NIR light curves in RW Tri show a deep primary eclipse of the accretion disk, ellipsoidal variations from the secondary star, a secondary eclipse, and strong flickering in the disk flux. The depth of the secondary eclipse indicates that the accretion disk is opaque. The light curve also has a hump extending from φ = 0.1-0.9 which was successfully modeled as flux from the inner face of the secondary star when heated by a ~0.2 L Lsolar source. The radial brightness temperature profile of the outer disk is consistent with models of a disk in steady-state for a mass transfer rate of M~=5×10- 10 Msolaryr- 1 . At small disk radii, however, the brightness temperature profile is flatter than the steady-state model. The H-band light curve of SW Sex is dominated by emission from the accretion disk. As in RW Tri

  9. Visible and near-infrared observations of asteroid 2012 DA14 during its closest approach of February 15, 2013

    NASA Astrophysics Data System (ADS)

    de León, J.; Ortiz, J. L.; Pinilla-Alonso, N.; Cabrera-Lavers, A.; Alvarez-Candal, A.; Morales, N.; Duffard, R.; Santos-Sanz, P.; Licandro, J.; Pérez-Romero, A.; Lorenzi, V.; Cikota, S.

    2013-07-01

    Context. Near-Earth asteroid 2012 DA14 made its closest approach on February 15, 2013, when it passed at a distance of 27 700 km from the Earth's surface. It was the first time an asteroid of moderate size was predicted to approach that close to the Earth, becoming bright enough to permit a detailed study from ground-based telescopes. Aims: Asteroid 2012 DA14 was poorly characterized before its closest approach. The main objective of this work was to obtain new and valuable data to better understand its physical properties, and to evaluate the effects of such a close approach on the object. Methods: We acquired data using several telescopes on four Spanish observatories: the 10.4 m Gran Telescopio Canarias (GTC) and the 3.6 m Telescopio Nazionale Galileo (TNG), both in the El Roque de los Muchachos Observatory (ORM, La Palma); the 2.2 m CAHA telescope, in the Calar Alto Observatory (Almería); the f/3 0.77 m telescope in the La Hita Observatory (Toledo); and the f/8 1.5 m telescope in the Sierra Nevada Observatory (OSN, Granada). We obtained visible and near-infrared color photometry, visible spectra and time-series photometry. Results: Visible spectra together with visible and near-infrared color photometry of 2012 DA14 show that the object can be classified as an L-type asteroid, a rare spectral type among the asteroid population, with a composition similar to that of carbonaceous chondrites. The time-series photometry provides a rotational period of 8.95 ± 0.08 h after the closest approach, and there are indications that the object suffered a spin-up during this event. The large amplitude of the light curve suggests that the object is very elongated and irregular, with an equivalent diameter of around 18 m. We obtain an absolute magnitude of HR = 24.5 ± 0.2, corresponding to HV = 25.0 ± 0.2 in V. The GTC photometry also gives HV = 25.29 ± 0.14. Both values agree with the value listed at the Minor Planet Center (MPC) shortly after discovery, although HV is

  10. 77 FR 16925 - Medical Devices; Neurological Devices; Classification of the Near Infrared Brain Hematoma Detector

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ...; Classification of the Near Infrared Brain Hematoma Detector AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is classifying the Near Infrared (NIR) Brain... generic name Near Infrared (NIR) Brain Hematoma Detector, and it is identified as a noninvasive...

  11. Use of Near-Infrared Spectroscopy in Early Determination of Irreversible Hemorrhagic Shock

    DTIC Science & Technology

    2004-09-01

    infrared light. Unlike “pulse-oximetry,” NIR spectroscopy measures not only arterial, but...carotid artery. 2.2 Near- infrared spectroscopic methodology/ measurements : Near- infrared spectroscopy probes (Hutchinson Technology, Inc... Measurements 3rd resuscitation bolus (resus 3) 4th resuscitation bolus (resus 4) Measurements Measurements Use of Near- Infrared Spectroscopy

  12. [Detection of Adulteration in Milk Powder with Starch Near Infrared].

    PubMed

    Wang, Ning-ning; Shen, Bing-hui; Guan, Jian-jun; Zhao, Zhong-rui; Zhu, Ye-wei; Zhang, Lu-da; Yan, Yan-lu; Zheng, Yu-yan; Dong, Cheng-yu; Kang, Ding-ming

    2015-08-01

    Three China trademarks of milk powder called Mengniu, Yili, Wandashan were taken as testing samples. Each of them mixed varied amount of starch in different gradient, which were consisted of 32 adulterated milk powder samples mixed with starch, was taken as standard samples for constructing predicted model. To those 32 samples, the reflecting spectrum characteristics in middle wave of near infrared spectrum with Near Infrared Spectrum Analyzer (Micro NIR 1700) produced by JDSU Ltd. USA were collected for five repeats in five different days. The time span was nearly two months. Firstly, we build the model used the reflecting spectrum characteristics of those samples with biomimetic pattern recognition (BPR) arithmetic to do the qualitative analysis. The analysis included the reliability of testing result and stability of the model. When we took ninety percent as the evaluation threshold of testing result of CAR (Correct Acceptance Rate) and CRR (Correct Rejection Rate), the lowest starch content of adulterate milk powder in all tested samples which the tested result were bigger than that abovementioned threshold was designated CAR threshold (CAR-T) and CRR threshold (CRR-T). CAR means the correct rate of accepting a sample which is belong to itself, CRR means correct rate of refusing to accept a sample which is not belong to itself. The results were shown that, when we constructed a model based on the near infrared spectrum data from each of three China trademark milk powders, respectively, if we constructed a model with infrared spectrum data tested in a same day, both the CAR-T and CRR-T of adulterate starch content of a sample can reach 0.1% in predicting the remainder infrared spectrum data tested within a same day. The three China trademarks of milk powder had the same result. In addition, when we ignored the trademarks, put the spectrum data of adulterate milk powder samples mixed with the same content of starch of three China trademarks milk powder together

  13. Visible/near-infrared spectra of experimentally shocked plagioclase feldspars

    USGS Publications Warehouse

    Johnson, J. R.; Horz, F.

    2003-01-01

    High shock pressures cause structural changes in plagioclase feldspars such as mechanical fracturing and disaggregation of the crystal lattice at submicron scales, the formation of diaplectic glass (maskelynite), and genuine melting. Past studies of visible/ near-infrared spectra of shocked feldspars demonstrated few spectral variations with pressure except for a decrease in the depth of the absorption feature near 1250-1300 nm and an overall decrease in reflectance. New visible/near-infrared spectra (400-2500 nm) of experimentally shocked (17-56 GPa) albite- and anorthite-rich rock powders demonstrate similar trends, including the loss of minor hydrated mineral bands near 1410, 1930, 2250, and 2350 nm. However, the most interesting new observations are increases in reflectance at intermediate pressures, followed by subsequent decreases in reflectance at higher pressures. The amount of internal scattering and overall sample reflectance is controlled by the relative proportions of micro-fractures, submicron grains, diaplectic glass, and melts formed during shock metamorphism. We interpret the observed reflectance increases at intermediate pressures to result from progressively larger proportions of submicron feldspar grains and diaplectic glass. The ensuing decreases in reflectance occur after diaplectic glass formation is complete and the proportion of genuine melt inclusions increases. The pressure regimes over which these reflectance variations occur differ between albite and anorthite, consistent with thermal infrared spectra of these samples and previous studies of shocked feldspars. These types of spectral variations associated with different peak shock pressures should be considered during interpretation and modeling of visible/near-infrared remotely sensed spectra of planetary and asteroidal surfaces.

  14. Near-infrared imaging of FSC 10214+4724 with the W. M. Keck Telescope

    NASA Technical Reports Server (NTRS)

    Matthews, K.; Soifer, B. T.; Nelson, J.; Boesgaard, H.; Graham, J. R.; Harrison, W.; Irace, W.; Jernigan, G.; Larkin, J. E.; Lewis, H.

    1994-01-01

    Near-infrared observations of the z = 2.286 IRAS source FSC 10214+4724, made with the near-infrared camera on the W. M. Keck Telescope, are reported. Deep broad-band images at 2.15 and 1.27 micrometers, and narrow-band images at 2.165 and 2.125 micrometers with 0.6 sec to 0.9 sec seeing show that FSC 10214+4724 consists of at least three distinct components in a compact group of galaxies. The source of the infrared luminosity appears to be in a strongly interacting galaxy that has a luminosity of approximately 100 times that of a present-day L* galaxy. The interaction suggests and 'age' of this galaxy of approximately equal to 10(exp 9) yr. The H-alpha emission is resolved as a source of diameter approximately equal to 5 kpc, suggesting that a starburst contributes to the observed H-alpha emission. There is an excess of objects in the FSC 10214+4724 field that could represent galaxies in an associated cluster.

  15. Near-Infrared Fluorescence-Enhanced Optical Tomography

    PubMed Central

    2016-01-01

    Fluorescence-enhanced optical imaging using near-infrared (NIR) light developed for in vivo molecular targeting and reporting of cancer provides promising opportunities for diagnostic imaging. The current state of the art of NIR fluorescence-enhanced optical tomography is reviewed in the context of the principle of fluorescence, the different measurement schemes employed, and the mathematical tools established to tomographically reconstruct the fluorescence optical properties in various tissue domains. Finally, we discuss the recent advances in forward modeling and distributed memory parallel computation to provide robust, accurate, and fast fluorescence-enhanced optical tomography. PMID:27803924

  16. Transrectal Near-Infrared Optical Tomography for Prostate Imaging

    DTIC Science & Technology

    2011-03-01

    2009. CA Cancer J Clin. 2009;59:225-249. 2. Hodge KK, McNeal JE, Stamey TA. Ultrasound guided transrectal core biopsies of the palpably abnormal...near-infrared spectroscopy: pilot results in the breast," Radiology 218, 261-266 (2001). [4] Tara Yates, Jeremy C Hebden, Adam Gibson, Nick ...digital rectal examination as screening tests for prostate carcinoma,” J Am Board Fam Pract.; 16(2):95- 101 (2003). 3. Hodge KK, McNeal JE, Stamey TA

  17. Monitoring Key Parameters in Bioprocesses Using Near-Infrared Technology

    PubMed Central

    Tamburini, Elena; Marchetti, Maria Gabriella; Pedrini, Paola

    2014-01-01

    Near-infrared spectroscopy (NIRS) is known to be a rapid and non-destructive technique for process monitoring. Bioprocesses are usually complex, from both the chemical (ill-defined medium composition) and physical (multiphase matrix) aspects, which poses an additional challenge to the development of robust calibrations. We investigated the use of NIRS for on-line and in-line monitoring of cell, substrate and product concentrations, during aerobic and anaerobic bacterial fermentations, in different fermentation strategies. Calibration models were built up, then validated and used for the automated control of fermentation processes. The capability of NIR in-line to discriminate among differently shaped bacteria was tested. PMID:25313494

  18. Monitoring key parameters in bioprocesses using near-infrared technology.

    PubMed

    Tamburini, Elena; Marchetti, Maria Gabriella; Pedrini, Paola

    2014-10-13

    Near-infrared spectroscopy (NIRS) is known to be a rapid and non-destructive technique for process monitoring. Bioprocesses are usually complex, from both the chemical (ill-defined medium composition) and physical (multiphase matrix) aspects, which poses an additional challenge to the development of robust calibrations. We investigated the use of NIRS for on-line and in-line monitoring of cell, substrate and product concentrations, during aerobic and anaerobic bacterial fermentations, in different fermentation strategies. Calibration models were built up, then validated and used for the automated control of fermentation processes. The capability of NIR in-line to discriminate among differently shaped bacteria was tested.

  19. Near Infrared Spectral Determination of Human Tissue pH.

    DTIC Science & Technology

    1995-10-01

    Continuous Tissue pH Monitory in the Human Fetus During Labor", Obstet . Gynecol ., 55:523, 1980. 23. [Lemer 82] Lemer, H., et al., "Measurement of Glucose...Umbilical Blood pH", Am. J. Obstet . Gynecol ., 128: 901-903, 1977. 38. [Weyer 85] Weyer, L G., "Near Infrared Spectroscopy of Organic Substances," Applied...Patterns and Tissue pH in the Human Fetus", Am. J. Obstet . Gynecol ., 134:685-690, 1979. 24 Appendix I An Estimation Extension of the FKNN Algorithm In

  20. Near-infrared spectra of Jupiter, Saturn, and Uranus

    NASA Technical Reports Server (NTRS)

    Potter, A. E.

    1974-01-01

    Near infrared spectra of Jupiter, Saturn, and Uranus were measured at resolutions higher than previously available in the range from 6,000 to 10,750/cm. The resolution was 0.5/cm for Jupiter and Saturn, and 32/cm for Uranus. The spectra are presented both individually and as ratio spectra, in which the planetary spectra are divided by the solar spectrum. The Uranus spectrum is shown with Saturn, Jupiter, and Sun spectra reduced to the same resolution so that Uranus can be compared with the other outer planets. The high resolution Saturn, Jupiter, and Sun spectra are presented in parallel plots to simplify comparisons between them.

  1. Near infrared fluorescence for image-guided surgery

    PubMed Central

    2012-01-01

    Near infrared (NIR) image-guided surgery holds great promise for improved surgical outcomes. A number of NIR image-guided surgical systems are currently in preclinical and clinical development with a few approved for limited clinical use. In order to wield the full power of NIR image-guided surgery, clinically available tissue and disease specific NIR fluorophores with high signal to background ratio are necessary. In the current review, the status of NIR image-guided surgery is discussed along with the desired chemical and biological properties of NIR fluorophores. Lastly, tissue and disease targeting strategies for NIR fluorophores are reviewed. PMID:23256079

  2. Optical absorption near infrared and EPR studies of mottramite

    NASA Astrophysics Data System (ADS)

    Lakshmi Reddy, S.; Reddy, K. N. M.; Siva Reddy, G.; Endo, Tamio; Frost, R. L.

    2010-06-01

    Mottramite mineral from Tsumeb Corporation Mine, Tsumeb, Otavi, Namibia, is investigated in this present work. The mineral contains vanadium and copper contents of 22.73% and 16.84% by weight, respectively, as V2O5 and CuO. An electron paramagnetic resonance (EPR) study confirmed the presence of Cu(II) with g = 2.2. The optical absorption spectrum of mottramite indicates that Cu(II) is present in a rhombic environment. Near infrared results are due to water fundamentals.

  3. Review of near-infrared methods for wound assessment

    NASA Astrophysics Data System (ADS)

    Sowa, Michael G.; Kuo, Wen-Chuan; Ko, Alex C.-T.; Armstrong, David G.

    2016-09-01

    Wound management is a challenging and costly problem that is growing in importance as people are living longer. Instrumental methods are increasingly being relied upon to provide objective measures of wound assessment to help guide management. Technologies that employ near-infrared (NIR) light form a prominent contingent among the existing and emerging technologies. We review some of these technologies. Some are already established, such as indocyanine green fluorescence angiography, while we also speculate on others that have the potential to be clinically relevant to wound monitoring and assessment. These various NIR-based technologies address clinical wound management needs along the entire healing trajectory of a wound.

  4. Near-infrared spectroscopy of comet Bradfield 1979l

    NASA Astrophysics Data System (ADS)

    Danks, A. C.; Dennefeld, M.

    1981-02-01

    Spectroscopic observations using an unintensified reticon detector are presented of comet Bradfield 1979l, covering the spectral region from 6100 to 11,000 A. The red CN 2-0, 3-1, and 1-0 bands are easily identified in the nuclear region and their intensity ratios are used to determine that the vibrational transition probability for the ground electronic state lies between 0.32 and 1/sec. The CN 2-0 and 1-0 bands are also present in the coma. The interest in simultaneous measurements of the near-infrared and space UV of future comets is pointed out.

  5. Near-infrared spectral imaging Michelson interferometer for astronomical applications

    NASA Technical Reports Server (NTRS)

    Wells, C. W.; Potter, A. E.; Morgan, T. H.

    1980-01-01

    The design and operation of an imaging Michelson interferometer-spectrometer used for near-infrared (0.8 micron to 2.5 microns) spectral imaging are reported. The system employs a rapid scan interferometer modified for stable low resolution (250/cm) performance and a 42 element PbS linear detector array. A microcomputer system is described which provides data acquisition, coadding, and Fourier transformation for near real-time presentation of the spectra of all 42 scene elements. The electronic and mechanical designs are discussed and telescope performance data presented.

  6. Cartilage-Specific Near-Infrared Fluorophores for Biomedical Imaging.

    PubMed

    Hyun, Hoon; Owens, Eric A; Wada, Hideyuki; Levitz, Andrew; Park, GwangLi; Park, Min Ho; Frangioni, John V; Henary, Maged; Choi, Hak Soo

    2015-07-20

    A novel class of near-infrared fluorescent contrast agents was developed. These agents target cartilage with high specificity and this property is inherent to the chemical structure of the fluorophore. After a single low-dose intravenous injection and a clearance time of approximately 4 h, these agents bind to all three major types of cartilage (hyaline, elastic, and fibrocartilage) and perform equally well across species. Analysis of the chemical structure similarities revealed a potential pharmacophore for cartilage targeting. Our results lay the foundation for future improvements in tissue engineering, joint surgery, and cartilage-specific drug development.

  7. Near-infrared spectroscopy. Innovative technology summary report

    SciTech Connect

    Not Available

    1999-07-01

    A near-infrared (NIR) spectroscopy system with a remote fiber-optic probe was developed and demonstrated to measure the water content of high-level radioactive wastes from the underground storage tanks at the Hanford Site in richland Washington. The technology was developed as a cost-effective and safer alternative to the thermogravimetric analysis (TGA) technique in use as the baseline. This work was supported by the Tanks Focus Area (TFA) within the Department of Energy`s (DOE) Office of Science and Technology (OST) in cooperation with the Hanford Tank Waste Remediation System (TWRS) Program.

  8. JWST Near-Infrared Detectors: Latest Test Results

    NASA Technical Reports Server (NTRS)

    Smith, Erin C.; Rauscher, Bernard J.; Alexander, David; Brambora, Clifford K.; Chiao, Meng; Clemons, Brian L.; Derro, Rebecca; Engler, Chuck; Fox, Ori; Garrison, Matthew B.; Greenhouse, Matthew A.; Henegar, Greg; Hill, Robert J.; Johnson, Thomas; Lavaque, Dodolfo J.; Lindler, Don J.; Manthripragada, Sridhar S.; Marshall, Cheryl; Mott, Brent; Parr, Thomas M.; Roher, Wayne D.; Shakoorzadeh, Kamdin B.; Schnurr, Richard; Smith, Miles; Waczynski, Augustyn

    2009-01-01

    The James Webb Space Telescope, an infrared-optimized space telescope being developed by NASA for launch in 2013, will utilize cutting-edge detector technology in its investigation of fundamental questions in astrophysics. JWST's near infrared spectrograph, NIRSpec utilizes two 2048 x 2048 HdCdTe arrays with Sidecar ASIC readout electronics developed by Teledyne to provide spectral coverage from 0.6 microns to 5 microns. We present recent test and calibration results for the NIRSpec flight arrays as well as data processing routines for noise reduction and cosmic ray rejection.

  9. [Application of near infrared spectroscopy in analysis of wood properties].

    PubMed

    Yao, Sheng; Pu, Jun-wen

    2009-04-01

    There is substantial interest in the improvement of wood properties through genetic selection or a change in silviculture prescription. Tree breeding purpose requires measurement of a large number of samples. However, traditional methods of assessing wood properties are both time consuming and destructive, limiting the numbers of samples that can be processed, so new method would be needed to find. Near infrared spectroscopy (NIR) is an advanced spectroscopic tool for nondestructive evaluation of wood and it can quickly, accurately estimate the properties of increment core, solid wood or wood meal. The present paper reviews the advances in the research on the wood chemistry properties and anatomical properties using NIR.

  10. Investigation of a near-infrared-ray computed tomography scanner

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Oda, Yasuyuki; Satoi, Yuichi; Yamaguchi, Satoshi; Ishii, Tomotaka; Hagiwara, Osahiko; Matsukiyo, Hiroshi; Watanabe, Manabu; Kusachi, Shinya

    2016-10-01

    In the near-infrared-ray computed tomography (NIR-CT) scanner, NIR rays are produced from a light-emitting diode (LED) and detected using an NIR phototransistor (PT). The wavelengths of the LED peak intensity and the PT high sensitivity in the data table are both 940 nm. The photocurrents flowing through the PTR are converted into voltages using an emitter-follower circuit, and the output voltages are sent to a personal computer through an analog-digital converter. The NIR projection curves for tomography are obtained by repeated linear scans and rotations of the object, and the scanning is conducted in both directions of its movement.

  11. Noninvasively measuring the hemodynamic effects of massage on skeletal muscle: a novel hybrid near-infrared diffuse optical instrument.

    PubMed

    Munk, Niki; Symons, Brock; Shang, Yu; Cheng, Ran; Yu, Guoqiang

    2012-01-01

    Increase in tissue blood flow is one of the most acknowledged potential effects of massage; however, actual research studies examining this phenomenon are inconsistent and inconclusive. One possible reason for continued uncertainty regarding this topic is methodology, specifically how tissue blood flow is measured because limitations exist in previously utilized technologies. Near-infrared spectroscopy (NIRS) affords massage researchers a versatile and non-invasive measurement option by providing dynamic information on oxy- and deoxy-hemoglobin concentrations, total hemoglobin concentration, and blood oxygen saturation in deep tissue. Near-infrared diffuse correlation spectroscopy (DCS) is an innovative technique for continuous non-invasive measurement of blood flow in deep tissue. The combination of these two technologies has resulted in a novel hybrid diffuse optical instrument for simultaneous measurement of limb muscle blood flow and oxygenation. The purposes of this short report are to review previous blood flow measurement techniques and limitations in massage therapy research, introduce a novel hybrid near-infrared diffuse optical instrument that addresses previous limitations in the assessment of hemodynamic properties, outline a proposed massage therapy pilot study utilizing the novel measurement technology, and present sample data from a pilot participant using the introduced novel technology.

  12. Near-infrared detection of WD 0806-661 B with the Hubble space telescope

    SciTech Connect

    Luhman, K. L.; Esplin, T. L.; Morley, C. V.; Burgasser, A. J.; Bochanski, J. J.

    2014-10-10

    WD 0806-661 B is one of the coldest known brown dwarfs (T {sub eff} = 300-345 K) based on previous mid-infrared photometry from the Spitzer Space Telescope. In addition, it is a benchmark for testing theoretical models of brown dwarfs because its age and distance are well constrained via its primary star (2 ± 0.5 Gyr, 19.2 ± 0.6 pc). We present the first near-infrared detection of this object, which has been achieved through F110W imaging (∼Y + J) with the Wide Field Camera 3 on board the Hubble Space Telescope. We measure a Vega magnitude of m {sub 110} = 25.70 ± 0.08, which implies J ∼ 25.0. When combined with the Spitzer photometry, our estimate of J helps to better define the empirical sequence of the coldest brown dwarfs in M {sub 4.5} versus J – [4.5]. The positions of WD 0806-661 B and other Y dwarfs in that diagram are best matched by the cloudy models of Burrows et al. and the cloudless models of Saumon et al., both of which employ chemical equilibrium. The calculations by Morley et al. for 50% cloud coverage differ only modestly from the data. Spectroscopy would enable a more stringent test of the models, but based on our F110W measurement, such observations are currently possible only with Hubble, and would require at least ∼10 orbits to reach a signal-to-noise ratio of ∼5.

  13. Near-infrared spectroscopy as a tool for driving research.

    PubMed

    Liu, Tao; Pelowski, Matthew; Pang, Changle; Zhou, Yuanji; Cai, Jianfeng

    2016-03-01

    Driving a motor vehicle requires various cognitive functions to process surrounding information, to guide appropriate actions, and especially to respond to or integrate with numerous contextual and perceptual hindrances or risks. It is, thus, imperative to examine driving performance and road safety from a perspective of cognitive neuroscience, which considers both the behaviour and the functioning of the brain. However, because of technical limitations of current brain imaging approaches, studies have primarily adopted driving games or simulators to present participants with simulated driving environments that may have less ecological validity. Near-infrared spectroscopy (NIRS) is a relatively new, non-invasive brain-imaging technique allowing measurement of brain activations in more realistic settings, even within real motor vehicles. This study reviews current NIRS driving research and explores NIRS' potential as a new tool to examine driving behaviour, along with various risk factors in natural situations, promoting our understanding about neural mechanisms of driving safety. Practitioner Summary: Driving a vehicle is dependent on a range of neurocognitive processing abilities. Near-infrared spectroscopy (NIRS) is a non-invasive brain-imaging technique allowing measurement of brain activation even in on-road studies within real motor vehicles. This study reviews current NIRS driving research and explores the potential of NIRS as a new tool to examine driving behaviour.

  14. NIRS3: The Near Infrared Spectrometer on Hayabusa2

    NASA Astrophysics Data System (ADS)

    Iwata, Takahiro; Kitazato, Kohei; Abe, Masanao; Ohtake, Makiko; Arai, Takehiko; Arai, Tomoko; Hirata, Naru; Hiroi, Takahiro; Honda, Chikatoshi; Imae, Naoya; Komatsu, Mutsumi; Matsunaga, Tsuneo; Matsuoka, Moe; Matsuura, Shuji; Nakamura, Tomoki; Nakato, Aiko; Nakauchi, Yusuke; Osawa, Takahito; Senshu, Hiroki; Takagi, Yasuhiko; Tsumura, Kohji; Takato, Naruhisa; Watanabe, Sei-ichiro; Barucci, Maria Antonietta; Palomba, Ernesto; Ozaki, Masanobu

    2017-03-01

    NIRS3: The Near Infrared Spectrometer is installed on the Hayabusa2 spacecraft to observe the target C-type asteroid 162173 Ryugu at near infrared wavelengths of 1.8 to 3.2 μm. It aims to obtain reflectance spectra in order to detect absorption bands of hydrated and hydroxide minerals in the 3 μm-band. We adopted a linear-image sensor with indium arsenide (InAs) photo diodes and a cooling system with a passive radiator to achieve an optics temperature of 188 K ( -85°C), which enables to retaining sufficient sensitivity and noise level in the 3 μm wavelength region. We conducted ground performance tests for the NIRS3 flight model (FM) to confirm its baseline specifications. The results imply that the properties such as the signal-to-noise ratio (SNR) conform to scientific requirements to determine the degree of aqueous alteration, such as CM or CI chondrite, and the stage of thermal metamorphism on the asteroid surface.

  15. Near infrared photochemistry of pyruvic acid in aqueous solution.

    PubMed

    Larsen, Molly C; Vaida, Veronica

    2012-06-21

    Recent experimental and theoretical results have suggested that organic acids such as pyruvic acid, can be photolyzed in the ground electronic state by the excitation of the OH stretch vibrational overtone. These overtones absorb in the near-infrared and visible regions of the spectrum where the solar photons are plentiful and could provide a reaction pathway for the organic acids and alcohols that are abundant in the earth's atmosphere. In this paper the overtone initiated photochemistry of aqueous pyruvic acid is investigated by monitoring the evolution of carbon dioxide. In these experiments CO(2) is being produced by excitation in the near-infrared, between 850 nm and ∼1150 nm (11,765-8696 cm(-1)), where the second OH vibrational overtone (Δν = 3) of pyruvic acid is expected to absorb. These findings show not only that the overtone initiated photochemical decarboxylation reaction occurs but also that in the aqueous phase it occurs at a lower energy than was predicted for the overtone initiated reaction of pyruvic acid in the gas phase (13,380 cm(-1)). A quantum yield of (3.5 ± 1.0) × 10(-4) is estimated, suggesting that although this process does occur, it does so with a very low efficiency.

  16. Length-free near infrared measurement of newborn malnutrition

    NASA Astrophysics Data System (ADS)

    Mustafa, Fatin Hamimi; Bek, Emily J.; Huvanandana, Jacqueline; Jones, Peter W.; Carberry, Angela E.; Jeffery, Heather E.; Jin, Craig T.; McEwan, Alistair L.

    2016-11-01

    Under-nutrition in neonates can cause immediate mortality, impaired cognitive development and early onset adult disease. Body fat percentage measured using air-displacement-plethysmography has been found to better indicate under-nutrition than conventional birth weight percentiles. However, air-displacement-plethysmography equipment is expensive and non-portable, so is not suited for use in developing communities where the burden is often the greatest. We proposed a new body fat measurement technique using a length-free model with near-infrared spectroscopy measurements on a single site of the body - the thigh. To remove the need for length measurement, we developed a model with five discrete wavelengths and a sex parameter. The model was developed using air-displacement-plethysmography measurements in 52 neonates within 48 hours of birth. We identified instrumentation required in a low-cost LED-based screening device and incorporated a receptor device that can increase the amount of light collected. This near-infrared method may be suitable as a low cost screening tool for detecting body fat levels and monitoring nutritional interventions for malnutrition in neonates and young children in resource-constrained communities.

  17. Near infrared transmission through clothing: applications in sensing and screening

    NASA Astrophysics Data System (ADS)

    Hutchins, D. A.; Canal, C. M.; Saleem, A.; Davis, L. A. J.; Green, R. J.

    2011-11-01

    Experiments have been performed to demonstrate that near infrared (NIR) transmission through a wide range of clothing materials is possible. Studies have shown that the characteristics of NIR transmission are affected by both the type of fibre used, and the weave pattern. A series of experiments has indicated that NIR transmission is also dependent on other variables such as fabric porosity and dye colour. It is shown that, in many cases, transmission coefficients are sufficiently high that imaging and spectroscopy of objects hidden behind clothing samples should be possible. However, while transmission through clothing at NIR wavelengths in the 750-1,700 nm range is often more effective than in the visible or IR regions, the fabrics themselves will modify the transmitted signal in terms of spatial effects, intensity and spectral content. The paper also describes the possible use of near infrared signals to identify objects that are hidden behind clothing layers. This can be done using spectroscopy. It is important, however, to distinguish the various contributions that exist within the backscattered signal. A set of careful laboratory experiments have demonstrated that transmission through a set of different clothing fabrics does modify the spectral content of signals, but that the spectrum of a particular chemical can still be identified, provided certain steps are taken. These involve a set of careful calibration measurements, and the use of processing techniques for the retrieval of data. It will be shown that this is possible for both granular solids and selected liquids.

  18. Wavelet minimum description length detrending for near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Jang, Kwang Eun; Tak, Sungho; Jung, Jinwook; Jang, Jaeduck; Jeong, Yong; Ye, Jong Chul

    2009-05-01

    Near-infrared spectroscopy (NIRS) can be employed to investigate brain activities associated with regional changes of the oxy- and deoxyhemoglobin concentration by measuring the absorption of near-infrared light through the intact skull. NIRS is regarded as a promising neuroimaging modality thanks to its excellent temporal resolution and flexibility for routine monitoring. Recently, the general linear model (GLM), which is a standard method for functional MRI (fMRI) analysis, has been employed for quantitative analysis of NIRS data. However, the GLM often fails in NIRS when there exists an unknown global trend due to breathing, cardiac, vasomotion, or other experimental errors. We propose a wavelet minimum description length (Wavelet-MDL) detrending algorithm to overcome this problem. Specifically, the wavelet transform is applied to decompose NIRS measurements into global trends, hemodynamic signals, and uncorrelated noise components at distinct scales. The minimum description length (MDL) principle plays an important role in preventing over- or underfitting and facilitates optimal model order selection for the global trend estimate. Experimental results demonstrate that the new detrending algorithm outperforms the conventional approaches.

  19. Ischemic stroke assessment with near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Weiguo; Li, Pengcheng; Zeng, Shaoqun; Luo, Qingming; Hu, Bo

    1999-09-01

    Many authors have elucidated the theory about oxygenated hemoglobin, deoxygenated hemoglobin absorption in near-infrared spectrum. And the theory has opened a window to measure the hemodynamic changes caused by stroke. However, no proper animal model still has established to confirm the theory. The aim of this study was to validate near-infrared cerebral topography (NCT) as a practical tool and to try to trace the focal hemodynamic changes of ischemic stroke. In the present study, middle cerebral artery occlusion model and the photosensitizer induced intracranial infarct model had been established. NCT and functional magnetic resonance image (fMRI) were obtained during pre- and post-operation. The geometric shape and infarct area of NCT image was compared with the fMRI images and anatomical samples of each rat. The results of two occlusion models in different intervene factors showed the NCT for infarct focus matched well with fMRI and anatomic sample of each rats. The instrument might become a practical tool for short-term prediction of stroke and predicting the rehabilitation after stroke in real time.

  20. Photothermal response of near-infrared-absorbing NanoGUMBOS.

    PubMed

    Dumke, Jonathan C; Qureshi, Ammar; Hamdan, Suzana; El-Zahab, Bilal; Das, Susmita; Hayes, Daniel J; Boldor, Dorin; Rupnik, Kresimir; Warner, Isiah M

    2014-01-01

    The photothermal properties of several near-infrared-absorbing nanoparticles derived from group of uniform materials based on organic salts (GUMBOS) and composed of cationic dyes coupled with biocompatible anions are evaluated. These nanoparticles were synthesized using a reprecipitation method performed at various pH values: 2.0, 5.0, 7.0, 9.0, and 11.0. The cations for the nanoparticles derived from GUMBOS (nanoGUMBOS), [1048] and [1061], have absorbance maxima at wavelengths overlapping with human soft tissue absorbance minima. Near-infrared-absorbing nanoGUMBOS excited with a 1064 nm continuous laser led to heat generation, with an average temperature increase of 20.4 ± 2.7 °C. Although the [1061][Deoxycholate] nanoGUMBOS generated the highest temperature increase (23.7 ± 2.4 °C), it was the least photothermally efficient compound (13.0%) due to its relatively large energy band gap of 0.892 eV. The more photothermally efficient compound [1048][Ascorbate] (64.4%) had a smaller energy band gap of 0.861 eV and provided an average photothermal temperature increase of 21.0 ± 2.1 °C.

  1. Near-infrared spectral methods for noninvasively measuring blood glucose

    NASA Astrophysics Data System (ADS)

    Fei, Sun; Kong, Deyi; Mei, Tao; Tao, Yongchun

    2004-05-01

    Determination of blood glucose concentrations in diabetic patients is a frequently occurring procedure and an important tool for diabetes management. Use of noninvasive detection techniques can relieve patients from the pain of frequent finger pokes and avoid the infection of disease via blood. This thesis discusses current research and analyzes the advantages and shortages of different measurement methods, including: optical methods (Transmission, Polarimetry and scattering), then, we give emphasis to analyze the technology of near-infrared (NIR) spectra. NIR spectral range 700 nm ~2300 nm was used because of its good transparency for biological tissue and presence of glucose absorption band. In this work, we present an outline of noninvasive blood glucose measurement. A near-infrared light beam is passed through the finger, and the spectral components of the emergent beam are measured using spectroscopic techniques. The device includes light sources having the wavelengths of 600 nm - 1800 nm to illuminate the tissue. Receptors associated with the light sources for receiving light and generating a transmission signal representing the light transmitted are also provided. Once a transmission signal is received by receptors, and the high and low values from each of the signals are stored in the device. The averaged values are then analyzed to determine the glucose concentration, which is displayed on the device.

  2. Length-free near infrared measurement of newborn malnutrition

    PubMed Central

    Mustafa, Fatin Hamimi; Bek, Emily J.; Huvanandana, Jacqueline; Jones, Peter W.; Carberry, Angela E.; Jeffery, Heather E.; Jin, Craig T.; McEwan, Alistair L.

    2016-01-01

    Under-nutrition in neonates can cause immediate mortality, impaired cognitive development and early onset adult disease. Body fat percentage measured using air-displacement-plethysmography has been found to better indicate under-nutrition than conventional birth weight percentiles. However, air-displacement-plethysmography equipment is expensive and non-portable, so is not suited for use in developing communities where the burden is often the greatest. We proposed a new body fat measurement technique using a length-free model with near-infrared spectroscopy measurements on a single site of the body - the thigh. To remove the need for length measurement, we developed a model with five discrete wavelengths and a sex parameter. The model was developed using air-displacement-plethysmography measurements in 52 neonates within 48 hours of birth. We identified instrumentation required in a low-cost LED-based screening device and incorporated a receptor device that can increase the amount of light collected. This near-infrared method may be suitable as a low cost screening tool for detecting body fat levels and monitoring nutritional interventions for malnutrition in neonates and young children in resource-constrained communities. PMID:27824061

  3. Infrared and Near-Infrared Spectroscopy of Acetylacetone and Hexafluoroacetylacetone.

    PubMed

    Howard, Daryl L; Kjaergaard, Henrik G; Huang, Jing; Meuwly, Markus

    2015-07-23

    The infrared and near-infrared spectra of acetylacetone, acetylacetone-d8, and hexafluoroacetylacetone are characterized from experiment and computations at different levels. In the fundamental region, the intramolecular hydrogen bonded OH-stretching transition is clearly observed as a very broad band with substantial structure and located at significantly lower frequency compared to common OH-stretching frequencies. There is no clear evidence for OH-stretching overtone transitions in the near-infrared region, which is dominated by the CH-stretching overtones of the methine and methyl CH bonds. From molecular dynamics (MD) simulations, with a potential energy surface previously validated for tunneling splittings, the infrared spectra are determined and used in assigning the experimentally measured ones. It is found that the simulated spectrum in the region associated with the proton transfer mode is exquisitely sensitive to the height of the barrier for proton transfer. Comparison of the experimental and the MD simulated spectra establishes that the barrier height is around 2.5 kcal/mol, which favorably compares with 3.2 kcal/mol obtained from high-level electronic structure calculations.

  4. Micro-electro-mechanically switchable near infrared complementary metamaterial absorber

    SciTech Connect

    Pitchappa, Prakash; Pei Ho, Chong; Kropelnicki, Piotr; Singh, Navab; Kwong, Dim-Lee; Lee, Chengkuo

    2014-05-19

    We experimentally demonstrate a micro-electro-mechanically switchable near infrared complementary metamaterial absorber by integrating the metamaterial layer to be the out of plane movable microactuator. The metamaterial layer is electrostatically actuated by applying voltage across the suspended complementary metamaterial layer and the stationary bottom metallic reflector. Thus, the effective spacing between the metamaterial layer and bottom metal reflector is varied as a function of applied voltage. With the reduction of effective spacing between the metamaterial and reflector layers, a strong spectral blue shift in the peak absorption wavelength can be achieved. With spacing change of 300 nm, the spectral shift of 0.7 μm in peak absorption wavelength was obtained for near infrared spectral region. The electro-optic switching performance of the device was characterized, and a striking switching contrast of 1500% was achieved at 2.1 μm. The reported micro-electro-mechanically tunable complementary metamaterial absorber device can potentially enable a wide range of high performance electro-optical devices, such as continuously tunable filters, modulators, and electro-optic switches that form the key components to facilitate future photonic circuit applications.

  5. Airborne laser systems for atmospheric sounding in the near infrared

    NASA Astrophysics Data System (ADS)

    Sabatini, Roberto; Richardson, Mark A.; Jia, Huamin; Zammit-Mangion, David

    2012-06-01

    This paper presents new techniques for atmospheric sounding using Near Infrared (NIR) laser sources, direct detection electro-optics and passive infrared imaging systems. These techniques allow a direct determination of atmospheric extinction and, through the adoption of suitable inversion algorithms, the indirect measurement of some important natural and man-made atmospheric constituents, including Carbon Dioxide (CO2). The proposed techniques are suitable for remote sensing missions performed by using aircraft, satellites, Unmanned Aerial Vehicles (UAV), parachute/gliding vehicles, Roving Surface Vehicles (RSV), or Permanent Surface Installations (PSI). The various techniques proposed offer relative advantages in different scenarios. All are based on measurements of the laser energy/power incident on target surfaces of known geometric and reflective characteristics, by means of infrared detectors and/or infrared cameras calibrated for radiance. Experimental results are presented relative to ground and flight trials performed with laser systems operating in the near infrared (NIR) at λ = 1064 nm and λ = 1550 nm. This includes ground tests performed with 10 Hz and 20 KHz PRF NIR laser systems in a variety of atmospheric conditions, and flight trials performed with a 10 Hz airborne NIR laser system installed on a TORNADO aircraft, flying up to altitudes of 22,000 ft above ground level. Future activities are planned to validate the atmospheric retrieval algorithms developed for CO2 column density measurements, with emphasis on aircraft related emissions at airports and other high air-traffic density environments.

  6. In Vitro Photodynamic Therapy and Quantitative Structure–Activity Relationship Studies with Stable Synthetic Near-Infrared-Absorbing Bacteriochlorin Photosensitizers

    PubMed Central

    Huang, Ying-Ying; Mroz, Pawel; Zhiyentayev, Timur; Sharma, Sulbha K.; Balasubramanian, Thiagarajan; Ruzié, Christian; Krayer, Michael; Fan, Dazhong; Borbas, K. Eszter; Yang, Eunkyung; Kee, Hooi Ling; Kirmaier, Christine; Diers, James R.; Bocian, David F.; Holten, Dewey; Lindsey, Jonathan S.; Hamblin, Michael R.

    2010-01-01

    Photodynamic therapy (PDT) is a rapidly developing approach to treating cancer that combines harmless visible and near-infrared light with a nontoxic photoactivatable dye, which upon encounter with molecular oxygen generates the reactive oxygen species that are toxic to cancer cells. Bacteriochlorins are tetrapyrrole compounds with two reduced pyrrole rings in the macrocycle. These molecules are characterized by strong absorption features from 700 to >800 nm, which enable deep penetration into tissue. This report describes testing of 12 new stable synthetic bacteriochlorins for PDT activity. The 12 compounds possess a variety of peripheral substituents and are very potent in killing cancer cells in vitro after illumination. Quantitative structure–activity relationships were derived, and subcellular localization was determined. The most active compounds have both low dark toxicity and high phototoxicity. This combination together with near-infrared absorption gives these bacteriochlorins great potential as photosensitizers for treatment of cancer. PMID:20441223

  7. A Near-Infrared BiFC Reporter for In Vivo Imaging of Protein-Protein Interactions

    PubMed Central

    Filonov, Grigory S.; Verkhusha, Vladislav V.

    2013-01-01

    SUMMARY Studies of protein-protein interactions deep in organs and in whole mammals have been hindered by a lack of genetically encoded fluorescent probes in near-infrared region for which mammalian tissues are the most transparent. We have used a near-infrared fluorescent protein iRFP engineered from a bacterial phytochrome as the template to develop an in vivo split fluorescence complementation probe. The domain architecture-based rational design resulted in an iSplit reporter with the spectra optimal for whole-body imaging, high photostability, and high complementation contrast, which compares favorably to that of other available split fluorescent protein-based probes. Successful visualization of interaction of two known protein partners in a living mouse model suggests iSplit as the probe of choice for noninvasive detection of protein-protein interactions in vivo, whereas its fast intracellular degradation enables time-resolved monitoring of repetitive binding events. PMID:23891149

  8. The Stellar Populations of Deeply Embedded Young Clusters: Near-Infrared Spectroscopy and Emergent Mass Distributions

    NASA Astrophysics Data System (ADS)

    Meyer, Michael R.

    1996-04-01

    The goal of this thesis is to test the following hypothesis: the initial distribution of stellar masses from a single "episode" of star formation is independent of the local physical conditions of the region. In other words, is the initial mass function (IMF) strictly universal over spatial scales d < 1 \\ pc and over time intervals Delta-tau << 3 x 10^6 yrs? We discuss the utility of embedded clusters in addressing this question. Using a combination of spectroscopic and photometric techniques, we seek to characterize emergent mass distributions of embedded clusters in order to compare them both with each other and with the field star IMF. Medium resolution (R=1000) near-infrared spectra obtainable with the current generation of NIR grating spectrographs can provide estimates of the photospheric temperatures of optically-invisible stars. Deriving these spectral types requires a three--step process; i) setting up a classification scheme based on near-infrared spectra of spectral standards; ii) understanding the effects of accretion on this classification scheme by studying optically-visible young stellar objects; and iii) applying this classification technique to the deeply embedded clusters. Combining near-infrared photometry with spectral types, accurate stellar luminosities can be derived for heavily reddened young stars thus enabling their placement in the H-R diagram. From their position in the H-R diagram, masses and ages of stars can be estimated from comparison with theoretical pre-main sequence evolutionary models. Because it is not practical to obtain complete spectroscopic samples of embedded cluster members, a technique is developed based solely on near-IR photometry for estimating stellar luminosities from flux--limited surveys. We then describe how spectroscopic surveys of deeply embedded clusters are necessary in order to adopt appropriate mass-luminosity relationships. Stellar luminosity functions constructed from complete extinction-limited samples

  9. Stellar Populations of Deeply Embedded Young Clusters: Near--Infrared Spectroscopy and Emergent Mass Distributions

    NASA Astrophysics Data System (ADS)

    Meyer, Michael R.

    1996-02-01

    The goal of this thesis is to test the following hypothesis: the initial distribution of stellar masses from a single ``episode'' of star formation is independent of the local physical conditions of the region. In other words, is the initial mass function (IMF) strictly universal over spatial scales d < 1 pc and over time intervals Δ τ << 3 × 106yrs? We discuss the utility of embedded clusters in addressing this question. Using a combination of spectroscopic and photometric techniques, we seek to characterize emergent mass distributions of embedded clusters in order to compare them both with each other and with the field star IMF. Medium resolution (R = 1000) near--infrared spectra obtainable with the current generation of NIR grating spectrographs can provide estimates of the photospheric temperatures of optically--invisible stars. Deriving these spectral types requires a three--step process; i) setting up a classification scheme based on near--infrared spectra of spectral standards; ii) understanding the effects of accretion on this classification scheme by studying optically--visible young stellar objects; and iii) applying this classification technique to the deeply embedded clusters. Combining near--infrared photometry with spectral types, accurate stellar luminosities can be derived for heavily reddened young stars thus enabling their placement in the H--R diagram. From their position in the H--R diagram, masses and ages of stars can be estimated from comparison with theoretical pre--main sequence evolutionary models. Because it is not practical to obtain complete spectroscopic samples of embedded cluster members, a technique is developed based solely on near--IR photometry for estimating stellar luminosities from flux--limited surveys. We then describe how spectroscopic surveys of deeply embedded clusters are necessary in order to adopt appropriate mass--luminosity relationships. Stellar luminosity functions constructed from complete extinction

  10. Near-infrared Imaging Polarimetry of GGD 27: Circular Polarization and Magnetic Field Structures

    NASA Astrophysics Data System (ADS)

    Kwon, Jungmi; Tamura, Motohide; Hough, James H.; Nagata, Tetsuya; Kusakabe, Nobuhiko; Saito, Hiro

    2016-06-01

    Near-infrared imaging polarimetry in the J, H, and K s bands was carried out for GGD 27 in the dark cloud Lynds 291. Details of an infrared reflection nebula associated with the optical nebulosity GGD 27 and the infrared nebula GGD 27 IRS are presented. Aperture photometry of 1263 point-like sources, detected in all three bands, was used to classify them based on a color-color diagram, and the linear polarization of several hundred sources was determined, with the latter used to map the magnetic field structure around GGD 27. This field, around GGD 27 IRS, appears to be associated with the extended CO outflow of IRAS 18162-2048 however, there are partly distorted or bent components in the field. The Chandrasekhar-Fermi method gives an estimate of the magnetic field strength as ˜90 μG. A region associated with GGD 27 IRS is discovered to have a circular polarization in the range of ˜2%-11% in the K s band. The circular polarization has an asymmetric positive/negative pattern and extends out to ˜ 120″ or 1.0 pc. The circular and linear polarization patterns are explained as resulting from a combination of dense inner and fainter outer lobes, suggesting episodic outflow.

  11. Near infrared photometric and optical spectroscopic study of 22 low mass star clusters embedded in nebulae

    NASA Astrophysics Data System (ADS)

    Soares, J. B.; Bica, E.; Ahumada, A. V.; Clariá, J. J.

    2008-02-01

    Aims:Among the star clusters in the Galaxy, those embedded in nebulae represent the youngest group, which has only recently been explored. The analysis of a sample of 22 candidate embedded stellar systems in reflection nebulae and/or HII environments is presented. Methods: We employed optical spectroscopic observations of stars in the directions of the clusters carried out at CASLEO (Argentina) together with near infrared photometry from the 2MASS catalogue. Our analysis is based on source surface density, colour-colour diagrams and on theoretical pre-main sequence isochrones. We take into account the field star contamination by carrying out a statistical subtraction. Results: The studied objects have the characteristics of low mass systems. We derive their fundamental parameters. Most of the cluster ages are younger than 2 Myr. The studied embedded stellar systems in reflection nebulae and/or HII region complexes do not have stars of spectral types earlier than B. The total stellar masses locked in the clusters are in the range 20-220 M⊙. They are found to be gravitationally unstable and are expected to dissolve in a timescale of a few Myr. Based on observations made at Complejo Astronómico El Leoncito, which is operated under agreement between the Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina and the National Universities of La Plata, Córdoba and San Juan, Argentina.

  12. NIMBUS: the Near-infrared Multi-Band Ultraprecise Spectroimager for SOFIA

    NASA Astrophysics Data System (ADS)

    McElwain, Michael W.; Mandell, Avi; Woodgate, Bruce; Spiegel, David S.; Madhusudhan, Nikku; Amatucci, Edward; Blake, Cullen; Budinoff, Jason; Burgasser, Adam; Burrows, Adam; Clampin, Mark; Conroy, Charlie; Deming, L. Drake; Dunham, Edward; Foltz, Roger; Gong, Qian; Knutson, Heather; Muench, Theodore; Murray-Clay, Ruth; Peabody, Hume; Rauscher, Bernard; Rinehart, Stephen; Villanueva, Geronimo

    2012-09-01

    We present a new and innovative near-infrared multi-band ultraprecise spectroimager (NIMBUS) for SOFIA. This design is capable of characterizing a large sample of extrasolar planet atmospheres by measuring elemental and molecular abundances during primary transit and occultation. This wide-field spectroimager would also provide new insights into Trans-Neptunian Objects (TNO), Solar System occultations, brown dwarf atmospheres, carbon chemistry in globular clusters, chemical gradients in nearby galaxies, and galaxy photometric redshifts. NIMBUS would be the premier ultraprecise spectroimager by taking advantage of the SOFIA observatory and state of the art infrared technologies. This optical design splits the beam into eight separate spectral bandpasses, centered around key molecular bands from 1 to 4μm. Each spectral channel has a wide field of view for simultaneous observations of a reference star that can decorrelate time-variable atmospheric and optical assembly effects, allowing the instrument to achieve ultraprecise calibration for imaging and photometry for a wide variety of astrophysical sources. NIMBUS produces the same data products as a low-resolution integral field spectrograph over a large spectral bandpass, but this design obviates many of the problems that preclude high-precision measurements with traditional slit and integral field spectrographs. This instrument concept is currently not funded for development.

  13. Astronomical photometry

    NASA Astrophysics Data System (ADS)

    Henden, Arne A.; Kaitchuck, Ronald H.

    A handbook of astronomical photometry is presented in a format amenable to both professional and amateur use. The fundamental equipment, procedures, theory, and applications of photometry are described. Photometric systems such as the UBV, M-K, and Stromgren classification methods are explained, together with statistical treatments of photometric data. Data reduction techniques and applications in air-mass calculations, the determination of first-order extinction, and for computing zero-point values are defined. Baseline standards such as solar, universal,and sidereal time, and dating methods are provided. Instructions for constructing photometer heads are given, and the operational principles and techniques for using pulse-counting and dc electronics are explored. Finally, observational techniques and applications of photoelectric photometry are suggested and targets are indicated. A review is also offered of the theoretical basis and computational tools involved in the science of astronomical photometry.

  14. Labeling and tracking of human mesenchymal stem cells using near-infrared technology.

    PubMed

    Armentero, Marie-Therese; Bossolasco, Patrizia; Cova, Lidia

    2013-01-01

    The recently developed near-infrared (NIR) light imaging technology combines low background noise with deep tissue penetration and readily allows imaging and tracking of NIR-labeled cells, following transplantation in small animal model of diseases. The real-time and longitudinal detection of grafted cells in vivo, as well as their rapid ex vivo localization, may further clarify graft interactions with the surrounding, in target and nontarget organs throughout the body, over time. The present chapter describes a protocol for (1) the efficient labeling of human mesenchymal stem cells (hMSCs) using a membrane intercalating dye, emitting in the NIR 815 nm spectrum; (2) the stereotaxic transplantation of NIR 815-hMSCs in rodent model of Parkinson's disease; and (3) the longitudinal in vivo detection of the grafted cells and the subsequent ex vivo imaging in selected tissues.

  15. Hemodynamic correlates of visuomotor motor adaptation by functional Near Infrared Spectroscopy.

    PubMed

    Gentili, Rodolphe J; Hadavi, Cyrus; Ayaz, Hasan; Shewokis, Patricia A; Contreras-Vidal, Jose L

    2010-01-01

    The development of rehabilitation engineering technologies such as the design of smart prosthetics necessitates a deep understanding of brain mechanisms engaged in ecological situations when human interact with new tools and/or environments. Thus, we aimed to investigate potential hemodynamic signatures reflecting the level of cognitive-motor performance and/or the internal or mental states of individuals when learning a novel tool with unknown properties. These markers were derived from functional Near Infrared Spectroscopy (fNIR) signals. Our results indicate an increased level of oxy-hemoglobin in prefrontal sensors associated with enhanced kinematics during early compared with late learning. This is consistent with previous neuroimaging studies that revealed a higher contribution of prefrontal areas during early compare to late adaptation learning. These non-invasive functional hemodynamic markers may play a role in bioengineering applications such as smart neuroprosthesis and brain monitoring where adaptive behavior is important.

  16. Multispectral imaging in the extended near-infrared window based on endogenous chromophores

    PubMed Central

    Cao, Qian; Zhegalova, Natalia G.; Wang, Steven T.; Akers, Walter J.

    2013-01-01

    Abstract. To minimize the problem with scattering in deep tissues while increasing the penetration depth, we explored the feasibility of imaging in the relatively unexplored extended near infrared (exNIR) spectral region at 900 to 1400 nm with endogenous chromophores. This region, also known as the second NIR window, is weakly dominated by absorption from water and lipids and is free from other endogenous chromophores with virtually no autofluorescence. To demonstrate the applicability of the exNIR for bioimaging, we analyzed the optical properties of individual components and biological tissues using an InGaAs spectrophotometer and a multispectral InGaAs scanning imager featuring transmission geometry. Based on the differences in spectral properties of tissues, we utilized ratiometric approaches to extract spectral characteristics from the acquired three-dimensional “datacube”. The obtained images of an exNIR transmission through a mouse head revealed sufficient details consistent with anatomical structures. PMID:23933967

  17. Observing Resolved Stellar Populations with the JWST Near-Infrared Spectrograph

    NASA Astrophysics Data System (ADS)

    Gilbert, K. M.; Beck, T. L.; Karakla, D. M.

    2016-10-01

    The James Webb Space Telescope's (JWST) Near Infrared Spectrograph (NIRSpec) will provide a multi-object spectroscopy (MOS) mode through the Micro-Shutter Array (MSA). Each MSA quadrant is a grid of contiguous shutters that can be configured to form slits on more than 100 astronomical targets simultaneously. The combination of JWST's sensitivity and superb resolution in the infrared and NIRSpec's full wavelength coverage over 0.6 to 5 μm will open new parameter space for studies of galaxies and resolved stellar populations alike. We describe a NIRSpec MSA observing scenario of spectroscopy of individual stars in an external galaxy, and investigate the technical challenges posed by this scenario. This use case and others, including a deep galaxy survey and observations of Galactic HII regions, are guiding development of the NIRSpec user interfaces including proposal planning and pipeline calibrations.

  18. Gemini near-infrared observations of Europa's Hydrated Surface Materials

    NASA Astrophysics Data System (ADS)

    Tsang, C.; Spencer, J. R.; Grundy, W. M.; Dalton, J. B.

    2012-12-01

    Europa is a highly dynamic icy moon of Jupiter. It is thought the moon harbors a subsurface ocean, with the potential to sustain life, with Europa being a key target of ESA's forthcoming Jupiter Icy Moons Orbiter (JUICE) mission. However, much is not known concerning the chemistry of the subsurface ocean. The surface is dominated by water ice, with a hydrated non-ice material component providing the distinctive albedo contrasts seen at visible and near-infrared wavelengths. These non-ice materials are concentrated at disrupted surface regions, providing a diagnostic probe for the chemistry and characteristics of the liquid ocean beneath. Leading but potentially competing theories on the composition of these hydrated non-ice materials suggest either sulfuric acid-water mixtures (Carlson et al., 1999) or hydrated magnesium/sodium salts (McCord et al., 1999). Recent reanalysis of Galileo-NIMS observations suggest a mixture of both - hydrated salts are present at all longitudes but the sulfuric acid hydrates are localized on the trailing side. We present preliminary analysis of new ground-based Gemini disk-resolved spectroscopy of Europa using the Near-Infrared Integrated Field Spectrometer (NIFS), taken in late 2011, at H (1.49 - 1.80 μm) and K bands (1.99 - 2.40 μm) with spectral resolving powers of ~ 5300. At these NIR wavelengths, with spectral resolution much better than Galileo-NIMS, the spectral absorption and continuum characteristics of these ice and non-ice materials can be separated out. In addition, the spatial resolution potentially allows identification of localized materials whose signature would be diluted in disk-integrated spectra. These observations of the trailing hemisphere use Altair adaptive optics to achieve spatial resolutions of 0.1" (~310 km per pixel) or better, potentially leading to better identification of the non-ice materials and their spatial distributions. References Carlson, R.W., R.E. Johnson, and M.S. Anderson 1999. Sulfuric acid

  19. Near-infrared studies of embedded star clusters

    NASA Astrophysics Data System (ADS)

    Park, Chan

    The Fan Mountain Near-Infrared Camera, FanCam, features an 8.7'x8.7' field of view on a 1024x1024 Teledyne Imaging Sensors HAWAII-1 detector array. The instrument mounts at the f/15.5 focus of the 31 inch telescope. Its seeing-limited optical design, optimized for the JHK atmospheric bands, includes a field stop at the telescope focus, a doublet collimator, two 8-position filterwheels straddling a Lyot stop, and a doublet reimager. The 0.51''pixel-1 plate scale leads to a slightly oversampled point spread function for the typical seeing of 1.5''. The entire optical train is encased in a cryogenic dewar cooled by a closed-loop cooling system. Chapter 2 describes the camera design and some early results of camera performance test. Long term near-infrared, J, H, and Ks, photometric monitoring of the embedded cluster NGC 1333 is presented in Chapter 3. We employ the Stetson variability index and reduced chi 2 to identify variable objects. Color-magnitude and color-color diagrams demonstrate that NGC 1333 is extremely young and highly extincted. Light curves in all three bands are well correlated. The spatial distribution of variable stars shows a strong correlation with the peak of the extinction map while non-variable stars are evenly spread over the whole field of view. Spitzer-2MASS-identified IR excess YSOs and Chandra X-ray sources were compared with our variable stars. A total of 25 previously-unknown member candidates are presented, with 15 objects in the mass range of brown dwarfs. The IMF and mass distribution of the cluster are presented. We discuss the implication of Ks vs. H--Ks color-magnitude diagram slope statistics in view of the evolutionary sequence of young star-forming embedded clusters. Another long term near-infrared, J, H, and Ks, photometric monitoring performed with FanCam for the embedded cluster NGC 7129 is presented in Chapter 4.

  20. Effect of valsalva maneuver-induced hemodynamic changes on brain near-infrared spectroscopy measurements.

    PubMed

    Tsubaki, Atsuhiro; Kojima, Sho; Furusawa, Adriane Akemi; Onishi, Hideaki

    2013-01-01

    Near-infrared spectroscopy (NIRS) is widely used to measure human brain activation on the basis of cerebral hemodynamic response. However, a limitation of NIRS is that systemic changes influence the measured signals. The purpose of this study was to clarify the relationship between NIRS signals and blood pressure during the Valsalva maneuver. Nine healthy volunteers performed a 20-s Valsalva maneuver to change their blood pressure. Changes in oxyhemoglobin (O2Hb) concentration were measured with 34 channels with an inter-optode distance of 30 mm for deep-penetration measurements (deepO2Hb) and 9 channels with an inter-optode distance of 15 mm for shallow-penetration measurements (shallowO2Hb). The difference value (diffO2Hb) between deepO2Hb and shallowO2Hb was calculated. Mean arterial pressure (MAP) was recorded by volume clamping the finger pulse, and skin blood flow changes were measured at the forehead. Pearson's correlation coefficients between deepO2Hb and MAP, shallowO2Hb and MAP, and diffO2Hb and MAP were 0.893 (P < 0.01), 0.963 (P < 0.01), and 0.831 (P < 0.01), respectively. The results suggest that regional and systemic changes in the cardiovascular state strongly influence NIRS signals.

  1. Combining near-infrared illuminants to optimize venous imaging

    NASA Astrophysics Data System (ADS)

    Paquit, Vincent; Price, Jeffery R.; Mériaudeau, Fabrice; Tobin, Kenneth W., Jr.; Ferrell, Thomas L.

    2007-03-01

    The first and perhaps most important phase of a surgical procedure is the insertion of an intravenous (IV) catheter. Currently, this is performed manually by trained personnel. In some visions of future operating rooms, however, this process is to be replaced by an automated system. We previously presented work for localizing near-surface veins via near-infrared (NIR) imaging in combination with structured light ranging for surface mapping and robotic guidance. In this paper, we describe experiments to determine the best NIR wavelengths to optimize vein contrast for physiological differences such as skin tone and/or the presence of hair on the arm or wrist surface. For illumination, we employ an array of NIR LEDs comprising six different wavelength centers from 740nm to 910nm. We capture imagery of each subject under every possible combination of illuminants and determine the optimal combination of wavelengths for a given subject to maximize vein contrast using linear discriminant analysis.

  2. Study of surfaces using near infrared optical fiber spectrometry

    NASA Technical Reports Server (NTRS)

    Workman, G. L.; Arendale, W. A.; Hughes, C.

    1995-01-01

    The measurement and control of cleanliness for critical surfaces during manufacturing and in service provides a unique challenge for fulfillment of environmentally benign operations. Of particular interest has been work performed in maintaining quality in the production of bondline surfaces in propulsion systems and the identification of possible contaminants. This work requires an in-depth study of the possible sources of contamination, methodologies to identify contaminants, discrimination between contaminants and chemical species caused by environment, and the effect of particular contaminants on the bondline integrity of the critical surfaces. This presentation will provide an introduction to the use of optical fiber spectrometry in a nondestructive measurement system for process monitoring and how it can be used to help clarify issues concerning surface chemistry. Correlation of the Near Infrared (NIR) spectroscopic results with Optical Stimulated Electron Emission (OSEE) and ellipsometry will also be presented.

  3. Intravascular near-infrared fluorescence molecular imaging of atherosclerosis

    PubMed Central

    Thukkani, Arun K; Jaffer, Farouc A

    2013-01-01

    Novel imaging modalities are required to better identify vulnerable atherosclerotic plaques before their dire consequences of myocardial infarction, sudden death, and stroke. Moving beyond traditional diagnostic methods, the field of molecular imaging offers an innovative approach to report upon critical in vivo biological features of high-risk plaques. Molecular imaging employs engineered, targeted imaging agents in conjunction with sophisticated, high-resolution detection systems. While various modalities have been investigated for this purpose, intravascular near infrared fluorescence imaging (NIRF) strategies are uniquely poised to provide high-resolution readouts of human coronary artery plaques. To date, preclinical animal studies have demonstrated feasibility of both standalone NIRF intravascular imaging as well as dual-modality approaches detecting inflammation and fibrin deposition in coronary-sized arteries. This translatable catheter-based approach is positioned to advance the identification of biologically vulnerable coronary plaques and coronary stents at risk of thrombosis. PMID:23638334

  4. Near-infrared observations of the variable crab nebula

    NASA Astrophysics Data System (ADS)

    Yamamoto, M.; Mori, K.; Shibata, S.; Tsujimoto, M.; Misawa, T.; Burrows, D.; Kawai, N.

    We present three near-infrared NIR observations of the Crab Nebula obtained with CISCO on the Subaru Telescope and Quick Infrared Camera on the University of HAWAII 88 inch Telescope The observations were performed on 2004 September 2005 February and 2005 October and were coordinated with X-ray observations obtained with the Chandra X-ray observatory within 10 days As shown in previous optical and X-ray monitoring observations outward-moving wisps and variable knots are detected also in our NIR observations The NIR variations are closely correlated with variations in the X-ray observations indicating that both variations are driven by the same physical process We discuss the origin of NIR-emitting particles based on the temporal variations as well as the spectral energy distributions of each variable component

  5. Extended near infrared emission from visual reflection nebulae

    NASA Technical Reports Server (NTRS)

    Sellgren, K.; Werner, M. W.; Dinerstein, H. L.

    1982-01-01

    Extended near infrared (2 to 5 microns) emission was observed from three visual reflection nebulae, NGC 7023, 2023, and 2068. The emission from each nebula consists of a smooth continuum, which can be described by a greybody with a color temperature of 1000 K, and emission features at 3.3 and 3.4 microns. The continuum emission cannot be explained by free-free emission, reflected light, or field stars, or by thermal emission from grains, with commonly accepted ratios of infrared to ultraviolet emissivities, which are in equilibrium with the stellar radiation field. A possible explanation is thermal emission from grains with extremely low ratios of infrared to ultraviolet emissivities, or from grains with a temperature determined by mechanisms other than equilibrium radiative heating. Another possibility is continuum fluorescence.

  6. Functional Near Infrared Spectroscopy: Watching the Brain in Flight

    NASA Technical Reports Server (NTRS)

    Harrivel, Angela; Hearn, Tristan A.

    2012-01-01

    Functional Near Infrared Spectroscopy (fNIRS) is an emerging neurological sensing technique applicable to optimizing human performance in transportation operations, such as commercial aviation. Cognitive state can be determined via pattern classification of functional activations measured with fNIRS. Operational application calls for further development of algorithms and filters for dynamic artifact removal. The concept of using the frequency domain phase shift signal to tune a Kalman filter is introduced to improve the quality of fNIRS signals in real-time. Hemoglobin concentration and phase shift traces were simulated for four different types of motion artifact to demonstrate the filter. Unwanted signal was reduced by at least 43%, and the contrast of the filtered oxygenated hemoglobin signal was increased by more than 100% overall. This filtering method is a good candidate for qualifying fNIRS signals in real time without auxiliary sensors.

  7. Functional Near Infrared Spectroscopy: Watching the Brain in Flight

    NASA Technical Reports Server (NTRS)

    Harrivel, Angela; Hearn, Tristan

    2012-01-01

    Functional Near Infrared Spectroscopy (fNIRS) is an emerging neurological sensing technique applicable to optimizing human performance in transportation operations, such as commercial aviation. Cognitive state can be determined via pattern classification of functional activations measured with fNIRS. Operational application calls for further development of algorithms and filters for dynamic artifact removal. The concept of using the frequency domain phase shift signal to tune a Kalman filter is introduced to improve the quality of fNIRS signals in realtime. Hemoglobin concentration and phase shift traces were simulated for four different types of motion artifact to demonstrate the filter. Unwanted signal was reduced by at least 43%, and the contrast of the filtered oxygenated hemoglobin signal was increased by more than 100% overall. This filtering method is a good candidate for qualifying fNIRS signals in real time without auxiliary sensors

  8. Characteristic wavelength of textile fiber in near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Feng, Hongnian; Jin, Shangzhong; Gan, Bin

    2006-01-01

    Near Infrared (NIR) spectroscopy in the region from 1300 to 1700nm, coupled with multivariate analytic statistical techniques, have been used to predict the chemical properties of textile fiber. Molecule absorbs electromagnetic wave with especial wavelength, which leads to bring characteristic absorption spectrum. Characteristic wavelength is the most important parameter in NIR detection. How to select characteristic wavelength is the key to NIR measure. Different mathematical methods are used to find relationship between the NIR absorption spectrum and the chemical properties of the textile fiber. We adopt stepwise multiple linear regression (SMLR) to select characteristic wavelength. As objective condition is limited, this article only refers to cotton and terylene. By computing correlation coefficient, we establish calibration equation with the smoothed absorbance data. Finally, the bias was controlled under 6%. Then, we find that NIR can be used to carry on qualitative analysis and quantitative analysis of the textile.

  9. Detecting counterfeit antimalarial tablets by near-infrared spectroscopy.

    PubMed

    Dowell, Floyd E; Maghirang, Elizabeth B; Fernandez, Facundo M; Newton, Paul N; Green, Michael D

    2008-11-04

    Counterfeit antimalarial drugs are found in many developing countries, but it is challenging to differentiate between genuine and fakes due to their increasing sophistication. Near-infrared spectroscopy (NIRS) is a powerful tool in pharmaceutical forensics, and we tested this technique for discriminating between counterfeit and genuine artesunate antimalarial tablets. Using NIRS, we found that artesunate tablets could be identified as genuine or counterfeit with high accuracy. Multivariate classification models indicated that this discriminatory ability was based, at least partly, on the presence or absence of spectral signatures related to artesunate. This technique can be field-portable and requires little training after calibrations are developed, thus showing great promise for rapid and accurate fake detection.

  10. Near Infrared Excess Energy in Binary System V367 Cygni

    NASA Astrophysics Data System (ADS)

    Gunasekera, Saraj

    Spectral energy distribution of the Serpentid type binary V367 Cyg was obtained using several previous photometric measurements made on this system in different spectral bands. We found Near IR excess starting from 3μm and this excess flux is attributed to the free-free emission from the mass accretion disk of the binary system. We adopted the temperature of primary component as 8,000°K. We added the free-free emission flux of the circumstellar disk to the black body energy of the primary component to find a best fit for the observed near infrared excess flux. In this fitting we left the electron density of the circumstellar disk ne of the free-free emission as a free parameter. We found that volume emission measure of the circumstellar disk is ˜ 9 × 1059 cm-3.

  11. Near-infrared Spectroscopy in the Brewing Industry.

    PubMed

    Sileoni, Valeria; Marconi, Ombretta; Perretti, Giuseppe

    2015-01-01

    This article offers an exhaustive description of the use of Near-Infrared (NIR) Spectroscopy in the brewing industry. This technique is widely used for quality control testing of raw materials, intermediates, and finished products, as well as process monitoring during malting and brewing. In particular, most of the reviewed works focus on the assessment of barley properties, aimed at quickly selecting the best barley varieties in order to produce a high-quality malt leading to high-quality beer. Various works concerning the use of NIR in the evaluation of raw materials, such as barley, malt, hop, and yeast, are also summarized here. The implementation of NIR sensors for the control of malting and brewing processes is also highlighted, as well as the use of NIR for quality assessment of the final product.

  12. Aquaphotomics: Near Infrared Spectroscopy and Water States in Biological Systems.

    PubMed

    Tsenkova, Roumiana; Kovacs, Zoltan; Kubota, Yosuke

    2015-01-01

    Aquaphotomics is a new discipline that provides a framework for understanding changes in water molecular system presented as a water spectral pattern, to mirror the rest of the solution and to give a holistic description related to system functionality. One of its main purposes is to identify water bands as main coordinates of future absorbance patterns to be used as a system biomarker. This chapter presents the Aquaphotomics methodology and illustrates a way to identify specific water bands using temperature change and addition of solutions of different ionic strength as perturbations. Rapid and precise measurement of low concentration solutes has been given as a strong evidence of the vast information that "the water spectral pattern as molecular mirror" approach provides. Few applications using near infrared spectroscopy and multivariate analysis as main tools of Aquaphotomics have been presented.

  13. Transmission spectra of teeth in the visible to near infrared

    NASA Astrophysics Data System (ADS)

    Herr, Steven L.; Harbour, John D.; Sherwood, Timothy S.; Wist, Abund O.

    1994-05-01

    Investigations of new transillumination techniques have created a need for detailed transmission studies of teeth and tissues. Recent results have shown that light imaging of extracted teeth can identify small (1 mm2 cross-section) caries in teeth by raster scanning using helium-neon laser light and a post collimated in-line detector. Preliminary frequency (wavelength) dependent transmission studies have been carried out from the visible to the near infrared spectral regions on the dentin of a slice of an extracted tooth 1.85 mm thick. These preliminary results show that in the region from 5,000 to 20,000 cm-1 the dentin of an extracted, healthy, human tooth has a transmission of between 2.5 and 5.5 percent, indicating that the total attenuation coefficient is between 16 and 19.5 cm-1.

  14. Analysis of silage composition by near-infrared reflectance spectroscopy

    NASA Astrophysics Data System (ADS)

    Reeves, James B., III; Blosser, Timothy H.; Colenbrander, V. F.

    1991-02-01

    Two studies were performed to investigate the feasibility of using near infrared reflectance spectroscopy (NIRS) with undried silages. In the first study silages were analyzed for major components (e. g. dry matter crude protein and other forms of nitrogen fiber and in vitro digestible dry matter) and short chain fatty acids (SCFA). NIRS was found to operate satisfactorily except for some forms of nitrogen and SCFA. In study two various methods of grinding spectral regions and sample presentation were examined. Undried Wiley ground samples in a rectangular cell gave the best overall results for non-dry ice undried grinds with wavelengths between 1100 and 2498 nm. Silages scanned after drying however produced the best results. Intact samples did not perform as well as ground samples and wavelengths below 1100 nm were of little use. 2 .

  15. Near infrared reflectance measurement of nitrogen faecal losses.

    PubMed

    Benini, L; Caliari, S; Bonfante, F; Guidi, G C; Brentegani, M T; Castellani, G; Sembenini, C; Bardelli, E; Vantini, I

    1992-06-01

    Chemical methods of measuring nitrogen in stools are complex, unpleasant, and therefore rarely performed. Recently, near infrared reflectance (NIRA) has been suggested for stool analysis. The aim of this study was to evaluate the possible application of this method in routine faecal nitrogen measurement. Nitrogen concentration and daily output were measured in the stools of 83 patients using NIRA and, for comparison, the Kjeldahl method. Nitrogen concentration and output ranged between 0.4-2.72 g% and 0.45-8.96 g/day respectively. Correlation coefficients (r), of 0.89 and 0.97 were found between the two methods for concentration and output respectively, and similar values were found in patients on enteral nutrition. Repeated measurements from the same stool collection, requiring only a few minutes, allowed homogenisation to be avoided. NIRA seems to be an easy, fast, and reliable alternative to chemical assays of nitrogen measurement in the management of patients with digestive disorders.

  16. Near-infrared Molecular Probes for In Vivo Imaging

    PubMed Central

    Zhang, Xuan; Bloch, Sharon; Akers, Walter; Achilefu, Samuel

    2012-01-01

    Cellular and tissue imaging in the near-infrared (NIR) wavelengths between 700 and 900 nm is advantageous for in vivo because of the low absorption of biological molecules in this region. This Unit presents protocols for small animal imaging using planar and fluorescence lifetime imaging techniques. Included is an overview of NIR fluorescence imaging of cells and small animals using NIR organic fluorophores, nanoparticles, and multimodal imaging probes. The development, advantages, and application of NIR fluorescent probes that have been used for in vivo imaging are also summarized. The use of NIR agents in conjunction with visible dyes and considerations in selecting imaging agents are discussed. We conclude with practical considerations for the use of these dyes in cell and small animal imaging applications. PMID:22470154

  17. Visible and near infrared reflectances measured from laboratory ice clouds.

    PubMed

    Barkey, Brian; Liou, K N

    2008-05-01

    We present laboratory results of the 0.68 microm visible (VIS) and 1.617 microm near infrared (NIR) reflectances typically used for inferring optical depth and ice crystal size from satellite radiometers, from ice clouds generated in a temperature controlled column cloud chamber. Two types of ice crystals were produced in this experiment: small columns and dendrites with mean maximum dimensions of about 17 and 35 microm. Within experimental uncertainty, the measured reflectances from ice clouds at both wavelengths agree reasonably well with the theoretical results computed from the plane-parallel adding-doubling method for radiative transfer using the measured ice particle morphology. We demonstrate that laboratory scattering and reflectance data for thin ice clouds with optical depths less than 0.4 can be used for validation of the thin cirrus optical depth and ice crystal size that have been routinely retrieved from the satellite VIS-NIR two channel pair.

  18. Near Infrared Fluorescent NanoGUMBOS for Biomedical Imaging

    PubMed Central

    Bwambok, David K.; El-Zahab, Bilal; Challa, Santhosh K.; Li, Min; Chandler, Lin; Baker, Gary A.; Warner, Isiah M.

    2009-01-01

    Herein, we report on near infrared (NIR) fluorescent nanoparticles generated from an emergent class of materials we refer to as a Group of Uniform Materials Based on Organic Salts (GUMBOS). GUMBOS are largely frozen ionic liquids, although the concept is more general and is also easily applied to solid ionic materials with melting points in excess of 100 °C. Nanoparticles based on GUMBOS (nanoGUMBOS) derived from a NIR fluorophore are prepared using a reprecipitation method and evaluated for in vivo fluorescence imaging. Due to their uniformity, single-step preparation, and composite nature, nanoGUMBOS help to resolve issues with dye leakage problems innate to alternate cellular stains and unlock a myriad of applications for these materials, highlighting exciting possibilities for multifunctional nanoGUMBOS. PMID:19928781

  19. Design of planar chiral metamaterials for near-infrared regime

    NASA Astrophysics Data System (ADS)

    Kaya, Sabri; Turkmen, Mustafa; Topaktas, Omer

    2017-01-01

    Planar chiral metamaterials (PCMs) comprising double-layer dielectric-metal-dielectric resonant structures in the shape of a windmill are presented for near-infrared regime. The circular dichroism is retrieved from transmission spectra. Effects of used materials on circular dichroism characteristics of PCM arrays are investigated for the first time. The dependence of spectral characteristics on the geometrical parameters of the PCMs is analyzed by the finite-difference time-domain method. The observations indicated that the circular dichroism characteristics of the proposed PCM arrays are strongly dependent on the type of metal and dielectric materials. Due to the enhanced chiroptical near-field response and tunable spectral behavior, proposed PCM arrays may have potential for biosensing applications of chiral biomolecules.

  20. Non-invasive neuroimaging using near-infrared light

    NASA Technical Reports Server (NTRS)

    Strangman, Gary; Boas, David A.; Sutton, Jeffrey P.

    2002-01-01

    This article reviews diffuse optical brain imaging, a technique that employs near-infrared light to non-invasively probe the brain for changes in parameters relating to brain function. We describe the general methodology, including types of measurements and instrumentation (including the tradeoffs inherent in the various instrument components), and the basic theory required to interpret the recorded data. A brief review of diffuse optical applications is included, with an emphasis on research that has been done with psychiatric populations. Finally, we discuss some practical issues and limitations that are relevant when conducting diffuse optical experiments. We find that, while diffuse optics can provide substantial advantages to the psychiatric researcher relative to the alternative brain imaging methods, the method remains substantially underutilized in this field.

  1. Componential distribution analysis of food using near infrared ray image

    NASA Astrophysics Data System (ADS)

    Yamauchi, Hiroki; Kato, Kunihito; Yamamoto, Kazuhiko; Ogawa, Noriko; Ohba, Kimie

    2008-11-01

    The components of the food related to the "deliciousness" are usually evaluated by componential analysis. The component content and type of components in the food are determined by this analysis. However, componential analysis is not able to analyze measurements in detail, and the measurement is time consuming. We propose a method to measure the two-dimensional distribution of the component in food using a near infrared ray (IR) image. The advantage of our method is to be able to visualize the invisible components. Many components in food have characteristics such as absorption and reflection of light in the IR range. The component content is measured using subtraction between two wavelengths of near IR light. In this paper, we describe a method to measure the component of food using near IR image processing, and we show an application to visualize the saccharose in the pumpkin.

  2. Combining near-infrared illuminants to optimize venous imaging

    SciTech Connect

    Paquit, Vincent C; Price, Jeffery R; Meriaudeau, Fabrice; Tobin Jr, Kenneth William; Ferrell, Thomas L

    2007-01-01

    The first and perhaps most important phase of a surgical procedure is the insertion of an intravenous (IV) catheter. Currently, this is performed manually by trained personnel. In some visions of future operating rooms, however, this process is to be replaced by an automated system. We previously presented work for localizing near-surface veins via near-infrared (NIR) imaging in combination with structured light ranging for surface mapping and robotic guidance. In this paper, we describe experiments to determine the best NIR wavelengths to optimize vein contrast for physiological differences such as skin tone and/or the presence of hair on the arm or wrist surface. For illumination, we employ an array of NIR LEDs comprising six different wavelength centers from 740nm to 910nm. We capture imagery of each subject under every possible combination of illuminants and determine the optimal combination of wavelengths for a given subject to maximize vein contrast using linear discriminant analysis.

  3. Discrimination and content analysis of fritillaria using near infrared spectroscopy.

    PubMed

    Meng, Yu; Wang, Shisheng; Cai, Rui; Jiang, Bohai; Zhao, Weijie

    2015-01-01

    Fritillaria is a traditional Chinese herbal medicine which can be used to moisten the lungs. The objective of this study is to develop simple, accurate, and solvent-free methods to discriminate and quantify Fritillaria herbs from seven different origins. Near infrared spectroscopy (NIRS) methods are established for the rapid discrimination of seven different Fritillaria samples and quantitative analysis of their total alkaloids. The scaling to first range method and the partial least square (PLS) method are used for the establishment of qualitative and quantitative analysis models. As a result of evaluation for the qualitative NIR model, the selectivity values between groups are always above 2, and the mistaken judgment rate of fifteen samples in prediction sets was zero. This means that the NIR model can be used to distinguish different species of Fritillaria herbs. The established quantitative NIR model can accurately predict the content of total alkaloids from Fritillaria samples.

  4. Tailored Near-Infrared Contrast Agents for Image Guided Surgery

    PubMed Central

    Njiojob, Costyl N.; Owens, Eric A.; Narayana, Lakshminarayana; Hyun, Hoon; Choi, Hak Soo; Henary, Maged

    2015-01-01

    The success of near-infrared (NIR) fluorescence to be employed for intraoperative imaging relies on the ability to develop a highly stable, NIR fluorescent, nontoxic, biocompatible, and highly excreted compound that retains a reactive functionality for conjugation to a cancer-recognizing peptide. Herein, systematic modifications to previously detailed fluorophore ZW800-1 are explored. Specific modifications, including the isosteric replacement of the O atom of ZW800-1, include nucleophilic amine and sulfur species attached to the heptamethine core. These novel compounds have shown similar satisfactory results in biodistribution and clearance while also expressing increased stability in serum. Most importantly, all of the synthesized and evaluated compounds display a reactive functionality (either a free amino group or carboxylic acid moiety) for further bioconjugation. The results obtained from the newly prepared derivatives demonstrate that the central substitution with the studied linking agents retains the ultralow background in vivo performance of the fluorophores regardless of the total net charge. PMID:25711712

  5. Canopy near-infrared reflectance and terrestrial photosynthesis

    PubMed Central

    Badgley, Grayson; Field, Christopher B.; Berry, Joseph A.

    2017-01-01

    Global estimates of terrestrial gross primary production (GPP) remain highly uncertain, despite decades of satellite measurements and intensive in situ monitoring. We report a new approach for quantifying the near-infrared reflectance of terrestrial vegetation (NIRV). NIRV provides a foundation for a new approach to estimate GPP that consistently untangles the confounding effects of background brightness, leaf area, and the distribution of photosynthetic capacity with depth in canopies using existing moderate spatial and spectral resolution satellite sensors. NIRV is strongly correlated with solar-induced chlorophyll fluorescence, a direct index of photons intercepted by chlorophyll, and with site-level and globally gridded estimates of GPP. NIRV makes it possible to use existing and future reflectance data as a starting point for accurately estimating GPP. PMID:28345046

  6. Near-infrared imaging of demineralization under sealants

    NASA Astrophysics Data System (ADS)

    Tom, Henry; Simon, Jacob C.; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2014-07-01

    Previous studies have shown that near-infrared (NIR) reflectance and transillumination imaging can be used to acquire high contrast images of early caries lesions and composite restorative materials. The aim of the study was to determine the optimum NIR wavelengths for imaging demineralized areas under dental sealants. Fifteen natural human premolars and molars with occlusal lesions were used in this in vitro study. Images before and after application of sealants were acquired using NIR reflectance and NIR transillumination at wavelengths of 1300, 1460, and 1500 to 1700 nm. Images were also acquired using polarization sensitive optical coherence tomography (OCT) for comparison. The highest contrast for NIR reflectance was at 1460 nm and 1500 to 1700 nm. These NIR wavelengths are coincident with higher water absorption. The clear Delton sealant investigated was not visible in either copolarization or cross-polarization OCT images. The wavelength region between 1500 and 1700 nm yielded the highest contrast of lesions under sealants for NIR reflectance measurements.

  7. Near infrared photodissociation spectra of the aniline +-argon ionic complexes

    NASA Astrophysics Data System (ADS)

    Pino, T.; Douin, S.; Boudin, N.; Bréchignac, Ph.

    2006-02-01

    The near infrared spectra of the ionic complexes aniline(NH 2) +-argon and aniline(ND 2) +-argon have been measured by laser photodissociation spectroscopy. The bands observed from 10 500 to 13 500 cm -1 have been assigned to the D1(A˜2A2)←D0(X˜2B1) electronic transition within the solvated chromophore. They are characterized by a long vibrational progression involving the 6a mode. On the basis of CASSCF calculations, a large change of geometry along this coordinate is found while the amino group remains in the ring plane. Therefore, a change of the conjugation of the ring rather than a charge transfer is inferred. This is thought to be the origin of the extent of the progression.

  8. Cardiac tissue characterization using near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Singh Moon, Rajinder; Hendon, Christine P.

    2014-03-01

    Cardiac tissue from swine and canine hearts were assessed using diffuse reflectance near-infrared spectroscopy (NIRS) ex vivo. Slope measured between 800-880 nm reflectance was found to reveal differences between epicardial fat and normal myocardium tissue. This parameter was observed to increase monotonically from measurements obtained from the onset of radiofrequency ablation (RFA). A sheathe-style fiber optic catheter was then developed to allow real-time sampling of the zone of resistive heating during RFA treatment. A model was developed and used to extract changes in tissue absorption and reduced scattering based on the steady-state diffusion approximation. It was found that key changes in tissue optical properties occur during application of RF energy and can be monitored using NIRS. These results encourage the development of NIRS integrated catheters for real-time guidance of the cardiac ablation treatment.

  9. A near-infrared survey of the entire R Coronae Australis cloud

    NASA Astrophysics Data System (ADS)

    Haas, M.; Heymann, F.; Domke, I.; Drass, H.; Chini, R.; Hoffmeister, V.

    2008-09-01

    an edge-on disc. Conclusions: The deep near-infrared survey of the entire R CrA molecular cloud strengthens the evidence for the Coronet being the region where most of the young stars are found. Our results are consistent with earlier predictions that the R CrA cloud has fragmented into sub-condensations at different star-forming stages. Table A1 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/488/987

  10. Engineering adenylate cyclases regulated by near-infrared window light.

    PubMed

    Ryu, Min-Hyung; Kang, In-Hye; Nelson, Mathew D; Jensen, Tricia M; Lyuksyutova, Anna I; Siltberg-Liberles, Jessica; Raizen, David M; Gomelsky, Mark

    2014-07-15

    Bacteriophytochromes sense light in the near-infrared window, the spectral region where absorption by mammalian tissues is minimal, and their chromophore, biliverdin IXα, is naturally present in animal cells. These properties make bacteriophytochromes particularly attractive for optogenetic applications. However, the lack of understanding of how light-induced conformational changes control output activities has hindered engineering of bacteriophytochrome-based optogenetic tools. Many bacteriophytochromes function as homodimeric enzymes, in which light-induced conformational changes are transferred via α-helical linkers to the rigid output domains. We hypothesized that heterologous output domains requiring homodimerization can be fused to the photosensory modules of bacteriophytochromes to generate light-activated fusions. Here, we tested this hypothesis by engineering adenylate cyclases regulated by light in the near-infrared spectral window using the photosensory module of the Rhodobacter sphaeroides bacteriophytochrome BphG1 and the adenylate cyclase domain from Nostoc sp. CyaB1. We engineered several light-activated fusion proteins that differed from each other by approximately one or two α-helical turns, suggesting that positioning of the output domains in the same phase of the helix is important for light-dependent activity. Extensive mutagenesis of one of these fusions resulted in an adenylate cyclase with a sixfold photodynamic range. Additional mutagenesis produced an enzyme with a more stable photoactivated state. When expressed in cholinergic neurons in Caenorhabditis elegans, the engineered adenylate cyclase affected worm behavior in a light-dependent manner. The insights derived from this study can be applied to the engineering of other homodimeric bacteriophytochromes, which will further expand the optogenetic toolset.

  11. Investigation of graphene applied on near infrared photodetector (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Lien, I.-Chun; Chen, Sheng-Hui

    2016-10-01

    The particular Graphene-Germanium-Graphene photodetector (GSG PD) is investigated in this research. Germanium has good absorption coefficient in near infrared such as 850 nm, 1310 nm and 1550 nm which are commonly used in optics communication. Generally, the metal electrode was utilized for photodetector and there were lots of light being loss. In recent years, graphene is found to be a good conductive film. It is a two-dimensional monolayer of sp2-bonded carbon atoms. In cases where synthesized by chemical vapor deposition (CVD), graphene is especially a promising candidate for transparent conductive films (TCFs) due to its exceptional electrical conductivity and high optical transmittance which is almost transparent in the wide wavelength range, especially including near infrared. Therefore, the higher photo current and responsivity of the device can be achieved. In this investigation, interdigitated graphene electrodes are used on the devices with the purposes of a relatively easy process for high-speed devices and a comparable process for the integrated circuit. We used the n-type Germanium as the substrates for the absorption of photodetector and different layers of graphene as the interdigitated electrodes. The interdigitated graphene electrode is prepared by transferred the graphene which is grown by CVD on the substrate first and then pattern by O2 plasma. The most direct method of measuring the photo current is to be incident a laser source by fiber and give a DC bias then using KEITHLEY 2400 Source Meter to measure current from photodetectors. As the result of that, we can calculate the responsivity by formula.

  12. Preliminary status of POLICAN: A near-infrared imaging polarimeter

    NASA Astrophysics Data System (ADS)

    Devaraj, R.; Luna, A.; Carrasco, L.; Mayya, Y. D.

    2015-10-01

    POLICAN is a near-infrared (J, H, K) imaging polarimeter developed for the Cananea near infrared camera (CANICA) at the 2.1m telescope of the Guillermo Haro Astrophysical Observatory (OAGH) located at Cananea, Sonora, México. The camera has a 1024 x 1024 HgCdTe detector (HAWAII array) with a plate scale of 0.32 arcsec/pixel providing a field of view of 5.5 x 5.5 arcmin. POLICAN is mounted externally to CANICA for narrow-field (f/12) linear polarimetric observations. It consists of a rotating super achromatic (1-2.7μm) half waveplate and a fixed wire-grid polarizer as the analyzer. The light is modulated by setting the half waveplate at different angles (0°, 22.5°, 45°, 67.5°) and linear combinations of the Stokes parameters (I, Q and U) are obtained. Image reduction and removal of instrumental polarization consist of dark noise subtraction, polarimetric flat fielding and background sky subtraction. Polarimetric calibration is performed by observing polarization standards available in the literature. The astrometry correction is performed by matching common stars with the Two Micron All Sky Survey. POLICAN's bright and limiting magnitudes are approximately 6th and 16th magnitude, which correspond to saturation and photon noise, respectively. POLICAN currently achieves a polarimetric accuracy about 3.0% and polarization angle uncertainties within 3°. Preliminary observations of star forming regions are being carried out in order to study their magnetic field properties.

  13. Optimal hemodynamic response model for functional near-infrared spectroscopy

    PubMed Central

    Kamran, Muhammad A.; Jeong, Myung Yung; Mannan, Malik M. N.

    2015-01-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging non-invasive brain imaging technique and measures brain activities by means of near-infrared light of 650–950 nm wavelengths. The cortical hemodynamic response (HR) differs in attributes at different brain regions and on repetition of trials, even if the experimental paradigm is kept exactly the same. Therefore, an HR model that can estimate such variations in the response is the objective of this research. The canonical hemodynamic response function (cHRF) is modeled by two Gamma functions with six unknown parameters (four of them to model the shape and other two to scale and baseline respectively). The HRF model is supposed to be a linear combination of HRF, baseline, and physiological noises (amplitudes and frequencies of physiological noises are supposed to be unknown). An objective function is developed as a square of the residuals with constraints on 12 free parameters. The formulated problem is solved by using an iterative optimization algorithm to estimate the unknown parameters in the model. Inter-subject variations in HRF and physiological noises have been estimated for better cortical functional maps. The accuracy of the algorithm has been verified using 10 real and 15 simulated data sets. Ten healthy subjects participated in the experiment and their HRF for finger-tapping tasks have been estimated and analyzed. The statistical significance of the estimated activity strength parameters has been verified by employing statistical analysis (i.e., t-value > tcritical and p-value < 0.05). PMID:26136668

  14. [Rapid determination of beet sugar content using near infrared spectroscopy].

    PubMed

    Yang, Yong; Ren, Jian; Zheng, Xi-Qun; Zhao, Li-Ying; Li, Mao-Mao

    2014-10-01

    In order to classify and set different prices on basis of difference of beet sugar content in the acquisition process and promote the development of beet sugar industry healthily, a fast, nondestructive, accurate method to detect sugar content of beet was determined by applying near infrared spectroscopy technology. Eight hundred twenty samples from 28 representative varieties of beet were collected as calibration set and 70 samples were chosen as prediction set. Then near infrared spectra of calibration set samples were collected by scanning, effective information was extracted from NIR spectroscopy, and the original spectroscopy data was optimized by data preprocessing methods appropriately. Then partial least square(PLS)regression was used to establish beet sugar quantitative prediction mathematical model. The performances of the models were evaluated by the root mean square of cross-validation (RMSECV), the coefficient of determination (R2) of the calibration model and the standard error of prediction (SEP), and the predicted results of these models were compared. Results show that the established mathematical model by using first derivative (FD) and standard normal variate transformation (SNV) coupled with partial least squares has good predictive ability. The R2 of calibration models of sugar content of beet is 0.908 3, and the RMSECV is 0.376 7. Using this model to forecast the prediction set including 70 samples, the correlation coefficient is 0.921 4 between predicted values and measured values, and the standard error of prediction (SEP) is 0.439, without significant difference (p > 0.05) between predicted values and measured values. These results demonstrated that NIRS can take advantage of simple, rapid, nondestructive and environmental detection method and could be applied to predict beet sugar content. This model owned high accuracy and can meet the precision need of determination of beet sugar content. This detection method could be used to classify

  15. Asteroid 951 Gaspra Near Infrared Mapping Spectrometer Radiance Data

    NASA Astrophysics Data System (ADS)

    Granahan, J. C., Jr.

    2015-12-01

    Five radiance spectra of asteroid 951 Gaspra have been archived in the Small Bodies Node of the NASA Planetary Data System [Granahan, 2014]. The radiance spectra were created from uncalibrated Galileo spacecraft Near Infrared Mapping Spectrometer files archived in the Imaging Node of the NASA Planetary Data System. The NASA Galileo spacecraft observed asteroid 951 Gaspra on October 29, 1991 with the Near Infrared Mapping Spectrometer (NIMS) at wavelengths ranging from 0.7 - 5.2 micrometers [Carlson et al., 1992]. The five radiance spectra consist of two 17, two 100, and one 329 spectral channel data sets. They record data that was acquired by NIMS at ranges between 27232.6 to 14723.8 kilometers from asteroid 951 Gaspra. The uncalibrated NIMS data were converted into radiance spectra using calibration coefficients obtained during the Galileo mission's first Earth encounter on December 8, 1990. The archived radiance spectral data is located at the URL (Universal Record Locator): http://sbn.psi.edu/pds/resource/gaspraspec.html and contains radiance, solar, incidence over flux, and data documentation. This archived data set contains a variety of spectral signatures. These signatures include absorptions near 1.0, 2.0, 2.8, 3.4, and 4.5 micrometers. The 1.0 and 2.0 micrometer features are indicators of olivine and pyroxene on the asteroid surface. The 2.8 micrometer feature has a shape similar to the combined spectra of multiple iron bearing phyllosilicates. The 3.4 micrometer feature is in the same location as absorptions created by a carbon-hydrogen bond. The 4.5 micrometer feature, present only in the 329 channel data set, corresponds in position to absorptions detected in sulfate minerals. Carlson, R. W., et al. (1992) Bull. of the A.A.S., 24, 932. Granahan, J. C. (2014), GO-A-NIMS-3-GASPRASPEC-V1.0, NASA Planetary Data System.

  16. YOUNG STELLAR OBJECT SEARCH TOWARD THE BOUNDARY OF THE CENTRAL MOLECULAR ZONE WITH NEAR-INFRARED POLARIMETRY

    SciTech Connect

    Yoshikawa, Tatsuhito; Nagata, Tetsuya; Nishiyama, Shogo; Kwon, Jungmi; Tamura, Motohide E-mail: nagata@kusastro.kyoto-u.ac.jp

    2014-08-01

    We have carried out near-infrared polarimetry toward the boundary of the Central Molecular Zone, in the field of (–1.°4 ≲ l ≲ –0.°3 and 1.°0 ≲ l ≲ 2.°9, |b| ≲ 0.°1), using the near-infrared polarimetric camera SIRPOL on the 1.4 m Infrared Survey Facility telescope. We have selected 112 intrinsically polarized sources on the basis of the estimate of interstellar polarization on Stokes Q/I – U/I planes. The selected sources are brighter than K{sub S} = 14.5 mag and have polarimetric uncertainty δP < 1%. Ten of these distinctive polarized sources are fit well with spectral energy distributions of young stellar objects when using the photometry in the archive of the Spitzer Space Telescope mid-infrared data. However, many sources have spectral energy distributions of normal stars suffering from heavy interstellar extinction; these might be stars behind dark clouds. Due to the small number of distinctive polarized sources and candidates of young stellar objects, we cannot judge if they are declining in number outside the Central Molecular Zone. Many massive candidates for young stellar objects in the literature have only small intrinsic polarization. This might suggest that their masses are 4-15 M {sub ☉}, whose intrinsic polarization has been expected to be small.

  17. A knot in the protein structure - probing the near-infrared fluorescent protein iRFP designed from a bacterial phytochrome.

    PubMed

    Stepanenko, Olesya V; Bublikov, Grigory S; Stepanenko, Olga V; Shcherbakova, Daria M; Verkhusha, Vladislav V; Turoverov, Konstantin K; Kuznetsova, Irina M

    2014-05-01

    The possibility of engineering near-infrared fluorescent proteins and biosensors from bacterial phytochrome photoreceptors (BphPs) has led to substantial interest in this family of proteins. The near-infrared fluorescent proteins have allowed non-invasive bio-imaging of deep tissues and whole organs in living animals. BphPs and derived near-infrared fluorescent proteins contain a structural element, called a knot, in their polypeptide chains. The formation of knot structures in proteins was refuted for a long time. Here, we studied the denaturation and renaturation processes of the near-infrared fluorescent probe iRFP, engineered from RpBphP2, which utilizes a heme-derived tetrapyrrole compound biliverdin as a chromophore. iRFP contains a unique figure-of-eight knot. The denaturation and renaturation curves of the iRFP apoform coincided well, suggesting efficient refolding. However, the iRFP holoform exhibited irreversible unfolding and aggregation associated with the bound chromophore. The knot structure in the apoform did not prevent subsequent binding of biliverdin, resulting in the functional iRFP holoform. We suggest that the irreversibility of protein unfolding is caused by post-translational protein modifications, such as chromophore binding, rather than the presence of the knot. These results are essential for future design of BphP-based near-infrared probes, and add important features to our knowledge of protein folding.

  18. Near Infrared photometric and spectroscopic observations of the bright optical transient J212444.87+321738.3

    NASA Astrophysics Data System (ADS)

    Mondal, Soumen; Das, Ramkrishna; Ashok, N. M.; Banerjee, D. P. K.; Dutta, Somnath; Ghosh, Supriyo; Mondal, Anindita

    2013-04-01

    We report near infrared JHK-band photometry and spectroscopic observations of the recently reported bright optical transient J212444.87+321738.3 using the Near-IR Imager cum spectrograph (NICMOS-3) installed on the Mount Abu 1.2-m telescope of the Physical Research Laboratory, India following the outburst announcement by Tiurina et al. in ATel #4888. The photometric observations were carried out on 2013 March 21.020 UT and 23.010 UT yielding magnitudes of J = 5.85 +/- 0.06, H = 4.47 +/- 0.06, K = 3.77 +/- 0.05; and J= 5.64 +/- 0.04, H= 4.48 +/- 0.04, K = 3.77 +/- 0.03 respectively.

  19. A near-infrared magnetic aptasensor for Ochratoxin A based on near-infrared upconversion nanoparticles and magnetic nanoparticles.

    PubMed

    Dai, Shaoliang; Wu, Shijia; Duan, Nuo; Wang, Zhouping

    2016-09-01

    A multiplexed, sensitive and specific detection method is highly desirable for the simultaneous detection of several pathogenic bacteria and bio-toxins. In our previous work, multicolor upconversion nanoparticles (UCNPs) via doping with various rare-earth ions to obtain well-separated emission peaks by means of a solvothermal method were synthesized and were successfully applied as luminescence labels in the detection of three pathogenic bacteria. One of the basic achievements of our group has been to establish that the key to increasing the number of simultaneous detection components is the preparation of more UCNPs, the emission peaks of which can be distinguished from each other. According to this vision, NaYF4:Yb0.2, Tm0.02 UCNPs were obtained via a thermal-decomposition protocol, which has a main near-infrared (NIR) UC emission at 804nm under 980nm excitation. The emission peak at 804nm was well-separated from the emission peaks of UCNPs we have reported at 477nm, 542nm, and 660nm. It means both the excitation and the emission of NaYF4:Yb0.2, Tm0.02 UCNPs are located in the NIR spectral range (NIR-to-NIR UC emission), the so-called biological window. This result establishes the basis of achieving simultaneous detection of four components. To confirm the analytical performance of this NaYF4:Yb0.2, Tm0.02 UCNPs, a novel near-infrared magnetic aptasensor for the detection of Ochratoxin A (OTA) was developed using the OTA aptamer-conjugated near-infrared upconversion nanoparticles (apt-UCNPs) and the complementary oligonucleotide-modified magnetic nanoparticles (cDNA-MNPs). The apt-UCNPs and cDNA-MNPs were hybridized to form a poly-network structure of MNP-UCNP nanocomposites. When the target OTA was introduced, the aptamer combined with the priority target and the cDNA-MNPs were replaced. The proposed method achieved a linear range between 0.01 and 100ngmL(-1), with a detection limit as low as 0.005ngmL(-1). Then, we successfully applied this method to measure

  20. EDGES: Deep Multi-Wavelength Photometry and Radial SED Analysis for NGC4485, NGC4490 and NGC5273

    NASA Astrophysics Data System (ADS)

    Gillian, Beltz-Mohrmann; Dale, Daniel A.; Barnes, Kate L.; Egan, Arika; Hatlestad, Alan; Herzog, Laura; Kobulnicky, Henry A.; Leung, Andrew S.; McLane, Jacob; Phenicie, Christopher; Roberts, Jareth; Staudaher, Shawn; van Zee, Liese

    2015-01-01

    New deep ugr imaging was obtained on the Wyoming Infrared Observatory 2.3 meter telescope for NGC4485, NGC4490 and NGC5273, three galaxies in the Extended Disk Galaxy Exploration Science survey. These data are coupled with deep GALEX ultraviolet and Spitzer/Herschel infrared imaging to study the radial variations in the spectral energy distributions. Results from the CIGALE SED modeling software will be presented, including trends in the galaxy star formation histories. This work is supported by the National Science Foundation under REU grant AST 1063146.

  1. Near-infrared-absorbing gold nanopopcorns with iron oxide cluster core for magnetically amplified photothermal and photodynamic cancer therapy.

    PubMed

    Bhana, Saheel; Lin, Gan; Wang, Lijia; Starring, Hunter; Mishra, Sanjay R; Liu, Gang; Huang, Xiaohua

    2015-06-03

    We present the synthesis and application of a new type of dual magnetic and plasmonic nanostructures for magnetic-field-guided drug delivery and combined photothermal and photodynamic cancer therapy. Near-infrared-absorbing gold nanopopcorns containing a self-assembled iron oxide cluster core were prepared via a seed-mediated growth method. The hybrid nanostructures are superparamagnetic and show great photothermal conversion efficiency (η=61%) under near-infrared irradiation. Compact and stable nanocomplexes for photothermal-photodynamic therapy were formed by coating the nanoparticles with near-infrared-absorbing photosensitizer silicon 2,3-naphthalocyannie dihydroxide and stabilization with poly(ethylene glycol) linked with 11-mercaptoundecanoic acid. The nanocomplex showed enhanced release and cellular uptake of the photosensitizer with the use of a gradient magnetic field. In vitro studies using two different cell lines showed that the dual mode photothermal and photodynamic therapy with the assistance of magnetic-field-guided drug delivery dramatically improved the therapeutic efficacy of cancer cells as compared to the combination treatment without using a magnetic field and the two treatments alone. The "three-in-one" nanocomplex has the potential to carry therapeutic agents deep into a tumor through magnetic manipulation and to completely eradicate tumors by subsequent photothermal and photodynamic therapies without systemic toxicity.

  2. Multifunctional in vivo vascular imaging using near-infrared II fluorescence

    PubMed Central

    Hong, Guosong; Lee, Jerry C.; Robinson, Joshua T.; Raaz, Uwe; Xie, Liming; Huang, Ngan F.; Cooke, John P.; Dai, Hongjie

    2013-01-01

    In vivo real-time epifluorescence imaging of mouse hindlimb vasculatures in the second near-infrared region (NIR-II, 1.1–1.4 µm) is performed using single-walled carbon nanotubes (SWNTs) as fluorophores. Both high spatial resolution (~30 µm) and temporal resolution (<200 ms/frame) for small vessel imaging are achieved 1~3 mm deep in the tissue owing to the beneficial NIR-II optical window that affords deep anatomical penetration and low scattering. This spatial resolution is unattainable by traditional NIR imaging (NIR-I, 0.75–0.9 µm) or microscopic computed tomography (micro-CT), while the temporal resolution far exceeds scanning microscopic imaging techniques. Arterial and venous vessels are unambiguously differentiated using a dynamic contrast-enhanced NIR-II imaging technique based on their distinct hemodynamics. Further, the deep tissue penetration, high spatial and temporal resolution of NIR-II imaging allow for precise quantifications of blood velocity in both normal and ischemic femoral arteries, which are beyond the capability of ultrasonography at lower blood velocity. PMID:23160236

  3. In vivo near-infrared fluorescence three-dimensional positioning system with binocular stereovision

    NASA Astrophysics Data System (ADS)

    Song, Bofan; Jin, Wei; Wang, Ying; Jin, Qinhan; Mu, Ying

    2014-11-01

    Fluorescence is a powerful tool for in-vivo imaging in living animals. The traditional in-vivo fluorescence imaging equipment is based on single-view two-dimensional imaging systems. However, they cannot meet the needs for accurate positioning during modern scientific research. A near-infrared in-vivo fluorescence imaging system is demonstrated, which has the capability of deep source signal detecting and three-dimensional positioning. A three-dimensional coordinates computing (TDCP) method including a preprocess algorithm is presented based on binocular stereo vision theory, to figure out the solution for diffusive nature of light in tissue and the emission spectra overlap of fluorescent labels. This algorithm is validated to be efficient to extract targets from multispectral images and determine the spot center of biological interests. Further data analysis indicates that this TDCP method could be used in three-dimensional positioning of the fluorescent target in small animals. The study also suggests that the combination of a large power laser and deep cooling charge-coupled device will provide an attractive approach for fluorescent detection from deep sources. This work demonstrates the potential of binocular stereo vision theory for three-dimensional positioning for living animal in-vivo imaging.

  4. Ultralow-Power Near Infrared Lamp Light Operable Targeted Organic Nanoparticle Photodynamic Therapy.

    PubMed

    Huang, Ling; Li, Zhanjun; Zhao, Yang; Zhang, Yuanwei; Wu, Shuang; Zhao, Jianzhang; Han, Gang

    2016-11-09

    Tissue penetration depth is a major challenge in practical photodynamic therapy (PDT). A biocompatible and highly effective near infrared (NIR)-light-absorbing carbazole-substituted BODIPY (Car-BDP) molecule is reported as a class of imaging-guidable deep-tissue activatable photosensitizers for PDT. Car-BDP possesses an intense, broad NIR absorption band (600-800 nm) with a remarkably high singlet oxygen quantum yield (ΦΔ = 67%). After being encapsulated with biodegradable PLA-PEG-FA polymers, Car-BDP can form uniform and small organic nanoparticles that are water-soluble and tumor-targetable. Rather than using laser light, such nanoparticles offer an unprecedented deep-tissue, tumor targeting photodynamic therapeutic effect by using an exceptionally low-power-density and cost-effective lamp light (12 mW cm(-2)). In addition, these nanoparticles can be simultaneously traced in vivo due to their excellent NIR fluorescence. This study signals a major step forward in photodynamic therapy by developing a new class of NIR-absorbing biocompatible organic nanoparticles for effective targeting and treatment of deep-tissue tumors. This work also provides a potential new platform for precise tumor-targeting theranostics and novel opportunities for future affordable clinical cancer treatment.

  5. Non-thermal DNA damage of cancer cells using near-infrared irradiation.

    PubMed

    Tanaka, Yohei; Tatewaki, Naoto; Nishida, Hiroshi; Eitsuka, Takahiro; Ikekawa, Nobuo; Nakayama, Jun

    2012-08-01

    Previously, we reported that near-infrared irradiation that simulates solar near-infrared irradiation with pre- and parallel-irradiational cooling can non-thermally induce cytocidal effects in cancer cells. To explore these effects, we assessed cell viability, DNA damage response pathways, and the percentage of mitotic cancer cells after near-infrared treatment. Further, we evaluated the anti-cancer effects of near-infrared irradiation compared with doxorubicin in xenografts in nude mice by measuring tumor volume and assessing protein phosphorylation by immunoblot analysis. The cell viability of A549 lung adenocarcinoma cells was significantly decreased after three rounds of near-infrared irradiation at 20 J/cm(2). Apoptotic cells were observed in near-infrared treated cells. Moreover, near-infrared treatment increased the phosphorylation of ataxia-telangiectasia mutated (ATM) at Ser(1981), H2AX at Ser(139), Chk1 at Ser(317), structural maintenance of chromosome (SMC) 1 at Ser(966), and p53 at Ser(15) in A549 cells compared with control. Notably, near-infrared treatment induced the formation of nucleic foci of γH2AX. The percentage of mitotic A549 cells, as measured by histone H3 phosphorylation, decreased significantly after three rounds of near-infrared irradiation at 20 J/cm(2). Both near-infrared and doxorubicin inhibited the tumor growth of MDA-MB435 melanoma cell xenografts in nude mice and increased the phosphorylation of p53 at Ser(15), Chk1 at Ser(317), SMC1 at Ser(966), and H2AX at Ser(139) compared with control mice. These results indicate that near-infrared irradiation can non-thermally induce cytocidal effects in cancer cells as a result of activation of the DNA damage response pathway. The near-infrared irradiation schedule used here reduces discomfort and side effects. Therefore, this strategy may have potential application in the treatment of cancer.

  6. The ROSAT Deep Survey. 2; Optical Identification, Photometry and Spectra of X-Ray Sources in the Lockman Field

    NASA Technical Reports Server (NTRS)

    Schmidt, M.; Hasinger, G.; Gunn, J.; Schneider, D.; Burg, R.; Giacconi, R.; Lehmann, I.; MacKenty, J.; Truemper, J.; Zamorani, G.

    1998-01-01

    The ROSAT Deep Survey includes a complete sample of 50 X-ray sources with fluxes in the 0.5 - 2 keV band larger than 5.5 x 10(exp -15)erg/sq cm/s in the Lockman field (Hasinger et al., Paper 1). We have obtained deep broad-band CCD images of the field and spectra of many optical objects near the positions of the X-ray sources. We define systematically the process leading to the optical identifications of the X-ray sources. For this purpose, we introduce five identification (ID) classes that characterize the process in each case. Among the 50 X-ray sources, we identify 39 AGNs, 3 groups of galaxies, 1 galaxy and 3 galactic stars. Four X-ray sources remain unidentified so far; two of these objects may have an unusually large ratio of X-ray to optical flux.

  7. Gratings and Random Reflectors for Near-Infrared PIN Diodes

    NASA Technical Reports Server (NTRS)

    Gunapala, Sarath; Bandara, Sumith; Liu, John; Ting, David

    2007-01-01

    Crossed diffraction gratings and random reflectors have been proposed as means to increase the quantum efficiencies of InGaAs/InP positive/intrinsic/ negative (PIN) diodes designed to operate as near-infrared photodetectors. The proposal is meant especially to apply to focal-plane imaging arrays of such photodetectors to be used for near-infrared imaging. A further increase in quantum efficiency near the short-wavelength limit of the near-infrared spectrum of such a photodetector array could be effected by removing the InP substrate of the array. The use of crossed diffraction gratings and random reflectors as optical devices for increasing the quantum efficiencies of quantum-well infrared photodetectors (QWIPs) was discussed in several prior NASA Tech Briefs articles. While the optical effects of crossed gratings and random reflectors as applied to PIN photodiodes would be similar to those of crossed gratings and random reflectors as applied to QWIPs, the physical mechanisms by which these optical effects would enhance efficiency differ between the PIN-photodiode and QWIP cases: In a QWIP, the multiple-quantum-well layers are typically oriented parallel to the focal plane and therefore perpendicular or nearly perpendicular to the direction of incidence of infrared light. By virtue of the applicable quantum selection rules, light polarized parallel to the focal plane (as normally incident light is) cannot excite charge carriers and, hence, cannot be detected. A pair of crossed gratings or a random reflector scatters normally or nearly normally incident light so that a significant portion of it attains a component of polarization normal to the focal plane and, hence, can excite charge carriers. A pair of crossed gratings or a random reflector on a PIN photodiode would also scatter light into directions away from the perpendicular to the focal plane. However, in this case, the reason for redirecting light away from the perpendicular is to increase the length of the

  8. Reversibly switchable photoacoustic tomography using a genetically encoded near-infrared phytochrome

    NASA Astrophysics Data System (ADS)

    Yao, Junjie; Kaberniuk, Andrii A.; Li, Lei; Shcherbakova, Daria M.; Zhang, Ruiying; Wang, Lidai; Li, Guo; Verkhusha, Vladislav V.; Wang, Lihong V.

    2016-03-01

    Optical imaging of genetically encoded probes has revolutionized biomedical studies by providing valuable information about targeted biological processes. Here, we report a novel imaging technique, termed reversibly switchable photoacoustic tomography (RS-PAT), which exhibits large penetration depth, high detection sensitivity, and super-resolution. RS-PAT combines advanced photoacoustic imaging techniques with, for the first time, a nonfluorescent photoswitchable bacterial phytochrome. This bacterial phytochrome is the most near-infrared shifted genetically encoded probe reported so far. Moreover, this bacterial phytochrome is reversibly photoconvertible between its far-red and near-infrared light absorption states. Taking maximum advantage of the powerful imaging capability of PAT and the unique photochemical properties of the phytochrome, RS-PAT has broken through both the optical diffusion limit for deep-tissue imaging and the optical diffraction limit for super-resolution photoacoustic microscopy. Specifically, with RS-PAT we have achieved an unprecedented detection sensitivity of ~2 μM, or as few as ~20 tumor cells, at a centimeter depth. Such high sensitivity is fully demonstrated in our study by monitoring tumor growth and metastasis at whole-body level with ~100 μm resolution. Moreover, our microscopic implementation of RS-PAT is capable of imaging mammalian cells with a sub-diffraction lateral resolution of ~140 nm and axial resolution of ~400 nm, which are respectively ~2-fold and ~75-fold finer than those of our conventional photoacoustic microscopy. Overall, RS-PAT is a new and promising imaging technology for studying biological processes at different length scales.

  9. Intraoperative near-infrared fluorescent imaging during robotic operations.

    PubMed

    Macedo, Antonio Luiz de Vasconcellos; Schraibman, Vladimir

    2016-01-01

    The intraoperative identification of certain anatomical structures because they are small or visually occult may be challenging. The development of minimally invasive surgery brought additional difficulties to identify these structures due to the lack of complete tactile sensitivity. A number of different forms of intraoperative mapping have been tried. Recently, the near-infrared fluorescence imaging technology with indocyanine green has been added to robotic platforms. In addition, this technology has been tested in several types of operations, and has advantages such as safety, low cost and good results. Disadvantages are linked to contrast distribution in certain clinical scenarios. The intraoperative near-infrared fluorescent imaging is new and promising addition to robotic surgery. Several reports show the utility of this technology in several different procedures. The ideal dose, time and site for dye injection are not well defined. No high quality evidence-based comparative studies and long-term follow-up outcomes have been published so far. Initial results, however, are good and safe. RESUMO A identificação intraoperatória de certas estruturas anatômicas, por seu tamanho ou por elas serem ocultas à visão, pode ser desafiadora. O desenvolvimento da cirurgia minimamente invasiva trouxe dificuldades adicionais, pela falta da sensibilidade tátil completa. Diversas formas de detecção intraoperatória destas estruturas têm sido tentadas. Recentemente, a tecnologia de fluorescência infravermelha com verde de indocianina foi associada às plataformas robóticas. Além disso, essa tecnologia tem sido testada em uma variedade de cirurgias, e suas vantagens parecem estar ligadas a baixo custo, segurança e bons resultados. As desvantagens estão associadas à má distribuição do contraste em determinados cenários. A imagem intraoperatória por fluorescência infravermelha é uma nova e promissora adição à cirurgia robótica. Diversas séries mostram

  10. The near infrared camera for the Subaru Prime Focus Spectrograph

    NASA Astrophysics Data System (ADS)

    Smee, Stephen A.; Gunn, James E.; Golebiowski, Mirek; Barkhouser, Robert; Vivès, Sebastien; Pascal, Sandrine; Carr, Michael; Hope, Stephen C.; Loomis, Craig; Hart, Murdock; Sugai, Hajime; Tamura, Naoyuki; Shimono, Atsushi

    2014-08-01

    We present the detailed design of the near infrared camera for the SuMIRe (Subaru Measurement of Images and Redshifts) Prime Focus Spectrograph (PFS) being developed for the Subaru Telescope. The PFS spectrograph is designed to collect spectra from 2394 objects simultaneously, covering wavelengths that extend from 380 nm - 1.26 μm. The spectrograph is comprised of four identical spectrograph modules, with each module collecting roughly 600 spectra from a robotic fiber positioner at the telescope prime focus. Each spectrograph module will have two visible channels covering wavelength ranges 380 nm - 640 nm and 640 nm - 955 nm, and one near infrared (NIR) channel with a wavelength range 955 nm - 1.26 μm. Dispersed light in each channel is imaged by a 300 mm focal length, f/1.07, vacuum Schmidt camera onto a 4k x 4k, 15 µm pixel, detector format. For the NIR channel a HgCdTe substrate-removed Teledyne 1.7 μm cutoff device is used. In the visible channels, CCDs from Hamamatsu are used. These cameras are large, having a clear aperture of 300 mm at the entrance window, and a mass of ~ 250 kg. Like the two visible channel cameras, the NIR camera contains just four optical elements: a two-element refractive corrector, a Mangin mirror, and a field flattening lens. This simple design produces very good imaging performance considering the wide field and wavelength range, and it does so in large part due to the use of a Mangin mirror (a lens with a reflecting rear surface) for the Schmidt primary. In the case of the NIR camera, the rear reflecting surface is a dichroic, which reflects in-band wavelengths and transmits wavelengths beyond 1.26 μm. This, combined with a thermal rejection filter coating on the rear surface of the second corrector element, greatly reduces the out-of-band thermal radiation that reaches the detector. The camera optics and detector are packaged in a cryostat and cooled by two Stirling cycle cryocoolers. The first corrector element serves as the

  11. High Speed Photometry for BUSCA

    NASA Astrophysics Data System (ADS)

    Cordes, O.; Reif, K.

    The camera BUSCA (Bonn University Simultaneous CAmera) is a standard instrument at the 2.2m telescope at Calar Alto Observatory (Spain) since 2001. At the moment some modifications of BUSCA are planned and partially realised. One major goal is the replacement of the old thick CCDs in the blue, yellow-green, and near-infrared channels. The newer CCDs have better cosmetics and performance in sensitivity. The other goal is to replace the old "Heidelberg"-style controller with a newly designed controller with the main focus on high-speed readout and on an advanced windowing mechanism. We present a theoretical analysis of the new controller design and its advantage in high speed photometry of rapidly pulsating stars. As an example PG1605+072 was chosen which was observed with BUSCA before in 2001 and 2002.

  12. Near-infrared light-responsive nanomaterials in cancer therapeutics.

    PubMed

    Shanmugam, Vijayakumar; Selvakumar, S; Yeh, Chen-Sheng

    2014-09-07

    Noninvasive techniques, such as breath tests (urea breath test), blood pressure measurements using a sphygmomanometer and electrocardiography, were employed by a physician to perform classical diagnosis. The use of state-of-the-art noninvasive therapies at the organ level in modern medicine has gradually become possible. However, cancer treatment demands spatially and temporally controlled noninvasive therapy at the cell level because nonspecific toxicity often causes complicated side effects. To increase survival in cancer patients further, combination therapy and combination drugs are explored which demand high specificity to avoid combined-drug side effects. We believe that high specificity could be obtained by implementing near-infrared (NIR) light-assisted nanoparticles in photothermal therapy, chemotherapy, and photodynamic therapy. To refine this therapy and subsequently achieve high efficiency, novel nanomaterials have been designed and modified either to enhance the uptake and drug delivery to the cancer site, or control treatment to administer therapy efficiently. These modifications and developments have been demonstrated to achieve spatial and temporal control when conducting an in vivo xenograft, because the NIR light penetrated effectively the biological tissue. The nanoplatforms discussed in this review are grouped under the following subheadings: Au nanorods (NRs), Au nanoshells, other Au-related nanomaterials, graphene oxide, upconversion nanoparticles, and other related materials (including materials such as CuS, Fe3O4-related systems, and carbon nanotubes (CNTs)).

  13. Bundled-Optode Method in Functional Near-Infrared Spectroscopy

    PubMed Central

    Nguyen, Hoang-Dung; Hong, Keum-Shik; Shin, Yong-Il

    2016-01-01

    In this paper, a theory for detection of the absolute concentrations of oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbR) from hemodynamic responses using a bundled-optode configuration in functional near-infrared spectroscopy (fNIRS) is proposed. The proposed method is then applied to the identification of two fingers (i.e., little and thumb) during their flexion and extension. This experiment involves a continuous-wave-type dual-wavelength (760 and 830 nm) fNIRS and five healthy male subjects. The active brain locations of two finger movements are identified based on the analysis of the t- and p-values of the averaged HbOs, which are quite distinctive. Our experimental results, furthermore, revealed that the hemodynamic responses of two-finger movements are different: The mean, peak, and time-to-peak of little finger movements are higher than those of thumb movements. It is noteworthy that the developed method can be extended to 3-dimensional fNIRS imaging. PMID:27788178

  14. Near-infrared autofluorescence for the detection of parathyroid glands.

    PubMed

    Paras, Constantine; Keller, Matthew; White, Lisa; Phay, John; Mahadevan-Jansen, Anita

    2011-06-01

    A major challenge in endocrine surgery is the intraoperative detection of parathyroid glands during both thyroidectomies and parathyroidectomies. Current localization techniques such as ultrasound and sestamibi scan are mostly preoperative and rely on an abnormal parathyroid for its detection. In this paper, we present near-infrared (NIR) autofluorescence as a nonintrusive, real-time, automated in vivo method for the detection of the parathyroid gland. A pilot in vivo study was conducted to assess the ability of NIR fluorescence to identify parathyroid glands during thyroid and parathyroidectomies. Fluorescence measurements at 785 nm excitation were obtained intra-operatively from the different tissues exposed in the neck region in 21 patients undergoing endocrine surgery. The fluorescence intensity of the parathyroid gland was found to be consistently greater than that of the thyroid and all other tissues in the neck of all patients. In particular, parathyroid fluorescence was two to eleven times higher than that of the thyroid tissues with peak fluorescence occurring at 820 to 830 nm. These results indicate that NIR fluorescence has the potential to be an excellent optical tool to locate parathyroid tissue during surgery.

  15. Retinal-Based Proton Pumping in the Near Infrared.

    PubMed

    Ganapathy, Srividya; Venselaar, Hanka; Chen, Que; de Groot, Huub J M; Hellingwerf, Klaas J; de Grip, Willem J

    2017-02-15

    Proteorhodopsin (PR) and Gloeobacter rhodopsin (GR) are retinal-based light-driven proton pumps that absorb visible light (maxima at 520-540 nm). Shifting the action spectra of these proton pumps beyond 700 nm would generate new prospects in optogenetics, membrane sensor technology, and complementation of oxygenic phototrophy. We therefore investigated the effect of red-shifting analogues of retinal, combined with red-shifting mutations, on the spectral properties and pump activity of the resulting pigments. We investigated a variety of analogues, including many novel ones. One of the novel analogues we tested, 3-methylamino-16-nor-1,2,3,4-didehydroretinal (MMAR), produced exciting results. This analogue red-shifted all of the rhodopsin variants tested, accompanied by a strong broadening of the absorbance band, tailing out to 850-950 nm. In particular, MMAR showed a strong synergistic effect with the PR-D212N,F234S double mutant, inducing an astonishing 200 nm red shift in the absorbance maximum. To our knowledge, this is by far the largest red shift reported for any retinal protein. Very importantly, all MMAR-containing holoproteins are the first rhodopsins retaining significant pump activity under near-infrared illumination (730 nm light-emitting diode). Such MMAR-based rhodopsin variants present very promising opportunities for further synthetic biology modification and for a variety of biotechnological and biophysical applications.

  16. Graphene surface plasmons at the near-infrared optical regime

    PubMed Central

    Zhang, Qiming; Li, Xiangping; Hossain, Md Muntasir; Xue, Yunzhou; Zhang, Jie; Song, Jingchao; Liu, Jingying; Turner, Mark D.; Fan, Shanhui; Bao, Qiaoliang; Gu, Min

    2014-01-01

    Graphene has been identified as an emerging horizon for a nanoscale photonic platform because the Fermi level of intrinsic graphene can be engineered to support surface plasmons (SPs). The current solid back electrical gating and chemical doping methods cannot facilitate the demonstration of graphene SPs at the near-infrared (NIR) window because of the limited shift of the Fermi level. Here, we present the evidence for the existence of graphene SPs on a tapered graphene-silicon waveguide tip at a NIR wavelength, employing a surface carrier transfer method with molybdenum trioxides. The coupling between the graphene surface plasmons and the guiding mode in silicon waveguides allows for the observation of the concentrated field of the SPs in the tip by near-field scanning optical microscopy. Thus the hot spot from the concentrated SPs in the graphene layer can be used as a key experimental signature of graphene SPs. The NIR graphene SPs opens a new perspective for optical communications, optical sensing and imaging, and optical data storage with extreme spatial confinement, broad bandwidth and high tunability. PMID:25297570

  17. Broadband near-infrared metamaterial absorbers utilizing highly lossy metals

    PubMed Central

    Ding, Fei; Dai, Jin; Chen, Yiting; Zhu, Jianfei; Jin, Yi; Bozhevolnyi, Sergey I.

    2016-01-01

    Radiation absorbers have increasingly been attracting attention as crucial components for controllable thermal emission, energy harvesting, modulators, etc. However, it is still challenging to realize thin absorbers which can operate over a wide spectrum range. Here, we propose and experimentally demonstrate thin, broadband, polarization-insensitive and omnidirectional absorbers working in the near-infrared range. We choose titanium (Ti) instead of the commonly used gold (Au) to construct nano-disk arrays on the top of a silicon dioxide (SiO2) coated Au substrate, with the quality (Q) factor of the localized surface plasmon (LSP) resonance being decreased due to the intrinsic high loss of Ti. The combination of this low-Q LSP resonance and the propagating surface plasmon (PSP) excitation resonance, which occur at different wavelengths, is the fundamental origin of the broadband absorption. The measured (at normal light incidence) absorption is over 90% in the wavelength range from 900 nm to 1825 nm, with high absorption persisting up to the incident angle of ~40°. The demonstrated thin-film absorber configuration is relatively easy to fabricate and can be realized with other properly selected materials. PMID:28000718

  18. Retinal safety of near-infrared lasers in cataract surgery

    NASA Astrophysics Data System (ADS)

    Wang, Jenny; Sramek, Christopher; Paulus, Yannis M.; Lavinsky, Daniel; Schuele, Georg; Anderson, Dan; Dewey, David; Palanker, Daniel

    2012-09-01

    Femtosecond lasers have added unprecedented precision and reproducibility to cataract surgery. However, retinal safety limits for the near-infrared lasers employed in surgery are not well quantified. We determined retinal injury thresholds for scanning patterns while considering the effects of reduced blood perfusion from rising intraocular pressure and retinal protection from light scattering on bubbles and tissue fragments produced by laser cutting. We measured retinal damage thresholds of a stationary, 1030-nm, continuous-wave laser with 2.6-mm retinal spot size for 10- and 100-s exposures in rabbits to be 1.35 W (1.26 to 1.42) and 0.78 W (0.73 to 0.83), respectively, and 1.08 W (0.96 to 1.11) and 0.36 W (0.33 to 0.41) when retinal perfusion is blocked. These thresholds were input into a computational model of ocular heating to calculate damage threshold temperatures. By requiring the tissue temperature to remain below the damage threshold temperatures determined in stationary beam experiments, one can calculate conservative damage thresholds for cataract surgery patterns. Light scattering on microbubbles and tissue fragments decreased the transmitted power by 88% within a 12 deg angle, adding a significant margin for retinal safety. These results can be used for assessment of the maximum permissible exposure during laser cataract surgery under various assumptions of blood perfusion, treatment duration, and scanning patterns.

  19. Electro-optic sampling of near-infrared waveforms

    NASA Astrophysics Data System (ADS)

    Keiber, Sabine; Sederberg, Shawn; Schwarz, Alexander; Trubetskov, Michael; Pervak, Volodymyr; Krausz, Ferenc; Karpowicz, Nicholas

    2016-03-01

    Access to the complete electric field evolution of a laser pulse is essential for attosecond science in general, and for the scrutiny and control of electron phenomena in solid-state physics specifically. Time-resolved field measurements are routine in the terahertz spectral range, using electro-optic sampling (EOS), photoconductive switches and field-induced second harmonic generation. EOS in particular features outstanding sensitivity and ease of use, making it the basis of time-resolved spectroscopic measurements for studying charge carrier dynamics and active optical devices. In this Letter, we show that careful optical filtering allows the bandwidth of this technique to be extended to wavelengths as short as 1.2 μm (230 THz) with half-cycle durations 2.3 times shorter than the sampling pulse. In a proof-of-principle application, we measure the influence of optical parametric amplification (OPA) on the electric field dynamics of a few-cycle near-infrared (NIR) pulse.

  20. Near-infrared plasmonics with transparent conducting oxides (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kim, Jongbum; Kinsey, Nathaniel; DeVault, Clayton; Dutta, Aveek; Ferrera, Marcello; Shalaev, Vladimir; Boltasseva, Alexandra

    2016-04-01

    As a result of the significant attention in searching for alternative plasmonic materials for real-life nanophotonic devices, transparent conducting oxides (TCOs) have been proposed as promising constituent building blocks for telecommunication wavelengths. They are eminently practical materials because they are CMOS-compatible, can be grown on many different types of substrates, patterned by standard fabrication procedures, and integrated with many other standard technologies. Due to the ability of TCO nanostructures to support strong plasmonic resonance in the near infrared (NIR), metasurface devices, such as a quarter wave plate, have been demonstrated whose properties can be easily adjustable with post processing such as thermal annealing. Additionally, TCOs can be used as epsilon near zero (ENZ) materials in the NIR. From our recent study of the behavior of nanoantennae sitting upon a TCO substrate, we found that TCOs serve as an optical insulating media due to the high impedance of TCOs at the ENZ frequency, enabling emission shaping. Finally, the optical properties of TCOs can be varied by optical or electrical means. Current research is focused on studying the ultrafast carrier dynamics in doped zinc oxide films using pump-probe spectroscopy. We have shown that aluminum doped zinc oxide films can achieve a 40% change in reflection with ultrafast dynamics (<1ps) under a small fluence of 3mJ/cm2. Consequently, TCOs are shown to be extremely flexible materials, enabling fascinating physics and unique devices for applications in the NIR regime.

  1. Optically guided neuronal growth at near-infrared wavelengths

    NASA Astrophysics Data System (ADS)

    Stevenson, D. J.; Lake, T. K.; Agate, B.; Garcés-Chávez, V.; Dholakia, K.; Gunn-Moore, F.

    2006-08-01

    Recent work has indicated the potential of light to guide the growth cones of neuronal cells using a Ti:Sapphire laser at 800 nm (Ehrlicher et al, PNAS, 2002). We have developed an optical set-up that has allowed, for the first time, the direct comparison of this process at near infrared wavelengths. A high number of growth cones were studied in order to provide a detailed statistical analysis. Actively extending growth cones of the neuroblastoma cell-line, NG108, can be guided at not only 780 nm, but also at 1064 nm. These wavelengths are an appropriate choice for guidance experiments, as wavelengths in the visible spectrum and UV are highly absorbing by cells and lead to death by phototoxicity and thermal stress. At 780 nm, 47% of actively extending growth cones were found to turn towards the focused incident light by at least 30° (n=32 growth cones). At 1064 nm, 61% of cells were successfully guided (n=31 growth cones). This suggests that the light detection mechanism within the cell is not due a single protein with a defined activity wavelength as occurs for example with the photoreceptor family of opsin proteins in the mammalian eye. We present two novel mechanisms of light induced neuronal guidance which are not related to temperature increases, or optical tweezing of the growth cone. We are also now identifying the signaling pathways that mediate this phenomenon.

  2. Functional data analysis view of functional near infrared spectroscopy data.

    PubMed

    Barati, Zeinab; Zakeri, Issa; Pourrezaei, Kambiz

    2013-11-01

    Functional near infrared spectroscopy (fNIRS) is a powerful tool for the study of oxygenation and hemodynamics of living tissues. Despite the continuous nature of the processes generating the data, analysis of fNIRS data has been limited to discrete-time methods. We propose a technique, namely functional data analysis (fDA), that converts discrete samples to continuous curves. We used fNIRS data collected on forehead during a cold pressor test (CPT) from 20 healthy subjects. Using functional principal component analysis, oxyhemoglobin (HbO2) and deoxyhemoglobin (Hb) curves were decomposed into several components based on variability across the subjects. Each component corresponded to an experimental condition and provided qualitative and quantitative information of the shape and weight of that component. Furthermore, we applied functional canonical correlation analysis to investigate the interaction between Hb and HbO2 curves. We showed that the variation of Hb and HbO2 was positively correlated during the CPT, with a "far" channel on right forehead showing a smaller and faster HbO2 variation than Hb. This research suggests the fDA platform for the analysis of fNIRS data, which solves problem of high dimensionality, enables study of response dynamics, enhances characterization of the evoked response, and may improve design of future fNIRS experiments.

  3. Near-infrared spectroscopy of Type Ia supernovae

    NASA Astrophysics Data System (ADS)

    Hsiao, Eric; Phillips, Mark; Burns, Christopher R.; Contreras, Carlos; Gall, Christa; Hoeflich, Peter; Kirshner, Robert P.; Marion, Howie H.; Morrell, Nidia; Sand, David J.; Stritzinger, Maximillian; Carnegie Supernova Project

    2016-01-01

    Improving the cosmological experiments with Type Ia supernovae (SNe Ia) is now not simply a question of observing more supernovae, since any survey, no matter how large, will ultimately be limited by the systematic errors. It has been clearly demonstrated in a number of studies that SNe Ia are better distance indicators in the near-infrared compared to the optical. As exciting as these new results are, SNe Ia in the NIR are expected to be even better than these studies indicate. A key ingredient for improving SN Ia in the NIR as distance indicators is to obtain NIR spectroscopy to determine precise k-corrections, which account for the effect of cosmological expansion upon the measured magnitudes. Better knowledge of the NIR spectroscopic behaviors, akin to that in the optical, is necessary to reach the distance precision required to identify viable models for dark energy. Carnegie Supernova Project II has built a definitive data set, much improved from previous samples, both in size and quality. With this previously unavailable window, we are also beginning to gain new insight on the physics of these events.

  4. A near-Infrared SETI Experiment: Alignment and Astrometric precision

    NASA Astrophysics Data System (ADS)

    Duenas, Andres; Maire, Jerome; Wright, Shelley; Drake, Frank D.; Marcy, Geoffrey W.; Siemion, Andrew; Stone, Remington P. S.; Tallis, Melisa; Treffers, Richard R.; Werthimer, Dan

    2016-06-01

    Beginning in March 2015, a Near-InfraRed Optical SETI (NIROSETI) instrument aiming to search for fast nanosecond laser pulses, has been commissioned on the Nickel 1m-telescope at Lick Observatory. The NIROSETI instrument makes use of an optical guide camera, SONY ICX694 CCD from PointGrey, to align our selected sources into two 200µm near-infrared Avalanche Photo Diodes (APD) with a field-of-view of 2.5"x2.5" each. These APD detectors operate at very fast bandwidths and are able to detect pulse widths extending down into the nanosecond range. Aligning sources onto these relatively small detectors requires characterizing the guide camera plate scale, static optical distortion solution, and relative orientation with respect to the APD detectors. We determined the guide camera plate scale as 55.9+- 2.7 milli-arcseconds/pixel and magnitude limit of 18.15mag (+1.07/-0.58) in V-band. We will present the full distortion solution of the guide camera, orientation, and our alignment method between the camera and the two APDs, and will discuss target selection within the NIROSETI observational campaign, including coordination with Breakthrough Listen.

  5. Near-infrared light activated delivery platform for cancer therapy.

    PubMed

    Lin, Min; Gao, Yan; Hornicek, Francis; Xu, Feng; Lu, Tian Jian; Amiji, Mansoor; Duan, Zhenfeng

    2015-12-01

    Cancer treatment using conventional drug delivery platforms may lead to fatal damage to normal cells. Among various intelligent delivery platforms, photoresponsive delivery platforms are becoming popular, as light can be easily focused and tuned in terms of power intensity, wavelength, and irradiation time, allowing remote and precise control over therapeutic payload release both spatially and temporally. This unprecedented controlled delivery manner is important to improve therapeutic efficacy while minimizing side effects. However, most of the existing photoactive delivery platforms require UV/visible excitation to initiate their function, which suffers from phototoxicity and low level of tissue penetration limiting their practical applications in biomedicine. With the advanced optical property of converting near infrared (NIR) excitation to localized UV/visible emission, upconversion nanoparticles (UCNPs) have emerged as a promising photoactive delivery platform that provides practical applications for remote spatially and temporally controlled release of therapeutic payload molecules using low phototoxic and high tissue penetration NIR light as the excitation source. This article reviews the state-of-the-art design, synthesis and therapeutic molecular payload encapsulation strategies of UCNP-based photoactive delivery platforms for cancer therapy. Challenges and promises for engineering of advanced delivery platforms are also highlighted.

  6. Fully Automated Lipid Pool Detection Using Near Infrared Spectroscopy

    PubMed Central

    Wojakowski, Wojciech

    2016-01-01

    Background. Detecting and identifying vulnerable plaque, which is prone to rupture, is still a challenge for cardiologist. Such lipid core-containing plaque is still not identifiable by everyday angiography, thus triggering the need to develop a new tool where NIRS-IVUS can visualize plaque characterization in terms of its chemical and morphologic characteristic. The new tool can lead to the development of new methods of interpreting the newly obtained data. In this study, the algorithm to fully automated lipid pool detection on NIRS images is proposed. Method. Designed algorithm is divided into four stages: preprocessing (image enhancement), segmentation of artifacts, detection of lipid areas, and calculation of Lipid Core Burden Index. Results. A total of 31 NIRS chemograms were analyzed by two methods. The metrics, total LCBI, maximal LCBI in 4 mm blocks, and maximal LCBI in 2 mm blocks, were calculated to compare presented algorithm with commercial available system. Both intraclass correlation (ICC) and Bland-Altman plots showed good agreement and correlation between used methods. Conclusions. Proposed algorithm is fully automated lipid pool detection on near infrared spectroscopy images. It is a tool developed for offline data analysis, which could be easily augmented for newer functions and projects. PMID:27610191

  7. Rapid analysis of Radix puerariae by near-infrared spectroscopy.

    PubMed

    Lau, Ching-Ching; Chan, Chi-On; Chau, Foo-Tim; Mok, Daniel Kam-Wah

    2009-03-13

    A new, rapid analytical method using near-infrared spectroscopy (NIRS) was developed to differentiate two species of Radix puerariae (GG), Pueraria lobata (YG) and Pueraria thomsonii (FG), and to determine the contents of puerarin, daidzin and total isoflavonoid in the samples. Five isoflavonoids, puerarin, daidzin, daidzein, genistin and genistein were analyzed simultaneously by high-performance liquid chromatography-diode array detection (HPLC-DAD). The total isoflavonoid content was exploited as critical parameter for successful discrimination of the two species. Scattering effect and baseline shift in the NIR spectra were corrected and the spectral features were enhanced by several pre-processing methods. By using linear discriminant analysis (LDA) and soft independent modeling class analogy (SIMCA), samples were separated successfully into two different clusters corresponding to the two GG species. Furthermore, sensitivity and specificity of the classification models were determined to evaluate the performance. Finally, partial least squares (PLS) regression was used to build the correlation models. The results showed that the correlation coefficients of the prediction models are R=0.970 for the puerarin, R=0.939 for daidzin and R=0.969 for total isoflavonoid. The outcome showed that NIRS can serve as routine screening in the quality control of Chinese herbal medicine (CHM).

  8. Near infrared light responsive hybrid nanoparticles for synergistic therapy.

    PubMed

    Liang, Yan; Gao, Wenxia; Peng, Xinyu; Deng, Xin; Sun, Changzhen; Wu, Huayue; He, Bin

    2016-09-01

    A near infrared (NIR) light responsive chromophore 7-(diethylamino)-4-(hydroxymethyl)-2H-chromen-2-one (DEACM) was synthesized and incorporated to β-cyclodextrins with cRGD functionalized poly(ethylene glycol), the amphiphiles were coordinated with Au nanorods or nanoparticles to load anticancer drug doxorubicin (DOX) for fabricating hybrid nanoparticles. The π-π stacking interaction between DEACM and DOX was formed in the hybrid nanoparticles, which contributed to the high drug loading content. The Au nanorods or nanoparticles enhanced the photosolvolysis of DEACM under the irradiation of NIR with 808 nm wavelength and triggered the accelerated drug release from the nanoparticles. The drug loaded hybrid nanoparticles with NIR irradiation exhibited efficient inhibition effect on the proliferation of 4T1 breast cancer cells in vitro. The in vivo anticancer activity study on breast cancer bearing mice revealed that the hybrid nanoparticles containing Au nanorods exhibited excellent anticancer activity under the irradiation of 808 nm wavelength NIR with 800 mW.

  9. Studying hot exozodiacal dust with near-infrared interferometry

    NASA Astrophysics Data System (ADS)

    Absil, Olivier; Defrère, Denis; Le Bouquin, Jean-Baptiste; Mollier, Benjamin; Augereau, Jean-Charles; Coudé du Foresto, Vincent; Di Folco, Emmanuel; Ertel, Steve; ten Brummelaar, Theo

    2012-07-01

    Since our first detection of a resolved near-infrared emission around the main sequence star Vega, which we identified as the signature of hot dust grains close to the sublimation limit, we have been systematically searching for similar signatures around a magnitude-limited sample of nearby main sequence stars with the FLUOR instrument at the CHARA array. About 40 targets with spectral types ranging from A to K have been observed within the last 6 years, leading to first statistical trends on the occurence of the bright exozodi phenomenon as a function of spectral type. Our target sample is balanced between stars known to harbour cold dust populations from space-based missions (e.g., Spitzer, Herschel) and stars without cold dust, so that the occurence of abundant hot dust can also be correlated with the presence of large reservoirs of cold planetesimals. In this paper, we present preliminary conclusions from the CHARA/FLUOR survey. We also discuss the first results obtained in 2011/2012 with the new PIONIER visiting instrument at the VLTI, which is now used to extend our survey sample to the Southern hemisphere and to fainter targets. A first measurement of the exozodi/star flux ratio as a function of wavelength within the H band is presented, thanks to the low spectral resolution capability of PIONIER. Finally, we also briefly discuss our plans for extending the survey to fainter targets in the Northern hemisphere with an upgraded version of the FLUOR beam combiner.

  10. Near-infrared mapping spectrometer optical subsystem development and testing

    NASA Technical Reports Server (NTRS)

    Macenka, S. A.

    1983-01-01

    The Near-Infrared Mapping Spectrometer (NIMS) is one of the four remote-sensing science instruments of the Galileo Orbiter scientific payload. The NIMS scientific objectives require operating the detector and optical subsystem at cryogenic temperatures. The necessity of assembling, aligning, and testing the optics at room temperature and meeting design specifications at the cryogenic operating temperature (130 K) presented a set of challenging technical problems. A systematic approach to the development of athermalized mounts and supporting structures for optical components is described. A technique utilizing the visible spectral range and supplementary ray-trace information for alignment of an infrared instrument is presented. The optical subsystem point-spread function and spatial and spectral resolution were determined at room temperature using selected spectral and spatial targets. Based on thermal-distortion analyses of the structure and mounts, compensators were selected, implemented, and verified at cryogenic temperatures. The selection of the compensator and the overall system performance were verified in a thermal vacuum chamber. Various external and internal calibration targets were used.

  11. Silicon photonic crystal thermal emitter at near-infrared wavelengths.

    PubMed

    O'Regan, Bryan J; Wang, Yue; Krauss, Thomas F

    2015-08-21

    Controlling thermal emission with resonant photonic nanostructures has recently attracted much attention. Most of the work has concentrated on the mid-infrared wavelength range and/or was based on metallic nanostructures. Here, we demonstrate the experimental operation of a resonant thermal emitter operating in the near-infrared (≈1.5 μm) wavelength range. The emitter is based on a doped silicon photonic crystal consisting of a two dimensional square array of holes and using silicon-on-insulator technology with a device-layer thickness of 220 nm. The device is resistively heated by passing current through the photonic crystal membrane. At a temperature of ≈1100 K, we observe relatively sharp emission peaks with a Q factor around 18. A support structure system is implemented in order to achieve a large area suspended photonic crystal thermal emitter and electrical injection. The device demonstrates that weak absorption together with photonic resonances can be used as a wavelength-selection mechanism for thermal emitters, both for the enhancement and the suppression of emission.

  12. Measurement of subcutaneous adipose tissue thickness by near-infrared.

    PubMed

    Wang, Yu; Yang, Zeqiang; Hao, Dongmei; Zhang, Song; Yang, Yimin; Zeng, Yanjun

    2013-06-01

    Obesity is strongly associated with the risks of diabetes and cardiovascular disease, and there is a need to measure the subcutaneous adipose tissue (SAT) layer thickness and to understand the distribution of body fat. A device was designed to illuminate the body parts by near-infrared (NIR), measure the backscattered light, and predict the SAT layer thickness. The device was controlled by a single-chip microcontroller (SCM), and the thickness value was presented on a liquid crystal display (LCD). There were 30 subjects in this study, and the measurements were performed on 14 body parts for each subject. The paper investigated the impacts of pressure and skin colour on the measurement. Combining with principal component analysis (PCA) and support vector regression (SVR), the measurement accuracy of SAT layer thickness was 89.1 % with a mechanical caliper as reference. The measuring range was 5-11 mm. The study provides a non-invasive and low-cost technique to detect subcutaneous fat thickness, which is more accessible and affordable compared to other conventional techniques. The designed device can be used at home and in community.

  13. GMTNIRS (Giant Magellan Telescope near-infrared spectrograph): design concept

    NASA Astrophysics Data System (ADS)

    Lee, Sungho; Yuk, In-Soo; Lee, Hanshin; Wang, Weisong; Park, Chan; Park, Kwi-Jong; Chun, Moo-Young; Pak, Soojong; Strubhar, Joseph; Deen, Casey; Gully-Santiago, Michael; Rand, Jared; Seo, Haingja; Kwon, Jungmi; Oh, Heeyoung; Barnes, Stuart; Lacy, John; Goertz, John; Park, Won-Kee; Pyo, Tae-Soo; Jaffe, Daniel T.

    2010-07-01

    We are designing a sensitive high resolution (R=60,000-100,000) spectrograph for the Giant Magellan Telescope (GMTNIRS, the GMT Near-Infrared Spectrograph). Using large-format IR arrays and silicon immersion gratings, this instrument will cover all of the J (longer than 1.1 μm), H, and K atmospheric windows or all of the L and M windows in a single exposure. GMTNIRS makes use of the GMT adaptive optics system for all bands. The small slits will offer the possibility of spatially resolved spectroscopy as well as superior sensitivity and wavelength coverage. The GMTNIRS team is composed of scientists and engineers at the University of Texas, the Korea Astronomy and Space Science Institute, and Kyung Hee University. In this paper, we describe the optical and mechanical design of the instrument. The principal innovative feature of the design is the use of silicon immersion gratings which are now being produced by our team with sufficient quality to permit designs with high resolving power and broad instantaneous wavelength coverage across the near-IR.

  14. Prototype Nerve-Specific Near-Infrared Fluorophores

    PubMed Central

    Park, Min Ho; Hyun, Hoon; Ashitate, Yoshitomo; Wada, Hideyuki; Park, GwangLi; Lee, Jeong Heon; Njiojob, Costyl; Henary, Maged; Frangioni, John V.; Choi, Hak Soo

    2014-01-01

    Nerve preservation is an important issue during most surgery because accidental transection or injury results in significant morbidity, including numbness, pain, weakness, or paralysis. Currently, nerves are still identified only by gross appearance and anatomical location during surgery, without intraoperative image guidance. Near-infrared (NIR) fluorescent light, in the wavelength range of 650-900 nm, has the potential to provide high-resolution, high-sensitivity, and real-time avoidance of nerve damage, but only if nerve-specific NIR fluorophores can be developed. In this study, we evaluated a series of Oxazine derivatives to highlight various peripheral nerve structures in small and large animals. Among the targeted fluorophores, Oxazine 4 has peak emission near into the NIR, which provided nerve-targeted signal in the brachial plexus and sciatic nerve for up to 12 h after a single intravenous injection. In addition, recurrent laryngeal nerves were successfully identified and highlighted in real time in swine, which could be preserved during the course of thyroid resection. Although optical properties of these agents are not yet optimal, chemical structure analysis provides a basis for improving these prototype nerve-specific NIR fluorophores even further. PMID:24955143

  15. Textile integrated sensors and actuators for near-infrared spectroscopy.

    PubMed

    Zysset, Christoph; Nasseri, Nassim; Büthe, Lars; Münzenrieder, Niko; Kinkeldei, Thomas; Petti, Luisa; Kleiser, Stefan; Salvatore, Giovanni A; Wolf, Martin; Tröster, Gerhard

    2013-02-11

    Being the closest layer to our body, textiles provide an ideal platform for integrating sensors and actuators to monitor physiological signals. We used a woven textile to integrate photodiodes and light emitting diodes. LEDs and photodiodes enable near-infrared spectroscopy (NIRS) systems to monitor arterial oxygen saturation and oxygenated and deoxygenated hemoglobin in human tissue. Photodiodes and LEDs are mounted on flexible plastic strips with widths of 4 mm and 2 mm, respectively. The strips are woven during the textile fabrication process in weft direction and interconnected with copper wires with a diameter of 71 μm in warp direction. The sensor textile is applied to measure the pulse waves in the fingertip and the changes in oxygenated and deoxygenated hemoglobin during a venous occlusion at the calf. The system has a signal-to-noise ratio of more than 70 dB and a system drift of 0.37% ± 0.48%. The presented work demonstrates the feasibility of integrating photodiodes and LEDs into woven textiles, a step towards wearable health monitoring devices.

  16. Application of near infrared spectroscopy to predict plant diseases

    NASA Astrophysics Data System (ADS)

    Xu, Huirong; Ying, Yibin; Ye, Zunzhong

    2005-11-01

    The objectives of this study were to characterize leaf reflectance spectra of tomato leaves damaged by leaf miner and to determine those leaf reflectance wavelengths that were most responsive to plant damage caused by the pest. Near infrared (NIR) Spectral characteristics of single tomato leaves at various levels of infestation by the leaf miner, were measured and analyzed using a spectrometer. Tomato leaf damage was classified into five scales, i.e., 0 (no damage), 1 (light damaged), 2 (10-25% damaged), 3 (more than 25% damaged), and 4 (severe damaged), based on the scale of infestation displayed on the surfaces of plant parts. Spectral parameter such as reflectance sensitivity was used to find the optimal wavelengths to determining and evaluating the damage level. Results showed that there were significant differences in reflectance among infestations at wavelengths of 1450nm and 1900 nm particularly. The determining coefficients (R2) for a linear relationship were 0.98 and 0.91 for the spectral-infestation levels relations. Thus, both of these wavelengths were good indicators of leaf senescence caused by the leaf miner.

  17. Near infrared spectroscopy based brain-computer interface

    NASA Astrophysics Data System (ADS)

    Ranganatha, Sitaram; Hoshi, Yoko; Guan, Cuntai

    2005-04-01

    A brain-computer interface (BCI) provides users with an alternative output channel other than the normal output path of the brain. BCI is being given much attention recently as an alternate mode of communication and control for the disabled, such as patients suffering from Amyotrophic Lateral Sclerosis (ALS) or "locked-in". BCI may also find applications in military, education and entertainment. Most of the existing BCI systems which rely on the brain's electrical activity use scalp EEG signals. The scalp EEG is an inherently noisy and non-linear signal. The signal is detrimentally affected by various artifacts such as the EOG, EMG, ECG and so forth. EEG is cumbersome to use in practice, because of the need for applying conductive gel, and the need for the subject to be immobile. There is an urgent need for a more accessible interface that uses a more direct measure of cognitive function to control an output device. The optical response of Near Infrared Spectroscopy (NIRS) denoting brain activation can be used as an alternative to electrical signals, with the intention of developing a more practical and user-friendly BCI. In this paper, a new method of brain-computer interface (BCI) based on NIRS is proposed. Preliminary results of our experiments towards developing this system are reported.

  18. Near-infrared spectroscopy for burning plasma diagnostic applications.

    PubMed

    Soukhanovskii, V A

    2008-10-01

    Ultraviolet and visible (UV-VIS, 200-750 nm) atomic spectroscopy of neutral and ionized fuel species (H, D, T, and Li) and impurities (e.g., He, Be, C, and W) is a key element of plasma control and diagnosis on International Thermonuclear Experimental Reactor and future magnetically confined burning plasma experiments (BPXs). Spectroscopic diagnostic implementation and performance issues that arise in the BPX harsh nuclear environment in the UV-VIS range, e.g., degradation of first mirror reflectivity under charge-exchange atom bombardment (erosion) and impurity deposition, permanent and dynamic loss of window, and optical fiber transmission under intense neutron and gamma-ray fluxes, are either absent or not as severe in the near-infrared (NIR, 750-2000 nm) range. An initial survey of NIR diagnostic applications has been undertaken on the National Spherical Torus Experiment. It is demonstrated that NIR spectroscopy can be used for machine protection and plasma control applications, as well as contribute to plasma performance evaluation and physics studies. Emission intensity estimates demonstrate that NIR measurements are possible in the BPX plasma operating parameter range. Complications in the NIR range due to the parasitic background emissions are expected to occur at very high plasma densities, low impurity densities, and at high plasma-facing component temperatures.

  19. Motion in Jupiter's Atmospheric Vortices (Near-infrared filters)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Two frame 'movie' of a pair of vortices in Jupiter's southern hemisphere. The two frames are separated by ten hours. The right oval is rotating counterclockwise, like other anticyclonic bright vortices in Jupiter's atmosphere. The left vortex is a cyclonic (clockwise) vortex. The differences between them (their brightness, their symmetry, and their behavior) are clues to how Jupiter's atmosphere works. The frames span about fifteen degrees in latitude and longitude and are centered at 141 degrees west longitude and 36 degrees south planetocentric latitude. Both vortices are about 3500 kilometers in diameter in the north-south direction.

    The images were taken in near infrared light at 756 nanometers and show clouds that are at a pressure level of about 1 bar in Jupiter's atmosphere. North is at the top. The smallest resolved features are tens of kilometers in size. These images were taken on May 7, 1997, at a range of 1.5 million kilometers by the Solid State Imaging system on NASA's Galileo spacecraft.

    The Jet Propulsion Laboratory, Pasadena, CA manages the Galileo mission for NASA's Office of Space Science, Washington, DC. JPL is an operating division of California Institute of Technology (Caltech).

    This image and other images and data received from Galileo are posted on the World Wide Web, on the Galileo mission home page at URL http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at URL http://www.jpl.nasa.gov/galileo/sepo

  20. Fluorescence lifetime imaging with near-infrared dyes

    NASA Astrophysics Data System (ADS)

    Becker, Wolfgang; Shcheslavskiy, Vladislav

    2013-02-01

    Near-infrared (NIR) dyes are used as fluorescence markers in small-animal imaging and in diffuse optical tomography of the human brain. In these applications it is important to know whether the dyes bind to proteins or other tissue constituents, and whether their fluorescence lifetimes depend on the targets they are bound to. Unfortunately, neither the lasers nor the detectors of commonly used confocal and multiphoton laser scanning microscopes allow for excitation and detection of NIR fluorescence. We therefore upgraded existing confocal TCSPC FLIM systems with NIR lasers and NIR sensitive detectors. In multiphoton systems we used the Ti:Sa laser as a one-photon excitation source in combination with an NIR-sensitive detector in the confocal beam path. We tested a number of NIR dyes in biological tissue. Some of them showed clear lifetime changes depending on the tissue structures they are bound to. We therefore believe that NIR FLIM can deliver supplementary information on the tissue constitution and on local biochemical parameters.

  1. Novel near infrared sensors for hybrid BCI applications

    NASA Astrophysics Data System (ADS)

    Almajidy, Rand K.; Le, Khang S.; Hofmann, Ulrich G.

    2015-07-01

    This study's goal is to develop a low cost, portable, accurate and comfortable NIRS module that can be used simultaneously with EEG in a dual modality system for brain computer interface (BCI). The sensing modules consist of electroencephalography (EEG) electrodes (at the positions Fp1, Fpz and Fp2 in the international 10-20 system) with eight custom made functional near infrared spectroscopy (fNIRS) channels, positioned on the prefrontal cortex area with two extra channels to measure and eliminate extra-cranial oxygenation. The NIRS sensors were designed to guarantee good sensor-skin contact, without causing subject discomfort, using springs to press them to the skin instead of pressing them by cap fixture. Two open source software packages were modified to carry out dual modality hybrid BCI experiments. The experimental paradigm consisted of a mental task (arithmetic task or text reading) and a resting period. Both oxygenated hemoglobin concentration changes (HbO), and EEG signals showed an increase during the mental task, but the onset, period and amount of that increase depends on each modality's characteristics. The subject's degree of attention played an important role especially during online sessions. The sensors can be easily used to acquire brain signals from different cerebral cortex parts. The system serves as a simple technological test bed and will be used for stroke patient rehabilitation purposes.

  2. Retinal-Based Proton Pumping in the Near Infrared

    PubMed Central

    2017-01-01

    Proteorhodopsin (PR) and Gloeobacter rhodopsin (GR) are retinal-based light-driven proton pumps that absorb visible light (maxima at 520–540 nm). Shifting the action spectra of these proton pumps beyond 700 nm would generate new prospects in optogenetics, membrane sensor technology, and complementation of oxygenic phototrophy. We therefore investigated the effect of red-shifting analogues of retinal, combined with red-shifting mutations, on the spectral properties and pump activity of the resulting pigments. We investigated a variety of analogues, including many novel ones. One of the novel analogues we tested, 3-methylamino-16-nor-1,2,3,4-didehydroretinal (MMAR), produced exciting results. This analogue red-shifted all of the rhodopsin variants tested, accompanied by a strong broadening of the absorbance band, tailing out to 850–950 nm. In particular, MMAR showed a strong synergistic effect with the PR-D212N,F234S double mutant, inducing an astonishing 200 nm red shift in the absorbance maximum. To our knowledge, this is by far the largest red shift reported for any retinal protein. Very importantly, all MMAR-containing holoproteins are the first rhodopsins retaining significant pump activity under near-infrared illumination (730 nm light-emitting diode). Such MMAR-based rhodopsin variants present very promising opportunities for further synthetic biology modification and for a variety of biotechnological and biophysical applications. PMID:28094925

  3. Optical bench assembly for the near-infrared camera

    NASA Astrophysics Data System (ADS)

    Nordt, Alison; Edinger, Derek

    2005-08-01

    The Near Infrared Camera is the primary imaging instrument on the James Webb Space Telescope. This instrument operates in the wavelength range of 0.6 to 5 microns and at a temperature of 35K. Two mirror-image optical paths or modules are utilized to provide two adjacent fields of view for science observations and redundancy for the purpose of wavefront sensing. All optical components are supported and aligned by an Optical Bench Assembly consisting of two benches mounted back to back. Each optical bench is a closed back Beryllium structure optimized for mass and stiffness. The closed back structure is achieved by bonding two machined parts together at the midplane of the structure. Each bench half is an open back structure consisting of a facesheet with machined ribs optimized to provide stiffness and to support along primary load paths. The two benches are integrated with optical components separately and are subsequently joined by bolts and pins to form the Optical Bench Assembly. The assembly is then mounted to interface struts, which are used to mount the instrument within the Integrated Science Instrument Module for integration into the JWST observatory. The design of the Optical Bench Assembly is describing including trade studies and analysis results.

  4. Near-infrared free carrier absorption in heavily doped silicon

    SciTech Connect

    Baker-Finch, Simeon C.; McIntosh, Keith R.; Yan, Di; Fong, Kean Chern; Kho, Teng C.

    2014-08-14

    Free carrier absorption in heavily doped silicon can have a significant impact on devices operating in the infrared. In the near infrared, the free carrier absorption process can compete with band to band absorption processes, thereby reducing the number of available photons to optoelectronic devices such as solar cells. In this work, we fabricate 18 heavily doped regions by phosphorus and boron diffusion into planar polished silicon wafers; the simple sample structure facilitates accurate and precise measurement of the free carrier absorptance. We measure and model reflectance and transmittance dispersion to arrive at a parameterisation for the free carrier absorption coefficient that applies in the wavelength range between 1000 and 1500 nm, and the range of dopant densities between ∼10{sup 18} and 3 × 10{sup 20} cm{sup −3}. Our measurements indicate that previously published parameterisations underestimate the free carrier absorptance in phosphorus diffusions. On the other hand, published parameterisations are generally consistent with our measurements and model for boron diffusions. Our new model is the first to be assigned uncertainty and is well-suited to routine device analysis.

  5. LED-based near infrared sensor for cancer diagnostics

    NASA Astrophysics Data System (ADS)

    Bogomolov, Andrey; Ageev, Vladimir; Zabarylo, Urszula; Usenov, Iskander; Schulte, Franziska; Kirsanov, Dmitry; Belikova, Valeria; Minet, Olaf; Feliksberger, E.; Meshkovsky, I.; Artyushenko, Viacheslav

    2016-03-01

    Optical spectroscopic technologies are increasingly used for cancer diagnostics. Feasibility of differentiation between malignant and healthy samples of human kidney using Fluorescence, Raman, MIR and NIR spectroscopy has been recently reported . In the present work, a simplification of NIR spectroscopy method has been studied. Traditional high-resolution NIR spectrometry was replaced by an optical sensor based on a set of light-emitting diodes at selected wavelengths as light sources and a photodiode. Two prototypes of the sensor have been developed and tested using 14 in-vitro samples of seven kidney tumor patients. Statistical evaluation of results using principal component analysis and partial least-squares discriminant analysis has been performed. Despite only partial discrimination between tumor and healthy tissue achieved by the presented new technique, the results evidence benefits of LED-based near-infrared sensing used for oncological diagnostics. Publisher's Note: This paper, originally published on 4 March, 2016, was replaced with a corrected/revised version on 7 April, 2016. If you downloaded the original PDF but are unable to access the revision, please contact SPIE Digital Library Customer Service for assistance.

  6. Near-infrared absolute magnitudes of Type Ia Supernovae

    NASA Astrophysics Data System (ADS)

    Avelino, Arturo; Friedman, Andrew S.; Mandel, Kaisey; Kirshner, Robert; Challis, Peter

    2017-01-01

    Type Ia Supernovae light curves (SN Ia) in the near infrared (NIR) exhibit low dispersion in their peak luminosities and are less vulnerable to extinction by interstellar dust in their host galaxies. The increasing number of high quality NIR SNe Ia light curves, including the recent CfAIR2 sample obtained with PAIRITEL, provides updated evidence for their utility as standard candles for cosmology. Using NIR YJHKs light curves of ~150 nearby SNe Ia from the CfAIR2 and CSP samples, and from the literature, we determine the mean value and dispersion of the absolute magnitude in the range between -10 to 50 rest-frame days after the maximum luminosity in B band. We present the mean light-curve templates and Hubble diagram for YJHKs bands. This work contributes to a firm local anchor for supernova cosmology studies in the NIR which will help to reduce the systematic uncertainties due to host galaxy dust present in optical-only studies. This research is supported by NSF grants AST-156854, AST-1211196, Fundacion Mexico en Harvard, and CONACyT.

  7. Visible and near infrared fluorescence spectral flow cytometry.

    PubMed

    Nolan, John P; Condello, Danilo; Duggan, Erika; Naivar, Mark; Novo, David

    2013-03-01

    There is a long standing interest in measuring complete emission spectra from individual cells in flow cytometry. We have developed flow cytometry instruments and analysis approaches to enable this to be done routinely and robustly. Our spectral flow cytometers use a holographic grating to disperse light from single cells onto a CCD for high speed, wavelength-resolved detection. Customized software allows the single cell spectral data to be displayed and analyzed to produce new spectra-derived parameters. We show that familiar reference and calibration beads can be employed to quantitatively assess instrument performance. We use microspheres stained with six different quantum dots to compare a virtual bandpass filter approach with classic least squares (CLS) spectral unmixing, and then use antibody capture beads and CLS unmixing to demonstrate immunophenotyping of peripheral blood mononuclear cells using spectral flow cytometry. Finally, we characterize and evaluate several near infrared (NIR) emitting fluorophores for use in spectral flow cytometry. Spectral flow cytometry offers a number of attractive features for single cell analysis, including a simplified optical path, high spectral resolution, and streamlined approaches to quantitative multiparameter measurements. The availability of robust instrumentation, software, and analysis approaches will facilitate the development of spectral flow cytometry applications.

  8. Near-Infrared Grating Spectrometer for Mobile Phone Applications.

    PubMed

    Pügner, Tino; Knobbe, Jens; Grüger, Heinrich

    2016-05-01

    Near-infrared (NIR) spectroscopy is a well-established technique for the chemical analysis of organic and inorganic matter. Accordingly, spectroscopic instrumentation of different complexity has been developed and is currently commercially available. However, there are an increasing number of new mobile applications that have come into focus and that cannot be addressed by the existing technology due to size and cost. Therefore, a new miniaturized scanning grating spectrometer for NIR spectroscopy has been developed at Fraunhofer IPMS. It is based on micro-electro-mechanical systems (MEMS) technology, and has been designed to meet the requirements for mobile application, regarding spectral range, resolution, overall size, robustness, and cost. The MEMS spectrometer covers a spectral range from 950 nm to 1900 nm at a resolution of 10 nm. The instrument is extremely small and has a volume of only 2.1 cm(3) Therefore, it is well suited for integration, even into a mobile phone. A first sample of the new spectrometer has been manufactured and put into operation. The results of a series of test measurements are in good agreement with the requirements and specifications.

  9. Standardization of near infrared spectra measured on multi-instrument.

    PubMed

    Liu, Yan; Cai, Wensheng; Shao, Xueguang

    2014-07-11

    Calibration model transfer is essential for practical applications of near infrared (NIR) spectroscopy because the measurements of the spectra may be performed on different instruments and the difference between the instruments must be corrected. An approach for calibration transfer based on alternating trilinear decomposition (ATLD) algorithm is proposed in this work. From the three-way spectral matrix measured on different instruments, the relative intensity of concentration, spectrum and instrument is obtained using trilinear decomposition. Because the relative intensity of instrument is a reflection of the spectral difference between instruments, the spectra measured on different instruments can be standardized by a correction of the coefficients in the relative intensity. Two NIR datasets of corn and tobacco leaf samples measured with three instruments are used to test the performance of the method. The results show that, for both the datasets, the spectra measured on one instrument can be correctly predicted using the partial least squares (PLS) models built with the spectra measured on the other instruments.

  10. Near-infrared spectroscopy: a methodology-focused review.

    PubMed

    Pellicer, Adelina; Bravo, María del Carmen

    2011-02-01

    Near infrared spectroscopy (NIRS) is a light-based technology used to monitor tissue oxygen status. Refinements to the method since it was first described have extended its applicability to different research and clinical settings due to its non-invasiveness, instrument portability and ease of use. Classic NIRS recordings, based in the Beer-Lambert law, can be used for the trend monitoring of changes in tissue perfusion-oxygenation parting from an arbitrary zero point. However, in order to derive intermittently quantitative values in absolute terms, certain manoeuvres must be performed. More recently, the evolution of the technique has led to the development of instruments that provide an absolute value of regional hemoglobin saturation in a continuous manner. This review will focus on the physical principles of tissue spectroscopy including a brief description of the different operating principles that are currently in use or under development. The theoretical details, experimental procedures and data analysis involved in the measurements of physiological variables using NIRS will be described. The future beyond the scope of NIRS and potential lines of research will also be discussed.

  11. Moisture influence on near-infrared prediction of wheat hardness

    NASA Astrophysics Data System (ADS)

    Windham, William R.; Gaines, Charles S.; Leffler, Richard G.

    1991-02-01

    Recently near infrared (NTR) reflectance instrumentation has been used to provide an empirical measure of wheat hardness. This hardness scale is based on the radiation scattering properties of meal particles at 1680 and 2230 nm. Hard wheats have a larger mean particles size (PS) after grinding than soft wheats. However wheat kernel moisture content can influence mean PS after grinding. The objective of this study was to determine the sensitivity of MR wheat hardness measurements to moisture content and to make the hardness score independent of moisture by correcting hardness measurements for the actual moisture content of measured samples. Forty wheat cultivars composed of hard red winter hard red spring soft red winter and soft white winter were used. Wheat kernel subsamples were stored at 20 40 60 and 80 relative humidity (RH). After equilibration samples were ground and the meal analyzed for hardness score (HS) and moisture. HS were 48 50 54 and 65 for 20 40 60 and 80 RH respectively. Differences in HS within each wheat class were the result of a moisture induced change in the PS of the meal. An algorithm was developed to correct HS to 11 moisture. This correction provides HS that are nearly independent of moisture content. 1.

  12. Rapid Characterization of Tanshinone Extract Powder by Near Infrared Spectroscopy

    PubMed Central

    Luo, Gan; Xu, Bing; Shi, Xinyuan; Li, Jianyu; Dai, Shengyun; Qiao, Yanjiang

    2015-01-01

    Chemical and physical quality attributes of herbal extract powders play an important role in the research and development of Chinese medicine preparations. The active pharmaceutical ingredients have a direct impact on the herbal extract's efficacy, while the physical properties of raw material affect the pharmaceutical manufacturing process and the final products' quality. In this study, tanshinone extract powders from Salvia miltiorrhiza which are widely used for the treatment of cardiovascular diseases in the clinic are taken as the research object. Both the chemical information and physical information of tanshinone extract powders are analyzed by near infrared (NIR) spectroscopy. The partial least squares (PLS) and least square support vector machine (LS-SVM) models are investigated to build the relationship between NIR spectra and reference values. PLS models performed well for the content of crytotanshinone, tanshinone IIA, the moisture, and average median particle size, while, for specific surface area and tapped density, the LS-SVM models performed better than the PLS models. Results demonstrated NIR to be a valid and fast process analytical technology tool to simultaneously determine multiple quality attributes of herbal extract powders and indicated that there existed some nonlinear relationship between NIR spectra and physical quality attributes. PMID:25866511

  13. Constraining Type Ia Supernova Physics with Near-Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Sand, David; Valenti, Stefano; Howell, Andy; Graham, Melissa; Parrent, Jerod

    2014-02-01

    Despite their success as standardizable candles, relatively little is known about the exact progenitor(s) and explosion physics of type Ia supernovae -- a potential source of systematic uncertainty for future dark energy surveys, and a hole in our knowledge about stellar end-states. One promising route forward is the combination of dense optical time series and near-infrared (NIR) spectroscopic data sets. Recent work has suggested that the NIR can discern unburned carbon from the progenitor white dwarf more cleanly than in the optical, and its unique access to relatively unblended magnesium lines also probes the inner edge of carbon burning. Both measures provide a direct constraint for SN Ia explosion models, but only a handful of appropriate NIR spectroscopic time series exist. We propose to continue our campaign to roughly double the sample of SN Ia with such data (leveraging our access to a worldwide network of 1m imaging telescopes and twin robotic optical spectrographs) in order to begin to tackle our understanding of NIR spectral diagnostics and how they vary from supernova to supernova. Note that we were allocated time with Gemini South Flamingos-2 in 2013B, but have not triggered any ToO time yet, partially due to the persistent alignment issues with the On-Instrument Wave Front Sensor.

  14. Constraining Type Ia Supernova Physics with Near-Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Sand, David; Valenti, Stefano; Howell, Andy; Graham, Melissa; Parrent, Jerod

    2014-08-01

    Despite their success as standardizable candles, relatively little is known about the exact progenitor(s) and explosion physics of type Ia supernovae -- a potential source of systematic uncertainty for future dark energy surveys, and a hole in our knowledge about stellar end-states. One promising route forward is the combination of dense optical time series and near-infrared (NIR) spectroscopic data sets. Recent work has suggested that the NIR can discern unburned carbon from the progenitor white dwarf more cleanly than in the optical, and its unique access to relatively unblended magnesium lines also probes the inner edge of carbon burning. Both measures provide a direct constraint for SN Ia explosion models, but only a handful of appropriate NIR spectroscopic time series exist. We propose to continue our campaign to roughly double the sample of SN Ia with such data (leveraging our access to a worldwide network of 1m imaging telescopes and twin robotic optical spectrographs) in order to begin to tackle our understanding of NIR spectral diagnostics and how they vary from supernova to supernova. During our 2014A time thus far, we have been intensely following the nearest SN Ia in a generation -- SN 2014J -- and have already submitted our initial results.

  15. Quantitative analysis of ice films by near-infrared spectroscopy

    NASA Technical Reports Server (NTRS)

    Keiser, Joseph T.

    1990-01-01

    One of the outstanding problems in the Space Transportation System is the possibility of the ice buildup on the external fuel tank surface while it is mounted on the launch pad. During the T-2 hours (and holding) period, the frost/ice thickness on the external tank is monitored/measured. However, after the resumption of the countdown time, the tank surface can only be monitored remotely. Currently, remote sensing is done with a TV camera coupled to a thermal imaging device. This device is capable of identifying the presence of ice, especially if it is covered with a layer of frost. However, it has difficulty identifying transparent ice, and, it is not capable of determining the thickness of ice in any case. Thus, there is a need for developing a technique for measuring the thickness of frost/ice on the tank surface during this two hour period before launch. The external tank surface is flooded with sunlight (natural or simulated) before launch. It may be possible, therefore, to analyze the diffuse reflection of sunlight from the external tank to determine the presence and thickness of ice. The purpose was to investigate the feasibility of this approach. A near-infrared spectrophotometer was used to record spectra of ice. It was determined that the optimum frequencies for monitoring the ice films were 1.03 and 1.255 microns.

  16. Distributed Software for Observations in the Near Infrared

    NASA Astrophysics Data System (ADS)

    Gavryusev, V.; Baffa, C.; Giani, E.

    We have developed an integrated system that performs astronomical observations in Near Infrared bands operating two-dimensional instruments at the Italian National Infrared Facility's \\htmllink{ARNICA}{http://helios.arcetri.astro.it:/home/idefix/Mosaic/ instr/arnica/arnica.html} and \\htmllink{LONGSP}{http://helios.arcetri.astro.it:/home/idefix/Mosaic/ instr/longsp/longsp.html}. This software consists of several communicating processes, generally executed across a network, as well as on a single computer. The user interface is organized as widget-based X11 client. The interprocess communication is provided by sockets and uses TCP/IP. The processes denoted for control of hardware (telescope and other instruments) should be executed currently on a PC dedicated for this task under DESQview/X, while all other components (user interface, tools for the data analysis, etc.) can also work under UNIX\\@. The hardware independent part of software is based on the Athena Widget Set and is compiled by GNU C to provide maximum portability.

  17. Visible and Near Infrared Fluorescence Spectral Flow Cytometry

    PubMed Central

    Nolan, John P.; Condello, Danilo; Duggan, Erika; Naivar, Mark; Novo, David

    2013-01-01

    There is a long standing interest in measuring complete emission spectra from individual cells in flow cytometry. We have developed flow cytometry instruments and analysis approaches to enable this to be done routinely and robustly. Our spectral flow cytometers use a holographic grating to disperse light from single cells onto a CCD for high speed, wavelength-resolved detection. Customized software allows the single cell spectral data to be displayed and analyzed to produce new spectra-derived parameters. We show that familiar reference and calibration beads can be employed to quantitatively assess instrument performance. We use microspheres stained with six different quantum dots to compare a virtual bandpass filter approach with classic least squares (CLS) spectral unmixing, and then use antibody capture beads and CLS unmixing to demonstrate immunophenotyping of peripheral blood mononuclear cells using spectral flow cytometry. Finally, we characterize and evaluate several near infrared (NIR) emitting fluorophores for use in spectral flow cytometry. Spectral flow cytometry offers a number of attractive features for single cell analysis, including a simplified optical path, high spectral resolution, and streamlined approaches to quantitative multiparameter measurements. The availability of robust instrumentation, software, and analysis approaches will facilitate the development of spectral flow cytometry applications. PMID:23225549

  18. Human skin detection in the visible and near infrared.

    PubMed

    Mendenhall, Michael J; Nunez, Abel S; Martin, Richard K

    2015-12-10

    Skin detection is a well-studied area in color imagery and is useful in a number of scenarios to include search and rescue and computer vision. Most approaches focus on color imagery due to cost and availability. Many of the visible-based approaches do well at detecting skin (above 90%) but they tend to have relatively high false-alarm rates (8%-15%). This article presents a novel feature space for skin detection in visible and near infrared portions of the electromagnetic spectrum. The features are derived from known spectral absorption of skin constituents to include hemoglobin, melanin, and water as well as scattering properties of the dermis. Fitting a Gaussian mixture to skin and background distributions and using a likelihood ratio test detector, the features presented here show dominating performance when comparing receiver-operating characteristic curves (ROCs) and statistically significant improvement when comparing equal error rates and area under the ROC (AUC). A detection/false-alarm probability of 98.6%/1.1% is achieved for the averaged equal error rate (EER). EER values for the proposed feature space show a 5.6%-11.2% increase in detection probability with a 6.0%-11.6% decrease in false-alarm probability compared to well performing color-based features. The AUC shows a 0.034-0.173 increase in total area under the curve compared to well performing color-based features.

  19. Near infrared hyperspectral imaging for forensic analysis of document forgery.

    PubMed

    Silva, Carolina S; Pimentel, Maria Fernanda; Honorato, Ricardo S; Pasquini, Celio; Prats-Montalbán, José M; Ferrer, Alberto

    2014-10-21

    Hyperspectral images in the near infrared range (HSI-NIR) were evaluated as a nondestructive method to detect fraud in documents. Three different types of typical forgeries were simulated by (a) obliterating text, (b) adding text and (c) approaching the crossing lines problem. The simulated samples were imaged in the range of 928-2524 nm with spectral and spatial resolutions of 6.3 nm and 10 μm, respectively. After data pre-processing, different chemometric techniques were evaluated for each type of forgery. Principal component analysis (PCA) was performed to elucidate the first two types of adulteration, (a) and (b). Moreover, Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) was used in an attempt to improve the results of the type (a) obliteration and type (b) adding text problems. Finally, MCR-ALS and Partial Least Squares-Discriminant Analysis (PLS-DA), employed as a variable selection tool, were used to study the type (c) forgeries, i.e. crossing lines problem. Type (a) forgeries (obliterating text) were successfully identified in 43% of the samples using both the chemometric methods (PCA and MCR-ALS). Type (b) forgeries (adding text) were successfully identified in 82% of the samples using both the methods (PCA and MCR-ALS). Finally, type (c) forgeries (crossing lines) were successfully identified in 85% of the samples. The results demonstrate the potential of HSI-NIR associated with chemometric tools to support document forgery identification.

  20. Near-Infrared Grating Spectrometer for Mobile Phone Applications

    PubMed Central

    Knobbe, Jens; Grüger, Heinrich

    2016-01-01

    Near-infrared (NIR) spectroscopy is a well-established technique for the chemical analysis of organic and inorganic matter. Accordingly, spectroscopic instrumentation of different complexity has been developed and is currently commercially available. However, there are an increasing number of new mobile applications that have come into focus and that cannot be addressed by the existing technology due to size and cost. Therefore, a new miniaturized scanning grating spectrometer for NIR spectroscopy has been developed at Fraunhofer IPMS. It is based on micro–electro–mechanical systems (MEMS) technology, and has been designed to meet the requirements for mobile application, regarding spectral range, resolution, overall size, robustness, and cost. The MEMS spectrometer covers a spectral range from 950 nm to 1900 nm at a resolution of 10 nm. The instrument is extremely small and has a volume of only 2.1 cm3. Therefore, it is well suited for integration, even into a mobile phone. A first sample of the new spectrometer has been manufactured and put into operation. The results of a series of test measurements are in good agreement with the requirements and specifications. PMID:27170776

  1. Dynamic causal modelling for functional near-infrared spectroscopy

    PubMed Central

    Tak, S.; Kempny, A.M.; Friston, K.J.; Leff, A.P.; Penny, W.D.

    2015-01-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging technique for measuring changes in cerebral hemoglobin concentration via optical absorption changes. Although there is great interest in using fNIRS to study brain connectivity, current methods are unable to infer the directionality of neuronal connections. In this paper, we apply Dynamic Causal Modelling (DCM) to fNIRS data. Specifically, we present a generative model of how observed fNIRS data are caused by interactions among hidden neuronal states. Inversion of this generative model, using an established Bayesian framework (variational Laplace), then enables inference about changes in directed connectivity at the neuronal level. Using experimental data acquired during motor imagery and motor execution tasks, we show that directed (i.e., effective) connectivity from the supplementary motor area to the primary motor cortex is negatively modulated by motor imagery, and this suppressive influence causes reduced activity in the primary motor cortex during motor imagery. These results are consistent with findings of previous functional magnetic resonance imaging (fMRI) studies, suggesting that the proposed method enables one to infer directed interactions in the brain mediated by neuronal dynamics from measurements of optical density changes. PMID:25724757

  2. Broadband near-infrared metamaterial absorbers utilizing highly lossy metals

    NASA Astrophysics Data System (ADS)

    Ding, Fei; Dai, Jin; Chen, Yiting; Zhu, Jianfei; Jin, Yi; Bozhevolnyi, Sergey I.

    2016-12-01

    Radiation absorbers have increasingly been attracting attention as crucial components for controllable thermal emission, energy harvesting, modulators, etc. However, it is still challenging to realize thin absorbers which can operate over a wide spectrum range. Here, we propose and experimentally demonstrate thin, broadband, polarization-insensitive and omnidirectional absorbers working in the near-infrared range. We choose titanium (Ti) instead of the commonly used gold (Au) to construct nano-disk arrays on the top of a silicon dioxide (SiO2) coated Au substrate, with the quality (Q) factor of the localized surface plasmon (LSP) resonance being decreased due to the intrinsic high loss of Ti. The combination of this low-Q LSP resonance and the propagating surface plasmon (PSP) excitation resonance, which occur at different wavelengths, is the fundamental origin of the broadband absorption. The measured (at normal light incidence) absorption is over 90% in the wavelength range from 900 nm to 1825 nm, with high absorption persisting up to the incident angle of ~40°. The demonstrated thin-film absorber configuration is relatively easy to fabricate and can be realized with other properly selected materials.

  3. Development of a new diffuse near-infrared food measuring

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Piao, Renguan

    2006-11-01

    Industries from agriculture to petrochemistry have found near infrared (NIR) spectroscopic analysis useful for quality control and quantitative analysis of materials and products. The general chemical, polymer chemistry, petrochemistry, agriculture, food and textile industries are currently using NIR spectroscopic methods for analysis. In this study, we developed a new sort NIR instrument for food measuring. The instrument consists of a light source, 12 filters to the prismatic part. The special part is that we use a mirror to get two beams of light. And two PbS detectors were used. One detector collected the radiation of one light beam directly and the value was set as the standard instead the standard white surface. Another light beam irradiate the sample surface, and the diffuse light was collected by another detector. The value of the two detectors was compared and the absorbency was computed. We tested the performance of the NIR instrument in determining the protein and fat content of milk powder. The calibration showed the accuracy of the instrument in practice.

  4. Stratigraphy of snow profiles using near-infrared photography

    NASA Astrophysics Data System (ADS)

    Matzl, M.; Schneebeli, M.

    2002-12-01

    The detailed representation of the layers in snow profiles is extremly time consuming. Translucent profiles are used to reveal layer boundaries, however no method is known to relate the transmitted light intensity to morphologic parameters. We use digital near-infrared photography (NIP), centered at a wavelength of 890 nm, to determine optical grainsize on snow profiles. The reflectivity was calibrated with snow samples of different grain size and shape. The digital image of a snow profile is optically and geometrically corrected and the intensities are then converted to optical grainsize. The measured snow profiles on different slopes are compared to planar sections and classical snow profiles. In several cases the NIP image revealed thin layers, layer transitions and disturbances which are also visible in the planar section, but were not recorded in the snow profile. NIP profiles could be as large as 1 m high and 3 m long at very high spatial resolution by assembling several images. NIP of snow profiles is well suited to document and analyse snow stratigraphy and to determine optical diameter .

  5. The application of near infrared spectroscopy in nutritional intervention studies

    PubMed Central

    Jackson, Philippa A.; Kennedy, David O.

    2013-01-01

    Functional near infrared spectroscopy (NIRS) is a non-invasive optical imaging technique used to monitor cerebral blood flow (CBF) and by proxy neuronal activation. The use of NIRS in nutritional intervention studies is a relatively novel application of this technique, with only a small, but growing, number of trials published to date. These trials—in which the effects on CBF following administration of dietary components such as caffeine, polyphenols and omega-3 polyunsaturated fatty acids are assessed—have successfully demonstrated NIRS as a sensitive measure of change in hemodynamic response during cognitive tasks in both acute and chronic treatment intervention paradigms. The existent research in this area has been limited by the constraints of the technique itself however advancements in the measurement technology, paired with studies endeavoring increased sophistication in number and locations of channels over the head should render the use of NIRS in nutritional interventions particularly valuable in advancing our understanding of the effects of nutrients and dietary components on the brain. PMID:23964231

  6. SIMP: A Near-Infrared Proper Motion Survey

    NASA Astrophysics Data System (ADS)

    Artigau, Étienne; Lafrenière, David; Doyon, René; Albert, Loïc; Robert, Jasmin; Malo, Lison

    2009-02-01

    SIMP is a proper motion (PM) survey made with the Observatoire du Mont Mégantic (OMM) wide-field near-infrared camera CPAPIR at the CTIO 1.5 m and OMM 1.6 m telescopes. The SIMP observations were initiated in early 2005, are still ongoing and, to date, have covered 28% of the sky at high galactic latitudes. The PMs of the sources detected are determined by comparing their measured positions with those listed in the 2MASS point source catalog, giving a time baseline of 4 to 10 years. The 5 σ uncertainty on the relative SIMP and 2MASS astrometry is 1'', equivalent to a PM lower limit of 0.125-0.250''/yr, or a tangential velocity limit of 15-30 km/s at 25 pc. Up to the 2MASS magnitude limit (J~16.5), T dwarfs are found out to ~25 pc, while L dwarfs may be found as far as 100 pc away.

  7. Near-infrared autofluorescence for the detection of parathyroid glands

    NASA Astrophysics Data System (ADS)

    Paras, Constantine; Keller, Matthew; White, Lisa; Phay, John; Mahadevan-Jansen, Anita

    2011-06-01

    A major challenge in endocrine surgery is the intraoperative detection of parathyroid glands during both thyroidectomies and parathyroidectomies. Current localization techniques such as ultrasound and sestamibi scan are mostly preoperative and rely on an abnormal parathyroid for its detection. In this paper, we present near-infrared (NIR) autofluorescence as a nonintrusive, real-time, automated in vivo method for the detection of the parathyroid gland. A pilot in vivo study was conducted to assess the ability of NIR fluorescence to identify parathyroid glands during thyroid and parathyroidectomies. Fluorescence measurements at 785 nm excitation were obtained intra-operatively from the different tissues exposed in the neck region in 21 patients undergoing endocrine surgery. The fluorescence intensity of the parathyroid gland was found to be consistently greater than that of the thyroid and all other tissues in the neck of all patients. In particular, parathyroid fluorescence was two to eleven times higher than that of the thyroid tissues with peak fluorescence occurring at 820 to 830 nm. These results indicate that NIR fluorescence has the potential to be an excellent optical tool to locate parathyroid tissue during surgery.

  8. Application of functional near-infrared spectroscopy in psychiatry.

    PubMed

    Ehlis, Ann-Christine; Schneider, Sabrina; Dresler, Thomas; Fallgatter, Andreas J

    2014-01-15

    Two decades ago, the introduction of functional near-infrared spectroscopy (fNIRS) into the field of neuroscience created new opportunities for investigating neural processes within the human cerebral cortex. Since then, fNIRS has been increasingly used to conduct functional activation studies in different neuropsychiatric disorders, most prominently schizophrenic illnesses, affective disorders and developmental syndromes, such as attention-deficit/hyperactivity disorder as well as normal and pathological aging. This review article provides a comprehensive overview of state of the art fNIRS research in psychiatry covering a wide range of applications, including studies on the phenomenological characterization of psychiatric disorders, descriptions of life-time developmental aspects, treatment effects, and genetic influences on neuroimaging data. Finally, methodological shortcomings as well as current research perspectives and promising future applications of fNIRS in psychiatry are discussed. We conclude that fNIRS is a valid addition to the range of neuroscientific methods available to assess neural mechanisms underlying neuropsychiatric disorders. Future research should particularly focus on expanding the presently used activation paradigms and cortical regions of interest, while additionally fostering technical and methodological advances particularly concerning the identification and removal of extracranial influences on fNIRS data as well as systematic artifact correction. Eventually, fNIRS might be a useful tool in practical psychiatric settings involving both diagnostics and the complementary treatment of psychological disorders using, for example, neurofeedback applications.

  9. [Near infrared Raman spectra analysis of rhizoma dioscoreae].

    PubMed

    Lin, Wen-Shuo; Chen, Rong; Li, Yong-Zeng; Feng, Shang-Yuan; Huang, Zu-Fang; Xie, Bing-Xian

    2008-05-01

    A novel and compact near-infrared (NIR) Raman system was developed using 785 nm diode laser, volume-phase technology holographic system, and NIR intensified charge-coupled device (CCD). The Raman spectra and first derivative spectra of rhizoma dioscoreae were obtained. The Raman spectra of rhizoma dioscoreae showed three strong characteristic peaks at 477, 863 and 936 cm(-1), respectively. The major ingredients are protein, amino acid, starch, polysaccharides and so on, matching the known basic biochemical composition of rhizoma dioscoreae. In the first derivative spectra of rhizoma dioscoreae, the distinguishing characteristic peaks appeared at 467, 484, 870 and 943 cm(-1). Contrasted with rhizoma dioscoreae Raman spectra in the ranges of 600 to 800 cm(-1) and 1 000 to 1 400 cm(-1), the changes in rhizoma dioscoreae Raman first derivative spectra are represented more clearly than the rhizoma dioscoreae Raman spectra. So the rhizoma dioscoreae Raman first derivative spectra can be an accurate supplementary analysis method to the rhizoma dioscoreae Raman spectra.

  10. A novel storage method for near infrared spectroscopy chemometric models.

    PubMed

    Zhang, Zhi-Min; Chen, Shan; Liang, Yi-Zeng

    2010-06-04

    Chemometric Modeling Markup Language (CMML) is developed by us for containing chemometrics models within one document through converting binary data into strings by base64 encode/decode algorithms to solve the interoperability issue in sharing chemometrics models. It provides a base functionality for storage of sampling, variable selection, pretreating, outlier and modeling parameters and data. With the help of base64 algorithm, the usability of CMML is in equilibrium with size by transforming the binary data into base64 encoded string. Due to the advantages of Extensible Markup Language (XML), models stored in CMML can be easily reused in various other software and programming languages as long as the programming language has XML parsing library. One can also use the XML Path Language (XPath) query language to select desired data from the CMML file effectively. The application of this language in near infrared spectroscopy model storage is implemented as a class in C++ language and available as open source software (http://code.google.com/p/cmml), and the implementations in other languages, such as MATLAB and R are in progress.

  11. Keck Near-Infrared AO Observation of Io in 2011

    NASA Astrophysics Data System (ADS)

    Cantrall, C.; De Pater, I.; Nelson, D. M.; Williams, D. A.; de Kleer, K.

    2015-12-01

    We report observation and analysis of 23 distinct hot spots on Io from images taken in November of 2011 on the 10-m W.M. Keck II telescope. The observations were obtained with 8 different near-infrared (1-5 μm) filters, although no hot spots were detected at the smallest wavelength filters of Hc (1.58 μm) and Kc (2.27 μm). The radiant flux of each hot spot at the different wavelengths was found, which allowed for 1-T and 2-T blackbody fits to obtain estimates of the temperature, emission area, and subsequently, the total radiant output. Global maps over a cylindrical coordinate system were also constructed at each wavelength. In general, Io appeared to be fairly quiescent compared to datasets obtained between 2001 and 2010, with no significant outburst at any particular hot spot. Using GIS software it was possible to create surface maps that display the changes in some of the major hot spots observed between 2001 and 2011. The analysis of these maps and comparison to observations at different time periods will help to further construct a timeline of Io's volcanic activity, which will lead to a better understanding of the variations in surface heat flow over time, the global distribution of hot spots, and the style of eruptions.

  12. Near-infrared spectroscopy for burning plasma diagnostic applicationsa)

    NASA Astrophysics Data System (ADS)

    Soukhanovskii, V. A.

    2008-10-01

    Ultraviolet and visible (UV-VIS, 200-750nm) atomic spectroscopy of neutral and ionized fuel species (H, D, T, and Li) and impurities (e.g., He, Be, C, and W) is a key element of plasma control and diagnosis on International Thermonuclear Experimental Reactor and future magnetically confined burning plasma experiments (BPXs). Spectroscopic diagnostic implementation and performance issues that arise in the BPX harsh nuclear environment in the UV-VIS range, e.g., degradation of first mirror reflectivity under charge-exchange atom bombardment (erosion) and impurity deposition, permanent and dynamic loss of window, and optical fiber transmission under intense neutron and γ-ray fluxes, are either absent or not as severe in the near-infrared (NIR, 750-2000nm) range. An initial survey of NIR diagnostic applications has been undertaken on the National Spherical Torus Experiment. It is demonstrated that NIR spectroscopy can be used for machine protection and plasma control applications, as well as contribute to plasma performance evaluation and physics studies. Emission intensity estimates demonstrate that NIR measurements are possible in the BPX plasma operating parameter range. Complications in the NIR range due to the parasitic background emissions are expected to occur at very high plasma densities, low impurity densities, and at high plasma-facing component temperatures.

  13. Photochemical effects in the lens from near infrared radiation?

    NASA Astrophysics Data System (ADS)

    Söderberg, Per G.; Al-Saqry, Riyadh; Schulmeister, Karl; Gallichanin, Konstantin; Kronschläger, Martin; Yu, Zhaohua

    2009-02-01

    Conclusion: The current data are consistent with a potential photochemical effect of in vivo exposure of the crystalline lens to near infrared radiation since the onset of cataract after in just above threshold dose was at least 18 hrs delayed after the exposure. Materials and methods: The eyes of 6 weeks old Sprague-Dawley rats were exposed unilaterally in vivo to 1090 nm, 6.2 W quasi-top hat spatial distribution with a 3 mm spot on the anterior lens surface within the dilated pupil. First, four exposure time groups of rats were exposed to increasing exposure times. At 24 hrs after exposure, the difference of light scattering between the lenses from the same animal was measured. Then, based on the first experiment, four post-exposure time groups were exposed unilaterally in vivo to 8 s of 1090 nm, 6.2 W quasi-top hat spatial distribution with a 3 mm spot on the anterior lens surface within the dilated pupil. After, the intended post-exposure time, the difference of light scattering between the lenses from the same animal was measured. Results: A 3 mm spot of 6.2 W induces light scattering in the lens with exposures of at least 8 s. Further, after 8 s of 6.2 W within a 3 mm spot on the lens surface, the light scattering increase in the lens was delayed at least 18 hrs after the exposure.

  14. Simulation and measurement of transcranial near infrared light penetration

    NASA Astrophysics Data System (ADS)

    Yue, Lan; Monge, Manuel; Ozgur, Mehmet H.; Murphy, Kevin; Louie, Stan; Miller, Carol A.; Emami, Azita; Humayun, Mark S.

    2015-03-01

    We are studying the transmission of LED array-emitted near-infrared (NIR) light through human tissues. Herein, we simulated and measured transcranial NIR penetration in highly scattering human head tissues. Using finite element analysis, we simulated photon diffusion in a multilayered 3D human head model that consists of scalp, skull, cerebral spinal fluid, gray matter and white matter. The optical properties of each layer, namely scattering and absorption coefficient, correspond to the 850 nm NIR light. The geometry of the model is minimally modified from the IEEE standard and the multiple LED emitters in an array were evenly distributed on the scalp. Our results show that photon distribution produced by the array exhibits little variation at similar brain depth, suggesting that due to strong scattering effects of the tissues, discrete spatial arrangements of LED emitters in an array has the potential to create a quasi-radially symmetrical illumination field. Measurements on cadaveric human head tissues excised from occipital, parietal, frontal and temporal regions show that illumination with an 850 nm LED emitter rendered a photon flux that closely follows simulation results. In addition, prolonged illumination of LED emitted NIR showed minimal thermal effects on the brain.

  15. A NEAR-INFRARED SPECTROSCOPIC SURVEY OF K-SELECTED GALAXIES AT z{approx} 2.3: COMPARISON OF STELLAR POPULATION SYNTHESIS CODES AND CONSTRAINTS FROM THE REST-FRAME NIR

    SciTech Connect

    Muzzin, Adam; Marchesini, Danilo; Van Dokkum, Pieter G.; Labbe, Ivo; Kriek, Mariska; Franx, Marijn

    2009-08-20

    We present spectral energy distribution (SED) modeling of a sample of 34 K-selected galaxies at z{approx} 2.3. These galaxies have near-infrared (NIR) spectroscopy that samples the rest-frame Balmer/4000 A break as well as deep photometry in 13 broadband filters. New to our analysis is Infrared Array Camera (IRAC) data that extend the SEDs into the rest-frame NIR. Comparing parameters determined from SED fits with and without the IRAC data we find that the IRAC photometry significantly improves the confidence intervals of {tau}, A{sub v} , M {sub star}, and SFR for individual galaxies, but does not systematically alter the mean parameters of the sample. We use the IRAC data to assess how well current stellar population synthesis codes describe the rest-frame NIR SEDs of young galaxies where discrepancies between treatments of the thermally pulsating asymptotic giant branch phase of stellar evolution are most pronounced. The models of Bruzual and Charlot, Maraston, and Charlot and Bruzual all successfully reproduce the SEDs of our galaxies with {<=}5% differences in the quality of fit; however, the best-fit masses from each code differ systematically by as much as a factor of 1.5, and other parameters vary more, up to factors of 2-3. A comparison of best-fit stellar population parameters from different stellar population synthesis (SPS) codes, dust laws, and metallicities shows that the choice of SPS code is the largest systematic uncertainty in most parameters, and that systematic uncertainties are typically larger than the formal random uncertainties. The SED fitting confirms our previous result that galaxies with strongly suppressed SF account for {approx}50% of the K-bright population at z{approx} 2.3; however, the uncertainty in this fraction is large due to systematic differences in the specific star formation rates derived from the three SPS models.

  16. Near-infrared spectroscopy of candidate red supergiant stars in clusters

    NASA Astrophysics Data System (ADS)

    Messineo, Maria; Zhu, Qingfeng; Ivanov, Valentin D.; Figer, Donald F.; Davies, Ben; Menten, Karl M.; Kudritzki, Rolf P.; Chen, C.-H. Rosie

    2014-11-01

    Context. Clear identifications of Galactic young stellar clusters farther than a few kpc from the Sun are rare, despite the large number of candidate clusters. Aims: We aim to improve the selection of candidate clusters rich in massive stars with a multiwavelength analysis of photometric Galactic data that range from optical to mid-infrared wavelengths. Methods: We present a photometric and spectroscopic analysis of five candidate stellar clusters, which were selected as overdensities with bright stars (Ks< 7 mag) in GLIMPSE and 2MASS images. Results: A total of 48 infrared spectra were obtained. The combination of photometry and spectroscopy yielded six new red supergiant stars with masses from 10 M⊙ to 15 M⊙. Two red supergiants are located at Galactic coordinates (l,b) = (16.°7, -0.°63) and at a distance of about ~3.9 kpc; four other red supergiants are members of a cluster at Galactic coordinates (l,b) = (49.°3, + 0.°72) and at a distance of ~7.0 kpc. Conclusions: Spectroscopic analysis of the brightest stars of detected overdensities and studies of interstellar extinction along their line of sights are fundamental to distinguish regions of low extinction from actual stellar clusters. The census of young star clusters containing red supergiants is incomplete; in the existing all-sky near-infrared surveys, they can be identified as overdensities of bright stars with infrared color-magnitude diagrams characterized by gaps. Based on observations collected at the European Southern Observatory (ESO Programme 60.A-9700(E), and 089.D-0876), and on observations collected at the UKIRT telescope (programme ID H243NS).MM is currently employed by the MPIfR. Part of this work was performed at RIT (2009), at ESA (2010), and at the MPIfR.Tables 3, 4, and 6 are available in electronic form at http://www.aanda.org

  17. Post-maximum Near-infrared Spectra of SN 2014J: A Search for Interaction Signatures

    NASA Astrophysics Data System (ADS)

    Sand, D. J.; Hsiao, E. Y.; Banerjee, D. P. K.; Marion, G. H.; Diamond, T. R.; Joshi, V.; Parrent, J. T.; Phillips, M. M.; Stritzinger, M. D.; Venkataraman, V.

    2016-05-01

    We present near-infrared (NIR) spectroscopic and photometric observations of the nearby Type Ia SN 2014J. The 17 NIR spectra span epochs from +15.3 to +92.5 days after B-band maximum light, while the {{JHK}}s photometry include epochs from -10 to +71 days. These data are used to constrain the progenitor system of SN 2014J utilizing the Paβ line, following recent suggestions that this phase period and the NIR in particular are excellent for constraining the amount of swept-up hydrogen-rich material associated with a non-degenerate companion star. We find no evidence for Paβ emission lines in our post-maximum spectra, with a rough hydrogen mass limit of ≲ 0.1 M ⊙, which is consistent with previous limits in SN 2014J from late-time optical spectra of the Hα line. Nonetheless, the growing data set of high-quality NIR spectra holds the promise of very useful hydrogen constraints. Based on observations obtained at the Gemini Observatory under program GN-2014A-Q-8 (PI: Sand). Gemini is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), and Ministério da Ciência, Tecnologia e Inovação (Brazil).

  18. Near-infrared evidence for a sudden temperature increase in Eta Carinae

    NASA Astrophysics Data System (ADS)

    Mehner, Andrea; Ishibashi, Kazunori; Whitelock, Patricia; Nagayama, Takahiro; Feast, Michael; van Wyk, Francois; de Wit, Willem-Jan

    2014-04-01

    Aims: Eta Car's ultra-violet, optical, and X-ray light curves and its spectrum suggest a physical change in its stellar wind over the last decade. It has been proposed that the mass-loss rate has decreased by a factor of about 2 over the last 15 years. We complement these recent results by investigating the past evolution and the current state of η Car in the near-infrared (IR). Methods: We present JHKL photometry of η Car obtained at SAAO Sutherland from 2004-2013 with the Mk II photometer at the 0.75 m telescope and JHKs photometry with SIRIUS at the 1.4 m IRSF telescope from 2012-2013. The near-IR light curves since 1972 are analyzed. Results: The long-term brightening trends in η Car's JHKL light curves were discontinuous around the 1998 periastron passage. After 1998, the star shows excess emission above the extrapolated trend from earlier dates, especially in J and H, and the blueward, cyclical progression in its near-IR colors is accelerated. The near-IR color evolution is strongly correlated with the periastron passages. After correcting for the secular trend we find that the color evolution matches an apparent increase in blackbody temperature of an optically thick near-IR emitting plasma component from about 3500 K to 6000 K over the last 20 years. Conclusions: We suggest that the changing near-IR emission may be caused by variability in optically thick bremsstrahlung emission. Periastron passages play an important role in the observed excess near-IR emission after 1998 and the long-term color evolution. We thus propose the hypothesis that angular momentum transfer (via tidal acceleration) during periastron passages leads to sudden changes in η Car's atmosphere resulting in a long-term decrease in the mass-loss rate. Tables 1 and 2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/564/A14

  19. Enhanced near-infrared photoacoustic imaging of silica-coated rare-earth doped nanoparticles.

    PubMed

    Sheng, Yang; Liao, Lun-De; Bandla, Aishwarya; Liu, Yu-Hang; Yuan, Jun; Thakor, Nitish; Tan, Mei Chee

    2017-01-01

    Near-infrared photoacoustic (PA) imaging is an emerging diagnostic technology that utilizes the tissue transparent window to achieve improved contrast and spatial resolution for deep tissue imaging. In this study, we investigated the enhancement effect of the SiO2 shell on the PA property of our core/shell rare-earth nanoparticles (REs) consisting of an active rare-earth doped core of NaYF4:Yb,Er (REDNPs) and an undoped NaYF4 shell. We observed that the PA signal amplitude increased with SiO2 shell thickness. Although the SiO2 shell caused an observed decrease in the integrated fluorescence intensity due to the dilution effect, fluorescence quenching of the rare earth emitting ions within the REDNPs cores was successfully prevented by the undoped NaYF4 shell. Therefore, our multilayer structure consisting of an active core with successive functional layers was demonstrated to be an effective design for dual-modal fluorescence and PA imaging probes with improved PA property. The result from this work addresses a critical need for the development of dual-modal contrast agent that advances deep tissue imaging with high resolution and signal-to-noise ratio.

  20. Monitoring brain temperature by time-resolved near-infrared spectroscopy: pilot study

    NASA Astrophysics Data System (ADS)

    Bakhsheshi, Mohammad Fazel; Diop, Mamadou; St. Lawrence, Keith; Lee, Ting-Yim

    2014-05-01

    Mild hypothermia (HT) is an effective neuroprotective strategy for a variety of acute brain injuries. However, the wide clinical adaptation of HT has been hampered by the lack of a reliable noninvasive method for measuring brain temperature, since core measurements have been shown to not always reflect brain temperature. The goal of this work was to develop a noninvasive optical technique for measuring brain temperature that exploits both the temperature dependency of water absorption and the high concentration of water in brain (80%-90%). Specifically, we demonstrate the potential of time-resolved near-infrared spectroscopy (TR-NIRS) to measure temperature in tissue-mimicking phantoms (in vitro) and deep brain tissue (in vivo) during heating and cooling, respectively. For deep brain tissue temperature monitoring, experiments were conducted on newborn piglets wherein hypothermia was induced by gradual whole body cooling. Brain temperature was concomitantly measured by TR-NIRS and a thermocouple probe implanted in the brain. Our proposed TR-NIRS method was able to measure the temperature of tissue-mimicking phantoms and brain tissues with a correlation of 0.82 and 0.66 to temperature measured with a thermometer, respectively. The mean difference between the TR-NIRS and thermometer measurements was 0.15°C±1.1°C for the in vitro experiments and 0.5°C±1.6°C for the in vivo measurements.

  1. Near-infrared Circular and Linear Polarimetry of Monoceros R2

    NASA Astrophysics Data System (ADS)

    Kwon, Jungmi; Tamura, Motohide; Hough, James H.; Nagata, Tetsuya; Kusakabe, Nobuhiko

    2016-09-01

    We have conducted simultaneous JHK s -band imaging circular and linear polarimetry of the Monoceros R2 (Mon R2) cluster. We present results from deep and wide near-infrared linear polarimetry of the Mon R2 region. Prominent and extended polarized nebulosities over the Mon R2 field are revisited, and an infrared reflection nebula associated with the Mon R2 cluster and two local reflection nebulae, vdB 67 and vdB 69, is detected. We also present results from deep imaging circular polarimetry in the same region. For the first time, the observations show relatively high degrees of circular polarization (CP) in Mon R2, with as much as approximately 10% in the K s band. The maximum CP extent of a ring-like nebula around the Mon R2 cluster is approximately 0.60 pc, while that of a western nebula, around vdB 67, is approximately 0.24 pc. The extended size of the CP is larger than those seen in the Orion region around IRc2, while the maximum degree of CP of ∼10% is smaller than those of ∼17% seen in the Orion region. Nonetheless, both the CP size and degree of this region are among the largest in our infrared CP survey of star-forming regions. We have also investigated the time variability of the degree of the polarization of several infrared sources and found possible variations in three sources.

  2. Ultrafast fluorescence imaging in vivo with conjugated polymer fluorophores in the second near-infrared window

    NASA Astrophysics Data System (ADS)

    Hong, Guosong; Zou, Yingping; Antaris, Alexander L.; Diao, Shuo; Wu, Di; Cheng, Kai; Zhang, Xiaodong; Chen, Changxin; Liu, Bo; He, Yuehui; Wu, Justin Z.; Yuan, Jun; Zhang, Bo; Tao, Zhimin; Fukunaga, Chihiro; Dai, Hongjie

    2014-06-01

    In vivo fluorescence imaging in the second near-infrared window (1.0-1.7 μm) can afford deep tissue penetration and high spatial resolution, owing to the reduced scattering of long-wavelength photons. Here we synthesize a series of low-bandgap donor/acceptor copolymers with tunable emission wavelengths of 1,050-1,350 nm in this window. Non-covalent functionalization with phospholipid-polyethylene glycol results in water-soluble and biocompatible polymeric nanoparticles, allowing for live cell molecular imaging at >1,000 nm with polymer fluorophores for the first time. Importantly, the high quantum yield of the polymer allows for in vivo, deep-tissue and ultrafast imaging of mouse arterial blood flow with an unprecedented frame rate of >25 frames per second. The high time-resolution results in spatially and time resolved imaging of the blood flow pattern in cardiogram waveform over a single cardiac cycle (~200 ms) of a mouse, which has not been observed with fluorescence imaging in this window before.

  3. Near-infrared bioluminescent proteins for two-color multimodal imaging

    PubMed Central

    Rumyantsev, Konstantin A.; Turoverov, Konstantin K.; Verkhusha, Vladislav V.

    2016-01-01

    Bioluminescence imaging became a widely used technique for noninvasive study of biological processes in small animals. Bioluminescent probes with emission in near-infrared (NIR) spectral region confer the advantage of having deep tissue penetration capacity. However, there are a very limited number of currently available luciferases that exhibit NIR bioluminescence. Here, we engineered two novel chimeric probes based on RLuc8 luciferase fused with iRFP670 and iRFP720 NIR fluorescent proteins. Due to an intramolecular bioluminescence resonance energy transfer (BRET) between RLuc8 and iRFPs, the chimeric luciferases exhibit NIR bioluminescence with maxima at 670 nm and 720 nm, respectively. The 50 nm spectral shift between emissions of the two iRFP chimeras enables combined multicolor bioluminescence imaging (BLI) and the respective multicolor fluorescence imaging (FLI) of the iRFPs. We show that for subcutaneously implanted cells, NIR bioluminescence provided a 10-fold increase in sensitivity compared to NIR FLI. In deep tissues, NIR BLI enabled detection of as low as 104 cells. Both BLI and FLI allowed monitoring of tumor growth and metastasis from early to late stages. Multimodal imaging, which combines concurrent BLI and FLI, provides continuous spatiotemporal analysis of metastatic cells in animals, including their localization and quantification. PMID:27833162

  4. Reliability of Near-Infrared Spectroscopy for Determining Muscle Oxygen Saturation during Exercise

    ERIC Educational Resources Information Center

    Austin, Krista G.; Daigle, Karen A.; Patterson, Patricia; Cowman, Jason; Chelland, Sara; Haymes, Emily M.

    2005-01-01

    Near-infrared spectroscopy is currently used to assess changes in the oxygen saturation of the muscle during exercise. The primary purpose of this study was to assess the reliability of near-infrared spectroscopy in determining muscle oxygen saturation (StO[subscript 2]) in the vastus lateralis during cycling and the gastrocnemius during running…

  5. Manipulating pH using near-infrared light assisted by upconverting nanoparticles.

    PubMed

    Chen, Zhijun; Xiong, Yubing; Etchenique, Roberto; Wu, Si

    2016-11-29

    Near-infrared light can be used to manipulate the pH of aqueous solutions by using upconverting nanoparticle-assisted photocleavage of a ruthenium complex photobase. Upconverting nanoparticles and the photobase were also introduced into a pH-responsive hydrogel, in which near-infrared irradiation induced swelling of the hydrogel.

  6. Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus.

    PubMed

    Walther, L E; Asenov, D R; Di Martino, E

    2011-04-01

    Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.

  7. 21 CFR 882.1935 - Near Infrared (NIR) Brain Hematoma Detector.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Near Infrared (NIR) Brain Hematoma Detector. 882... Infrared (NIR) Brain Hematoma Detector. (a) Identification. A Near Infrared (NIR) Brain Hematoma Detector... evaluate suspected brain hematomas. (b) Classification. Class II (special controls). The special...

  8. 21 CFR 882.1935 - Near Infrared (NIR) Brain Hematoma Detector.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Near Infrared (NIR) Brain Hematoma Detector. 882... Infrared (NIR) Brain Hematoma Detector. (a) Identification. A Near Infrared (NIR) Brain Hematoma Detector... evaluate suspected brain hematomas. (b) Classification. Class II (special controls). The special...

  9. Near-infrared observations of the black hole transient GRS 1716-249.

    NASA Astrophysics Data System (ADS)

    Joshi, Vishal; Vadwale, Santosh; Ganesh, Shashikiran

    2017-03-01

    We report near-infrared photometric observations of GRS 1716-249 during the on-going outburst (ATel #9876, #9895, #10036, #10069). Observations were carried out on UT 20.99 March 2017 with the Mount Abu 1.2 meter telescope (+ PRL Near-Infrared Imager/Spectrograph).

  10. Near-Infrared Versus Mid-Infrared for the Quantitative and Qualitative Analysis of Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over several decades, near-infrared reflectance spectroscopy has been shown to be extremely versatile for the rapid analysis of many agricultural materials including forages, foods and grains. More recently, mid-infrared and near-infrared diffuse reflectance spectroscopy (DRIFTS and NIRS, respective...

  11. Detecting and Segregating Black Tip-Damaged Wheat Kernels Using Visible and Near Infrared Spectroscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Detection of individual wheat kernels with black tip symptom (BTS) and black tip damage (BTD) was demonstrated using near infrared reflectance spectroscopy (NIRS) and silicon light-emitting-diode (LED) based instruments. The two instruments tested, a single kernel near-infrared spectroscopy instrume...

  12. The near-infrared spectrum of ethynyl radical

    SciTech Connect

    Le, Anh T.; Hall, Gregory E.; Sears, Trevor J.

    2016-08-17

    We used transient diode laser absorption spectroscopy to measure three strong vibronic bands in the near infrared spectrum of the C2H, ethynyl, radical not previously observed in the gas phase. The radical was produced by ultraviolet excimer laser photolysis of either acetylene or (1,1,1)-trifluoropropyne in a slowly flowing sample of the precursor diluted in inert gas, and the spectral resolution was Doppler-limited. The character of the upper states was determined from the rotational and fine structure in the observed spectra and assigned by measurement of ground state rotational combination differences. The upper states include a 2Σ+ state at 6696 cm-1, a second 2Σ+ state at 7088 cm-1, and a 2Π state at 7110 cm-1. By comparison with published calculations [R. Tarroni and S. Carter, J. Chem. Phys 119, 12878 (2003); Mol. Phys. 102, 2167 (2004)], the vibronic character of these levels was also assigned. Moreover, the observed states contain both X 2Σ+ and A 2Π electronic characters. Several local rotational level perturbations were observed in the excited states. Kinetic measurements of the time-evolution of the ground state populations following collisional relaxation and reactive loss of the radicals formed in a hot, non-thermal, population distribution were made using some of the strong rotational lines observed. Finally, the case of C2H may be a good place to investigate the behavior at intermediate pressures of inert colliders, where the competition between relaxation and reaction can be tuned and observed to compare with master equation models, rather than deliberately suppressed to measure thermal rate constants.

  13. Evaluation of Phalaenopsis flowering quality using near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Suming; Chuang, Yung-Kun; Tsai, Chao-Yin; Chang, Yao-Chien A.; Yang, I.-Chang; Chang, Yung-Huei; Tai, Chu-Chun; Hou, Jiunn-Yan

    2013-05-01

    Carbohydrate contents have been demonstrated as indicators for flowering quality of Phalaenopsis plants. In this study, near infrared reflectance (NIR) spectroscopy was employed for quantitative analysis of carbohydrate contents like fructose, glucose, sucrose, and starch in Phalaenopsis. The modified partial least squares regression (MPLSR) method was adopted for spectra analyses of 176 grown plant samples (88 shoots and 88 roots), over the full wavelength range (FWR, 400 to 2498 nm). For fructose concentrations, the smoothing 1st derivative model can produce the best effect (Rc = 0.961, SEC = 0.210% DW, SEV = 0.324% DW) in the wavelength ranges of 1400-1600, 1800-2000, and 2200-2300 nm. For glucose concentrations, the smoothing 1st derivative model can produce the best effect (Rc = 0.975, SEC = 0.196% DW, SEV = 0.264% DW) in the wavelength range of 1400-1600, 1800-2000, and 2100-2400 nm. For sucrose concentrations, the smoothing 1st derivative model can produce the best effect (Rc = 0.961, SEC = 0.237% DW, SEV = 0.322% DW) in the wavelength range of 1300-1400, 1500-1800, 2000-2100, and 2200-2300 nm. For starch concentrations, the smoothing 1st derivative model can produce the best effect (Rc = 0.873, SEC = 0.697% DW, SEV = 0.774% DW) in the wavelength ranges of 500-700, 1200-1300, 1700-1800, and 2200-2300 nm. This study successfully developed the calibration models for inspecting concentrations of carbohydrates to predict the flowering quality in different cultivation environments of Phalaenopsis. The specific wavelengths can be used to predict the quality of Phalaenopsis flowers and thus to adjust cultivation managements.

  14. [Proximate analysis of straw by near infrared spectroscopy (NIRS)].

    PubMed

    Huang, Cai-jin; Han, Lu-jia; Liu, Xian; Yang, Zeng-ling

    2009-04-01

    Proximate analysis is one of the routine analysis procedures in utilization of straw for biomass energy use. The present paper studied the applicability of rapid proximate analysis of straw by near infrared spectroscopy (NIRS) technology, in which the authors constructed the first NIRS models to predict volatile matter and fixed carbon contents of straw. NIRS models were developed using Foss 6500 spectrometer with spectra in the range of 1,108-2,492 nm to predict the contents of moisture, ash, volatile matter and fixed carbon in the directly cut straw samples; to predict ash, volatile matter and fixed carbon in the dried milled straw samples. For the models based on directly cut straw samples, the determination coefficient of independent validation (R2v) and standard error of prediction (SEP) were 0.92% and 0.76% for moisture, 0.94% and 0.84% for ash, 0.88% and 0.82% for volatile matter, and 0.75% and 0.65% for fixed carbon, respectively. For the models based on dried milled straw samples, the determination coefficient of independent validation (R2v) and standard error of prediction (SEP) were 0.98% and 0.54% for ash, 0.95% and 0.57% for volatile matter, and 0.78% and 0.61% for fixed carbon, respectively. It was concluded that NIRS models can predict accurately as an alternative analysis method, therefore rapid and simultaneous analysis of multicomponents can be achieved by NIRS technology, decreasing the cost of proximate analysis for straw.

  15. Quantification of the extracerebral contamination of near infrared spectroscopy signals

    NASA Astrophysics Data System (ADS)

    Mudra, R.; Niederer, P.; Keller, E.

    2005-04-01

    Recently, conventional near infrared spectroscopy (NIRS) for oxymetry has been extended with an indocyanine green (ICG) dye dilution method which allows the estimation of cerebral blood flow (CBF) and cerebral blood volume (CBV). The signal obtained through the skull is substantially influenced by extracerebral tissue. In order to quantify and eliminate extracerebral contamination of the optical density signal we have applied two approaches. Firstly, we used spatially resolved spectroscopy (SRS) with a two receiver arrangement, with separations between emitter and two receivers in distances of d1=4.0cm and d2=6.5cm. The magnitude of the determined extracerebral contamination was verified with NIRS measurements in patients after brain herniation. Intracerebral circulatory arrest was confirmed by transcerebral Doppler examination. Secondly, Monte Carlo simulation was used to simulate the light propagation through the head to quantify the extracerebral contamination of the optical density signal of NIRS. The anatomical structure is determined from 3D-magnetic resonance imaging (MRI) using a voxel resolution of 0.8 x 0.8 x 0 .8 mm3 for three different pairs of T1/T2 values. We segment the MRI data to obtain a material matrix describing the composition of skin, skull, cerebral spinal fluid (CSF), grey and white matter. Each voxel in this material matrix characterizes the light absorption and dispersion coefficient of the identified material. This material matrix is applied in the Monte Carlo simulation. With SRS an extracerebral contamination of 65% of the optical density signal is extracted, while the Monte Carlo simulation results show that the extracerebral contamination decreases from 70% to 30% with increasing emitter-receiver distance. Differences between the NIRS ICG dye dilution technique and conventional NIRS oxymetry concerning the extracerebral contamination are discussed.

  16. Near Infrared Heptamethine Cyanine Dye-Mediated Cancer Imaging*

    PubMed Central

    Yang, Xiaojian; Shi, Chunmeng; Tong, Rong; Qian, Weiping; Zhau, Haiyen E.; Wang, Ruoxiang; Zhu, Guodong; Cheng, Jianjun; Yang, Vincent W.; Cheng, Tianmin; Henary, Maged; Strekowski, Lucjan; Chung, Leland W.K.

    2010-01-01

    Purpose Near-infrared (NIR) fluorescence imaging has great potential for noninvasive in vivo imaging of tumors. In this study, we demonstrate the preferential uptake and retention of two hepatamethine cyanine dyes, IR-783 and MHI-148, in tumor cells and tissues. Experimental Design IR-783 and MHI-148 were investigated for their ability to accumulate in human cancer cells, tumor xenografts and spontaneous mouse tumors in transgenic animals. Time- and concentration-dependent dye uptake and retention in normal and cancer cells and tissues were compared, and subcellular localization of the dyes and mechanisms of the dye uptake and retention in tumor cells were evaluated using organelle-specific tracking dyes and bromosulfophthalein (BSP), a competitive inhibitor of organic anion transporting peptides (OATPs). These dyes were used to detect human cancer metastases in a mouse model and differentiate cancer cells from normal cells in blood. Results These NIR hepatamethine cyanine dyes were retained in cancer cells but not normal cells, in tumor xenografts, and in spontaneous tumors in transgenic mice. They can be used to detect cancer metastasis and cancer cells in blood with a high degree of sensitivity. The dyes were found to concentrate in the mitochondria and lysosomes of cancer cells, probably through OATPs since the dye uptake and retention in cancer cells can be blocked completely by BSP. These dyes, when injected to mice, did not cause systemic toxicity. Conclusions These two heptamethine cyanine dyes are promising imaging agents for human cancers and can be further exploited to improve cancer detection, prognosis and treatment. PMID:20410058

  17. James Webb Telescope's Near Infrared Camera: Making Models, Building Understanding

    NASA Astrophysics Data System (ADS)

    Lebofsky, Larry A.; McCarthy, D. W.; Higgins, M. L.; Lebofsky, N. R.

    2010-10-01

    The Astronomy Camp for Girl Scout Leaders is a science education program sponsored by NASA's next large space telescope: The James Webb Space Telescope (JWST). The E/PO team for JWST's Near Infrared Camera (NIRCam), in collaboration with the Sahuaro Girl Scout Council, has developed a long-term relationship with adult leaders from all GSUSA Councils that directly benefits troops of all ages, not only in general science education but also specifically in the astronomical and technology concepts relating to JWST. We have been training and equipping these leaders so they can in turn teach young women essential concepts in astronomy, i.e., the night sky environment. We model what astronomers do by engaging trainers in the process of scientific inquiry, and we equip them to host troop-level astronomy-related activities. It is GSUSA's goal to foster girls’ interest and creativity in Science, Technology, Engineering, and Math, creating an environment that encourages their interests early in their lives while creating a safe place for girls to try and fail, and then try again and succeed. To date, we have trained over 158 leaders in 13 camps. These leaders have come from 24 states, DC, Guam, and Japan. While many of the camp activities are related to the "First Light” theme, many of the background activities relate to two of the other JWST and NIRCam themes: "Birth of Stars and Protoplanetary Systems” and "Planetary Systems and the Origin of Life.” The latter includes our own Solar System. Our poster will highlight the Planetary Systems theme: 1. Earth and Moon: Day and Night; Rotation and Revolution. 2. Earth/Moon Comparisons. 3. Size Model: The Diameters of the Planets. 4. Macramé Planetary (Solar) Distance Model. 5.What is a Planet? 6. Planet Sorting Cards. 7. Human Orrery 8. Lookback Time in Our Daily Lives NIRCam E/PO website: http://zeus.as.arizona.edu/ dmccarthy/GSUSA

  18. Development of silicon-germanium visible-near infrared arrays

    NASA Astrophysics Data System (ADS)

    Zeller, John W.; Rouse, Caitlin; Efstathiadis, Harry; Haldar, Pradeep; Lewis, Jay S.; Dhar, Nibir K.; Wijewarnasuriya, Priyalal; Puri, Yash R.; Sood, Ashok K.

    2016-05-01

    Photodetectors based on germanium which do not require cooling and can provide good near-infrared (NIR) detection performance offer a low-cost alternative to conventional infrared sensors based on material systems such as InGaAs, InSb, and HgCdTe. As a result of the significant difference in thermal expansion coefficients between germanium and silicon, tensile strain incorporated into Ge epitaxial layers deposited on Si utilizing specialized growth processes can extend the operational range of detection to 1600 nm and longer wavelengths. We have fabricated Ge based PIN photodetectors on 300 mm diameter Si wafers to take advantage of high throughput, large-area complementary metal-oxide semiconductor (CMOS) technology. This device fabrication process involves low temperature epitaxial deposition of Ge to form a thin p+ (boron) Ge seed/buffer layer, and subsequent higher temperature deposition of a thicker Ge intrinsic layer. This is followed by selective ion implantation of phosphorus of various concentrations to form n+ Ge regions, deposition of a passivating oxide cap, and then top copper contacts to complete the PIN detector devices. Various techniques including transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS) have been employed to characterize the material and structural properties of the epitaxially grown layers and fabricated detector devices, and these results are presented. The I-V response of the photodetector devices with and without illumination was also measured, for which the Ge based photodetectors consistently exhibited low dark currents of around ~1 nA at -1 V bias.

  19. Crosstalk study of near infrared InGaAs detectors

    NASA Astrophysics Data System (ADS)

    Li, Xue; Tang, Hengjing; Li, Tao; Fan, Cui; Shao, Xiumei; Li, Jianwei; Wei, Jun; Gong, Haimei

    2016-05-01

    Crosstalk characteristics of high density FPA detectors attract widespread attention in the application of electro-optical systems. Crosstalk characteristics of near-infrared (NIR) InGaAs photodiodes and focal plane arrays (FPAs) were studied in this paper. The mesa type detector was investigated by using laser beam induced current technique (LBIC) to measure the absorption outside the designed photosensitive area, and the results show that the excess absorption enlarges the crosstalk of the adjacent pixels. The structure optimization using the effective absorption layer between the pixels can effectively reduce the crosstalk to 2.5%. The major crosstalk components of the optimization photodiode come from the electronic signal caused by carrier lateral diffusion. For the planar type detectors, test structures were used to compare the crosstalk of different structures, and the guard ring structure shows good suppression of the crosstalk. Then the back-illuminated 32x32 InGaAs photodiodes with 30μm pitch were designed, and LBIC was used to measure its lateral diffusion of the effective carriers and fill factor of photosensitive area. The results indicate that the fill factor of detectors can reach up to 98% when the diffusion region is optimized, and the minimum response exists between two neighborhood pixels. Based on these crosstalk measurement results and optimizing structure designs, the linear InGaAs photodiodes were designed and thus the InGaAs FPA assembly was fabricated. The assembly shows higher electro-optical performance and good improvement on crosstalk. The assembly was applied in infrared imaging system and modulation transfer function (MTF) of FPA assembly was calculated to be above 0.50. The clear image based on FPA assembly was obtained.

  20. Near-infrared spectra of the uranian ring system

    NASA Astrophysics Data System (ADS)

    de Kleer, Katherine; de Pater, Imke; Ádámkovics, Máté; Hammel, Heidi

    2013-09-01

    We present the first high-resolution near-infrared (1.18-2.38 μm) spectrum of the rings of Uranus, as observed with adaptive optics on the W.M. Keck II telescope in August 2010. We derive ring equivalent widths, as well as ring and particle reflectivities for the ɛ ring and ringlet groups based on H- and K-band data. We find the rings to be gray, indicating that they are dominated by large particles rather than dust, and we find no evidence for water ice. We present a reflectivity spectrum for the ɛ ring alone, which we also find to be consistent with a flat spectrum. We derive H-band ring particle reflectivities of 0.022 ± 0.010, 0.051 ± 0.009 0.042 ± 0.012, and 0.043 ± 0.001 and K-band ring particle reflectivities of 0.016 ± 0.010, 0.034 ± 0.012, 0.047 ± 0.008 and 0.041 ± 0.002 for the 456, αβ, ηγδ, and ɛ ring groups. Previous observations have found ring particle reflectivities in the 0.033-0.044 range (de Pater, I., Gibbard, S., Macintosh, B.A., Roe, H.G. [2002]. Icarus 160, 359-374; Gibbard, S.G., de Pater, I., Hammel, H.B. [2005]. Icarus 174, 253-262), and are generally consistent with our results.

  1. Implanted near-infrared spectroscopy for cardiac monitoring

    NASA Astrophysics Data System (ADS)

    Bhunia, Sourav K.; Cinbis, Can

    2011-02-01

    Implanted Cardioverter Defibrillator (ICD) provides one of the most effective therapies for the prevention of sudden cardiac death, but also delivers some high voltage shocks inappropriately, causing morbidity and mortality. Implanted near-infrared spectroscopy (NIRS) may augment ICD arrhythmia detection by monitoring skeletal muscle perfusion. A two-wavelength, single-distance, continuous-wave implanted NIRS has been evaluated in-vivo. A weighted difference of the changes in attenuation at two wavelengths, across the isobestic point of the hemoglobin spectra, was taken to be the microvascular oxygenation trend indicator (O2 Index). Although the exact weight depends on the local vascular distribution and their oxygen levels, the hypothesis that a constant weight may be adequate for hemodynamic trending during short arrhythmic episodes, was tested. The sensor was implanted subcutaneously both on fresh tissue and inside scar tissue that formed around a pre-existing implant, in 3 animals each. Attenuations were recorded at 660 and 890 nm during normal sinus rhythm (NSR) and induced ventricular fibrillation (VF). The slope of the O2 Index over 10 seconds was computed for 7 NSR and 8 VF episodes in fresh and 13 NSR and 15 VF episodes in scar tissue pockets. The mean O2 Index slope was significantly different (p<0.0001) between NSR and VF rhythms for both the fresh and scar tissue pockets. Therefore implanted NIRS may be useful for preventing inappropriate detection of VF during electromagnetic interference, double counting of ECG T-wave as an R-wave, ICD lead failure, electrocardiographic aberrancy etc.

  2. Raman Database Considerations for Near-Infrared Systems

    SciTech Connect

    Kunkel, Brenda M.; Su, Yin-Fong; Tonkyn, Russell G.; Stephan, Eric G.; Joly, Alan G.; Birnbaum, Jerome C.; Jarman, Kristin H.; Johnson, Timothy J.

    2011-12-21

    For Raman spectroscopy the ability to detect is often limited by the existence and quality of the reference library to which field spectra are compared. Developing such databases is often labor- and resource-intensive; typically the generated data are not transferred to other instruments. Still other considerations may exist for comparing data at visible and ultraviolet excitation wavelengths such as resonance enhancement. However, for the common near-infrared wavelengths of 785, 830, 960, 1047 and 1064 nm where this is normally of a lesser concern, it is logical to consider whether data can be ported from one spectrometer to another so as to obviate the expensive and time-consuming process of generating reference data for each system. The present experiment generated a list of 125 chemical and common substances and formed a database from their corresponding 1064 nm spectra. The same molecules were then measured using a 785 nm system the new spectra were treated as “unknowns” and compared to the 1064 nm database using a commercial search algorithm. We found that at least 108 of the 125 spectra recorded at 785 nm were correctly identified using the search algorithm. For the few that were incorrectly identified, in most cases the spectra were extremely similar or the 785 nm signal was degraded due to fluorescence, as would occur regardless of reference data. Our results indicate that if the spectrometers are properly calibrated on both their wavelength and intensity axes, “foreign” data recorded at a different NIR wavelength can be successfully used as reference libraries

  3. Near-Infrared Observations of Compact Binary Systems

    NASA Astrophysics Data System (ADS)

    Khargharia, Juthika

    Low mass X-ray binaries (LMXBs) are a subset of compact binary systems in which a main-sequence or slightly evolved star fills its Roche lobe and donates mass to a neutron star or a black hole (BH) via an accretion disk. Robust estimates of compact object masses in these systems are required to enhance our current understanding of the physics of compact object formation, accretion disks and jets. Compact object masses are typically determined at near-infrared (NIR) wavelengths when the system is in quiescence and the donor star is the dominant source of flux. Previous studies have assumed that any non-stellar contribution at these wavelengths is minimal. However, this assumption is rarely true. By performing NIR spectroscopy, we determined the fractional donor star contribution to the NIR flux and the compact object masses in two LMXBs: V404 Cyg and Cen X-4. In our analysis, it was assumed that the light curve morphology remains consistent throughout quiescence. It has now been shown in several systems that veiling measurements from non-stellar sources are meaningful only if acquired contemporaneously with light curve measurements. We accounted for this in the measurement of the BH mass in the LMXB, XTE J1118+480. LMXBs are also considered to be the most likely candidates responsible for the formation of milli-second pulsars (MSP). Here, I present the unique case of PSR J1903+0327 that challenges this currently accepted theory of MSP formation and is a potential candidate for testing General Relativity. Observations in the NIR come with their own set of challenges. NIR detector arrays used in these observations generally have high dark current and readout noise. In an effort to lower the read noise in NICFPS at APO, we present a study done on the Hawaii-1RG engineering grade chip that served as a test bed for reducing the read noise in NICFPS.

  4. Fetal oxygenation measurement using wireless near infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Macnab, Andrew; Shadgan, Babak; Janssen, Patricia; Rurak, Dan

    2012-03-01

    Background: Fetal well-being is determined in large part by how well the placenta is able to supply oxygen and nutrients, but current technology is unable to directly measure how well a placenta functions. Near-infrared spectroscopy (NIRS) utilizes optical methods to measure tissue oxygenation. This pilot project evaluated the feasibility of NIRS for fetal monitoring through the maternal abdominal wall using a sheep model. Methods: A miniature wireless 2-wavelength NIRS device was placed on the abdominal skin over the placenta of a pregnant ewe whose fetus had been chronically catheterized to allow arterial sampling for measurement of arterial oxygen saturation. The NIRS device has 3-paired light emitting diodes and a single photodiode detector; allowing measurement of an index of tissue oxygen saturation (TSI%). Fetal limb TSI% values were compared before and during fetal breathing movements. Correlation was made during these events between arterial values and placental TSI% monitored continuously in real time. Results: Serial measurements were obtained in a single experiment. The correlation between transcutaneous NIRS derived TSI% and direct arterial oxygen saturation was very high (R2=0.86). Measures of fetal limb TSI% were declined after episodes of fetal breathing (P<0.005). Conclusions: This correlation suggests that NIRS is sensitive enough to detect changes in fetal tissue oxygenation noninvasively through the maternal abdominal wall in real-time in a sheep model. NIRS data confirmed that fetal breathing movements decrease arterial oxygen saturation in fetal lambs. If validated by further study this optical methodology could be applied as means of monitoring fetal wellbeing in humans.

  5. Effect of Mechanical Optical Clearing on Near-infrared Spectroscopy

    PubMed Central

    Idelson, Christopher R.; Vogt, William C.; King-Casas, Brooks; LaConte, Stephen M.; Rylander, Christopher G.

    2015-01-01

    Near-infrared Spectroscopy (NIRS) is a broadly utilized technology with many emerging applications including clinical diagnostics, sports medicine, and functional neuroimaging, to name a few. For functional brain imaging NIR light is delivered at multiple wavelengths through the scalp and skull to the brain to enable spatial oximetry measurements. Dynamic changes in brain oxygenation are highly correlated with neural stimulation, activation, and function. Unfortunately, NIRS is currently limited by its low spatial resolution, shallow penetration depth, and, perhaps most importantly, signal corruption due to light interactions with superficial non-target tissues such as scalp and skull. In response to these issues, we have combined the non-invasive and rapidly reversible method of mechanical tissue optical clearing (MOC) with a commercially available NIRS system. MOC utilizes a compressive loading force on tissue, causing the lateral displacement of blood and water, while simultaneously thinning the tissue. A MOC-NIRS Breath Hold Test displayed a ∼3.5 fold decrease in the time-averaged standard deviation between channels, consequentially promoting greater channel agreement. A Skin Pinch Test was implemented to negate brain and muscle activity from affecting the recorded signal. These results displayed a 2.5-3.0 fold increase in raw signal amplitude. Existing NIRS instrumentation has been further integrated within a custom helmet device to provide a uniform force distribution across the NIRS sensor array. These results showed a gradual decrease in time-averaged standard deviation among channels with an increase in applied pressure. Through these experiments, and the development of the MOC-NIRS helmet device, MOC appears to provide enhancement of NIRS technology beyond its current limitations. PMID:26041069

  6. The near-infrared spectrum of ethynyl radical

    DOE PAGES

    Le, Anh T.; Hall, Gregory E.; Sears, Trevor J.

    2016-08-17

    We used transient diode laser absorption spectroscopy to measure three strong vibronic bands in the near infrared spectrum of the C2H, ethynyl, radical not previously observed in the gas phase. The radical was produced by ultraviolet excimer laser photolysis of either acetylene or (1,1,1)-trifluoropropyne in a slowly flowing sample of the precursor diluted in inert gas, and the spectral resolution was Doppler-limited. The character of the upper states was determined from the rotational and fine structure in the observed spectra and assigned by measurement of ground state rotational combination differences. The upper states include a 2Σ+ state at 6696 cm-1,more » a second 2Σ+ state at 7088 cm-1, and a 2Π state at 7110 cm-1. By comparison with published calculations [R. Tarroni and S. Carter, J. Chem. Phys 119, 12878 (2003); Mol. Phys. 102, 2167 (2004)], the vibronic character of these levels was also assigned. Moreover, the observed states contain both X 2Σ+ and A 2Π electronic characters. Several local rotational level perturbations were observed in the excited states. Kinetic measurements of the time-evolution of the ground state populations following collisional relaxation and reactive loss of the radicals formed in a hot, non-thermal, population distribution were made using some of the strong rotational lines observed. Finally, the case of C2H may be a good place to investigate the behavior at intermediate pressures of inert colliders, where the competition between relaxation and reaction can be tuned and observed to compare with master equation models, rather than deliberately suppressed to measure thermal rate constants.« less

  7. Augmented microscopy with near-infrared fluorescence detection

    NASA Astrophysics Data System (ADS)

    Watson, Jeffrey R.; Martirosyan, Nikolay; Skoch, Jesse; Lemole, G. Michael; Anton, Rein; Romanowski, Marek

    2015-03-01

    Near-infrared (NIR) fluorescence has become a frequently used intraoperative technique for image-guided surgical interventions. In procedures such as cerebral angiography, surgeons use the optical surgical microscope for the color view of the surgical field, and then switch to an electronic display for the NIR fluorescence images. However, the lack of stereoscopic, real-time, and on-site coregistration adds time and uncertainty to image-guided surgical procedures. To address these limitations, we developed the augmented microscope, whereby the electronically processed NIR fluorescence image is overlaid with the anatomical optical image in real-time within the optical path of the microscope. In vitro, the augmented microscope can detect and display indocyanine green (ICG) concentrations down to 94.5 nM, overlaid with the anatomical color image. We prepared polyacrylamide tissue phantoms with embedded polystyrene beads, yielding scattering properties similar to brain matter. In this model, 194 μM solution of ICG was detectable up to depths of 5 mm. ICG angiography was then performed in anesthetized rats. A dynamic process of ICG distribution in the vascular system overlaid with anatomical color images was observed and recorded. In summary, the augmented microscope demonstrates NIR fluorescence detection with superior real-time coregistration displayed within the ocular of the stereomicroscope. In comparison to other techniques, the augmented microscope retains full stereoscopic vision and optical controls including magnification and focus, camera capture, and multiuser access. Augmented microscopy may find application in surgeries where the use of traditional microscopes can be enhanced by contrast agents and image guided delivery of therapeutics, including oncology, neurosurgery, and ophthalmology.

  8. PRAXIS: a near infrared spectrograph optimised for OH suppression

    NASA Astrophysics Data System (ADS)

    Ellis, S. C.; Bauer, S.; Bland-Hawthorn, J.; Case, S.; Content, R.; Fechner, T.; Giannone, D.; Haynes, R.; Hernandez, E.; Horton, A. J.; Klauser, U.; Lawrence, J. S.; Leon-Saval, S. G.; Lindley, E.; Löhmannsröben, H.-G.; Min, S.-S.; Pai, N.; Roth, M.; Shortridge, K.; Staszak, Nicholas F.; Tims, Julia; Xavier, Pascal; Zhelem, Ross

    2016-08-01

    Atmospheric emission from OH molecules is a long standing problem for near-infrared astronomy. PRAXIS is a unique spectrograph, currently in the build-phase, which is fed by a fibre array that removes the OH background. The OH suppression is achieved with fibre Bragg gratings, which were tested successfully on the GNOSIS instrument. PRAXIS will use the same fibre Bragg gratings as GNOSIS in the first implementation, and new, less expensive and more efficient, multicore fibre Bragg gratings in the second implementation. The OH lines are suppressed by a factor of 1000, and the expected increase in the signal-to-noise in the interline regions compared to GNOSIS is a factor of 9 with the GNOSIS gratings and a factor of 17 with the new gratings. PRAXIS will enable the full exploitation of OH suppression for the first time, which was not achieved by GNOSIS due to high thermal emission, low spectrograph transmission, and detector noise. PRAXIS will have extremely low thermal emission, through the cooling of all significantly emitting parts, including the fore-optics, the fibre Bragg gratings, a long length of fibre, and a fibre slit, and an optical design that minimises leaks of thermal emission from outside the spectrograph. PRAXIS will achieve low detector noise through the use of a Hawaii-2RG detector, and a high throughput through an efficient VPH based spectrograph. The scientific aims of the instrument are to determine the absolute level of the interline continuum and to enable observations of individual objects via an IFU. PRAXIS will first be installed on the AAT, then later on an 8m class telescope.

  9. Visible-Near Infrared Imaging Spectrometer Data of Explosion Craters

    NASA Technical Reports Server (NTRS)

    Farr, T. G.

    2005-01-01

    In a continuing study to capture a realistic terrain applicable to studies of cratering processes and landing hazards on Mars, we have obtained new high resolution visible-near infrared images of several explosion craters at the Nevada Test Site. We used the Airborne Visible-Infrared Imaging Spectrometer (AVIRIS) to obtain images in 224 spectral bands from 0.4-2.5 microns [1]. The main craters that were imaged were Sedan, Scooter, Schooner, Buggy, and Danny Boy [2]. The 390 m diameter Sedan crater, located on Yucca Flat, is the largest and freshest explosion crater on Earth that was formed under conditions similar to hypervelocity impact cratering. As such, it is effectively pristine, having been formed in 1962 as a result of the detonation of a 104 kiloton thermonuclear device, buried at the appropriate equivalent depth of burst required to make a "simple" crater [2]. Sedan was formed in alluvium of mixed lithology [3] and subsequently studied using a variety of field-based methods. Nearby secondary craters were also formed at the time and were also imaged by AVIRIS. Adjacent to Sedan and also in alluvium is Scooter, about 90 m in diameter and formed by a high-explosive event. Schooner (240 m) and Danny Boy (80 m, Fig. 1) craters were also important targets for AVIRIS as they were excavated in hard welded tuff and basaltic andesite, respectively [3, 4]. This variation in targets will allow the study of ejecta patterns, compositional modifications due to the explosions, and the role of craters as subsurface probes.

  10. Rapid defect detections of bonded wafer using near infrared polariscope

    NASA Astrophysics Data System (ADS)

    Ng, Chi Seng; Asundi, Anand K.

    2011-10-01

    In modern field of microelectronics and MEMS, wafer bonding has emerged as an important processing step in wide range of manufacturing applications. During the manufacturing process, even in the modern clean room, small defects result from trapped particles and gas bubbles exist at bonded interface. Defects and trapped particles may exist on the top and bottom of the wafers, or at the interface of bonded wafer pair. These inclusions will generate high stress around debond region at the wafers bonded interface. In this paper, inspection at the bonded interface will be the interest of investigation. Since silicon wafer is opaque to visible light, defect detection at the bonded interface of silicon wafer is not possible. Due to the fact that silicon wafer is transparent to wavelength greater than 1150nm, an Near Infrared Polariscope which has showed some promises on residual stress measurement on silicon devices has been adapted and developed. This method is based on the well known photoelastic principles, where the stress variations are measured based on the changes of light propagation velocity in birefringence material. The results are compared and contrast with conventional Infrared Transmission Imaging tool (IRT) which is widely used to inspect the bonded silicon wafer. In this research, the trapped particles that are not visible via conventional infrared transmission method are identified via the generated residual stress pattern. The magnitude of the residual stress fields associated with each defect is examined qualitatively and quantitatively. The stress field generated at the wafers bonded interface will looks like a 'butterfly' pattern. Wafer pairs Pyrex-Si and Si-Si bonded interface will be examined.

  11. Near-Infrared Lasing from Small-Molecule Organic Hemispheres.

    PubMed

    Wang, Xuedong; Liao, Qing; Li, Hui; Bai, Shuming; Wu, Yishi; Lu, Xiaomei; Hu, Huaiyuan; Shi, Qiang; Fu, Hongbing

    2015-07-29

    Near-infrared (NIR) lasers are key components for applications, such as telecommunication, spectroscopy, display, and biomedical tissue imaging. Inorganic III-V semiconductor (GaAs) NIR lasers have achieved great successes but require expensive and sophisticated device fabrication techniques. Organic semiconductors exhibit chemically tunable optoelectronic properties together with self-assembling features that are well suitable for low-temperature solution processing. Major blocks in realizing NIR organic lasing include low stimulated emission of narrow-bandgap molecules due to fast nonradiative decay and exciton-exciton annihilation, which is considered as a main loss channel of population inversion for organic lasers under high carrier densities. Here we designed and synthesized the small organic molecule (E)-3-(4-(di-p-tolylamino)phenyl)-1-(1-hydroxynaphthalen-2-yl)prop-2-en-1-one (DPHP) with amphiphilic nature, which elaborately self-assembles into micrometer-sized hemispheres that simultaneously serves as the NIR emission medium with a photoluminescence quantum efficiency of ∼15.2%, and the high-Q (∼1.4 × 10(3)) whispering gallery mode microcavity. Moreover, the radiative rate of DPHP hemispheres is enhanced up to ∼1.98 × 10(9) s(-1) on account of the exciton-vibrational coupling in the solid state with the J-type molecular-coupling component, and meanwhile the exciton-exciton annihilation process is eliminated. As a result, NIR lasing with a low threshold of ∼610 nJ/cm(2) is achieved in the single DPHP hemisphere at room temperature. Our demonstration is a major step toward incorporating the organic coherent light sources into the compact optoelectronic devices at NIR wavelengths.

  12. MOS spectroscopy with the JWST Near-Infrared Spectrometer

    NASA Astrophysics Data System (ADS)

    Karakla, Diane M.; Beck, Tracy; Gilbert, Karoline; Pontoppidan, Klaus Martin; Curtis, Gary; Shyrokov, Alexander

    2015-08-01

    The James Webb Space Telescope's Near-Infrared Spectrograph (NIRSpec) will feature astronomy’s first space-based, multi-object spectroscopic (MOS) capability enabled by the instrument’s micro-shutter array (MSA). The MSA is a four-quadrant fixed grid of nearly 250,000 tiny shutters that can be configured into slits on multiple astronomical targets in a field. In MOS mode, NIRSpec can obtain spectra of more than 100 targets simultaneously in one of three spectral bands (1.0 - 1.8 μm, 1.7 - 3.0 μm, and 2.9 - 5.0 μm) at medium (R~1000) or high resolution (R~2700) with the gratings, or at lower resolution (R~100, 0.6 - 5.0 μm) with the PRISM. The NIRSpec team and software developers at the Space Telescope Science Institute (STScI) have developed an MSA Planning Tool (MPT) to facilitate the complex observation planning process for a variety of observing strategies. The purpose of the tool is to find optimal pointings on the sky where many sources (or many high-valued sources) can be observed at a given pointing, or through a set of telescope dithers, and to design the associated MSA configurations at each position. The MPT is available to the astronomical community as part of the Astronomer’s Proposal Tool (APT), an integrated software package developed by STScI for the preparation of observing proposals. We will summarize the operational concept for MOS spectroscopy with the instrument, describe the MSA Planning Tool and its algorithms, and highlight recent developments that extend the tool’s applicability to diverse science cases.

  13. Near-infrared dyes for molecular probes and imaging

    NASA Astrophysics Data System (ADS)

    Patonay, Gabor; Beckford, Garfield; Strekowski, Lucjan; Henary, Maged; Kim, Jun Seok; Crow, Sidney

    2009-02-01

    Near-Infrared (NIR) fluorescence has been used both as an analytical tool as molecular probes and in in vitro or in vivo imaging of individual cells and organs. The NIR region (700-1100 nm) is ideal with regard to these applications due to the inherently lower background interference and the high molar absorptivities of NIR chromophores. NIR dyes are also useful in studying binding characteristics of large biomolecules, such as proteins. Throughout these studies, different NIR dyes have been evaluated to determine factors that control binding to biomolecules, including serum albumins. Hydrophobic character of NIR dyes were increased by introducing alkyl and aryl groups, and hydrophilic moieties e.g., polyethylene glycols (PEG) were used to increase aqueous solubility. Recently, our research group introduced bis-cyanines as innovative NIR probes. Depending on their microenvironment, bis-cyanines can exist as an intramolecular dimer with the two cyanines either in a stacked form, or in a linear conformation in which the two subunits do not interact with each other. In this intramolecular H-aggregate, the chromophore has a low extinction coefficient and low fluorescence quantum yield. Upon addition of biomolecules, the H-and D- bands are decreased and the monomeric band is increased, with concomitant increase in fluorescence intensity. Introduction of specific moieties into the NIR dye molecules allows for the development of physiological molecular probes to detect pH, metal ions and other parameters. Examples of these applications include imaging and biomolecule characterizations. Water soluble dyes are expected to be excellent candidates for both in vitro and in vivo imaging of cells and organs.

  14. Near-infrared Variability in the Orion Nebula Cluster

    NASA Astrophysics Data System (ADS)

    Rice, Thomas S.; Reipurth, Bo; Wolk, Scott J.; Vaz, Luiz Paulo; Cross, N. J. G.

    2015-10-01

    Using UKIRT on Mauna Kea, we have carried out a new near-infrared J, H, K monitoring survey of almost a square degree of the star-forming Orion Nebula Cluster with observations on 120 nights over three observing seasons, spanning a total of 894 days. We monitored ˜15,000 stars down to J≈ 20 using the WFCAM instrument, and have extracted 1203 significantly variable stars from our data. By studying variability in young stellar objects (YSOs) in the H - K, K color-magnitude diagram, we are able to distinguish between physical mechanisms of variability. Many variables show color behavior indicating either dust-extinction or disk/accretion activity, but we find that when monitored for longer periods of time, a number of stars shift between these two variability mechanisms. Further, we show that the intrinsic timescale of disk/accretion variability in young stars is longer than that of dust-extinction variability. We confirm that variability amplitude is statistically correlated with evolutionary class in all bands and colors. Our investigations of these 1203 variables have revealed 73 periodic AA Tau type variables, many large-amplitude and long-period (P\\gt 15 days) YSOs, including three stars showing widely spaced periodic brightening events consistent with circumbinary disk activity, and four new eclipsing binaries. These phenomena and others indicate the activity of long-term disk/accretion variability processes taking place in young stars. We have made the light curves and associated data for these 1203 variables available online.

  15. Imaging spectrometer for ultraviolet-near-infrared microspectroscopy

    NASA Astrophysics Data System (ADS)

    Johansson, Thomas; Pettersson, Anders

    1997-05-01

    We describe the design and performance of a new high-speed imaging spectrometer system developed for the spectral analysis of micrometer-sized features in transmitted light. The instrument utilizes the wavelength range from ultraviolet (UV) to near infrared (NIR) (250-975 nm). The extension into the ultraviolet range is to our knowledge unique. The system comprises two white light sources (xenon and halogen lamps), a motorized sample stage, microscope optics with slit-determined field of view, and three (UV, visible and NIR) parallel optical recording channels. The dispersive optical recording system is based on holographic gratings and uses charge-coupled-device (CCD) cameras as imaging detectors. The instrument has been fully integrated with data acquisition and control systems. Subsequent data analysis is performed by dedicated software. The instrument provides spectral images from narrow wavelength bands (5 nm). In such an image the spectral information from a selected wavelength band is depicted with its corresponding geometric location, i.e., a single pixel on the CCD chip. Hence, objects can be visualized in different wavelength bands and a spectrum can easily be produced for each location of the object. The instrument can measure objects up to 900 μm×27 mm with a spectral resolution better than 5 nm and a spatial resolution better than 5 μm. The imaging spectrometer system provides a powerful combination of spectroscopy and image processing for use in many applications in research, control and quality assessment, where spectral information and its location are of interest. Although the system has been primarily developed for applications in the pulp and paper industry, it has a vast potential for spectroscopic analysis with a micrometer spatial resolution in general and for measurements of impurities and their locations in products in particular. As an example of a measurement, spectral image data from a wood fiber are presented.

  16. Nondestructive Assessment of Engineered Cartilage Composition by Near Infrared Spectroscopy.

    PubMed

    McGoverin, Cushla M; Hanifi, Arash; Palukuru, Uday P; Yousefi, Farzad; Glenn, Padraig B M; Shockley, Michael; Spencer, Richard G; Pleshko, Nancy

    2016-03-01

    Tissue engineering presents a strategy to overcome the limitations of current tissue healing methods. Scaffolds, cells, external growth factors and mechanical input are combined in an effort to obtain constructs with properties that mimic native tissues. However, engineered constructs developed using similar culture environments can have very different matrix composition and biomechanical properties. Accordingly, a nondestructive technique to assess constructs during development such that appropriate compositional endpoints can be defined is desirable. Near infrared spectroscopy (NIRS) analysis is a modality being investigated to address the challenges associated with current evaluation techniques, which includes nondestructive compositional assessment. In the present study, cartilage tissue constructs were grown using chondrocytes seeded onto polyglycolic acid (PGA) scaffolds in similar environments in three separate tissue culture experiments and monitored using NIRS. Multivariate partial least squares (PLS) analysis models of NIR spectra were calculated and used to predict tissue composition, with biochemical assay information used as the reference data. Results showed that for combined data from all tissue culture experiments, PLS models were able to assess composition with significant correlations to reference values, including engineered cartilage water (at 5200 cm(-1), R = 0.68, p = 0.03), proteoglycan (at 4310 cm(-1), R = 0.82, p = 0.007), and collagen (at 4610 cm(-1), R = 0.84, p = 0.005). In addition, degradation of PGA was monitored using specific NIRS frequencies. These results demonstrate that NIR spectroscopy combined with multivariate analysis provides a nondestructive modality to assess engineered cartilage, which could provide information to determine the optimal time for tissue harvest for clinical applications.

  17. Direct production of graphene nanosheets for near infrared photoacoustic imaging.

    PubMed

    Patel, Mehulkumar A; Yang, Hao; Chiu, Pui Lam; Mastrogiovanni, Daniel D T; Flach, Carol R; Savaram, Keerthi; Gomez, Lesly; Hemnarine, Ashley; Mendelsohn, Richard; Garfunkel, Eric; Jiang, Huabei; He, Huixin

    2013-09-24

    Hummers method is commonly used for the fabrication of graphene oxide (GO) from graphite particles. The oxidation process also leads to the cutting of graphene sheets into small pieces. From a thermodynamic perspective, it seems improbable that the aggressive, somewhat random oxidative cutting process could directly result in graphene nanosheets without destroying the intrinsic π-conjugated structures and the associated exotic properties of graphene. In Hummers method, both KMnO4 and NO2(+) (nitronium ions) in concentrated H2SO4 solutions act as oxidants via different oxidation mechanisms. From both experimental observations and theoretical calculations, it appears that KMnO4 plays a major role in the observed oxidative cutting and unzipping processes. We find that KMnO4 also limits nitronium oxidative etching of graphene basal planes, therefore slowing down graphene fracturing processes for nanosheet fabrication. By intentionally excluding KMnO4 and exploiting pure nitronium ion oxidation, aided by the unique thermal and kinetic effects induced by microwave heating, we find that graphite particles can be converted into graphene nanosheets with their π-conjugated aromatic structures and properties largely retained. Without the need of any postreduction processes to remove the high concentration of oxygenated groups that results from Hummers GO formation, the graphene nanosheets as-fabricated exhibit strong absorption, which is nearly wavelength-independent in the visible and near-infrared (NIR) regions, an optical property typical for intrinsic graphene sheets. For the first time, we demonstrate that strong photoacoustic signals can be generated from these graphene nanosheets with NIR excitation. The photo-to-acoustic conversion is weakly dependent on the wavelength of the NIR excitation, which is different from all other NIR photoacoustic contrast agents previously reported.

  18. Spitzer and near-infrared observations of the young supernova remnant 3C397

    NASA Astrophysics Data System (ADS)

    Rho, Jeonghee; Jarrett, Tom

    2016-06-01

    We present Spitzer IRS, IRAC and MIPS observations and near-infrared imaging and spectroscopy of the young supernova remnant 3C397 (G41.1-0.2). Near-infrared observations were made using the Palomar 200 inch telescope. Both mid- and near-infrared spectra are dominated by Fe lines and near-infrared imaging shows bright Fe emission with a shell-like morphology. There is no molecular hydrogen line belong to the SNR and some are in background. The Ni, Ar, S and Si lines are detected using IRS and hydrogen recombination lines are detected in near-infrared. Two nickel lines at 18.24 and 10.69 micron are detected. 3C397 is ejecta-dominated, and our observations support 3C397 to be a Type Ia supernova.

  19. MULTI-COLOR OPTICAL AND NEAR-INFRARED LIGHT CURVES OF 64 STRIPPED-ENVELOPE CORE-COLLAPSE SUPERNOVAE

    SciTech Connect

    Bianco, F. B.; Modjaz, M.; Hicken, M.; Friedman, A.; Kirshner, R. P.; Challis, P.; Marion, G. H.; Bloom, J. S.; Wood-Vasey, W. M.; Rest, A.

    2014-08-01

    We present a densely sampled, homogeneous set of light curves of 64 low-redshift (z ≲ 0.05) stripped-envelope supernovae (SNe of Type IIb, Ib, Ic, and Ic-BL). These data were obtained between 2001 and 2009 at the Fred L. Whipple Observatory (FLWO) on Mount Hopkins in Arizona, with the optical FLWO 1.2 m and the near-infrared (NIR) Peters Automated Infrared 1.3 m telescopes. Our data set consists of 4543 optical photometric measurements on 61 SNe, including a combination of U BV RI, U BV r{sup ′}i{sup ′}, and u{sup ′} BV r{sup ′}i{sup ′}, and 1919 JHK{sub s} NIR measurements on 25 SNe. This sample constitutes the most extensive multi-color data set of stripped-envelope SNe to date. Our photometry is based on template-subtracted images to eliminate any potential host-galaxy light contamination. This work presents these photometric data, compares them with data in the literature, and estimates basic statistical quantities: date of maximum, color, and photometric properties. We identify promising color trends that may permit the identification of stripped-envelope SN subtypes from their photometry alone. Many of these SNe were observed spectroscopically by the Harvard-Smithsonian Center for Astrophysics (CfA) SN group, and the spectra are presented in a companion paper. A thorough exploration that combines the CfA photometry and spectroscopy of stripped-envelope core-collapse SNe will be presented in a follow-up paper.

  20. Light shift from ultraviolet to near infrared light: Cerenkov luminescence with gold nanocluster - near infrared (AuNc-NIR) conjugates

    NASA Astrophysics Data System (ADS)

    Yoo, Su Woong; Mun, Hyoyoung; Oh, Gyungseok; Ryu, Youngjae; Kim, Min-Gon; Chung, Euiheon

    2015-03-01

    Cerenkov luminescence (CL) is generated when a charged particle moves faster than the speed of light in dielectric media. Recently CL imaging becomes an emerging technique with the use of radioisotopes. However, due to relatively weak blue light production and massive tissue attenuation, CL has not been applied widely. Therefore, we attempted to shift the CL emission to more near infrared (NIR) spectrum for better tissue penetration by using Cerenkov Radiation Energy Transfer (CRET). Gold nanoclusters were conjugated with NIR dye molecules (AuNc-IR820 and AuNc-ICG) to be activated with ultraviolet light. We found optimal conjugate concentrations of AuNc-NIR conjugates by spectroscopy system to generate maximal photon emission. When exposed by ultraviolet light, the emission of NIR light from the conjugates were verified. In quantitative analysis, AuNc-NIR conjugates emit brighter light signal than pure AuNc. This result implies that NIR fluorescent dyes (both IR820 and ICG) can be excited by the emission from AuNc. Following the above baseline experiment, we mixed F-18 fluorodeoxyglucose (F-18 FDG) radioisotope to the AuNc- NIR conjugates, to confirm NIR emission induced from Cerenkov radiation. Long pass filter was used to block Cerenkov luminescence and to collect the emission from AuNc-NIR conjugates. Instead of one long exposure imaging with CCD, we used multiple frame scheme to eliminate gamma radiation strike in each frame prior to combination. In summary, we obtained NIR emission light from AuNc-NIR conjugated dyes that is induced from CL. We plan to perform in vivo small animal imaging with these conjugates to assess better tissue penetration.

  1. Spectra Transfer Between a Fourier Transform Near-Infrared Laboratory and a Miniaturized Handheld Near-Infrared Spectrometer.

    PubMed

    Hoffmann, Uwe; Pfeifer, Frank; Hsuing, Chang; Siesler, Heinz W

    2016-05-01

    The aim of this contribution is to demonstrate the transfer of spectra that have been measured on two different laboratory Fourier transform near-infrared (FT-NIR) spectrometers to the format of a handheld instrument by measuring only a few samples with both spectrometer types. Thus, despite the extreme differences in spectral range and resolution, spectral data sets that have been collected and quantitative as well as qualitative calibrations that have been developed thereof, respectively, over a long period on a laboratory instrument can be conveniently transferred to the handheld system. Thus, the necessity to prepare completely new calibration samples and the effort required to develop calibration models when changing hardware platforms is minimized. The enabling procedure is based on piecewise direct standardization (PDS) and will be described for the data sets of a quantitative and a qualitative application case study. For this purpose the spectra measured on the FT-NIR laboratory spectrometers were used as "master" data and transferred to the "target" format of the handheld instrument. The quantitative test study refers to transmission spectra of three-component liquid solvent mixtures whereas the qualitative application example encompasses diffuse reflection spectra of six different current polymers. To prove the performance of the transfer procedure for quantitative applications, partial least squares (PLS-1) calibrations were developed for the individual components of the solvent mixtures with spectra transferred from the master to the target instrument and the cross-validation parameters were compared with the corresponding parameters obtained for spectra measured on the master and target instruments, respectively. To test the retention of the discrimination ability of the transferred polymer spectra sets principal component analyses (PCAs) were applied exemplarily for three of the six investigated polymers and their identification was demonstrated by

  2. THE COSMIC NEAR-INFRARED BACKGROUND. II. FLUCTUATIONS

    SciTech Connect

    Fernandez, Elizabeth R.; Komatsu, Eiichiro; Shapiro, Paul R.; Iliev, Ilian T.

    2010-02-20

    The near-infrared background (NIRB) is one of a few methods that can be used to observe the redshifted light from early stars at a redshift of 6 and above, and thus it is imperative to understand the significance of any detection or nondetection of the NIRB. Fluctuations of the NIRB can provide information on the first structures, such as halos and their surrounding ionized regions in the intergalactic medium (IGM). We combine, for the first time, N-body simulations, radiative transfer code, and analytic calculations of luminosity of early structures to predict the angular power spectrum (C{sub l} ) of fluctuations in the NIRB. We study in detail the effects of various assumptions about the stellar mass, the initial mass spectrum of stars, the metallicity, the star formation efficiency (f{sub *}), the escape fraction of ionizing photons (f{sub esc}), and the star formation timescale (t{sub SF}), on the amplitude as well as the shape of C{sub l} . The power spectrum of NIRB fluctuations is maximized when f{sub *} is the largest (as C{sub l} {proportional_to} f {sup 2}{sub *}) and f{sub esc} is the smallest (as more nebular emission is produced within halos). A significant uncertainty in the predicted amplitude of C{sub l} exists due to our lack of knowledge of t{sub SF} of these early populations of galaxies, which is equivalent to our lack of knowledge of the mass-to-light ratio of these sources. We do not see a turnover in the NIRB angular power spectrum of the halo contribution, which was claimed to exist in the literature, and explain this as the effect of high levels of nonlinear bias that was ignored in the previous calculations. This is partly due to our choice of the minimum mass of halos contributing to NIRB ({approx}2 x 10{sup 9} M{sub sun}), and a smaller minimum mass, which has a smaller nonlinear bias, may still exhibit a turnover. Therefore, our results suggest that both the amplitude and shape of the NIRB power spectrum provide important information

  3. Near-infrared extinction with discretised stellar colours

    NASA Astrophysics Data System (ADS)

    Juvela, M.; Montillaud, J.

    2016-01-01

    Context. Near-infrared (NIR) extinction remains one of the most reliable methods of measuring the column density of dense interstellar clouds. Extinction can be estimated using the reddening of the light of background stars. Several methods exist (e.g., NICE, NICER, NICEST, GNICER) to combine observations of several NIR bands into extinction maps. Aims: We present a new method of estimating extinction based on NIR multiband observations and examine its performance. Methods: Our basic method uses a discretised version of the distribution of intrinsic stellar colours directly. The extinction of individual stars and the average over a resolution element are estimated with Markov chain Monte Carlo (MCMC) methods. Several variations of the basic method are tested, and the results are compared to NICER calculations. Results: In idealised settings or when photometric errors are large, the results of the new method are very close to those of NICER. Clear advantages can be seen when the distribution of intrinsic colours cannot be described well with a single covariance matrix. The MCMC framework makes it easy to consider additional effects such as those of completeness limits and contamination by galaxies or foreground stars. A priori information about relative column density variations at sub-beam scales can result in a significant increase in accuracy. For observations of high photometric precision, the results could be further improved by considering the magnitude dependence of the intrinsic colours. Conclusions: The MCMC computations are time-consuming, but the calculation of large extinction maps is already practical. The same methods can be used with direct optimisation, with significantly less computational work. Faster methods, like NICER, perform very well in many cases even when the basic assumptions no longer hold. The new methods are useful mostly when photometric errors are small, the distribution of intrinsic colours is well known, or one has prior knowledge

  4. Principal components analysis of Mars in the near-infrared

    NASA Astrophysics Data System (ADS)

    Klassen, David R.

    2009-11-01

    Principal components analysis and target transformation are applied to near-infrared image cubes of Mars in a study to disentangle the spectra into a small number of spectral endmembers and characterize the spectral information. The image cubes are ground-based telescopic data from the NASA Infrared Telescope Facility during the 1995 and 1999 near-aphelion oppositions when ice clouds were plentiful [ Clancy, R.T., Grossman, A.W., Wolff, M.J., James, P.B., Rudy, D.J., Billawala, Y.N., Sandor, B.J., Lee, S.W., Muhleman, D.O., 1996. Icarus 122, 36-62; Wolff, M.J., Clancy, R.T., Whitney, B.A., Christensen, P.R., Pearl, J.C., 1999b. In: The Fifth International Conference on Mars, July 19-24, 1999, Pasadena, CA, pp. 6173], and the 2003 near-perihelion opposition when ice clouds are generally limited to topographically high regions (volcano cap clouds) but airborne dust is more common [ Martin, L.J., Zurek, R.W., 1993. J. Geophys. Res. 98 (E2), 3221-3246]. The heart of the technique is to transform the data into a vector space along the dimensions of greatest spectral variance and then choose endmembers based on these new "trait" dimensions. This is done through a target transformation technique, comparing linear combinations of the principal components to a mineral spectral library. In general Mars can be modeled, on the whole, with only three spectral endmembers which account for almost 99% of the data variance. This is similar to results in the thermal infrared with Mars Global Surveyor Thermal Emission Spectrometer data [Bandfield, J.L., Hamilton, V.E., Christensen, P.R., 2000. Science 287, 1626-1630]. The globally recovered surface endmembers can be used as inputs to radiative transfer modeling in order to measure ice abundance in martian clouds [Klassen, D.R., Bell III, J.F., 2002. Bull. Am. Astron. Soc. 34, 865] and a preliminary test of this technique is also presented.

  5. Effects of Near-Infrared Laser on Neural Cell Activity

    NASA Astrophysics Data System (ADS)

    Mochizuki-Oda, Noriko; Kataoka, Yosky; Yamada, Hisao; Awazu, Kunio

    2004-08-01

    Near-infrared laser has been used to relieve patients from various kinds of pain caused by postherpetic neuralgesia, myofascial dysfunction, surgical and traumatic wound, cancer, and rheumatoid arthritis. Clinically, He-Ne (λ=632.8 nm, 780 nm) and Ga-Al-As (805 ± 25 nm) lasers are used to irradiate trigger points or nerve ganglion. However the precise mechanisms of such biological actions of the laser have not yet been resolved. Since laser therapy is often effective to suppress the pain caused by hyperactive excitation of sensory neurons, interactions with laser light and neural cells are suggested. As neural excitation requires large amount of energy liberated from adenosine triphosphate (ATP), we examined the effect of 830-nm laser irradiation on the energy metabolism of the rat central nervous system and isolated mitochondria from brain. The diode laser was applied for 15 min with irradiance of 4.8 W/cm2 on a 2 mm-diameter spot at the brain surface. Tissue ATP content of the irradiated area in the cerebral cortex was 19 % higher than that of the non-treated area (opposite side of the cortex), whereas the ADP content showed no significant difference. Irradiation at another wavelength (652 nm) had no effect on either ATP or ADP contents. The temperature of the brain tissue was increased 4.5 - 5.0 °C during the irradiation of both 830-nm and 652-nm laser light. Direct irradiation of the mitochondrial suspension did not show any wavelength-dependent acceleration of respiration rate nor ATP synthesis. These results suggest that the increase in tissue ATP content did not result from the thermal effect, but from specific effect of the laser operated at 830 nm. Electrophysiological studies showed the hyperpolarization of membrane potential of isolated neurons and decrease in membrane resistance with irradiation of the laser, suggesting an activation of potassium channels. Intracellular ATP is reported to regulate some kinds of potassium channels. Possible mechanisms

  6. Near-Infrared Spectra of Type Ia Supernovae

    NASA Technical Reports Server (NTRS)

    Marion, G. H.; Hoeflich, P.; Vacca, W. D.; Wheeler, J. C.

    2003-01-01

    We report near-infrared (NIR) spectroscopic observations of 12 'branch-normal' Type Ia supernovae (SNe Ia) that cover the wavelength region from 0.8 to 2.5 microns. Our sample more than doubles the number of SNe Ia with published NIR spectra within 3 weeks of maximum light. The epochs of observation range from 13 days before maximum light to 18 days after maximum light. A detailed model for a Type Ia supernovae is used to identify spectral features. The Doppler shifts of lines are measured to obtain the velocity and thus the radial distribution of elements. The NIR is an extremely useful tool to probe the chemical structure in the layers of SNe Ia ejecta. This wavelength region is optimal for examining certain products of the SNe Ia explosion that may be blended or obscured in other spectral regions. We identify spectral features from Mg II, Ca II, Si II, Fe II, Co II, Ni II, and possibly Mn II. We find no indications for hydrogen, helium, or carbon in the spectra. The spectral features reveal important clues about the physical characteristics of SNe Ia. We use the features to derive upper limits for the amount of unburned matter, to identify the transition regions from explosive carbon to oxygen burning and from partial to complete silicon burning, and to estimate the level of mixing during and after the explosion. Elements synthesized in the outer layers during the explosion appear to remain in distinct layers. That provides strong evidence for the presence of a detonation phase during the explosion as it occurs in delayed detonation or merger models. Mg II velocities are found to exceed 11,000 - 15,000 km/s, depending on the individual SNe Ia. That result suggests that burning during the explosion reaches the outermost layers of the progenitor and limits the amount of unburned material to less than 10% of the mass of the progenitor. Small residuals of unburned material are predicted by delayed detonation models but are inconsistent with pure deflagration or

  7. Fresh Soil Sensing using Visible and Near Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Maleki, M. R.

    2009-04-01

    Fast, precise and affordable soil analytical techniques are needed for the determination of soil fertility of each zone of a field in site specific land management. The objective of this poster is to demonstrate how nutrients can be estimated from fresh soil using visible (VIS) and near infrared (NIR) spectroscopy method. This could be carried out by summarizing the methodology to develop a calibration model for soil phosphorus with the VIS-NIR spectroscopy method. Obviously, it can be simply extended for other nutrients with the same methodology. A large samples set should be collected from different fields with a wide range of soil type and texture. The samples in this set should be represented a wide range of moisture content and soil nutrient which is desired to be calibrated by the spectroscopy technique. Immediately after sampling, the samples should be kept in a cold room (± 1 °C) until the time of the spectral measurement and the chemical analysis. The samples should be taken from the cold room one hour before the spectral measurement to ensure that the samples were at room temperature and no condensation occurs on the optical instruments. Each soil sample was thoroughly mixed and debris such as plant material and stones were removed. The soil sample was divided into three parts, one part for spectral measurement, another part for chemical analysis and the rest was archived. The part for chemical analysis should be examined for their soil nutrients. A small amount of soil (about 30 g) should be placed in a small plastic petridish (e.g. 7.5 mm depth and 30 mm diameter). The soil in the petridish should be first pressed and then carefully levelled in order to obtain a smooth surface for a maximum light reflectance. Soil samples should be put under the spectrophotometer. Three reflectance spectra should be measured on each soil specimen by rotating the plastic cups over 120°. Having finished measuring, the reflectance data should be put against the chemical

  8. RESOLVED NEAR-INFRARED STELLAR POPULATIONS IN NEARBY GALAXIES

    SciTech Connect

    Dalcanton, Julianne J.; Williams, Benjamin F.; Rosenfield, Philip A.; Gilbert, Karoline E-mail: ben@astro.washington.edu E-mail: kgilbert@astro.washington.edu; and others

    2012-01-01

    We present near-infrared (NIR) color-magnitude diagrams (CMDs) for the resolved stellar populations within 26 fields of 23 nearby galaxies ({approx}< 4 Mpc), based on images in the F110W and F160W filters taken with the Wide-Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). The CMDs are measured in regions spanning a wide range of star formation histories, including both old dormant and young star-forming populations. We match key NIR CMD features with their counterparts in more familiar optical CMDs, and identify the red core helium-burning (RHeB) sequence as a significant contributor to the NIR flux in stellar populations younger than a few 100 Myr old. The strength of this feature suggests that the NIR mass-to-light ratio can vary significantly on short timescales in star-forming systems. The NIR luminosity of star-forming galaxies is therefore not necessarily proportional to the stellar mass. We note that these individual RHeB stars may also be misidentified as old stellar clusters in images of nearby galaxies. For older stellar populations, we discuss the CMD location of asymptotic giant branch (AGB) stars in the HST filter set and explore the separation of AGB subpopulations using a combination of optical and NIR colors. We empirically calibrate the magnitude of the NIR tip of the red giant branch in F160W as a function of color, allowing future observations in this widely adopted filter set to be used for distance measurements. We also analyze the properties of the NIR red giant branch (RGB) as a function of metallicity, showing a clear trend between NIR RGB color and metallicity. However, based on the current study, it appears unlikely that the slope of the NIR RGB can be used as an effective metallicity indicator in extragalactic systems with comparable data. Finally, we highlight issues with scattered light in the WFC3, which becomes significant for exposures taken close to a bright Earth limb.

  9. Determination of plant silicon content with near infrared reflectance spectroscopy

    PubMed Central

    Smis, Adriaan; Ancin Murguzur, Francisco Javier; Struyf, Eric; Soininen, Eeva M.; Herranz Jusdado, Juan G.; Meire, Patrick; Bråthen, Kari Anne

    2014-01-01

    Silicon (Si) is one of the most common elements in the earth bedrock, and its continental cycle is strongly biologically controlled. Yet, research on the biogeochemical cycle of Si in ecosystems is hampered by the time and cost associated with the currently used chemical analysis methods. Here, we assessed the suitability of Near Infrared Reflectance Spectroscopy (NIRS) for measuring Si content in plant tissues. NIR spectra depend on the characteristics of the present bonds between H and N, C and O, which can be calibrated against concentrations of various compounds. Because Si in plants always occurs as hydrated condensates of orthosilicic acid (Si(OH)4), linked to organic biomolecules, we hypothesized that NIRS is suitable for measuring Si content in plants across a range of plant species. We based our testing on 442 samples of 29 plant species belonging to a range of growth forms. We calibrated the NIRS method against a well-established plant Si analysis method by using partial least-squares regression. Si concentrations ranged from detection limit (0.24 ppmSi) to 7.8% Si on dry weight and were well predicted by NIRS. The model fit with validation data was good across all plant species (n = 141, R2 = 0.90, RMSEP = 0.24), but improved when only graminoids were modeled (n = 66, R2 = 0.95, RMSEP = 0.10). A species specific model for the grass Deschampsia cespitosa showed even slightly better results than the model for all graminoids (n = 16, R2 = 0.93, RMSEP = 0.015). We show for the first time that NIRS is applicable for determining plant Si concentration across a range of plant species and growth forms, and represents a time- and cost-effective alternative to the chemical Si analysis methods. As NIRS can be applied concurrently to a range of plant organic constituents, it opens up unprecedented research possibilities for studying interrelations between Si and other plant compounds in vegetation, and for addressing the role of Si in ecosystems across a range of Si

  10. [Application of near infrared reflectance spectroscopy to predict meat chemical compositions: a review].

    PubMed

    Tao, Lin-Li; Yang, Xiu-Juan; Deng, Jun-Ming; Zhang, Xi

    2013-11-01

    In contrast to conventional methods for the determination of meat chemical composition, near infrared reflectance spectroscopy enables rapid, simple, secure and simultaneous assessment of numerous meat properties. The present review focuses on the use of near infrared reflectance spectroscopy to predict meat chemical compositions. The potential of near infrared reflectance spectroscopy to predict crude protein, intramuscular fat, fatty acid, moisture, ash, myoglobin and collagen of beef, pork, chicken and lamb is reviewed. This paper discusses existing questions and reasons in the current research. According to the published results, although published results vary considerably, they suggest that near-infrared reflectance spectroscopy shows a great potential to replace the expensive and time-consuming chemical analysis of meat composition. In particular, under commercial conditions where simultaneous measurements of different chemical components are required, near infrared reflectance spectroscopy is expected to be the method of choice. The majority of studies selected feature-related wavelengths using principal components regression, developed the calibration model using partial least squares and modified partial least squares, and estimated the prediction accuracy by means of cross-validation using the same sample set previously used for the calibration. Meat fatty acid composition predicted by near-infrared spectroscopy and non-destructive prediction and visualization of chemical composition in meat using near-infrared hyperspectral imaging and multivariate regression are the hot studying field now. On the other hand, near infrared reflectance spectroscopy shows great difference for predicting different attributes of meat quality which are closely related to the selection of calibration sample set, preprocessing of near-infrared spectroscopy and modeling approach. Sample preparation also has an important effect on the reliability of NIR prediction; in particular

  11. Optical Clearing of the Skin for Near-Infrared Fluorescence Image-Guided Surgery

    PubMed Central

    Matsui, Aya; Lomnes, Stephen J.; Frangioni, John V.

    2009-01-01

    Near-infrared (NIR) light penetrates relatively deep into skin, but its usefulness for biomedical imaging is constrained by high scattering of living tissue. Previous studies have suggested that treatment with hyperosmotic “clearing” agents might change the optical properties of tissue, resulting in improved photon transport and reduced scatter. Since this would have a profound impact on image-guided surgery, we sought to quantify the magnitude of the optical clearing effect in living subjects. A custom NIR imaging system was used to perform sentinel lymph node mapping and superficial perforator angiography in vivo on 35 kg pigs in the presence or absence of glycerol or PPG:PEG pre-treatment of skin. Ex vivo, NIR fluorescent standards were placed at a fixed distance beneath sections of excised porcine skin, either preserved in saline or stored dry, then treated or not treated with glycerol. Fluorescence intensity through the skin was quantified and analyzed statistically. Surprisingly, the expected increase in intensity was not measurable either in vivo or ex vivo, unless the skin was previously dried. Histological evaluation showed a morphological difference only in stratum corneum, with this difference being negligible in living tissue. In conclusion, topically applied hyperosmotic agents are ineffective for image-guided surgery of living subjects. PMID:19405749

  12. Near-infrared spectroscopy and polysomnography during all-night sleep in human subjects

    NASA Astrophysics Data System (ADS)

    Fantini, Sergio; Aggarwal, Payal; Chen, Kathleen; Franceschini, Maria Angela; Ehrenberg, Bruce L.

    2003-10-01

    We have performed cerebral near-infrared spectroscopy (NIRS) and polysomnography (electro-encephalography, electro-oculography, electro-myography, pulse oximetry, and respiratory monitoring) during all-night sleep in five human subjects. Polysomnography data were used for sleep staging, while NIRS data were used to measure the concentration and the oxygen saturation of hemoglobin in the frontal brain region. Immediately after sleep onset we observed a decrease in the cerebral concentration of oxy-hemoglobin ([HbO2]) and an increase in the concentration of deoxy-hemoglobin ([Hb]), consistent with a decrease in the cerebral blood flow velocity or an increase in cerebral metabolic rate of oxygen. An opposite trend (increase in [HbO2] and decrease in [Hb]) was usually observed after transition to deep sleep (stages III and IV). During rapid eye movement (REM) sleep, we observed an increase in [HbO2] and decrease in [Hb], consistent with an increase in the cerebral blood flow that overcompensates the increase in the metabolic rate of oxygen associated with REM sleep.

  13. Near-Infrared Squaraine Dye Encapsulated Micelles for in Vivo Fluorescence and Photoacoustic Bimodal Imaging.

    PubMed

    Sreejith, Sivaramapanicker; Joseph, James; Lin, Manjing; Menon, Nishanth Venugopal; Borah, Parijat; Ng, Hao Jun; Loong, Yun Xian; Kang, Yuejun; Yu, Sidney Wing-Kwong; Zhao, Yanli

    2015-06-23

    Combined near-infrared (NIR) fluorescence and photoacoustic imaging techniques present promising capabilities for noninvasive visualization of biological structures. Development of bimodal noninvasive optical imaging approaches by combining NIR fluorescence and photoacoustic tomography demands suitable NIR-active exogenous contrast agents. If the aggregation and photobleaching are prevented, squaraine dyes are ideal candidates for fluorescence and photoacoustic imaging. Herein, we report rational selection, preparation, and micelle encapsulation of an NIR-absorbing squaraine dye (D1) for in vivo fluorescence and photoacoustic bimodal imaging. D1 was encapsulated inside micelles constructed from a biocompatible nonionic surfactant (Pluoronic F-127) to obtain D1-encapsulated micelles (D1(micelle)) in aqueous conditions. The micelle encapsulation retains both the photophysical features and chemical stability of D1. D1(micelle) exhibits high photostability and low cytotoxicity in biological conditions. Unique properties of D1(micelle) in the NIR window of 800-900 nm enable the development of a squaraine-based exogenous contrast agent for fluorescence and photoacoustic bimodal imaging above 820 nm. In vivo imaging using D1(micelle), as demonstrated by fluorescence and photoacoustic tomography experiments in live mice, shows contrast-enhanced deep tissue imaging capability. The usage of D1(micelle) proven by preclinical experiments in rodents reveals its excellent applicability for NIR fluorescence and photoacoustic bimodal imaging.

  14. Fourth near-infrared optical window for assessment of bone and other tissues

    NASA Astrophysics Data System (ADS)

    Sordillo, Diana C.; Sordillo, Laura A.; Sordillo, Peter P.; Alfano, Robert R.

    2016-02-01

    Recently, additional near-infrared (NIR) optical windows beyond the conventional first therapeutic window have been utilized for deep tissue imaging through scattering media. Biomedical applications using a second optical window (1100 to 1300 nm) and a third (1600 to 1870 nm) are emerging. A fourth window (2100 to 2300 nm) has been largely ignored due to high water absorption and a lack of high sensitivity imaging detectors and ultrafast laser sources. In this study, optical properties of bone in this fourth NIR optical window, were investigated. Results were compared to those seen at the first, second and third windows, and are consistent with our previous work on malignant and benign breast and prostate tissues. Bone and malignant tissues showed highest uptake in the third and fourth windows. As collagen is a major chromophore with prominent spectral peaks between 2100 and 2300 nm, it may be that the fourth optical window is particularly useful for studying tissues with a higher collagen content, such as bone or malignant tumors.

  15. An optogenetic system based on bacterial phytochrome controllable with near-infrared light

    PubMed Central

    Kaberniuk, Andrii A.; Shemetov, Anton A.; Verkhusha, Vladislav V.

    2016-01-01

    Light-mediated control of protein-protein interactions to regulate metabolic pathways is an important approach of optogenetics. Here, we report the first optogenetic system based on a reversible light-induced binding between a bacterial phytochrome BphP1 and its natural partner PpsR2 from Rhodopseudomonas palustris bacteria. We extensively characterized the BphP1–PpsR2 interaction both in vitro and in mammalian cells, and then used it to translocate target proteins to specific cellular compartments, such as plasma membrane and nucleus. Applying this approach we achieved a light-control of cell morphology resulting in the substantial increase of cell area. We next demonstrated the light-induced gene expression with the 40-fold contrast in cultured cells, 32-fold subcutaneously and 5.7-fold in deep tissues in mice. The unique characteristics of the BphP1–PpsR2 optogenetic system are its sensitivity to 740–780 nm near-infrared light, ability to utilize an endogenous biliverdin chromophore in eukaryotes including mammals, and spectral compatibility with blue-light optogenetic systems. PMID:27159085

  16. Recent advances in near-infrared fluorescence-guided imaging surgery using indocyanine green.

    PubMed

    Namikawa, Tsutomu; Sato, Takayuki; Hanazaki, Kazuhiro

    2015-12-01

    Near-infrared (NIR) fluorescence imaging has better tissue penetration, allowing for the effective rejection of excitation light and detection deep inside organs. Indocyanine green (ICG) generates NIR fluorescence after illumination by an NIR ray, enabling real-time intraoperative visualization of superficial lymphatic channels and vessels transcutaneously. The HyperEye Medical System (HEMS) can simultaneously detect NIR rays under room light to provide color imaging, which enables visualization under bright light. Thus, NIR fluorescence imaging using ICG can provide for excellent diagnostic accuracy in detecting sentinel lymph nodes in cancer and microvascular circulation in various ischemic diseases, to assist us with intraoperative decision making. Including HEMS in this system could further improve the sentinel lymph node mapping and intraoperative identification of blood supply in reconstructive organs and ischemic diseases, making it more attractive than conventional imaging. Moreover, the development of new laparoscopic imaging systems equipped with NIR will allow fluorescence-guided surgery in a minimally invasive setting. Future directions, including the conjugation of NIR fluorophores to target specific cancer markers might be realistic technology with diagnostic and therapeutic benefits.

  17. Bright monomeric near-infrared fluorescent proteins as tags and biosensors for multiscale imaging

    PubMed Central

    Shcherbakova, Daria M.; Baloban, Mikhail; Emelyanov, Alexander V.; Brenowitz, Michael; Guo, Peng; Verkhusha, Vladislav V.

    2016-01-01

    Monomeric near-infrared (NIR) fluorescent proteins (FPs) are in high demand as protein tags and components of biosensors for deep-tissue imaging and multicolour microscopy. We report three bright and spectrally distinct monomeric NIR FPs, termed miRFPs, engineered from bacterial phytochrome, which can be used as easily as GFP-like FPs. miRFPs are 2–5-fold brighter in mammalian cells than other monomeric NIR FPs and perform well in protein fusions, allowing multicolour structured illumination microscopy. miRFPs enable development of several types of NIR biosensors, such as for protein–protein interactions, RNA detection, signalling cascades and cell fate. We demonstrate this by engineering the monomeric fluorescence complementation reporters, the IκBα reporter for NF-κB pathway and the cell cycle biosensor for detection of proliferation status of cells in culture and in animals. miRFPs allow non-invasive visualization and detection of biological processes at different scales, from super-resolution microscopy to in vivo imaging, using the same probes. PMID:27539380

  18. Laboratory Characterization and Modeling of a Near-Infrared Enhanced Photomultiplier Tube

    NASA Technical Reports Server (NTRS)

    Biswas, A.; Farr, W. H.

    2003-01-01

    The photon-starved channel for optical communications from deep space requires the development of detector technology that can achieve photon-counting sensitivities with high bandwidth. In this article, a near-infrared enhanced photomultiplier tube (PMT) with a quantum e.ciency of 0.08 at a 1.06- m wavelength is characterized in the laboratory. A Polya distribution model is used to compute the probability distribution function of the emitted secondary photoelectrons from the PMT. The model is compared with measured pulse-height distributions with reasonable agreement. The model accounts for realistic device parameters, such as the individual dynode stage gains and a shape parameter that is representative of the spatial uniformity of response across the photocathode and dynodes. Bit-error rate (BER) measurements also are presented for 4- and 8-pulse-position modulation (PPM) modulation schemes with data rates of 20 to 30 Mb/s. A BER of 10-2 is obtained for a mean of 8 detected photons.

  19. Herschel-ATLAS: VISTA VIKING near-infrared counterparts in the Phase 1 GAMA 9-h data

    NASA Astrophysics Data System (ADS)

    Fleuren, S.; Sutherland, W.; Dunne, L.; Smith, D. J. B.; Maddox, S. J.; González-Nuevo, J.; Findlay, J.; Auld, R.; Baes, M.; Bond, N. A.; Bonfield, D. G.; Bourne, N.; Cooray, A.; Buttiglione, S.; Cava, A.; Dariush, A.; De Zotti, G.; Driver, S. P.; Dye, S.; Eales, S.; Fritz, J.; Gunawardhana, M. L. P.; Hopwood, R.; Ibar, E.; Ivison, R. J.; Jarvis, M. J.; Kelvin, L.; Lapi, A.; Liske, J.; Michałowski, M. J.; Negrello, M.; Pascale, E.; Pohlen, M.; Prescott, M.; Rigby, E. E.; Robotham, A.; Scott, D.; Temi, P.; Thompson, M. A.; Valiante, E.; van der Werf, P.

    2012-07-01

    We identify near-infrared Ks-band counterparts to Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) submillimetre (submm) sources, using a preliminary object catalogue from the VISTA Kilo-degree Infrared Galaxy (VIKING) survey. The submm sources are selected from the H-ATLAS Phase 1 catalogue of the Galaxy and Mass Assembly 9-h field, which includes all objects detected at 250, 350 or ? with the instrument. We apply and discuss a likelihood ratio method for VIKING candidates within a search radius of 10 arcsec of the 22 000 SPIRE sources with a 5σ detection at ?. We estimate the fraction of SPIRE sources with a counterpart above the magnitude limit of the VIKING survey to be Q0≈ 0.73. We find that 11 294 (51 per cent) of the SPIRE sources have a best VIKING counterpart with a reliability R≥ 0.8, and the false identification rate of these is estimated to be 4.2 per cent. We expect to miss ˜5 per cent of true VIKING counterparts. There is evidence from Z-J and J-Ks colours that the reliable counterparts to SPIRE galaxies are marginally redder than the field population. We obtain photometric redshifts for ˜68 per cent of all (non-stellar) VIKING candidates with a median redshift of ?. We have spectroscopic redshifts for 3147 (˜28 per cent) of the reliable counterparts from existing redshift surveys. Comparing to the results of the optical identifications supplied with the Phase 1 catalogue, we find that the use of medium-deep near-infrared data improves the identification rate of reliable counterparts from 36 to 51 per cent. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. VISTA is an ESO near-infrared telescope in Chile.

  20. Multifunctional calcium phosphate nano-contrast agent for combined nuclear, magnetic and near-infrared in vivo imaging.

    PubMed

    Ashokan, Anusha; Gowd, Genekehal S; Somasundaram, Vijay H; Bhupathi, Arun; Peethambaran, Reshmi; Unni, A K K; Palaniswamy, Shanmugasundaram; Nair, Shantikumar V; Koyakutty, Manzoor

    2013-09-01

    Combination of three imaging techniques such as nuclear, magnetic and near-infrared fluorescence can aid in improved diagnosis of disease by synergizing specific advantages of each of these techniques such as deep tissue penetration of radiation signals, anatomical and functional details provided by magnetic contrast and better spatial resolution of optical signals. In the present work, we report the development of a multimodal contrast agent based on calcium phosphate nanoparticles (nCP), doped with both indocyanine green (ICG) and Gadolinium (Gd(3+)), and labeled with 99m-Technetium-methylene diphosphonate ((99m)Tc-MDP) for combined optical, magnetic and nuclear imaging. In order to obtain the desired tri-modal contrast properties, the concentrations of ICG, Gd(3+) and (99m)Tc were optimized at ∼0.15wt%, 3.38at% and ∼0.002ng/mg of nCP, respectively. The leaching-out of ICG was protected by an additional coating of polyethyleneimine (PEI). Toxicological evaluation of the final construct carried out on healthy human mononuclear cells, red-blood cells and platelets, showed excellent hemocompatibility. In vivo multimodal imaging using mice models revealed the ability to provide near-infrared, magnetic and nuclear contrast simultaneously. The nanoparticles also showed the potential for improved MR based angio-imaging of liver. Retention of intravenously administrated nanoparticles in the liver was reduced with PEGylation and the clearance was observed within 48h without causing any major histological changes in vital organs. Thus, we developed a non-toxic tri-modal nano-contrast agent using calcium phosphate nanoparticles and demonstrated its potential for combined nuclear, magnetic and near-infrared imaging in vivo.

  1. Near-infrared photodetectors utilizing MoS{sub 2}-based heterojunctions

    SciTech Connect

    Park, Min Ji; Min, Jung Ki; Yi, Sum-Gyun; Kim, Joo Hyoung; Yoo, Kyung-Hwa; Oh, Jeseung

    2015-07-28

    Near-infrared photodetectors are developed using graphene/MoS{sub 2} and WSe{sub 2}/MoS{sub 2} vertical heterojunctions. These heterojunctions exhibit diode-rectifying behavior in the dark and enhanced photocurrent upon near-infrared irradiation. The photocurrent increases with increasing near-infrared power, leading to the photoresponsibility of 0.14 and 0.3 A W{sup −1} for the graphene/MoS{sub 2} and WSe{sub 2}/MoS{sub 2} heterojunctions, respectively, which are much higher than the photoresponsibility reported for a multilayer MoS{sub 2} phototransistor.

  2. Enhanced visible and near-infrared capabilities of the JET mirror-linked divertor spectroscopy system

    SciTech Connect

    Lomanowski, B. A. Sharples, R. M.; Meigs, A. G.; Conway, N. J.; Zastrow, K.-D.; Heesterman, P.; Kinna, D. [EURATOM Collaboration: JET-EFDA Team

    2014-11-15

    The mirror-linked divertor spectroscopy diagnostic on JET has been upgraded with a new visible and near-infrared grating and filtered spectroscopy system. New capabilities include extended near-infrared coverage up to 1875 nm, capturing the hydrogen Paschen series, as well as a 2 kHz frame rate filtered imaging camera system for fast measurements of impurity (Be II) and deuterium Dα, Dβ, Dγ line emission in the outer divertor. The expanded system provides unique capabilities for studying spatially resolved divertor plasma dynamics at near-ELM resolved timescales as well as a test bed for feasibility assessment of near-infrared spectroscopy.

  3. Enhanced visible and near-infrared capabilities of the JET mirror-linked divertor spectroscopy systema)

    NASA Astrophysics Data System (ADS)

    Lomanowski, B. A.; Meigs, A. G.; Conway, N. J.; Zastrow, K.-D.; Sharples, R. M.; Heesterman, P.; Kinna, D.

    2014-11-01

    The mirror-linked divertor spectroscopy diagnostic on JET has been upgraded with a new visible and near-infrared grating and filtered spectroscopy system. New capabilities include extended near-infrared coverage up to 1875 nm, capturing the hydrogen Paschen series, as well as a 2 kHz frame rate filtered imaging camera system for fast measurements of impurity (Be II) and deuterium Dα, Dβ, Dγ line emission in the outer divertor. The expanded system provides unique capabilities for studying spatially resolved divertor plasma dynamics at near-ELM resolved timescales as well as a test bed for feasibility assessment of near-infrared spectroscopy.

  4. Polymeric near-infrared absorbing dendritic nanogels for efficient in vivo photothermal cancer therapy.

    PubMed

    Molina, Maria; Wedepohl, Stefanie; Calderón, Marcelo

    2016-03-21

    In recent years, several near-infrared light absorbing inorganic nanomaterials have been developed for photothermal therapy. However, their biological fate after injection limits their clinical utilization. In this work, we developed a novel polymeric near-infrared light absorbing material based on a biocompatible thermoresponsive nanogel that is semi-interpenetrated with polyaniline, a conjugated polymer with strong near-infrared absorbance. This polymeric nanocomposite generates heat after being irradiated by NIR light, thereby inducing a local hyperthermia that is used for photothermal cancer therapy in vitro and in vivo.

  5. Design of camouflage material for visible and near infrared based on thin film technology

    NASA Astrophysics Data System (ADS)

    Miao, Lei; Shi, Jia-ming; Zhao, Da-peng; Liu, Hao; Wang, Chao; Xu, Yan-liang

    2015-11-01

    Visible light and near infrared based camouflage materials achieve good stealth under traditional optical detection equipment but its spectral differences with green plants can be taken advantage of by high spectrum based detection technologies. Based on the thin structure of bandpass filter, we designed an optical film with both green and near infrared spectrum. We conducted simulations using transfer matrix methods and optimized the result by simplex methods. The spectral reflectance curve of the proposed thin film matches that of green plants, and experiments show that the proposed thin film achieve good invisibility under visible light and near infrared in a wide viewing angle.

  6. Near-infrared Integral-Field Spectrograph (NIFS): An Instrument Proposed for Gemini

    NASA Astrophysics Data System (ADS)

    McGregor, Peter J.; Conroy, Peter; Bloxham, Gabe; van Harmelen, Jan

    1999-12-01

    In late 1998 the International Gemini Project Office identified a need for a low cost, near-infrared spectrograph to be commissioned on the Gemini South telescope on the shortest possible timescale. In response, the Research School of Astronomy and Astrophysics of the Australian National University proposed to design, construct, and commission a near-infrared, integral-field spectrograph on Gemini. The science drivers and novel design of the Near-infrared Integral-Field Spectrograph (NIFS) are described in this paper. NIFS will achieve significant economies in cost and schedule in several ways:

  7. Io in the near infrared: Near-Infrared Mapping Spectrometer (NIMS) results from the Galileo flybys in 1999 and 2000

    USGS Publications Warehouse

    Lopes, R.M.C.; Kamp, L.W.; Doute, S.; Smythe, W.D.; Carlson, R.W.; McEwen, A.S.; Geissler, P.E.; Kieffer, S.W.; Leader, F.E.; Davies, A.G.; Barbinis, E.; Mehlman, R.; Segura, M.; Shirley, J.; Soderblom, L.A.

    2001-01-01

    Galileo's Near-Infrared Mapping Spectrometer (NIMS) observed Io during the spacecraft's three flybys in October 1999, November 1999, and February 2000. The observations, which are summarized here, were used to map the detailed thermal structure of active volcanic regions and the surface distribution of SO2 and to investigate the origin of a yet unidentified compound showing an absorption feature at ???1 ??m. We present a summary of the observations and results, focusing on the distribution of thermal emission and of SO2 deposits. We find high eruption temperatures, consistent with ultramafic volcanism, at Pele. Such temperatures may be present at other hot spots, but the hottest areas may be too small for those temperatures to be detected at the spatial resolution of our observations. Loki is the site of frequent eruptions, and the low thermal emission may represent lavas cooling on the caldera's surface or the cooling crust of a lava lake. High-resolution spectral observations of Emakong caldera show thermal emission and SO2 within the same pixels, implying that patches of SO2 frost and patches of cooling lavas or sulfur flows are present within a few kilometers from one another. Thermal maps of Prometheus and Amirani show that these two hot spots are characterized by long lava flows. The thermal profiles of flows at both locations are consistent with insulated flows, with the Amirani flow field having more breakouts of fresh lava along its length. Prometheus and Amirani each show a white ring at visible wavelengths, while SO2 distribution maps show that the highest concentration of SO2 in both ring deposits lies outside the white portion. Visible measurements at high phase angles show that the white deposit around Prometheus extends into the SO2 ring. This suggests that the deposits are thin and that compositional or grain size variations may occur in the radial direction. SO2 mapping of the Chaac region shows that the interior of a caldera adjacent to Chaac has

  8. Polarization disks in near-infrared high-resolution imaging

    NASA Astrophysics Data System (ADS)

    Murakawa, K.

    2010-07-01

    A polarization disk is a characteristic feature of optical and near-infrared (NIR) polarimetric images of young stellar objects (YSOs) and is regarded as convincing evidence that a dust disk is present. We analyze high-resolution linear polarization maps of a sample of low-mass YSO disk models by means of radiative transfer calculations to investigate the effects of the disk geometry and grain sizes on polarization properties. Our modeling assumes spherical grains with a power-law size distribution of n(a)∝ a-3.5; 0.005 μm ≤ a ≤ a_max and with a fixed a_max of 0.25 μm for the outer envelope and a different a_max for the disk. The parameters to examine are the disk height (i.e. the ratio of the disk height to the outer disk radius H of 0.1 to 1.0) and the dust sizes in the disk (i.e. a_max of 0.25 to 1000.0 μm). In a near pole-on view, the polarization vectors are centro-symmetrically aligned even towards the disk, but the degree of polarization can be different from the envelope. We predict that the pole-on disk can be distinguished from the envelope. In contrast, the model images show a bipolar nebulosity and a polarization disk with a vector alignment in edge-on view. The polarization is low (<10%) for large grains or low H values and high (up to ~80%) for small grains and high H values. In contrast, comparably constant polarizations (20-40%) are obtained in the optical. The wavelength dependence in low NIR polarization cases is often detected in many T Tauri stars, suggesting that grain growth or an advanced disk accretion is expected in these objects. The opposite trend in high NIR polarization cases, which is found in some low-mass protostars, is reproduced with spherical grain models. To understand our results, we developed a generalized scattering model, which is an extension of the vector alignment mechanism. In the low-mass star disk case, multiple-scattered light behaves as if it chooses paths of comparably low optical density region (e.g. the

  9. Porphyrin Based Near Infrared-Absorbing Materials for Organic Photovoltaics

    NASA Astrophysics Data System (ADS)

    Zhong, Qiwen

    The conservation and transformation of energy is essential to the survival of mankind, and thus concerns every modern society. Solar energy, as an everlasting source of energy, holds one of the key solutions to some of the most urgent problems the world now faces, such as global warming and the oil crisis. Advances in technologies utilizing clean, abundant solar energy, could be the steering wheel of our societies. Solar cells, one of the major advances in converting solar energy into electricity, are now capturing people's interest all over the globe. While solar cells have been commercially available for many years, the manufacturing of solar cells is quite expensive, limiting their broad based implementation. The cost of solar cell based electricity is 15-50 cents per kilowatt hour (¢/kwh), depending on the type of solar cell, compared to 0.7 ¢/kwh for fossil fuel based electricity. Clearly, decreasing the cost of electricity from solar cells is critical for their wide spread deployment. This will require a decrease in the cost of light absorbing materials and material processing used in fabricating the cells. Organic photovoltaics (OPVs) utilize organic materials such as polymers and small molecules. These devices have the advantage of being flexible and lower cost than conventional solar cells built from inorganic semiconductors (e.g. silicon). The low cost of OPVs is tied to lower materials and fabrication costs of organic cells. However, the current power conversion efficiencies of OPVs are still below 15%, while convention crystalline Si cells have efficiencies of 20-25%. A key limitation in OPVs today is their inability to utilize the near infrared (NIR) portion of the solar spectrum. This part of the spectrum comprises nearly half of the energy in sunlight that could be used to make electricity. The first and foremost step in conversion solar energy conversion is the absorption of light, which nature has provided us optimal model of, which is

  10. Near-infrared instrumentation for rapid-response astronomy

    NASA Astrophysics Data System (ADS)

    Capone, John Isaac

    gamma-ray bursts (GRBs) are the Universe's most luminous transient events. Since the discovery of GRBs was announced in 1973, efforts have been ongoing to obtain data over a broader range of the electromagnetic spectrum at the earliest possible times following the initial detection. The discovery of the theorized "afterglow'' emission in radio through X-ray bands in the late 1990s confirmed the cosmological nature of these events. At present, GRB afterglows are among the best probes of the early Universe (z ≥ 9). In addition to informing theories about GRBs themselves, observations of afterglows probe the circum-burst medium (CBM), properties of the host galaxies and the progress of cosmic reionization. To explore the early-time variability of afterglows, I have developed a generalized analysis framework which models near-infrared (NIR), optical, ultra-violet (UV) and X-ray light curves without assuming an underlying model. These fits are then used to construct the spectral energy distribution (SED) of afterglows at arbitrary times within the observed window. Physical models are then used to explore the evolution of the SED parameter space with time. I demonstrate that this framework produces evidence of the photodestruction of dust in the CBM of GRB 120119A, similar to the findings from a previous study of this afterglow. The framework is additionally applied to the afterglows of GRB 140419A and GRB 080607. In these cases the evolution of the SEDs appears consistent with the standard fireball model. Having introduced the scientific motivations for early-time observations, I introduce the Rapid Infrared Imager-Spectrometer (RIMAS). Once commissioned on the 4.3 meter Discovery Channel Telescope (DCT), RIMAS will be used to study the afterglows of GRBs through photometric and spectroscopic observations beginning within minutes of the initial burst. The instrument will operate in the NIR, from 0.97 microm to 2.37 microm, permitting the detection of very high

  11. Nonlinear femtosecond near infrared laser structuring in oxide glasses

    NASA Astrophysics Data System (ADS)

    Royon, Arnaud

    Three-dimensional femtosecond laser structuring has a growing interest because of its ease of implementation and the numerous possible applications in the domain of photonic components. Structures such as waveguides, diffraction gratings, optical memories or photonic crystals can be fabricated thanks to this technique. Its use with oxide glasses is promising because of several advantages; they are resistant to flux and ageing, their chemical composition can easily be changed to fit the well-defined requirements of an application. They can already be found in Raman amplifiers, optical fibers, fiber lasers, and other devices. This thesis is based on two axes. The first axis consists in characterizing the linear and nonlinear optical properties of bulk vitreous materials in order to optimize their composition with a particular application in view. Within this context, the nonlinear optical properties, their physical origins (electronic and nuclear) as well as their characteristic response times (from a few femtoseconds to a few hundreds of picoseconds) are described within the Born-Oppenheimer approximation. Fused silica and several sodium-borophosphate glasses containing different concentrations in niobium oxide have been studied. Results show that the nonlinear optical properties of fused silica are mainly from electronic origin, whereas in the sodium-borophosphate glasses, the contribution from nuclear origin becomes predominant when the concentration of niobium oxide exceeds 30%. The second axis is based on the structuring of materials. Three commercially available fused silica samples presenting different fabrication conditions (therefore distinct impurity levels) and irradiated with a near infrared femtosecond laser have been studied. The laser induced defects have been identified by means of several spectroscopic techniques. They show the formation of color centers as well as a densification inside the irradiated area. Their linear refractive index and

  12. Near-Infrared spectroscopy of the possible nova candidate PNV J17355050-2934240

    NASA Astrophysics Data System (ADS)

    Srivastava, Mudit; Joshi, Vishal; Banerjee, D. P. K.; Ashok, N. M.

    2016-03-01

    We report near-infrared observations of PNV J17355050-2934240 which has been reported as a possible nova candidate in the CBAT TOCP site (http://www.cbat.eps.harvard.edu/unconf/followups/J17355050-2934240.html).

  13. A NEW GAS CELL FOR HIGH-PRECISION DOPPLER MEASUREMENTS IN THE NEAR-INFRARED

    SciTech Connect

    Valdivielso, L.; Maukonen, D.; Peale, R. E.

    2010-06-01

    High-resolution spectroscopy in the near-infrared could become the leading method for discovering extra-solar planets around very low mass stars and brown dwarfs. In order to help to achieve an accuracy of {approx}m s{sup -1}, we are developing a gas cell which consists of a mixture of gases whose absorption spectral lines span all over the near-infrared region. We present the most promising mixture, made of acetylene, nitrous oxide, ammonia, chloromethanes, and hydrocarbons. The mixture is contained in a small size 13 cm long gas cell and covers most of the H and K bands. It also shows small absorptions in the J band, but they are few and not sharp enough for near-infrared wavelength calibration. We describe the working method and experiments, and compare our results with the state of the art for near-infrared gas cells.

  14. Near infrared spectroscopy and chemometrics analysis of complex traits in animal physiology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Near infrared reflectance (NIR) applications have been expanding from the traditional framework of small molecule chemical purity and composition (as defined by spectral libraries) to complex system analysis and holistic exploratory approaches to questions in biochemistry, biophysics and environment...

  15. Prediction of maize seed attributes using a rapid single kernel near infrared instrument

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non-destructive measurements of seed attributes would significantly enhance breeder selection of seeds with specific traits and potentially improve hybrid development. A single kernel near infrared reflectance (NIR) instrument was developed for rapidly predicting maize grain attributes, which would ...

  16. Application of Near Infrared (NIR) Spectroscopy to Peanut Grading and Quality Analysis: Overview

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Techniques using near infrared (NIR) spectroscopy for quality measurements are becoming more popular in food processing and quality inspection of agricultural commodities. NIR spectroscopy has several advantages over conventional physical and chemical analytical methods of food quality analysis. It ...

  17. Measurement of single soybean seed attributes by near infrared technologies. A comparative study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four near infrared spectrophotometers, and their associated spectral collection methods, were tested and compared for measuring three soybean single seed attributes: weight (g), protein (%), and oil (%). Using partial least squares (PLS) and 4 preprocessing methods, the attribute which was significa...

  18. Near-infrared emitting ytterbium metal-organic frameworks with tunable excitation properties.

    PubMed

    White, Kiley A; Chengelis, Demetra A; Zeller, Matthias; Geib, Steven J; Szakos, Jessica; Petoud, Stéphane; Rosi, Nathaniel L

    2009-08-14

    The design of metal-organic frameworks (MOFs) incorporating near-infrared emitting ytterbium cations and organic sensitizers allows for the preparation of new materials with tunable and enhanced photophysical properties.

  19. GQ Lup Ab Visible & Near-Infrared Photometric Analysis

    SciTech Connect

    Marois, C; Macintosh, B; Barman, T

    2006-08-07

    We have re-analyzed archival HST R and I band images and Subaru CH{sub 4}, H, Ks and L{prime} data of the recently discovered planetary mass companion (PMC) GQ Lup Ab. With these we produce the first R and I band photometry of the companion and fit a radius and effective temperature using detailed model atmospheres. We find an effective temperature of 2338 {+-} 100K, and a radius of 0.37 {+-} 0.05R{sub {circle_dot}} and luminosity of log(L/L{sub {circle_dot}}) = -2.43 {+-} 0.07 (at 140pc). Since we fit wavelengths that span most of the emitted radiation from GQ Lup this luminosity estimate is robust, with uncertainty dominated by the distance uncertainty. The radius obtained for 140pc (0.37R{sub {circle_dot}}) is significantly larger than the one originally derived. The mass of the object is much more model-dependent than the radiative properties, but for the GAIA dusty models we find a mass between 9-20 M{sub Jup}, in the range of the brown dwarf and PMC deuterium burning boundary. Assuming a distance of 140pc, observations fit to 1{sigma} the Baraffe evolution model for a {approx} 15 M{sub Jup} brown dwarf. Additionally, the F606W photometric band is significantly overluminous compared to model predictions. Such overluminosity could be explained by a bright H{alpha} emission from chromospheric activity, interaction with another undetected companion, or accretion. Assuming that GQ Lup Ab has a bright H{alpha} emission line, its H{alpha} emission strength is 10{sup -1.71 {+-} 0.10} L{sub bol}, significantly larger than field late-type dwarfs. GQ Lup Ab might be strongly accreting and still be in its formation phase.

  20. Quantitative Measurements of Daytime Near Infrared Sky Brightness at the AEOS 3.6 m Telescope

    DTIC Science & Technology

    2014-09-01

    Quantitative measurements of daytime near infrared sky brightness at the AEOS 3.6 m telescope Michael Hart, Stuart Jefferies Douglas Hope, James...HI 96753 ABSTRACT We report daytime sky brightness measurements recorded in the near infrared from the 3.6 m AEOS telescope . Measurements were made...techniques for high-resolution imaging of satellites from the AEOS telescope . 1 MOTIVATION At first glance it would appear that imaging in the near