Prime Focus Spectrograph: A very wide-field, massively multiplexed, optical & near-infrared spectrograph for Subaru Telescope

NASA Astrophysics Data System (ADS)

TAMURA, NAOYUKI

2015-08-01

PFS (Prime Focus Spectrograph), a next generation facility instrument on Subaru, is a very wide-field, massively-multiplexed, and optical & near-infrared spectrograph. Exploiting the Subaru prime focus, 2400 reconfigurable fibers will be distributed in the 1.3 degree field. The spectrograph will have 3 arms of blue, red, and near-infrared cameras to simultaneously observe spectra from 380nm to 1260nm at one exposure. The development of this instrument has been undertaken by the international collaboration at the initiative of Kavli IPMU. The project is now going into the construction phase aiming at system integration and on-sky commissioning in 2017-2018, and science operation in 2019. In parallel, the survey design has also been developed envisioning a Subaru Strategic Program (SSP) that spans roughly speaking 300 nights over 5 years. The major science areas are three-folds: Cosmology, galaxy/AGN evolution, and Galactic archaeology (GA). The cosmology program will be to constrain the nature of dark energy via a survey of emission line galaxies over a comoving volume of ~10 Gpc^3 in the redshift range of 0.8 < z < 2.4. In the GA program, radial velocities and chemical abundances of stars in the Milky Way, dwarf spheroidal galaxies, and M31 will be used to understand the past assembly histories of those galaxies and the structures of their dark matter halos. Spectra will be taken for ~1 million stars as faint as V = 22 therefore out to large distances from the Sun. For the extragalactic program, our simulations suggest the wide wavelength coverage of PFS will be particularly powerful in probing the galaxy populations and its clustering properties over a wide redshift range. We will conduct a survey of color-selected 1 < z < 2 galaxies and AGN over 20 square degrees down to J = 23.4, yielding a fair sample of galaxies with stellar masses above ˜10^10 solar masses. Further, PFS will also provide unique spectroscopic opportunities even in the era of Euclid, LSST

WFIRST: Science from Deep Field Surveys

NASA Astrophysics Data System (ADS)

Koekemoer, Anton M.; Foley, Ryan; WFIRST Deep Field Working Group

2018-06-01

WFIRST will enable deep field imaging across much larger areas than those previously obtained with Hubble, opening up completely new areas of parameter space for extragalactic deep fields including cosmology, supernova and galaxy evolution science. The instantaneous field of view of the Wide Field Instrument (WFI) is about 0.3 square degrees, which would for example yield an Ultra Deep Field (UDF) reaching similar depths at visible and near-infrared wavelengths to that obtained with Hubble, over an area about 100-200 times larger, for a comparable investment in time. Moreover, wider fields on scales of 10-20 square degrees could achieve depths comparable to large HST surveys at medium depths such as GOODS and CANDELS, and would enable multi-epoch supernova science that could be matched in area to LSST Deep Drilling fields or other large survey areas. Such fields may benefit from being placed on locations in the sky that have ancillary multi-band imaging or spectroscopy from other facilities, from the ground or in space. The WFIRST Deep Fields Working Group has been examining the science considerations for various types of deep fields that may be obtained with WFIRST, and present here a summary of the various properties of different locations in the sky that may be considered for future deep fields with WFIRST.

WFIRST: Science from Deep Field Surveys

NASA Astrophysics Data System (ADS)

Koekemoer, Anton; Foley, Ryan; WFIRST Deep Field Working Group

2018-01-01

WFIRST will enable deep field imaging across much larger areas than those previously obtained with Hubble, opening up completely new areas of parameter space for extragalactic deep fields including cosmology, supernova and galaxy evolution science. The instantaneous field of view of the Wide Field Instrument (WFI) is about 0.3 square degrees, which would for example yield an Ultra Deep Field (UDF) reaching similar depths at visible and near-infrared wavelengths to that obtained with Hubble, over an area about 100-200 times larger, for a comparable investment in time. Moreover, wider fields on scales of 10-20 square degrees could achieve depths comparable to large HST surveys at medium depths such as GOODS and CANDELS, and would enable multi-epoch supernova science that could be matched in area to LSST Deep Drilling fields or other large survey areas. Such fields may benefit from being placed on locations in the sky that have ancillary multi-band imaging or spectroscopy from other facilities, from the ground or in space. The WFIRST Deep Fields Working Group has been examining the science considerations for various types of deep fields that may be obtained with WFIRST, and present here a summary of the various properties of different locations in the sky that may be considered for future deep fields with WFIRST.

The second Herschel-ATLAS Data Release - III. Optical and near-infrared counterparts in the North Galactic Plane field

NASA Astrophysics Data System (ADS)

Furlanetto, C.; Dye, S.; Bourne, N.; Maddox, S.; Dunne, L.; Eales, S.; Valiante, E.; Smith, M. W.; Smith, D. J. B.; Ivison, R. J.; Ibar, E.

2018-05-01

This paper forms part of the second major public data release of the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS). In this work, we describe the identification of optical and near-infrared counterparts to the submillimetre detected sources in the 177 deg2 North Galactic Plane (NGP) field. We used the likelihood ratio method to identify counterparts in the Sloan Digital Sky Survey and in the United Kingdom InfraRed Telescope Imaging Deep Sky Survey within a search radius of 10 arcsec of the H-ATLAS sources with a 4σ detection at 250 μm. We obtained reliable (R ≥ 0.8) optical counterparts with r < 22.4 for 42 429 H-ATLAS sources (37.8 per cent), with an estimated completeness of 71.7 per cent and a false identification rate of 4.7 per cent. We also identified counterparts in the near-infrared using deeper K-band data which covers a smaller ˜25 deg2. We found reliable near-infrared counterparts to 61.8 per cent of the 250-μm-selected sources within that area. We assessed the performance of the likelihood ratio method to identify optical and near-infrared counterparts taking into account the depth and area of both input catalogues. Using catalogues with the same surface density of objects in the overlapping ˜25 deg2 area, we obtained that the reliable fraction in the near-infrared (54.8 per cent) is significantly higher than in the optical (36.4 per cent). Finally, using deep radio data which covers a small region of the NGP field, we found that 80-90 per cent of our reliable identifications are correct.

Graphene-enhanced infrared near-field microscopy.

PubMed

Li, Peining; Wang, Tao; Böckmann, Hannes; Taubner, Thomas

2014-08-13

Graphene is a promising two-dimensional platform for widespread nanophotonic applications. Recent theories have predicted that graphene can also enhance evanescent fields for subdiffraction-limited imaging. Here, for the first time we experimentally demonstrate that monolayer graphene offers a 7-fold enhancement of evanescent information, improving conventional infrared near-field microscopy to resolve buried structures at a 500 nm depth with λ/11-resolution.

Far Infrared Synchrotron Near-Field Nanoimaging and Nanospectroscopy

DOE PAGES

Khatib, Omar; Bechtel, Hans A.; Martin, Michael C.; ...

2018-05-11

Here, scattering scanning near-field optical microscopy (s-SNOM) has emerged as a powerful imaging and spectroscopic tool for investigating nanoscale heterogeneities in biology, quantum matter, and electronic and photonic devices. However, many materials are defined by a wide range of fundamental molecular and quantum states at far-infrared (FIR) resonant frequencies currently not accessible by s-SNOM. Here we show ultrabroadband FIR s-SNOM nanoimaging and spectroscopy by combining synchrotron infrared radiation with a novel fast and low-noise copper-doped germanium (Ge:Cu) photoconductive detector. This approach of FIR synchrotron infrared nanospectroscopy (SINS) extends the wavelength range of s-SNOM to 31 μm (320 cm –1, 9.7more » THz), exceeding conventional limits by an octave to lower energies. We demonstrate this new nanospectroscopic window by measuring elementary excitations of exemplary functional materials, including surface phonon polariton waves and optical phonons in oxides and layered ultrathin van der Waals materials, skeletal and conformational vibrations in molecular systems, and the highly tunable plasmonic response of graphene.« less

Far Infrared Synchrotron Near-Field Nanoimaging and Nanospectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khatib, Omar; Bechtel, Hans A.; Martin, Michael C.

Here, scattering scanning near-field optical microscopy (s-SNOM) has emerged as a powerful imaging and spectroscopic tool for investigating nanoscale heterogeneities in biology, quantum matter, and electronic and photonic devices. However, many materials are defined by a wide range of fundamental molecular and quantum states at far-infrared (FIR) resonant frequencies currently not accessible by s-SNOM. Here we show ultrabroadband FIR s-SNOM nanoimaging and spectroscopy by combining synchrotron infrared radiation with a novel fast and low-noise copper-doped germanium (Ge:Cu) photoconductive detector. This approach of FIR synchrotron infrared nanospectroscopy (SINS) extends the wavelength range of s-SNOM to 31 μm (320 cm –1, 9.7more » THz), exceeding conventional limits by an octave to lower energies. We demonstrate this new nanospectroscopic window by measuring elementary excitations of exemplary functional materials, including surface phonon polariton waves and optical phonons in oxides and layered ultrathin van der Waals materials, skeletal and conformational vibrations in molecular systems, and the highly tunable plasmonic response of graphene.« less

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

Artist Concept of Wide-field Infrared Survey Explorer WISE

NASA Image and Video Library

2004-10-08

Artist concept of Wide-field Infrared Survey Explorer. A new NASA mission will scan the entire sky in infrared light in search of nearby cool stars, planetary construction zones and the brightest galaxies in the universe. http://photojournal.jpl.nasa.gov/catalog/PIA06927

[Application of near infrared spectroscopy technology (NIRS) in forage field].

PubMed

Yan, Xu; Bai, Shi-Qie; Yan, Jia-Jun; Gan, You-Min; Dao, Zhi-Xue

2012-07-01

The majority of nutrients in ruminants and other herbivores come from forages. Forage quality not only affects the growth and production efficiency of livestock, but also determines the final output and quality of livestock products. Forage quality mainly depends on nutrient concentrations and their digestibility, palatability and the level of presence of antiquality factors and mycotoxins in forage. Near infrared reflectance spectroscopy (NIRS) has been widely used in many research areas because it is a inexpensive, rapid, simple and nondestructive technique offering the potential for qualitative and quantitative analysis. The present paper briefly introduces the principle and characteristics of NIRS, detailedly expounds the application of NIRS in forage quality. In addition, other applications of near infrared spectroscopy technique in forage are also discussed, including forage breeding, identification of variety and classification by kind. This paper comprehensively reviews the status quo of application of NIRS in forage filed, in order to contribute to promoting development of NIRS in this field in China.

Final Optical Design of PANIC, a Wide-Field Infrared Camera for CAHA

NASA Astrophysics Data System (ADS)

Cárdenas, M. C.; Gómez, J. Rodríguez; Lenzen, R.; Sánchez-Blanco, E.

We present the Final Optical Design of PANIC (PAnoramic Near Infrared camera for Calar Alto), a wide-field infrared imager for the Ritchey-Chrtien focus of the Calar Alto 2.2 m telescope. This will be the first instrument built under the German-Spanish consortium that manages the Calar Alto observatory. The camera optical design is a folded single optical train that images the sky onto the focal plane with a plate scale of 0.45 arcsec per 18 μm pixel. The optical design produces a well defined internal pupil available to reducing the thermal background by a cryogenic pupil stop. A mosaic of four detectors Hawaii 2RG of 2 k ×2 k, made by Teledyne, will give a field of view of 31.9 arcmin ×31.9 arcmin.

MID-INFRARED SELECTION OF ACTIVE GALACTIC NUCLEI WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER. I. CHARACTERIZING WISE-SELECTED ACTIVE GALACTIC NUCLEI IN COSMOS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stern, Daniel; Assef, Roberto J.; Eisenhardt, Peter

2012-07-01

The Wide-field Infrared Survey Explorer (WISE) is an extremely capable and efficient black hole finder. We present a simple mid-infrared color criterion, W1 - W2 {>=} 0.8 (i.e., [3.4]-[4.6] {>=}0.8, Vega), which identifies 61.9 {+-} 5.4 active galactic nucleus (AGN) candidates per deg{sup 2} to a depth of W2 {approx} 15.0. This implies a much larger census of luminous AGNs than found by typical wide-area surveys, attributable to the fact that mid-infrared selection identifies both unobscured (type 1) and obscured (type 2) AGNs. Optical and soft X-ray surveys alone are highly biased toward only unobscured AGNs, while this simple WISEmore » selection likely identifies even heavily obscured, Compton-thick AGNs. Using deep, public data in the COSMOS field, we explore the properties of WISE-selected AGN candidates. At the mid-infrared depth considered, 160 {mu}Jy at 4.6 {mu}m, this simple criterion identifies 78% of Spitzer mid-infrared AGN candidates according to the criteria of Stern et al. and the reliability is 95%. We explore the demographics, multiwavelength properties and redshift distribution of WISE-selected AGN candidates in the COSMOS field.« less

Near-infrared deep brain stimulation via upconversion nanoparticle–mediated optogenetics

NASA Astrophysics Data System (ADS)

Chen, Shuo; Weitemier, Adam Z.; Zeng, Xiao; He, Linmeng; Wang, Xiyu; Tao, Yanqiu; Huang, Arthur J. Y.; Hashimotodani, Yuki; Kano, Masanobu; Iwasaki, Hirohide; Parajuli, Laxmi Kumar; Okabe, Shigeo; Teh, Daniel B. Loong; All, Angelo H.; Tsutsui-Kimura, Iku; Tanaka, Kenji F.; Liu, Xiaogang; McHugh, Thomas J.

2018-02-01

Optogenetics has revolutionized the experimental interrogation of neural circuits and holds promise for the treatment of neurological disorders. It is limited, however, because visible light cannot penetrate deep inside brain tissue. Upconversion nanoparticles (UCNPs) absorb tissue-penetrating near-infrared (NIR) light and emit wavelength-specific visible light. Here, we demonstrate that molecularly tailored UCNPs can serve as optogenetic actuators of transcranial NIR light to stimulate deep brain neurons. Transcranial NIR UCNP-mediated optogenetics evoked dopamine release from genetically tagged neurons in the ventral tegmental area, induced brain oscillations through activation of inhibitory neurons in the medial septum, silenced seizure by inhibition of hippocampal excitatory cells, and triggered memory recall. UCNP technology will enable less-invasive optical neuronal activity manipulation with the potential for remote therapy.

Near infrared photographic sky survey - A field index

NASA Technical Reports Server (NTRS)

Rossano, G. S.; Craine, E. R.

1980-01-01

The book presents an index of previously cataloged objects located in the fields of the northern sky included in the Steward Observatory Near Infrared Photographic Sky Survey, which was intended to be used for identification purposes in an effort to locate extremely red objects. The objects included in the index were taken from 16 catalogs of bright nebulae, dark nebulae, infrared objects, reflection nebulae, supernova remnants and other objects, and appear with their corresponding field numbers, computed field center coordinates, object name and 1950 epoch equatorial coordinates, as well as supplementary descriptive information as available. An appendix is also provided in which the center coordinates of each field are listed.

Wide-Field Infrared Survey Telescope (WFIRST) Integrated Modeling

NASA Technical Reports Server (NTRS)

Liu, Kuo-Chia; Blaurock, Carl

2017-01-01

Contents: introduction to WFIRST (Wide-Field Infrared Survey Telescope) and integrated modeling; WFIRST stability requirement summary; instability mitigation strategies; dynamic jitter results; STOP (structural-thermal-optical performance) (thermal distortion) results; STOP and jitter capability limitations; model validation philosophy.

Near-infrared Thermal Emission Detections of a Number of Hot Jupiters and the Systematics of Ground-based Near-infrared Photometry

NASA Astrophysics Data System (ADS)

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

2015-03-01

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 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. Based on observations obtained with WIRCam, a joint project of Canada-France-Hawaii Telescope (CFHT), Taiwan, Korea, Canada, France, at the CFHT, which is operated by the National Research Council (NRC) of Canada, the Institute National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

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. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Resonant antenna probes for tip-enhanced infrared near-field microscopy.

PubMed

Huth, Florian; Chuvilin, Andrey; Schnell, Martin; Amenabar, Iban; Krutokhvostov, Roman; Lopatin, Sergei; Hillenbrand, Rainer

2013-03-13

We report the development of infrared-resonant antenna probes for tip-enhanced optical microscopy. We employ focused-ion-beam machining to fabricate high-aspect ratio gold cones, which replace the standard tip of a commercial Si-based atomic force microscopy cantilever. Calculations show large field enhancements at the tip apex due to geometrical antenna resonances in the cones, which can be precisely tuned throughout a broad spectral range from visible to terahertz frequencies by adjusting the cone length. Spectroscopic analysis of these probes by electron energy loss spectroscopy, Fourier transform infrared spectroscopy, and Fourier transform infrared near-field spectroscopy corroborates their functionality as resonant antennas and verifies the broad tunability. By employing the novel probes in a scattering-type near-field microscope and imaging a single tobacco mosaic virus (TMV), we experimentally demonstrate high-performance mid-infrared nanoimaging of molecular absorption. Our probes offer excellent perspectives for optical nanoimaging and nanospectroscopy, pushing the detection and resolution limits in many applications, including nanoscale infrared mapping of organic, molecular, and biological materials, nanocomposites, or nanodevices.

Broadband near-field infrared spectroscopy with a high temperature plasma light source.

PubMed

Lahneman, D J; Huffman, T J; Xu, Peng; Wang, S L; Grogan, T; Qazilbash, M M

2017-08-21

Scattering-type scanning near-field optical microscopy (S-SNOM) has enormous potential as a spectroscopy tool in the infrared spectral range where it can probe phonon resonances and carrier dynamics at the nanometer lengths scales. However, its applicability is limited by the lack of practical and affordable table-top light sources emitting intense broadband infrared radiation in the 100 cm -1 to 2,500 cm -1 spectral range. This paper introduces a high temperature plasma light source that is both ultra-broadband and has much more radiant power in the infrared spectral range than conventional, table-top thermal light sources such as the globar. We implement this plasma lamp in our near-field optical spectroscopy set up and demonstrate its capability as a broadband infrared nano-spectroscopy light source by obtaining near-field infrared amplitude and phase spectra of the phonon resonances of SiO 2 and SrTiO 3 .

A Near IR Fabry-Perot Interferometer for Wide Field, Low Resolution Hyperspectral Imaging on the Next Generation Space Telescope

NASA Technical Reports Server (NTRS)

Barry, R. K.; Satyapal, S.; Greenhouse, M. A.; Barclay, R.; Amato, D.; Arritt, B.; Brown, G.; Harvey, V.; Holt, C.; Kuhn, J.

2000-01-01

We discuss work in progress on a near-infrared tunable bandpass filter for the Goddard baseline wide field camera concept of the Next Generation Space Telescope (NGST) Integrated Science Instrument Module (ISIM). This filter, the Demonstration Unit for Low Order Cryogenic Etalon (DULCE), is designed to demonstrate a high efficiency scanning Fabry-Perot etalon operating in interference orders 1 - 4 at 30K with a high stability DSP based servo control system. DULCE is currently the only available tunable filter for lower order cryogenic operation in the near infrared. In this application, scanning etalons will illuminate the focal plane arrays with a single order of interference to enable wide field lower resolution hyperspectral imaging over a wide range of redshifts. We discuss why tunable filters are an important instrument component in future space-based observatories.

Simulations of deep galaxy fields. 1: Monte Carlo simulations of optical and near-infrared counts

NASA Technical Reports Server (NTRS)

Chokshi, Arati; Lonsdale, Carol J.; Mazzei, Paola; De Zotti, Gianfranco

1994-01-01

Monte Carlo simulations of three-dimensional galaxy distributions are performed, following the 1988 prescription of Chokshi & Wright, to study the photometric properties of evolving galaxy populations in the optical and near-infrared bands to high redshifts. In this paper, the first of a series, we present our baseline model in which galaxy numbers are conserved, and in which no explicit 'starburst' population is included. We use the model in an attempt to simultaneously fit published blue and near-infrared photometric and spectroscopic observations of deep fields. We find that our baseline models, with a formation redshift, z(sub f), of 1000, and H(sub 0) = 50, are able to reproduce the blue counts to b(sub j) = 22, independent of the value of Omega(sub 0), and also to provide a satisfactory fit to the observed blue-band redshift distributions, but for no value of Omega(sub 0) do we achieve an acceptable fit to the fainter blue counts. In the K band, we fit the number counts to the limit of the present-day surveys only for an Omega(sub 0) = 0 cosmology. We investigate the effect on the model fits of varying the cosmological parameters H(sub 0), the formation red-shift z(sub f), and the local luminosity function. Changing H(sub 0) does not improve the fits to the observations. However, reducing the epoch of a galaxy formation used in our simulations has a substantial effect. In particular, a model with z(sub f) approximately equal to 5 in a low Omega(sub 0) universe improves the fit to the faintest photometric blue data without any need to invoke a new population of galaxies, substantial merging, or a significant starburst galaxy population. For an Omega(sub 0) = 1 universe, however, reducing z(sub f) is less successful at fitting the blue-band counts and has little effect at all at K. Varying the parameters of the local luminosity function can also have a significant effect. In particular the steep low end slope of the local luminosity function of Franceschini et

Near-field infrared vibrational dynamics and tip-enhanced decoherence.

PubMed

Xu, Xiaoji G; Raschke, Markus B

2013-04-10

Ultrafast infrared spectroscopy can reveal the dynamics of vibrational excitations in matter. In its conventional far-field implementation, however, it provides only limited insight into nanoscale sample volumes due to insufficient spatial resolution and sensitivity. Here, we combine scattering-scanning near-field optical microscopy (s-SNOM) with femtosecond infrared vibrational spectroscopy to characterize the coherent vibrational dynamics of a nanoscopic ensemble of C-F vibrational oscillators of polytetrafluoroethylene (PTFE). The near-field mode transfer between the induced vibrational molecular coherence and the metallic scanning probe tip gives rise to a tip-mediated radiative IR emission of the vibrational free-induction decay (FID). By increasing the tip–sample coupling, we can enhance the vibrational dephasing of the induced coherent vibrational polarization and associated IR emission, with dephasing times up to T2(NF) is approximately equal to 370 fs in competition against the intrinsic far-field lifetime of T2(FF) is approximately equal to 680 fs as dominated by nonradiative damping. Near-field antenna-coupling thus provides for a new way to modify vibrational decoherence. This approach of ultrafast s-SNOM enables the investigation of spatiotemporal dynamics and correlations with nanometer spatial and femtosecond temporal resolution.

Infrared spectroscopic near-field mapping of single nanotransistors.

PubMed

Huber, A J; Wittborn, J; Hillenbrand, R

2010-06-11

We demonstrate the application of scattering-type scanning near-field optical microscopy (s-SNOM) for infrared (IR) spectroscopic material recognition in state-of-the-art semiconductor devices. In particular, we employ s-SNOM for imaging of industrial CMOS transistors with a resolution better than 20 nm, which allows for the first time IR spectroscopic recognition of amorphous SiO(2) and Si(3)N(4) components in a single transistor device. The experimentally recorded near-field spectral signature of amorphous SiO(2) shows excellent agreement with model calculations based on literature dielectric values, verifying that the characteristic near-field contrasts of SiO(2) stem from a phonon-polariton resonant near-field interaction between the probing tip and the SiO(2) nanostructures. Local material recognition by s-SNOM in combination with its capabilities of contact-free and non-invasive conductivity- and strain-mapping makes IR near-field microscopy a versatile metrology technique for nanoscale material characterization and semiconductor device analysis with application potential in research and development, failure analysis and reverse engineering.

Electric field detection of phase-locked near-infrared pulses using photoconductive antenna.

PubMed

Katayama, I; Akai, R; Bito, M; Matsubara, E; Ashida, M

2013-07-15

We have demonstrated that a photoconductive antenna gated with 5-fs ultrashort laser pulses can detect electric field transients of near-infrared pulses at least up to 180 THz. Measured sensitivity spectrum of the antenna shows a good agreement with a simple calculation, demonstrating the promising capability of the antenna to near infrared spectroscopy. Using this setup, near-infrared time-domain spectroscopy and characterization of phase controlled near-infrared pulses are demonstrated. Observed absorption spectrum of a polystyrene film and complex refractive index dispersion of a fused silica plate both agree well with those obtained by the conventional methods.

Infrared Testing of the Wide-field Infrared Survey Telescope Grism Using Computer Generated Holograms

NASA Technical Reports Server (NTRS)

Dominguez, Margaret Z.; Content, David A.; Gong, Qian; Griesmann, Ulf; Hagopian, John G.; Marx, Catherine T; Whipple, Arthur L.

2017-01-01

Infrared Computer Generated Holograms (CGHs) were designed, manufactured and used to measure the performance of the grism (grating prism) prototype which includes testing Diffractive Optical Elements (DOE). The grism in the Wide Field Infrared Survey Telescope (WFIRST) will allow the surveying of a large section of the sky to find bright galaxies.

Near-field effect in the infrared range through periodic Germanium subwavelength arrays.

PubMed

Dong, Wei; Hirohata, Toru; Nakajima, Kazutoshi; Wang, Xiaoping

2013-11-04

Using finite-difference-time-domain simulation, we have studied the near-field effect of Germanium (Ge) subwavelength arrays designed in-plane with a normal incidence. Spectra of vertical electric field component normal to the surface show pronounced resonance peaks in an infrared range, which can be applied in a quantum well infrared photodetector. Unlike the near-field optics in metallic systems that are commonly related to surface plasmons, the intense vertical field along the surface of the Ge film can be interpreted as a combination of diffraction and waveguide theory. The existence of the enhanced field is confirmed by measuring the Fourier transform infrared spectra of fabricated samples. The positions of the resonant peaks obtained in experiment are in good agreement with our simulations.

MIRIS observation of near-infrared diffuse Galactic light

NASA Astrophysics Data System (ADS)

Onishi, Yosuke; Sano, Kei; Matsuura, Shuji; Jeong, Woong-Seob; Pyo, Jeonghyun; Kim, Il-Jong; Seo, Hyun Jong; Han, Wonyong; Lee, DaeHee; Moon, Bongkon; Park, Wonkee; Park, Younsik; Kim, MinGyu; Matsumoto, Toshio; Matsuhara, Hideo; Nakagawa, Takao; Tsumura, Kohji; Shirahata, Mai; Arai, Toshiaki; Ienaka, Nobuyuki

2018-06-01

We report near-infrared (IR) observations of high Galactic latitude clouds to investigate diffuse Galactic light (DGL), which is starlight scattered by interstellar dust grains. The observations were performed at 1.1 and 1.6 μm with a wide-field camera instrument, the Multi-purpose Infra-Red Imaging System (MIRIS) onboard the Korean satellite STSAT-3. The DGL brightness is measured by correlating the near-IR images with a far-IR 100 μm map of interstellar dust thermal emission. The wide-field observation of DGL provides the most accurate DGL measurement achieved to-date. We also find a linear correlation between optical and near-IR DGL in the MBM32 field. To study interstellar dust properties in MBM32, we adopt recent dust models with and without μm-sized very large grains and predict the DGL spectra, taking into account the reddening effect of the interstellar radiation field. The result shows that the observed color of the near-IR DGL is closer to the model spectra without very large grains. This may imply that dust growth in the observed MBM32 field is not active owing to the low density of its interstellar medium.

Wide-Field Infrared Survey Telescope (WFIRST) Interim Report

NASA Technical Reports Server (NTRS)

Green, J.; Schechter, P.; Baltay, C.; Bean, R.; Bennett, D.; Brown, R.; Conselice, C.; Donahue, M.; Gaudi, S.; Lauer, T.;

Deep CFHT Y-band Imaging of VVDS-F22 Field. II. Quasar Selection and Quasar Luminosity Function

NASA Astrophysics Data System (ADS)

Yang, Jinyi; Wu, Xue-Bing; Liu, Dezi; Fan, Xiaohui; Yang, Qian; Wang, Feige; McGreer, Ian D.; Fan, Zuhui; Yuan, Shuo; Shan, Huanyuan

2018-03-01

We report the results of a faint quasar survey in a one-square-degree field. The aim is to test the Y-K/g-z and J-K/i-Y color selection criteria for quasars at faint magnitudes to obtain a complete sample of quasars based on deep optical and near-infrared color–color selection and to measure the faint end of the quasar luminosity function (QLF) over a wide redshift range. We carried out a quasar survey based on the Y-K/g-z and J-K/i-Y quasar selection criteria, using the deep Y-band data obtained from our CFHT/WIRCam Y-band images in a two-degree field within the F22 field of the VIMOS VLT deep survey, optical co-added data from Sloan Digital Sky Survey Stripe 82 and deep near-infrared data from the UKIDSS Deep Extragalactic Survey in the same field. We discovered 25 new quasars at 0.5< z< 4.5 and i< 22.5 mag within one-square-degree field. The survey significantly increases the number of faint quasars in this field, especially at z∼ 2{--}3. It confirms that our color selections are highly complete in a wide redshift range (z< 4.5), especially over the quasar number density peak at z∼ 2{--}3, even for faint quasars. Combining all previous known quasars and new discoveries, we construct a sample with 109 quasars and measure the binned QLF and parametric QLF. Although the sample is small, our results agree with a pure luminosity evolution at lower redshift and luminosity evolution and density evolution model at redshift z> 2.5.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seo, H. J.; Lee, Hyung Mok; Lee, Myung Gyoon

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 connectsmore » 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.« less

Optical Design Trade Study for the Wide Field Infrared Survey Telescope [WFIRST

NASA Technical Reports Server (NTRS)

Content, David A.; Goullioud, R.; Lehan, John P.; Mentzell, John E.

2011-01-01

The Wide Field Infrared Survey Telescope (WFIRST) mission concept was ranked first in new space astrophysics mission by the Astro2010 Decadal Survey incorporating the Joint Dark Energy Mission (JDEM)-Omega payload concept and multiple science white papers. This mission is based on a space telescope at L2 studying exoplanets [via gravitational microlensing], probing dark energy, and surveying the near infrared sky. Since the release of NWNH, the WFIRST project has been working with the WFIRST science definition team (SDT) to refine mission and payload concepts. We present the driving requirements. The current interim reference mission point design, based on the use of a 1.3m unobscured aperture three mirror anastigmat form, with focal imaging and slitless spectroscopy science channels, is consistent with the requirements, requires no technology development, and out performs the JDEM-Omega design.

Optical field enhancement of nanometer-sized gaps at near-infrared frequencies.

PubMed

Ahn, Jae Sung; Kang, Taehee; Singh, Dilip K; Bahk, Young-Mi; Lee, Hyunhwa; Choi, Soo Bong; Kim, Dai-Sik

2015-02-23

We report near-field and far-field measurements of transmission through nanometer-sized gaps at near-infrared frequencies with varying the gap size from 1 nm to 10 nm. In the far-field measurements, we excluded direct transmission on the metal film surface via interferometric method. Kirchhoff integral formalism was used to relate the far-field intensity to the electric field at the nanogaps. In near-field measurements, field enhancement factors of the nanogaps were quantified by measuring transmission of the nanogaps using near-field scanning optical microscopy. All the measurements produce similar field enhancements of about ten, which we put in the context of comparing with the giant field enhancements in the terahertz regime.

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.

Preliminary Results from NEOWISE: An Enhancement to the Wide-field Infrared Survey Explorer for Solar System Science

NASA Astrophysics Data System (ADS)

Mainzer, A.; Bauer, J.; Grav, T.; Masiero, J.; Cutri, R. M.; Dailey, J.; Eisenhardt, P.; McMillan, R. S.; Wright, E.; Walker, R.; Jedicke, R.; Spahr, T.; Tholen, D.; Alles, R.; Beck, R.; Brandenburg, H.; Conrow, T.; Evans, T.; Fowler, J.; Jarrett, T.; Marsh, K.; Masci, F.; McCallon, H.; Wheelock, S.; Wittman, M.; Wyatt, P.; DeBaun, E.; Elliott, G.; Elsbury, D.; Gautier, T., IV; Gomillion, S.; Leisawitz, D.; Maleszewski, C.; Micheli, M.; Wilkins, A.

2011-04-01

The Wide-field Infrared Survey Explorer (WISE) has surveyed the entire sky at four infrared wavelengths with greatly improved sensitivity and spatial resolution compared to its predecessors, the Infrared Astronomical Satellite and the Cosmic Background Explorer. NASA's Planetary Science Division has funded an enhancement to the WISE data processing system called "NEOWISE" that allows detection and archiving of moving objects found in the WISE data. NEOWISE has mined the WISE images for a wide array of small bodies in our solar system, including near-Earth objects (NEOs), Main Belt asteroids, comets, Trojans, and Centaurs. By the end of survey operations in 2011 February, NEOWISE identified over 157,000 asteroids, including more than 500 NEOs and ~120 comets. The NEOWISE data set will enable a panoply of new scientific investigations.

First Light for Mimir, a Near-Infrared Wide-Field Imager, Spectrometer, and Polarimeter for the Perkins Telescope

NASA Astrophysics Data System (ADS)

Clemens, D. P.; Sarcia, D.; Tollestrup, E. V.; Grabau, A.; Bosh, A.; Buie, M.; Taylor, B.; Dunham, E.

2004-12-01

The Mimir instrument completed its 5-year development in our Boston University lab and was delivered this past July to Flagstaff, Arizona and the Perkins telescope for commissioning. Mimir is a "facility-class" multi-function near-infrared imager, spectrometer, and polarimeter developed under a joint program by Boston University and Lowell Observatory scientists, staff, and engineers. It fully covers the wavelength range 1-5 microns onto its 1024x1024 Aladdin III InSb array detector. In its wide-field imaging mode, a 10x10 arcmin field is sampled at 0.6 arcsec per pixel. In its narrow-field mode, the field is 3x3 arcmin, sampled at 0.2 arcsec per pixel. A full complement of JHKsL'M' broad-band filters are present in its four filter wheels. Spectroscopy is accomplished using a matched slit-plate and selector system, three grisms, and special spectroscopy filters (for order suppression). Polarimetry is accomplished using rotating half-wave plates and a fixed wire grid. All of these modes were certified in the lab; all have been certified at the Perkins telescope during the August/September commissioning run. Mode switches are accomplished in a matter of only seconds, making Mimir exceedingly versatile. The poster highlights the designs and components of Mimir as well as examples of images, spectra, and polarimetry from the commissioning telescope runs this past fall. Internal, shared-risk observations with Mimir begin this quarter. Mimir design and development has been funded by NASA, NSF, and the W.M. Keck Foundation.

Progress in the Field of Constructing Near-Infrared Light-Responsive Drug Delivery Platforms.

PubMed

Zhou, Fang; Wang, Hanjie; Chang, Jin

2016-03-01

Stimuli-responsive materials have taken replace of traditional drug carriers due to their ability to achieve controlled release of their encapsulated contents. A variety of sensitive materials, such as polymers that respond to pH, light, and magnetic fields, are widely used to construct drug carriers, and achieved good results. Specifically, near-infrared light (NIR) responsive materials are of particular interest in drug delivery, as NIR can penetrate body tissue and is minimally absorbed by the body's water and hemoglobin and is less harmful to healthy cells than UV or visible light. Thus, the near-infrared excitation drug delivery systems (NIRDDSs) have some essential advantages just like being efficient to kill tumor cells, accurate to achieve the tumor sites and less damage to human body. Also, in the process of building the carriers, we may achieve a combination of controlled release chemotherapy, photothermal therapy (PTT) or photodynamic therapy (PDT). In addition, besides utilizing as drug delivery platforms, some carriers can achieve multifunctional tumor diagnosis and treatment, such as magnetic resonance imaging, optical imaging, drug carriers and PTT. In this review, based on the mechanism of NIR, we highlight diverse near-infrared light-responsive drug delivery platforms and recent advances in the development of NIRDDSs for cancer therapy primarily.

NEAR-INFRARED CIRCULAR AND LINEAR POLARIMETRY OF MONOCEROS R2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Jungmi; Tamura, Motohide; Hough, James H.

We have conducted simultaneous JHK{sub 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 asmore » much as approximately 10% in the K{sub 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.« less

Bi-color near infrared thermoreflectometry: a method for true temperature field measurement.

PubMed

Sentenac, Thierry; Gilblas, Rémi; Hernandez, Daniel; Le Maoult, Yannick

2012-12-01

In a context of radiative temperature field measurement, this paper deals with an innovative method, called bicolor near infrared thermoreflectometry, for the measurement of true temperature fields without prior knowledge of the emissivity field of an opaque material. This method is achieved by a simultaneous measurement, in the near infrared spectral band, of the radiance temperature fields and of the emissivity fields measured indirectly by reflectometry. The theoretical framework of the method is introduced and the principle of the measurements at two wavelengths is detailed. The crucial features of the indirect measurement of emissivity are the measurement of bidirectional reflectivities in a single direction and the introduction of an unknown variable, called the "diffusion factor." Radiance temperature and bidirectional reflectivities are then merged into a bichromatic system based on Kirchhoff's laws. The assumption of the system, based on the invariance of the diffusion factor for two near wavelengths, and the value of the chosen wavelengths, are then discussed in relation to a database of several material properties. A thermoreflectometer prototype was developed, dimensioned, and evaluated. Experiments were carried out to outline its trueness in challenging cases. First, experiments were performed on a metallic sample with a high emissivity value. The bidirectional reflectivity was then measured from low signals. The results on erbium oxide demonstrate the power of the method with materials with high emissivity variations in near infrared spectral band.

Experimental study of near-field light collection efficiency of aperture fiber probe at near-infrared wavelengths.

PubMed

Tsumori, Nobuhiro; Takahashi, Motoki; Sakuma, Yoshiki; Saiki, Toshiharu

2011-10-10

We examined the near-field collection efficiency of near-infrared radiation for an aperture probe. We used InAs quantum dots as ideal point light sources with emission wavelengths ranging from 1.1 to 1.6 μm. We experimentally investigated the wavelength dependence of the collection efficiency and compared the results with computational simulations that modeled the actual probe structure. The observed degradation in the collection efficiency is attributed to the cutoff characteristics of the gold-clad tapered waveguide, which approaches an ideal conductor at near-infrared wavelengths. © 2011 Optical Society of America

Preliminary optical design of PANIC, a wide-field infrared camera for CAHA

NASA Astrophysics Data System (ADS)

Cárdenas, M. C.; Rodríguez Gómez, J.; Lenzen, R.; Sánchez-Blanco, E.

2008-07-01

In this paper, we present the preliminary optical design of PANIC (PAnoramic Near Infrared camera for Calar Alto), a wide-field infrared imager for the Calar Alto 2.2 m telescope. The camera optical design is a folded single optical train that images the sky onto the focal plane with a plate scale of 0.45 arcsec per 18 μm pixel. A mosaic of four Hawaii 2RG of 2k x 2k made by Teledyne is used as detector and will give a field of view of 31.9 arcmin x 31.9 arcmin. This cryogenic instrument has been optimized for the Y, J, H and K bands. Special care has been taken in the selection of the standard IR materials used for the optics in order to maximize the instrument throughput and to include the z band. The main challenges of this design are: to produce a well defined internal pupil which allows reducing the thermal background by a cryogenic pupil stop; the correction of off-axis aberrations due to the large field available; the correction of chromatic aberration because of the wide spectral coverage; and the capability of introduction of narrow band filters (~1%) in the system minimizing the degradation in the filter passband without a collimated stage in the camera. We show the optomechanical error budget and compensation strategy that allows our as built design to met the performances from an optical point of view. Finally, we demonstrate the flexibility of the design showing the performances of PANIC at the CAHA 3.5m telescope.

Photometric redshifts for the CFHTLS T0004 deep and wide fields

NASA Astrophysics Data System (ADS)

Coupon, J.; Ilbert, O.; Kilbinger, M.; McCracken, H. J.; Mellier, Y.; Arnouts, S.; Bertin, E.; Hudelot, P.; Schultheis, M.; Le Fèvre, O.; Le Brun, V.; Guzzo, L.; Bardelli, S.; Zucca, E.; Bolzonella, M.; Garilli, B.; Zamorani, G.; Zanichelli, A.; Tresse, L.; Aussel, H.

2009-06-01

Aims: We compute photometric redshifts in the fourth public release of the Canada-France-Hawaii Telescope Legacy Survey. This unique multi-colour catalogue comprises u^*, g', r', i', z' photometry in four deep fields of 1 deg2 each and 35 deg2 distributed over three wide fields. Methods: We used a template-fitting method to compute photometric redshifts calibrated with a large catalogue of 16 983 high-quality spectroscopic redshifts from the VVDS-F02, VVDS-F22, DEEP2, and the zCOSMOS surveys. The method includes correction of systematic offsets, template adaptation, and the use of priors. We also separated stars from galaxies using both size and colour information. Results: Comparing with galaxy spectroscopic redshifts, we find a photometric redshift dispersion, σΔ z/(1+z_s), of 0.028-0.30 and an outlier rate, |Δ z| ≥ 0.15× (1+z_s), of 3-4% in the deep field at i'_AB < 24. In the wide fields, we find a dispersion of 0.037-0.039 and an outlier rate of 3-4% at i'_AB < 22.5. Beyond i'_AB = 22.5 in the wide fields the number of outliers rises from 5% to 10% at i'_AB < 23 and i'_AB < 24, respectively. For the wide sample the systematic redshift bias stays below 1% to i'_AB < 22.5, whereas we find no significant bias in the deep fields. We investigated the effect of tile-to-tile photometric variations and demonstrated that the accuracy of our photometric redshifts is reduced by at most 21%. Application of our star-galaxy classifier reduced the contamination by stars in our catalogues from 60% to 8% at i'_AB < 22.5 in our field with the highest stellar density while keeping a complete galaxy sample. Our CFHTLS T0004 photometric redshifts are distributed to the community. Our release includes 592891 (i'_AB < 22.5) and 244701 (i'_AB < 24) reliable galaxy photometric redshifts in the wide and deep fields, respectively. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is

A New Method for Wide-field Near-IR Imaging with the Hubble Space Telescope

NASA Astrophysics Data System (ADS)

Momcheva, Ivelina G.; van Dokkum, Pieter G.; van der Wel, Arjen; Brammer, Gabriel B.; MacKenty, John; Nelson, Erica J.; Leja, Joel; Muzzin, Adam; Franx, Marijn

2017-01-01

We present a new technique for wide and shallow observations using the near-infrared channel of Wide Field Camera 3 (WFC3) on the Hubble Space Telescope (HST). Wide-field near-IR surveys with HST are generally inefficient, as guide star acquisitions make it impractical to observe more than one pointing per orbit. This limitation can be circumvented by guiding with gyros alone, which is possible as long as the telescope has three functional gyros. The method presented here allows us to observe mosaics of eight independent WFC3-IR pointings in a single orbit by utilizing the fact that HST drifts by only a very small amount in the 25 s between non-destructive reads of unguided exposures. By shifting the reads and treating them as independent exposures the full resolution of WFC3 can be restored. We use this “drift and shift” (DASH) method in the Cycle 23 COSMOS-DASH program, which will obtain 456 WFC3 H 160 pointings in 57 orbits, covering an area of 0.6 degree in the COSMOS field down to H 160 = 25. When completed, the program will more than triple the area of extra-galactic survey fields covered by near-IR imaging at HST resolution. We demonstrate the viability of the method with the first four orbits (32 pointings) of this program. We show that the resolution of the WFC3 camera is preserved, and that structural parameters of galaxies are consistent with those measured in guided observations.

Detecting the highest redshift (z > 8) quasi-stellar objects in a wide, near-infrared slitless spectroscopic survey

NASA Astrophysics Data System (ADS)

Roche, Nathan; Franzetti, Paolo; Garilli, Bianca; Zamorani, Giovanni; Cimatti, Andrea; Rossetti, Emanuel

2012-02-01

We investigate the prospects of extending observations of high-redshift quasi-stellar objects (QSOs) from the current z˜ 7 to z > 8 by means of a very wide-area near-infrared slitless spectroscopic survey, considering as an example the planned survey with the European Space Agency's Euclid telescope (scheduled for a 2019 launch). For any QSOs at z > 8.06, the strong Lyman α line will enter the wavelength range of the Euclid Near-Infrared Spectometer and Imaging Photometer (NISP). We perform a detailed simulation of near infrared spectrometer and imaging photometer (Euclid) NISP slitless spectroscopy (with the parameters of the wide survey) in an artificial field containing QSO spectra at all redshifts up to z= 12 and to a faint limit H= 22.5. QSO spectra are represented with a template based on a Sloan Digital Sky Survey composite spectrum, with the added effects of absorption from neutral hydrogen in the intergalactic medium. The spectra extracted from the simulation are analysed with an automated redshift finder, and a detection rate estimated as a function of H magnitude and redshift (defined as the proportion of spectra with both correct redshift measurements and classifications). We show that, as expected, spectroscopic identification of QSOs would reach deeper limits for the redshift ranges where either ? (0.67 < z < 2.05) or Lyman α (z > 8.06) is visible. Furthermore, if photometrically selected z > 8 spectra can be re-examined and refitted to minimize the effects of spectral contamination, the QSO detection rate in the Lyman α window will be increased by an estimated ˜60 per cent and will then be better here than at any other redshift, with an effective limit H≃ 21.5. With an extrapolated rate of QSO evolution, we predict that the Euclid wide (15 000 ?) spectroscopic survey will identify and measure spectroscopic redshifts for a total of 20-35 QSOs at z > 8.06 (reduced slightly to 19-33 if we apply a small correction for missed weak-lined QSOs

Near-Infrared Surveys and the Potential of an Upgraded WFCAM on UKIRT

NASA Astrophysics Data System (ADS)

Green, Richard F.; Kerr, Tom; Varricatt, Watson; Bold, Matthew; Kendrick, Rick; Hodapp, Klaus

2015-08-01

Near-infrared surveys provide the samples of faint objects essential for characterizing the assembly and evolution of galaxies, both at earliest cosmic times and near the peak of star formation and black hole activity. Near-IR broad and medium-band filter measurements are critical for accurate photometric redshifts and spectral energy distributions. The same areal coverage combined with time domain sampling reveals the variability properties of pre-main sequence stars in regions of active star formation, particularly in the presence of appreciable reddening. The possibility of deep, very wide-area K-band coverage creates the opportunity to trace the outer regions of the Galaxy and the Local Group. Targeting for James Webb Space Telescope will depend on accurate contemporaneous Near-IR astrometry. NASA's mission objectives for protecting working spacecraft from orbital debris are facilitated by near-IR characterization of debris, particularly for objects dark in the visible like solar panels.As one realization of advanced survey capability, we describe a proposed upgrade to the Wide-Field camera on the UKIRT 3.8-m. The powerful performance of an array of Teledyne Hawaii-4RG detectors combined with a new corrector and filters promise a Northern Hemisphere capability matched to the next generation of science requirements. Anticipated improvements include (nearly) contiguous detectors (alleviating the need for a large-step dither pattern), higher DQE, and no restriction on field because of guide stars. We would be assured of better wide-area astrometry and sensitivity compared to the generation of devices used for UKIDSS and HEMISPHERE.

Prime Focus Spectrograph: A very wide-field, massively multiplexed, optical & near-infrared spectrograph for Subaru Telescope

NASA Astrophysics Data System (ADS)

Tamura, Naoyuki

This short article is about Prime Focus Spectrograph (PFS), a very wide-field, massively-multiplexed, and optical & near-infrared (NIR) spectrograph as a next generation facility instrument on Subaru Telescope. More details and updates are available on the PFS official website (http://pfs.ipmu.jp), blog (http://pfs.ipmu.jp/blog/), and references therein. The project, instrument, & timeline PFS will position 2400 fibers to science targets or blank sky in the 1.3 degree field on the Subaru prime focus. These fibers will be quickly (~60sec) reconfigurable and feed the photons during exposures to the Spectrograph System (SpS). SpS consists of 4 modules each of which accommodate ~600 fibers and deliver spectral images ranging from 380nm to 1260nm simultaneously at one exposure via the 3 arms of blue, red, and NIR cameras. The instrument development has been undertaken by the international collaboration at the initiative of Kavli IPMU. The project is now going into the construction phase aiming at system integration and on-sky engineering observations in 2017-2018, and science operation in 2019. The survey design has also been under development envisioning a survey spanning ~300 nights over ~5 years in the framework of Subaru Strategic Program (SSP). The key science areas are: Cosmology, galaxy/AGN evolution, and Galactic Archaeology (GA) (Takada et al. 2014). The cosmology program will be to constrain the nature of dark energy via a survey of emission line galaxies over a comoving volume of 10 Gpc3 at z=0.8-2.4. In the galaxy/AGN program, the wide wavelength coverage of PFS as well as the large field of view will be exploited to characterize the galaxy populations and its clustering properties over a wide redshift range. A survey of color-selected galaxies/AGN at z = 1-2 will be conducted over 20 square degrees yielding a fair sample of galaxies with stellar masses down to ~1010 M ⊙. In the GA program, radial velocities and chemical abundances of stars in the Milky

Broadband near-field infrared spectromicroscopy using photothermal probes and synchrotron radiation.

PubMed

Donaldson, Paul M; Kelley, Chris S; Frogley, Mark D; Filik, Jacob; Wehbe, Katia; Cinque, Gianfelice

2016-02-08

In this paper, we experimentally demonstrate the use of infrared synchrotron radiation (IR-SR) as a broadband source for photothermal near-field infrared spectroscopy. We assess two methods of signal transduction; cantilever resonant thermal expansion and scanning thermal microscopy. By means of rapid mechanical chopping (50-150 kHz), we modulate the IR-SR at rates matching the contact resonance frequencies of atomic force microscope (AFM) cantilevers, allowing us to record interferograms yielding Fourier transform infrared (FT-IR) photothermal absorption spectra of polystyrene and cyanoacrylate films. Complementary offline measurements using a mechanically chopped CW IR laser confirmed that the resonant thermal expansion IR-SR measurements were below the diffraction limit, with a spatial resolution better than 500 nm achieved at a wavelength of 6 μm, i.e. λ/12 for the samples studied. Despite achieving the highest signal to noise so far for a scanning thermal microscopy measurement under conditions approaching near-field (dictated by thermal diffusion), the IR-SR resonant photothermal expansion FT-IR spectra measured were significantly higher in signal to noise in comparison with the scanning thermal data.

A wide deep infrared look at the Pleiades with UKIDSS: new constraints on the substellar binary fraction and the low-mass initial mass function

NASA Astrophysics Data System (ADS)

Lodieu, N.; Dobbie, P. D.; Deacon, N. R.; Hodgkin, S. T.; Hambly, N. C.; Jameson, R. F.

2007-09-01

We present the results of a deep wide-field near-infrared survey of 12 deg2 of the Pleiades conducted as part of the United Kingdom Infrared Telescope (UKIRT) Infrared Deep Sky Survey (UKIDSS) Galactic Cluster Survey (GCS). We have extracted over 340 high-probability proper motion (PM) members down to 0.03 Msolar using a combination of UKIDSS photometry and PM measurements obtained by cross-correlating the GCS with data from the Two Micron All Sky Survey, the Isaac Newton Telescope and the Canada-France-Hawaii Telescope. Additionally, we have unearthed 73 new candidate brown dwarf (BD) members on the basis of five-band UKIDSS photometry alone. We have identified 23 substellar multiple system candidates out of 63 candidate BDs from the (Y - K, Y) and (J - K, J) colour-magnitude diagrams, yielding a binary frequency of 28-44 per cent in the 0.075-0.030 Msolar mass range. Our estimate is three times larger than the binary fractions reported from high-resolution imaging surveys of field ultracool dwarfs and Pleiades BDs. However, it is marginally consistent with our earlier `peculiar' photometric binary fraction of 50 +/- 10 per cent presented by Pinfield et al., in good agreement with the 32-45 per cent binary fraction derived from the recent Monte Carlo simulations of Maxted & Jeffries and compatible with the 26 +/- 10 per cent frequency recently estimated by Basri & Reiners. A tentative estimate of the mass ratios from photometry alone seems to support the hypothesis that binary BDs tend to reside in near equal-mass ratio systems. In addition, the recovery of four Pleiades members targeted by high-resolution imaging surveys for multiplicity studies suggests that half of the binary candidates may have separations below the resolution limit of the Hubble Space Telescope or current adaptive optics facilities at the distance of the Pleiades (a ~7 au). Finally, we have derived luminosity and mass functions from the sample of photometric candidates with membership

Phase controlled homodyne infrared near-field microscopy and spectroscopy reveal inhomogeneity within and among individual boron nitride nanotubes.

PubMed

Xu, Xiaoji G; Tanur, Adrienne E; Walker, Gilbert C

2013-04-25

We propose a practical method to obtain near-field infrared absorption spectra in apertureless near-field scanning optical microscopy (aNSOM) through homodyne detection with a specific choice of reference phase. The underlying mechanism of the method is illustrated by theoretical and numeric models to show its ability to obtain absorptive rather than dispersive profiles in near-field infrared vibrational microscopy. The proposed near-field nanospectroscopic method is applied to obtain infrared spectra from regions of individual multiwall boron nitride nanotubes (BNNTs) in spatial regions smaller than the diffraction limit of the light source. The spectra suggest variations in interwall spacing within the individual tubes probed.

Experimental verification of the spectral shift between near- and far-field peak intensities of plasmonic infrared nanoantennas.

PubMed

Alonso-González, P; Albella, P; Neubrech, F; Huck, C; Chen, J; Golmar, F; Casanova, F; Hueso, L E; Pucci, A; Aizpurua, J; Hillenbrand, R

2013-05-17

Theory predicts a distinct spectral shift between the near- and far-field optical response of plasmonic antennas. Here we combine near-field optical microscopy and far-field spectroscopy of individual infrared-resonant nanoantennas to verify experimentally this spectral shift. Numerical calculations corroborate our experimental results. We furthermore discuss the implications of this effect in surface-enhanced infrared spectroscopy.

Near- and far-field spectroscopic imaging investigation of resonant square-loop infrared metasurfaces.

PubMed

D' Archangel, Jeffrey; Tucker, Eric; Kinzel, Ed; Muller, Eric A; Bechtel, Hans A; Martin, Michael C; Raschke, Markus B; Boreman, Glenn

2013-07-15

Optical metamaterials have unique properties which result from geometric confinement of the optical conductivity. We developed a series of infrared metasurfaces based on an array of metallic square loop antennas. The far-field absorption spectrum can be designed with resonances across the infrared by scaling the geometric dimensions. We measure the amplitude and phase of the resonant mode as standing wave patterns within the square loops using scattering-scanning near-field optical microscopy (s-SNOM). Further, using a broad-band synchrotron-based FTIR microscope and s-SNOM at the Advanced Light Source, we are able to correlate far-field spectra to near-field modes of the metasurface as the resonance is tuned between samples. The results highlight the importance of multi-modal imaging for the design and characterization of optical metamaterials.

Generalized theoretical method for the interaction between arbitrary nonuniform electric field and molecular vibrations: Toward near-field infrared spectroscopy and microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Iwasa, Takeshi, E-mail: tiwasa@mail.sci.hokudai.ac.jp; Takenaka, Masato; Taketsugu, Tetsuya

A theoretical method to compute infrared absorption spectra when a molecule is interacting with an arbitrary nonuniform electric field such as near-fields is developed and numerically applied to simple model systems. The method is based on the multipolar Hamiltonian where the light-matter interaction is described by a spatial integral of the inner product of the molecular polarization and applied electric field. The computation scheme is developed under the harmonic approximation for the molecular vibrations and the framework of modern electronic structure calculations such as the density functional theory. Infrared reflection absorption and near-field infrared absorption are considered as model systems.more » The obtained IR spectra successfully reflect the spatial structure of the applied electric field and corresponding vibrational modes, demonstrating applicability of the present method to analyze modern nanovibrational spectroscopy using near-fields. The present method can use arbitral electric fields and thus can integrate two fields such as computational chemistry and electromagnetics.« less

Generalized theoretical method for the interaction between arbitrary nonuniform electric field and molecular vibrations: Toward near-field infrared spectroscopy and microscopy.

PubMed

Iwasa, Takeshi; Takenaka, Masato; Taketsugu, Tetsuya

2016-03-28

A theoretical method to compute infrared absorption spectra when a molecule is interacting with an arbitrary nonuniform electric field such as near-fields is developed and numerically applied to simple model systems. The method is based on the multipolar Hamiltonian where the light-matter interaction is described by a spatial integral of the inner product of the molecular polarization and applied electric field. The computation scheme is developed under the harmonic approximation for the molecular vibrations and the framework of modern electronic structure calculations such as the density functional theory. Infrared reflection absorption and near-field infrared absorption are considered as model systems. The obtained IR spectra successfully reflect the spatial structure of the applied electric field and corresponding vibrational modes, demonstrating applicability of the present method to analyze modern nanovibrational spectroscopy using near-fields. The present method can use arbitral electric fields and thus can integrate two fields such as computational chemistry and electromagnetics.

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

PubMed Central

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

2015-01-01

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. PMID:25798327

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rybak, Leonid; Chuntonov, Lev; Gandman, Andrey

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.

Far-Field to Near-Field Coupling for Enhancing Light-Matter Interaction

NASA Astrophysics Data System (ADS)

Bonakdar, Alireza

This thesis reports on theoretical, modeling, and experimental research within the framework of a key scientific question, which is enhancing the coupling between diffraction-limited far-field and sub-wavelength quantum emitter/absorber. A typical optoelectronic device delivers an optical process such as light detection (e.g. photodetector) or light intensity modulation (e.g. electro-absorptive modulator). In conventional devices, optical process is in the form of far-field or guided wave modes. The main aim of this thesis is to show that converting these modes into near-field domain can enhance the performance of the optoelectronic device. Light in the form of far-field can be converted into near-field domain by the optical antenna. Among different optoelectronic devices, this thesis focuses mainly on integrating the optical antenna with infrared photodetectors. The available semiconductors have weak infrared absorption that reduces light detection efficiency. Integration of the optical antenna with infrared absorber (such as quantum wells in quantum well infrared photodetector (QWIP)) increases the infrared absorption. Particularly this integration is favorable as the optical antenna has low metallic loss in infrared region. The author of this thesis believes that optical antenna has unique properties in confining light on the scale of deep sub-wavelength, enhancing electric field intensity and delivering optical energy to semiconductor absorbers. These properties are reaching into practical applications only if overall optical performance is low loss, parameter free (independent of optical parameters such a polarization and angle of incident) and broadband. In this thesis, the integration of optical antenna with infrared photodetectors and thermophotovoltaic are researched and developed which satisfy the aforementioned criteria. In addition, several different optical antennas have been designed, fabricated and characterized in order to analyze and demonstrate

Low-frequency wide-field fluorescence lifetime imaging using a high-power near-infrared light-emitting diode light source

PubMed Central

Gioux, Sylvain; Lomnes, Stephen J.; Choi, Hak Soo; Frangioni, John V.

2010-01-01

Fluorescence lifetime imaging (FLi) could potentially improve exogenous near-infrared (NIR) fluorescence imaging, because it offers the capability of discriminating a signal of interest from background, provides real-time monitoring of a chemical environment, and permits the use of several different fluorescent dyes having the same emission wavelength. We present a high-power, LED-based, NIR light source for the clinical translation of wide-field (larger than 5 cm in diameter) FLi at frequencies up to 35 MHz. Lifetime imaging of indocyanine green (ICG), IRDye 800-CW, and 3,3′-diethylthiatricarbocyanine iodide (DTTCI) was performed over a large field of view (10 cm by 7.5 cm) using the LED light source. For comparison, a laser diode light source was employed as a gold standard. Experiments were performed both on the bench by diluting the fluorescent dyes in various chemical environments in Eppendorf tubes, and in vivo by injecting the fluorescent dyes mixed in Matrigel subcutaneously into CD-1 mice. Last, measured fluorescence lifetimes obtained using the LED and the laser diode sources were compared with those obtained using a state-of-the-art time-domain imaging system and with those previously described in the literature. On average, lifetime values obtained using the LED and the laser diode light sources were consistent, exhibiting a mean difference of 3% from the expected values and a coefficient of variation of 12%. Taken together, our study offers an alternative to laser diodes for clinical translation of FLi and explores the use of relatively low frequency modulation for in vivo imaging. PMID:20459250

Near-field spatial mapping of strongly interacting multiple plasmonic infrared antennas.

PubMed

Grefe, Sarah E; Leiva, Daan; Mastel, Stefan; Dhuey, Scott D; Cabrini, Stefano; Schuck, P James; Abate, Yohannes

2013-11-21

Near-field dipolar plasmon interactions of multiple infrared antenna structures in the strong coupling limit are studied using scattering-type scanning near-field optical microscope (s-SNOM) and theoretical finite-difference time-domain (FDTD) calculations. We monitor in real-space the evolution of plasmon dipolar mode of a stationary antenna structure as multiple resonantly matched dipolar plasmon particles are closely approaching it. Interparticle separation, length and polarization dependent studies show that the cross geometry structure favors strong interparticle charge-charge, dipole-dipole and charge-dipole Coulomb interactions in the nanometer scale gap region, which results in strong field enhancement in cross-bowties and further allows these structures to be used as polarization filters. The nanoscale local field amplitude and phase maps show that due to strong interparticle Coulomb coupling, cross-bowtie structures redistribute and highly enhance the out-of-plane (perpendicular to the plane of the sample) plasmon near-field component at the gap region relative to ordinary bowties.

HUBBLE SPACE TELESCOPE SPECTROSCOPY OF BROWN DWARFS DISCOVERED WITH THE WIDE-FIELD INFRARED SURVEY EXPLORER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schneider, Adam C.; Cushing, Michael C.; Kirkpatrick, J. Davy

2015-05-10

We present a sample of brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE) for which we have obtained Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) near-infrared grism spectroscopy. The sample (22 in total) was observed with the G141 grism covering 1.10–1.70 μm, while 15 were also observed with the G102 grism, which covers 0.90–1.10 μm. The additional wavelength coverage provided by the G102 grism allows us to (1) search for spectroscopic features predicted to emerge at low effective temperatures (e.g.,ammonia bands) and (2) construct a smooth spectral sequence across the T/Y boundary. We find no evidencemore » of absorption due to ammonia in the G102 spectra. Six of these brown dwarfs are new discoveries, three of which are found to have spectral types of T8 or T9. The remaining three, WISE J082507.35+280548.5 (Y0.5), WISE J120604.38+840110.6 (Y0), and WISE J235402.77+024015.0 (Y1), are the 19th, 20th, and 21st spectroscopically confirmed Y dwarfs to date. We also present HST grism spectroscopy and reevaluate the spectral types of five brown dwarfs for which spectral types have been determined previously using other instruments.« less

Developing Wide-Field Spatio-Spectral Interferometry for Far-Infrared Space Applications

NASA Technical Reports Server (NTRS)

Leisawitz, David; Bolcar, Matthew R.; Lyon, Richard G.; Maher, Stephen F.; Memarsadeghi, Nargess; Rinehart, Stephen A.; Sinukoff, Evan J.

2012-01-01

Interferometry is an affordable way to bring the benefits of high resolution to space far-IR astrophysics. We summarize an ongoing effort to develop and learn the practical limitations of an interferometric technique that will enable the acquisition of high-resolution far-IR integral field spectroscopic data with a single instrument in a future space-based interferometer. This technique was central to the Space Infrared Interferometric Telescope (SPIRIT) and Submillimeter Probe of the Evolution of Cosmic Structure (SPECS) space mission design concepts, and it will first be used on the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII). Our experimental approach combines data from a laboratory optical interferometer (the Wide-field Imaging Interferometry Testbed, WIIT), computational optical system modeling, and spatio-spectral synthesis algorithm development. We summarize recent experimental results and future plans.

Application of near-infrared spectroscopy to preservative-treated wood

Treesearch

Chi-Leung So; Stan T. Lebow; Thomas L. Eberhardt; Leslie H. Groom; Todd F. Shupe

2009-01-01

Near infrared (NIR) spectroscopy is now a widely-used technique in the field of forest products, especially for physical and mechanical property determinations. This technique is also ideal for the chemical analysis of wood. There has been a growing need to find a rapid, inexpensive and reliable method to distinguish between preservative-treated and untreated waste...

Quantitative Measurement of Local Infrared Absorption and Dielectric Function with Tip-Enhanced Near-Field Microscopy.

PubMed

Govyadinov, Alexander A; Amenabar, Iban; Huth, Florian; Carney, P Scott; Hillenbrand, Rainer

2013-05-02

Scattering-type scanning near-field optical microscopy (s-SNOM) and Fourier transform infrared nanospectroscopy (nano-FTIR) are emerging tools for nanoscale chemical material identification. Here, we push s-SNOM and nano-FTIR one important step further by enabling them to quantitatively measure local dielectric constants and infrared absorption. Our technique is based on an analytical model, which allows for a simple inversion of the near-field scattering problem. It yields the dielectric permittivity and absorption of samples with 2 orders of magnitude improved spatial resolution compared to far-field measurements and is applicable to a large class of samples including polymers and biological matter. We verify the capabilities by determining the local dielectric permittivity of a PMMA film from nano-FTIR measurements, which is in excellent agreement with far-field ellipsometric data. We further obtain local infrared absorption spectra with unprecedented accuracy in peak position and shape, which is the key to quantitative chemometrics on the nanometer scale.

Broadband near-field mid-infrared spectroscopy and application to phonon resonances in quartz.

PubMed

Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Ikemoto, Yuka; Okamura, Hidekazu

2012-05-07

Infrared (IR) spectroscopy is a versatile analytical method and nano-scale spatial resolution could be achieved by scattering type near-field optical microscopy (s-SNOM). The spectral bandwidth was, however, limited to approximately 300 cm(-1) with a laser light source. In the present study, the development of a broadband mid-IR near-field spectroscopy with a ceramic light source is demonstrated. A much wider bandwidth (at least 3000 to 1000 cm(-1)) is achieved with a ceramic light source. The experimental data on quartz Si-O phonon resonance bands are well reproduced by theoretical simulations indicating the validity of the present broadband near-field IR spectroscopy.

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.

Wide-Field InfraRed Survey Telescope WFIRST

NASA Technical Reports Server (NTRS)

Green, J.; Schechter, P.; Baltay, C.; Bean, R.; Bennett, D.; Brown, R.; Conselice, C.; Donahue, M.; Fan, X.; Rauscher, B.;

Mapping Free-Carriers in Multijunction Silicon Nanowires Using Infrared Near-Field Optical Microscopy.

PubMed

Ritchie, Earl T; Hill, David J; Mastin, Tucker M; Deguzman, Panfilo C; Cahoon, James F; Atkin, Joanna M

2017-11-08

We report the use of infrared (IR) scattering-type scanning near-field optical microscopy (s-SNOM) as a nondestructive method to map free-carriers in axially modulation-doped silicon nanowires (SiNWs) with nanoscale spatial resolution. Using this technique, we can detect local changes in the electrically active doping concentration based on the infrared free-carrier response in SiNWs grown using the vapor-liquid-solid (VLS) method. We demonstrate that IR s-SNOM is sensitive to both p-type and n-type free-carriers for carrier densities above ∼1 × 10 19 cm -3 . We also resolve subtle changes in local conductivity properties, which can be correlated with growth conditions and surface effects. The use of s-SNOM is especially valuable in low mobility materials such as boron-doped p-type SiNWs, where optimization of growth has been difficult to achieve due to the lack of information on dopant distribution and junction properties. s-SNOM can be widely employed for the nondestructive characterization of nanostructured material synthesis and local electronic properties without the need for contacts or inert atmosphere.

Validation of a high-power, time-resolved, near-infrared spectroscopy system for measurement of superficial and deep muscle deoxygenation during exercise.

PubMed

Koga, Shunsaku; Barstow, Thomas J; Okushima, Dai; Rossiter, Harry B; Kondo, Narihiko; Ohmae, Etsuko; Poole, David C

2015-06-01

Near-infrared assessment of skeletal muscle is restricted to superficial tissues due to power limitations of spectroscopic systems. We reasoned that understanding of muscle deoxygenation may be improved by simultaneously interrogating deeper tissues. To achieve this, we modified a high-power (∼8 mW), time-resolved, near-infrared spectroscopy system to increase depth penetration. Precision was first validated using a homogenous optical phantom over a range of inter-optode spacings (OS). Coefficients of variation from 10 measurements were minimal (0.5-1.9%) for absorption (μa), reduced scattering, simulated total hemoglobin, and simulated O2 saturation. Second, a dual-layer phantom was constructed to assess depth sensitivity, and the thickness of the superficial layer was varied. With a superficial layer thickness of 1, 2, 3, and 4 cm (μa = 0.149 cm(-1)), the proportional contribution of the deep layer (μa = 0.250 cm(-1)) to total μa was 80.1, 26.9, 3.7, and 0.0%, respectively (at 6-cm OS), validating penetration to ∼3 cm. Implementation of an additional superficial phantom to simulate adipose tissue further reduced depth sensitivity. Finally, superficial and deep muscle spectroscopy was performed in six participants during heavy-intensity cycle exercise. Compared with the superficial rectus femoris, peak deoxygenation of the deep rectus femoris (including the superficial intermedius in some) was not significantly different (deoxyhemoglobin and deoxymyoglobin concentration: 81.3 ± 20.8 vs. 78.3 ± 13.6 μM, P > 0.05), but deoxygenation kinetics were significantly slower (mean response time: 37 ± 10 vs. 65 ± 9 s, P ≤ 0.05). These data validate a high-power, time-resolved, near-infrared spectroscopy system with large OS for measuring the deoxygenation of deep tissues and reveal temporal and spatial disparities in muscle deoxygenation responses to exercise. Copyright © 2015 the American Physiological Society.

The Chandra Deep Wide-Field Survey: Completing the new generation of Chandra extragalactic surveys

NASA Astrophysics Data System (ADS)

Hickox, Ryan

2016-09-01

Chandra X-ray surveys have revolutionized our view of the growth of black holes across cosmic time. Recently, fundamental questions have emerged about the connection of AGN to their host large scale structures that clearly demand a wide, deep survey over a large area, comparable to the recent extensive Chandra surveys in smaller fields. We propose the Chandra Deep Wide-Field Survey (CDWFS) covering the central 6 sq. deg in the Bootes field, totaling 1.025 Ms (building on 550 ks from the HRC GTO program). CDWFS will efficiently probe a large cosmic volume, allowing us to carry out accurate new investigations of the connections between black holes and their large-scale structures, and will complete the next generation surveys that comprise a key part of Chandra's legacy.

Precision Pointing for the Wide-Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Stoneking, Eric; Hsu, Oscar; Welter, Gary

2017-01-01

The Wide-Field Infrared Survey Telescope (WFIRST) mission, scheduled for a mid-2020's launch, is currently in its definition phase. The mission is designed to investigate essential questions in the areas of dark energy, exoplanets, and infrared astrophysics. WFIRST will use a 2.4-meter primary telescope (same size as the Hubble Space Telescope's primary mirror) and two instruments: the Wide Field Instrument (WFI) and the Coronagraph Instrument (CGI). In order to ad-dress the critical science requirements, the WFIRST mission will conduct large-scale surveys of the infrared sky, requiring both agility and precision pointing (11.6 milli-arcsec stability, 14 milli-arcsec jitter). This paper describes some of the challenges this mission profile presents to the GNC subsystem, and some of the design elements chosen to accommodate those challenges. The high-galactic-latitude survey is characterized by 3-minute observations separated by slews ranging from 0.025 deg to 0.8 deg. The need for observation efficiency drives the slew and settle process to be as rapid as possible. A description of the shaped slew profile chosen to minimize excitation of structural oscillation, and the handoff from star tracker-gyro control to fine guidance sensor control is detailed. Also presented is the fine guidance sensor (FGS), which is integral with the primary instrument (WFI). The FGS is capable of tracking up to 18 guide stars, enabling robust FGS acquisition and precision pointing. To avoid excitation of observatory structural jitter, reaction wheel speeds are operationally maintained within set limits. In addition, the wheel balance law is designed to maintain 1-Hz separation between the wheel speeds to avoid reinforcing jitter excitation at any particular frequency. The wheel balance law and operational implications are described. Finally, the candidate GNC hardware suite needed to meet the requirements of the mission is presented.

Precision Pointing for the Wide-Field Infrared Survey Telescope(WFIRST)

NASA Technical Reports Server (NTRS)

Stoneking, Eric T.; Hsu, Oscar C.; Welter, Gary

2017-01-01

The Wide-Field Infrared Survey Telescope (WFIRST) mission, scheduled for a mid-2020's launch, is currently in its definition phase. The mission is designed to investigate essential questions in the areas of dark energy, exoplanets, and infrared astrophysics. WFIRST will use a 2.4-meter primary telescope (same size as the Hubble Space Telescope's primary mirror) and two instruments: the Wide Field Instrument (WFI) and the Coronagraph Instrument (CGI). In order to address the critical science requirements, the WFIRST mission will conduct large-scale surveys of the infrared sky, requiring both agility and precision pointing (11.6 milli-arcsec stability, 14 milli-arcsec jitter). This paper describes some of the challenges this mission profile presents to the Guidance, Navigation, and Control (GNC) subsystem, and some of the design elements chosen to accommodate those challenges. The high-galactic-latitude survey is characterized by 3-minute observations separated by slews ranging from 0.025 deg to 0.8 deg. The need for observation efficiency drives the slew and settle process to be as rapid as possible. A description of the shaped slew profile chosen to minimize excitation of structural oscillation, and the handoff from star tracker-gyro control to fine guidance sensor control is detailed. Also presented is the fine guidance sensor (FGS), which is integral with the primary instrument (WFI). The FGS is capable of tracking up to 18 guide stars, enabling robust FGS acquisition and precision pointing. To avoid excitation of observatory structural jitter, reaction wheel speeds are operationally maintained within set limits. In addition, the wheel balance law is designed to maintain 1-Hz separation between the wheel speeds to avoid reinforcing jitter excitation at any particular frequency. The wheel balance law and operational implications are described. Finally, the candidate GNC hardware suite needed to meet the requirements of the mission is presented.

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.

Morphology and Structure of Ultraluminous Infrared Galaxies at z ≈ 2 in the EGS Field

NASA Astrophysics Data System (ADS)

Fang, G. W.; Ma, Z. Y.; Chen, Y.; Kong, X.

2014-11-01

Using high-resolution HST WFC3 (Hubble Space Telescope Wide Field Camera 3) F160W imaging from the CANDELS-EGS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Extended Groth Strip) field, we present the morphology analysis of 9 ultraluminous infrared galaxies (ULIRGs) at z≈2. We find a wide range of morphological diversities for these ULIRGs, from spheroid to multiple bright nuclei or diffuse structures, e.g., double nuclei, bridges, dual asymmetries, irregular, or elliptical structures. In quantitative, these sources show a lower Gini coefficient (G) and a higher moment (M_{20}) in the rest-frame optical morphology, compared to the lower redshift counterparts, indicating less concentrated and symmetric spatial distribution of the stellar mass of ULIRGs at z≈2. Moreover, we derive accurate effective radii of these ULIRGs through 2-D profile fitting, which range from 2.4 to 5.8 kpc, with a mean value of (3.9±1.1) kpc. We find that the sizes of these ULIRGs at z≈2 are on average one to two times smaller than those of the local star-forming galaxies with analogous stellar mass. Our results are consistent with those studies at similar redshift and infrared luminosity.

TIFR Near Infrared Imaging Camera-II on the 3.6 m Devasthal Optical Telescope

NASA Astrophysics Data System (ADS)

Baug, T.; Ojha, D. K.; Ghosh, S. K.; Sharma, S.; Pandey, A. K.; Kumar, Brijesh; Ghosh, Arpan; Ninan, J. P.; Naik, M. B.; D’Costa, S. L. A.; Poojary, S. S.; Sandimani, P. R.; Shah, H.; Krishna Reddy, B.; Pandey, S. B.; Chand, H.

Tata Institute of Fundamental Research (TIFR) Near Infrared Imaging Camera-II (TIRCAM2) is a closed-cycle Helium cryo-cooled imaging camera equipped with a Raytheon 512×512 pixels InSb Aladdin III Quadrant focal plane array (FPA) having sensitivity to photons in the 1-5μm wavelength band. In this paper, we present the performance of the camera on the newly installed 3.6m Devasthal Optical Telescope (DOT) based on the calibration observations carried out during 2017 May 11-14 and 2017 October 7-31. After the preliminary characterization, the camera has been released to the Indian and Belgian astronomical community for science observations since 2017 May. The camera offers a field-of-view (FoV) of ˜86.5‧‧×86.5‧‧ on the DOT with a pixel scale of 0.169‧‧. The seeing at the telescope site in the near-infrared (NIR) bands is typically sub-arcsecond with the best seeing of ˜0.45‧‧ realized in the NIR K-band on 2017 October 16. The camera is found to be capable of deep observations in the J, H and K bands comparable to other 4m class telescopes available world-wide. Another highlight of this camera is the observational capability for sources up to Wide-field Infrared Survey Explorer (WISE) W1-band (3.4μm) magnitudes of 9.2 in the narrow L-band (nbL; λcen˜ 3.59μm). Hence, the camera could be a good complementary instrument to observe the bright nbL-band sources that are saturated in the Spitzer-Infrared Array Camera (IRAC) ([3.6] ≲ 7.92 mag) and the WISE W1-band ([3.4] ≲ 8.1 mag). Sources with strong polycyclic aromatic hydrocarbon (PAH) emission at 3.3μm are also detected. Details of the observations and estimated parameters are presented in this paper.

Wide Field Imaging of the Hubble Deep Field-South Region III: Catalog

NASA Technical Reports Server (NTRS)

Palunas, Povilas; Collins, Nicholas R.; Gardner, Jonathan P.; Hill, Robert S.; Malumuth, Eliot M.; Rhodes, Jason; Teplitz, Harry I.; Woodgate, Bruce E.

2002-01-01

We present 1/2 square degree uBVRI imaging around the Hubble Deep Field - South. These data have been used in earlier papers to examine the QSO population and the evolution of the correlation function in the region around the HDF-S. The images were obtained with the Big Throughput Camera at CTIO in September 1998. The images reach 5 sigma limits of u approx. 24.4, B approx. 25.6, V approx. 25.3, R approx. 24.9 and I approx. 23.9. We present a catalog of approx. 22,000 galaxies. We also present number-magnitude counts and a comparison with other observations of the same field. The data presented here are available over the world wide web.

Resolution enhancement of wide-field interferometric microscopy by coupled deep autoencoders.

PubMed

Işil, Çağatay; Yorulmaz, Mustafa; Solmaz, Berkan; Turhan, Adil Burak; Yurdakul, Celalettin; Ünlü, Selim; Ozbay, Ekmel; Koç, Aykut

2018-04-01

Wide-field interferometric microscopy is a highly sensitive, label-free, and low-cost biosensing imaging technique capable of visualizing individual biological nanoparticles such as viral pathogens and exosomes. However, further resolution enhancement is necessary to increase detection and classification accuracy of subdiffraction-limited nanoparticles. In this study, we propose a deep-learning approach, based on coupled deep autoencoders, to improve resolution of images of L-shaped nanostructures. During training, our method utilizes microscope image patches and their corresponding manual truth image patches in order to learn the transformation between them. Following training, the designed network reconstructs denoised and resolution-enhanced image patches for unseen input.

Modulated near-field spectral extraction of broadband mid-infrared signals with a ceramic light source.

PubMed

Ishikawa, Michio; Katsura, Makoto; Nakashima, Satoru; Aizawa, Kento; Inoue, Tsutomu; Okamura, Hidekazu; Ikemoto, Yuka

2011-06-20

In order to obtain broadband near-field infrared (IR) spectra, a Fourier-transform IR spectrometer (FT-IR) and a ceramic light source were used with a scattering-type scanning near-field optical microscope (s-SNOM). To suppress the background (far-field) scattering, the distance between the scattering probe and the sample was modulated with frequency Ω by a piezo-electric actuator, and the Ω component was extracted from the signal with a lock-in detection. With Ω=30 kHz, a peak-to-peak modulation amplitude of 198 nm, and a probe with smooth surface near the tip, broadband near-field IR spectra could be obtained in the 1200-2500 cm(-1).

The Multiwavelength Survey by Yale-Chile (MUSYC): Deep Near-Infrared Imaging and the Selection of Distant Galaxies

NASA Astrophysics Data System (ADS)

Quadri, Ryan; Marchesini, Danilo; van Dokkum, Pieter; Gawiser, Eric; Franx, Marijn; Lira, Paulina; Rudnick, Gregory; Urry, C. Megan; Maza, José; Kriek, Mariska; Barrientos, L. Felipe; Blanc, Guillermo A.; Castander, Francisco J.; Christlein, Daniel; Coppi, Paolo S.; Hall, Patrick B.; Herrera, David; Infante, Leopoldo; Taylor, Edward N.; Treister, Ezequiel; Willis, Jon P.

2007-09-01

We present deep near-infrared JHK imaging of four 10' × 10' fields. The observations were carried out as part of the Multiwavelength Survey by Yale-Chile (MUSYC) with ISPI on the CTIO 4 m telescope. The typical point-source limiting depths are J ~ 22.5, H ~ 21.5, and K ~ 21 (5 σ Vega). The effective seeing in the final images is ~1.0″. We combine these data with MUSYC UBVRIz imaging to create K-selected catalogs that are unique for their uniform size, depth, filter coverage, and image quality. We investigate the rest-frame optical colors and photometric redshifts of galaxies that are selected using common color selection techniques, including distant red galaxies (DRGs), star-forming and passive BzKs, and the rest-frame UV-selected BM, BX, and Lyman break galaxies (LBGs). These techniques are effective at isolating large samples of high-redshift galaxies, but none provide complete or uniform samples across the targeted redshift ranges. The DRG and BM/BX/LBG criteria identify populations of red and blue galaxies, respectively, as they were designed to do. The star-forming BzKs have a very wide redshift distribution, extending down to z ~ 1, a wide range of colors, and may include galaxies with very low specific star formation rates. In comparison, the passive BzKs are fewer in number, have a different distribution of K magnitudes, and have a somewhat different redshift distribution. By combining either the DRG and BM/BX/LBG criteria, or the star-forming and passive BzK criteria, it appears possible to define a reasonably complete sample of galaxies to our flux limit over specific redshift ranges. However, the redshift dependence of both the completeness and sampled range of rest-frame colors poses an ultimate limit to the usefulness of these techniques.

Near-UV Sources in the Hubble Ultra Deep Field: The Catalog

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.; Voyrer, Elysse; de Mello, Duilia F.; Siana, Brian; Quirk, Cori; Teplitz, Harry I.

2009-01-01

The catalog from the first high resolution U-band image of the Hubble Ultra Deep Field, taken with Hubble s Wide Field Planetary Camera 2 through the F300W filter, is presented. We detect 96 U-band objects and compare and combine this catalog with a Great Observatories Origins Deep Survey (GOODS) B-selected catalog that provides B, V, i, and z photometry, spectral types, and photometric redshifts. We have also obtained Far-Ultraviolet (FUV, 1614 Angstroms) data with Hubble s Advanced Camera for Surveys Solar Blind Channel (ACS/SBC) and with Galaxy Evolution Explorer (GALEX). We detected 31 sources with ACS/SBC, 28 with GALEX/FUV, and 45 with GALEX/NUV. The methods of observations, image processing, object identification, catalog preparation, and catalog matching are presented.

The High AV Quasar Survey: Reddened Quasi-Stellar Objects Selected from Optical/Near-Infrared Photometry—II

NASA Astrophysics Data System (ADS)

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

2015-03-01

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.

Brown carbon absorption in the red and near-infrared spectral region

NASA Astrophysics Data System (ADS)

Hoffer, András; Tóth, Ádám; Pósfai, Mihály; Eddy Chung, Chul; Gelencsér, András

2017-06-01

Black carbon (BC) aerosols have often been assumed to be the only light-absorbing carbonaceous particles in the red and near-infrared spectral regions of solar radiation in the atmosphere. Here we report that tar balls (a specific type of organic aerosol particles from biomass burning) do absorb red and near-infrared radiation significantly. Tar balls were produced in a laboratory experiment, and their chemical and optical properties were measured. The absorption of these particles in the range between 470 and 950 nm was measured with an aethalometer, which is widely used to measure atmospheric aerosol absorption. We find that the absorption coefficient of tar balls at 880 nm is more than 10 % of that at 470 nm. The considerable absorption of red and infrared light by tar balls also follows from their relatively low absorption Ångström coefficient (and significant mass absorption coefficient) in the spectral range between 470 and 950 nm. Our results support the previous finding that tar balls may play an important role in global warming. Due to the non-negligible absorption of tar balls in the near-infrared region, the absorption measured in the field at near-infrared wavelengths cannot solely be due to soot particles.

Near field ice detection using infrared based optical imaging technology

NASA Astrophysics Data System (ADS)

Abdel-Moati, Hazem; Morris, Jonathan; Zeng, Yousheng; Corie, Martin Wesley; Yanni, Victor Garas

2018-02-01

If not detected and characterized, icebergs can potentially pose a hazard to oil and gas exploration, development and production operations in arctic environments as well as commercial shipping channels. In general, very large bergs are tracked and predicted using models or satellite imagery. Small and medium bergs are detectable using conventional marine radar. As icebergs decay they shed bergy bits and growlers, which are much smaller and more difficult to detect. Their low profile above the water surface, in addition to occasional relatively high seas, makes them invisible to conventional marine radar. Visual inspection is the most common method used to detect bergy bits and growlers, but the effectiveness of visual inspections is reduced by operator fatigue and low light conditions. The potential hazard from bergy bits and growlers is further increased by short detection range (<1 km). As such, there is a need for robust and autonomous near-field detection of such smaller icebergs. This paper presents a review of iceberg detection technology and explores applications for infrared imagers in the field. Preliminary experiments are performed and recommendations are made for future work, including a proposed imager design which would be suited for near field ice detection.

Phase resolved near-field imaging of propagating waves in infrared tapered slot antennas

NASA Astrophysics Data System (ADS)

Florence, Louis A.; Kinzel, Edward C.; Olmon, Robert L.; Ginn, James C.; Raschke, Markus B.; Boreman, Glenn D.

2012-11-01

Tapered slot antennas (TSAs) consist of a planar non-resonant structure which couples incident radiation to a propagating waveguide mode. They are commonly used at microwave and radio frequencies because they are fundamentally broadband and have small profiles. Because of their planar layout and broadband response they have recently been scaled to infrared frequencies where they have advantages for sensing and energy harvesting. We use scattering-type scanning near-field optical microscopy (s-SNOM) to study the mode transformation of two types of TSA operating in the thermal infrared (λ0 = 10.6 μm) with respect to electric field amplitude and phase. The results agree well with simulation showing both the phase reversal across the tapered slot and the traveling of wave fronts along the tapered slot, yet they also reveal high sensitivity of device performance to inhomogeneities in the geometry or illumination. This study will aid future design and analysis of practical non-resonant antennas operating at optical and infrared frequencies.

All-photonic drying and sintering process via flash white light combined with deep-UV and near-infrared irradiation for highly conductive copper nano-ink

PubMed Central

Hwang, Hyun-Jun; Oh, Kyung-Hwan; Kim, Hak-Sung

2016-01-01

We developed an ultra-high speed photonic sintering method involving flash white light (FWL) combined with near infrared (NIR) and deep UV light irradiation to produce highly conductive copper nano-ink film. Flash white light irradiation energy and the power of NIR/deep UV were optimized to obtain high conductivity Cu films. Several microscopic and spectroscopic characterization techniques such as scanning electron microscopy (SEM), a x-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy were employed to characterize the Cu nano-films. Optimally sintered Cu nano-ink films produced using a deep UV-assisted flash white light sintering technique had the lowest resistivity (7.62 μΩ·cm), which was only 4.5-fold higher than that of bulk Cu film (1.68 μΩ•cm). PMID:26806215

All-photonic drying and sintering process via flash white light combined with deep-UV and near-infrared irradiation for highly conductive copper nano-ink.

PubMed

Hwang, Hyun-Jun; Oh, Kyung-Hwan; Kim, Hak-Sung

2016-01-25

We developed an ultra-high speed photonic sintering method involving flash white light (FWL) combined with near infrared (NIR) and deep UV light irradiation to produce highly conductive copper nano-ink film. Flash white light irradiation energy and the power of NIR/deep UV were optimized to obtain high conductivity Cu films. Several microscopic and spectroscopic characterization techniques such as scanning electron microscopy (SEM), a x-ray diffraction (XRD), and Fourier-transform infrared (FT-IR) spectroscopy were employed to characterize the Cu nano-films. Optimally sintered Cu nano-ink films produced using a deep UV-assisted flash white light sintering technique had the lowest resistivity (7.62 μΩ·cm), which was only 4.5-fold higher than that of bulk Cu film (1.68 μΩ•cm).

Recovery of permittivity and depth from near-field data as a step toward infrared nanotomography.

PubMed

Govyadinov, Alexander A; Mastel, Stefan; Golmar, Federico; Chuvilin, Andrey; Carney, P Scott; Hillenbrand, Rainer

2014-07-22

The increasing complexity of composite materials structured on the nanometer scale requires highly sensitive analytical tools for nanoscale chemical identification, ideally in three dimensions. While infrared near-field microscopy provides high chemical sensitivity and nanoscopic spatial resolution in two dimensions, the quantitative extraction of material properties of three-dimensionally structured samples has not been achieved yet. Here we introduce a method to perform rapid recovery of the thickness and permittivity of simple 3D structures (such as thin films and nanostructures) from near-field measurements, and provide its first experimental demonstration. This is accomplished via a novel nonlinear invertible model of the imaging process, taking advantage of the near-field data recorded at multiple harmonics of the oscillation frequency of the near-field probe. Our work enables quantitative nanoscale-resolved optical studies of thin films, coatings, and functionalization layers, as well as the structural analysis of multiphase materials, among others. It represents a major step toward the further goal of near-field nanotomography.

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;

Wide Field Infra-Red Survey Telescope (WFIRST) 2.4-Meter Mission Study

NASA Technical Reports Server (NTRS)

Content, D.; Aaron, K.; Alplanalp, L.; Anderson, K.; Capps, R.; Chang, Z.; Dooley, J.; Egerman, R.; Goullioud, R.; Klein, D.;

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.

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

PubMed

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 μm(2) 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.

Novel concepts in near-field optics: from magnetic near-field to optical forces

NASA Astrophysics Data System (ADS)

Yang, Honghua

Driven by the progress in nanotechnology, imaging and spectroscopy tools with nanometer spatial resolution are needed for in situ material characterizations. Near-field optics provides a unique way to selectively excite and detect elementary electronic and vibrational interactions at the nanometer scale, through interactions of light with matter in the near-field region. This dissertation discusses the development and applications of near-field optical imaging techniques, including plasmonic material characterization, optical spectral nano-imaging and magnetic field detection using scattering-type scanning near-field optical microscopy (s-SNOM), and exploring new modalities of optical spectroscopy based on optical gradient force detection. Firstly, the optical dielectric functions of one of the most common plasmonic materials---silver is measured with ellipsometry, and analyzed with the Drude model over a broad spectral range from visible to mid-infrared. This work was motivated by the conflicting results of previous measurements, and the need for accurate values for a wide range of applications of silver in plasmonics, optical antennas, and metamaterials. This measurement provides a reference for dielectric functions of silver used in metamaterials, plasmonics, and nanophotonics. Secondly, I implemented an infrared s-SNOM instrument for spectroscopic nano-imaging at both room temperature and low temperature. As one of the first cryogenic s-SNOM instruments, the novel design concept and key specifications are discussed. Initial low-temperature and high-temperature performances of the instrument are examined by imaging of optical conductivity of vanadium oxides (VO2 and V2O 3) across their phase transitions. The spectroscopic imaging capability is demonstrated on chemical vibrational resonances of Poly(methyl methacrylate) (PMMA) and other samples. The third part of this dissertation explores imaging of optical magnetic fields. As a proof-of-principle, the magnetic

Near infrared spectrum simulation applied to human skin for diagnosis

NASA Astrophysics Data System (ADS)

Tsai, Chen-Mu; Fang, Yi-Chin; Wang, Chih-Yu; Chiu, Pin-Chun; Wu, Guo-Ying; Zheng, Wei-Chi; Chemg, Shih-Hao

2007-11-01

This research proposes a new method for skin diagnose using near infrared as the light source (750nm~1300nm). Compared to UV and visible light, near infrared might penetrate relatively deep into biological soft tissue in some cases although NIR absorption property of tissue is not a constant for water, fat, and collagen etc. In the research, NIR absorption and scattering properties for skin are discussed firstly using the theory of molecule vibration from Quantum physics and Solid State Physics; secondly the practical model for various NIR absorption spectrum to skin tissue are done by optical simulation for human skin. Finally, experiments are done for further identification of proposed model for human skin and its reaction to near infrared. Results show success with identification from both theory and experiments.

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.

Near-Field Infrared Pump-Probe Imaging of Surface Phonon Coupling in Boron Nitride Nanotubes.

PubMed

Gilburd, Leonid; Xu, Xiaoji G; Bando, Yoshio; Golberg, Dmitri; Walker, Gilbert C

2016-01-21

Surface phonon modes are lattice vibrational modes of a solid surface. Two common surface modes, called longitudinal and transverse optical modes, exhibit lattice vibration along or perpendicular to the direction of the wave. We report a two-color, infrared pump-infrared probe technique based on scattering type near-field optical microscopy (s-SNOM) to spatially resolve coupling between surface phonon modes. Spatially varying couplings between the longitudinal optical and surface phonon polariton modes of boron nitride nanotubes are observed, and a simple model is proposed.

Achieving deep-red-to-near-infrared emissions in Sn-doped Cu-In-S/ZnS quantum dots for red-enhanced white LEDs and near-infrared LEDs.

PubMed

Chen, Jixin; Li, Ye; Wang, Le; Zhou, Tianliang; Xie, Rong-Jun

2018-05-16

Semiconductor quantum dots (QDs) are promising luminescent materials for use in lighting, display and bio-imaging, and the color tuning is a necessity for such applications. In this work, we report tunable colors and deep-red or near infrared (NIR) emissions in Cu-In-S and Cu-In-S/ZnS QDs by incorporating Sn. These QDs (with a size of 5 nm) with varying Sn concentrations and/or Cu/In ratios were synthesized by a non-injection method, and characterized by a variety of analytical techniques (i.e., XRD, TEM, XPS, absorption, photoluminescence, decay time, etc.). The Cu-Sn-In-S and Cu-Sn-In-S/ZnS QDs with Cu/In = 1/2 show the emission maximum in the ranges of 701-894 nm and 628-785 nm, respectively. The red-shift in emission is ascribed to the decrease of the band gap with the Sn doping. The highest quantum yield of 75% is achieved in Cu-Sn-In-S/ZnS with 0.1 mmol Sn and Cu/In = 1/2. Both the white and NIR LEDs were fabricated by using Cu-Sn-In-S/ZnS QDs and a 365 nm LED chip. The white LED exhibits superhigh color rendering indices of Ra = 97.2 and R9 = 91 and a warm color temperature of 2700 K. And the NIR LED shows an interesting broadband near-infrared emission centered at 741 nm, allowing for applications in optical communication, sensing and medical devices.

Optical And Near-infrared Variability Among Distant Galactic Nuclei Of The CANDELS EGS Field

NASA Astrophysics Data System (ADS)

Grogin, Norman A.; Dahlen, T.; Donley, J.; Koekemoer, A. M.; Salvato, M.; CANDELS Collaboration

2014-01-01

The CANDELS HST Multi-cycle Treasury Program completed its observations of the EGS field in May 2013. The coverage comprises WFC3/IR exposures in J-band and H-band across a contiguous 200 square arcminutes, and coordinated parallel ACS/WFC exposures in V-band and I-band across a contiguous 270 square arcminutes that largely overlaps the WFC3/IR coverage. These observations were split between two epochs with 52-day spacing for the primary purpose of high-redshift supernovae (SNe) detection and follow-up. However, this 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 in combination with the original EGS ACS imaging from 2004, to time-scales of up 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 preliminary results of our EGS variability analysis, including a comparison of the HST ONIVs with the known AGN candidates in the field 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. We compare these results with our prior variability analysis of the similarly-observed CANDELS UDS field from 2011 and CANDELS COSMOS field from 2012.

Titan's Thermal Emission: Analysis Of Near-surface Temperatures Via Mid-infrared Measurements

NASA Astrophysics Data System (ADS)

Sadino, Jeff; Parrish, P. D.; Orton, G. S.; Burl, M. C.; Davies, A. G.; Irwin, P. G.; Teanby, N. A.; Flasar, F. M.; Cassini/CIRS investigation Team

2006-09-01

After Courtin and Kim 2002, tropospheric and near-surface temperatures of Titan may be obtained by examining mid-infrared radiances at 300 and 500 wavenumbers (33 and 20 microns). Here, the measured radiance is (respectively) sensitive to the temperature near the tropopause and sufficient to discern variations in surface topography and emissivity. Our search, as a function of location and time, compares brightness temperatures derived from measurements by the Cassini Composite Infrared Spectrometer (CIRS) and variations of radiance as a function of Titan's rotation derived from ground-based measurements at NASA's Infrared Telescope Facility. Although the variation of the tropopause and zonal near-surface temperatures are fairly homogenous, similar to Courtin and Kim 2002, the meridional distribution of near-surface temperatures varies symmetrically from Equator to pole. While no significant thermal variations suggestive of localized hotspots have yet been observed, such diversity is suggestive of active surface geology, in support of other optical and near-infrared investigations. Although the spatial coverage of the CIRS dataset is severely limited, the approximately 10 degrees field of view (450km at the Equator) is de-convolved somewhat to extract meaningful, sub-pixel maps of Titan's surface. Courtin, R. and Kim, S. (2002). Planet. and Sp. Sci., 50: 309-321. The acquisition of data described here was accomplished through the coordinated effort of Cassini-Huygens project staff, Deep Space Network personnel and the CIRS instrument and science-planning teams with funding provided by the National Research Council, NASA/JPL and NASA/GSFC and the UK Particle Physics and Astronomy council.

Visualizing the near-field coupling and interference of bonding and anti-bonding modes in infrared dimer nanoantennas.

PubMed

Alonso-González, Pablo; Albella, Pablo; Golmar, Federico; Arzubiaga, Libe; Casanova, Félix; Hueso, Luis E; Aizpurua, Javier; Hillenbrand, Rainer

2013-01-14

We directly visualize and identify the capacitive coupling of infrared dimer antennas in the near field by employing scattering-type scanning near-field optical microscopy (s-SNOM). The coupling is identified by (i) resolving the strongly enhanced nano-localized near fields in the antenna gap and by (ii) tracing the red shift of the dimer resonance when compared to the resonance of the single antenna constituents. Furthermore, by modifying the illumination geometry we break the symmetry, providing a means to excite both the bonding and the "dark" anti-bonding modes. By spectrally matching both modes, their interference yields an enhancement or suppression of the near fields at specific locations, which could be useful in nanoscale coherent control applications.

A warm Spitzer survey of the LSST/DES 'Deep drilling' fields

NASA Astrophysics Data System (ADS)

Lacy, Mark; Farrah, Duncan; Brandt, Niel; Sako, Masao; Richards, Gordon; Norris, Ray; Ridgway, Susan; Afonso, Jose; Brunner, Robert; Clements, Dave; Cooray, Asantha; Covone, Giovanni; D'Andrea, Chris; Dickinson, Mark; Ferguson, Harry; Frieman, Joshua; Gupta, Ravi; Hatziminaoglou, Evanthia; Jarvis, Matt; Kimball, Amy; Lubin, Lori; Mao, Minnie; Marchetti, Lucia; Mauduit, Jean-Christophe; Mei, Simona; Newman, Jeffrey; Nichol, Robert; Oliver, Seb; Perez-Fournon, Ismael; Pierre, Marguerite; Rottgering, Huub; Seymour, Nick; Smail, Ian; Surace, Jason; Thorman, Paul; Vaccari, Mattia; Verma, Aprajita; Wilson, Gillian; Wood-Vasey, Michael; Cane, Rachel; Wechsler, Risa; Martini, Paul; Evrard, August; McMahon, Richard; Borne, Kirk; Capozzi, Diego; Huang, Jiashang; Lagos, Claudia; Lidman, Chris; Maraston, Claudia; Pforr, Janine; Sajina, Anna; Somerville, Rachel; Strauss, Michael; Jones, Kristen; Barkhouse, Wayne; Cooper, Michael; Ballantyne, David; Jagannathan, Preshanth; Murphy, Eric; Pradoni, Isabella; Suntzeff, Nicholas; Covarrubias, Ricardo; Spitler, Lee

2014-12-01

We propose a warm Spitzer survey to microJy depth of the four predefined Deep Drilling Fields (DDFs) for the Large Synoptic Survey Telescope (LSST) (three of which are also deep drilling fields for the Dark Energy Survey (DES)). Imaging these fields with warm Spitzer is a key component of the overall success of these projects, that address the 'Physics of the Universe' theme of the Astro2010 decadal survey. With deep, accurate, near-infrared photometry from Spitzer in the DDFs, we will generate photometric redshift distributions to apply to the surveys as a whole. The DDFs are also the areas where the supernova searches of DES and LSST are concentrated, and deep Spitzer data is essential to obtain photometric redshifts, stellar masses and constraints on ages and metallicities for the >10000 supernova host galaxies these surveys will find. This 'DEEPDRILL' survey will also address the 'Cosmic Dawn' goal of Astro2010 through being deep enough to find all the >10^11 solar mass galaxies within the survey area out to z~6. DEEPDRILL will complete the final 24.4 square degrees of imaging in the DDFs, which, when added to the 14 square degrees already imaged to this depth, will map a volume of 1-Gpc^3 at z>2. It will find ~100 > 10^11 solar mass galaxies at z~5 and ~40 protoclusters at z>2, providing targets for JWST that can be found in no other way. The Spitzer data, in conjunction with the multiwavelength surveys in these fields, ranging from X-ray through far-infrared and cm-radio, will comprise a unique legacy dataset for studies of galaxy evolution.

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.

Fabrication of a wide-field NIR integral field unit for SWIMS using ultra-precision cutting

NASA Astrophysics Data System (ADS)

Kitagawa, Yutaro; Yamagata, Yutaka; Morita, Shin-ya; Motohara, Kentaro; Ozaki, Shinobu; Takahashi, Hidenori; Konishi, Masahiro; Kato, Natsuko M.; Kobayakawa, Yutaka; Terao, Yasunori; Ohashi, Hirofumi

2016-07-01

We describe overview of fabrication methods and measurement results of test fabrications of optical surfaces for an integral field unit (IFU) for Simultaneous color Wide-field Infrared Multi-object Spectrograph, SWIMS, which is a first-generation instrument for the University of Tokyo Atacama Observatory 6.5-m telescope. SWIMS-IFU provides entire near-infrared spectrum from 0.9 to 2.5 μm simultaneously covering wider field of view of 17" × 13" compared with current near-infrared IFUs. We investigate an ultra-precision cutting technique to monolithically fabricate optical surfaces of IFU optics such as an image slicer. Using 4- or 5-axis ultra precision machine we compare the milling process and shaper cutting process to find the best way of fabrication of image slicers. The measurement results show that the surface roughness almost satisfies our requirement in both of two methods. Moreover, we also obtain ideal surface form in the shaper cutting process. This method will be adopted to other mirror arrays (i.e. pupil mirror and slit mirror, and such monolithic fabrications will also help us to considerably reduce alignment procedure of each optical elements.

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.

The Hubble Space Telescope Medium Deep Survey with the Wide Field and Planetary Camera. 1: Methodology and results on the field near 3C 273

NASA Technical Reports Server (NTRS)

Griffiths, R. E.; Ratnatunga, K. U.; Neuschaefer, L. W.; Casertano, S.; Im, M.; Wyckoff, E. W.; Ellis, R. S.; Gilmore, G. F.; Elson, R. A. W.; Glazebrook, K.

1994-01-01

We present results from the Medium Deep Survey (MDS), a Key Project using the Hubble Space Telescope (HST). Wide Field Camera (WFC) images of random fields have been taken in 'parallel mode' with an effective resolution of 0.2 sec full width at half maximum (FWHM) in the V(F555W) and I(F785LP) filters. The exposures presented here were targeted on a field away from 3C 273, and resulted in approximately 5 hr integration time in each filter. Detailed morphological structure is seen in galaxy images with total integrated magnitudes down to V approximately = 22.5 and I approximately = 21.5. Parameters are estimated that best fit the observed galaxy images, and 143 objects are identified (including 23 stars) in the field to a fainter limiting magnitude of I approximately = 23.5. We outline the extragalactic goals of the HST Medium Deep Survey, summarize our basic data reduction procedures, and present number (magnitude) counts, a color-magnitude diagram for the field, surface brightness profiles for the brighter galaxies, and best-fit half-light radii for the fainter galaxies as a function of apparent magnitude. A median galaxy half-light radius of 0.4 sec is measured, and the distribution of galaxy sizes versus magnitude is presented. We observe an apparent deficit of galaxies with half-light radii between approximately 0.6 sec and 1.5 sec, with respect to standard no-evolution or mild evolution cosmological models. An apparent excess of compact objects (half-light radii approximately 0.1 sec) is also observed with respect to those models. Finally, we find a small excess in the number of faint galaxy pairs and groups with respect to a random low-redshift field sample.

WISPIR: A Wide-Field Imaging SPectrograph for the InfraRed for the SPICA Observatory

NASA Technical Reports Server (NTRS)

Benford, Dominic J.; Mundy, Lee G.

2010-01-01

We have undertaken a study of a far infrared imaging spectrometer based on a Fourier transform spectrometer that uses well-understood, high maturity optics, cryogenics, and detectors to further our knowledge of the chemical and astrophysical evolution of the Universe as it formed planets, stars, and the variety of galaxy morphologies that we observe today. The instrument, Wide-field Imaging Spectrometer for the InfraRed (WISPIR), would operate on the SPICA observatory, and will feature a spectral range from 35 - 210 microns and a spectral resolving power of R=1,000 to 6,000, depending on wavelength. WISPIR provides a choice of full-field spectral imaging over a 2'x2' field or long-slit spectral imaging along a 2' slit for studies of astrophysical structures in the local and high-redshift Universe. WISPIR in long-slit mode will attain a sensitivity two orders of magnitude better than what is currently available.

The Local Group: the ultimate deep field

NASA Astrophysics Data System (ADS)

Boylan-Kolchin, Michael; Weisz, Daniel R.; Bullock, James S.; Cooper, Michael C.

2016-10-01

Near-field cosmology - using detailed observations of the Local Group and its environs to study wide-ranging questions in galaxy formation and dark matter physics - has become a mature and rich field over the past decade. There are lingering concerns, however, that the relatively small size of the present-day Local Group (˜2 Mpc diameter) imposes insurmountable sample-variance uncertainties, limiting its broader utility. We consider the region spanned by the Local Group's progenitors at earlier times and show that it reaches 3 arcmin ≈ 7 comoving Mpc in linear size (a volume of ≈350 Mpc3) at z = 7. This size at early cosmic epochs is large enough to be representative in terms of the matter density and counts of dark matter haloes with Mvir(z = 7) ≲ 2 × 109 M⊙. The Local Group's stellar fossil record traces the cosmic evolution of galaxies with 103 ≲ M⋆(z = 0)/M⊙ ≲ 109 (reaching M1500 > -9 at z ˜ 7) over a region that is comparable to or larger than the Hubble Ultra-Deep Field (HUDF) for the entire history of the Universe. In the JWST era, resolved stellar populations will probe regions larger than the HUDF and any deep JWST fields, further enhancing the value of near-field cosmology.

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. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Probing the Physical Properties of High Redshift Optically Obscured Galaxies in the Bootes NOAO Deep Wide Field Survey using the Infrared Spectrograph on Spitzer

NASA Astrophysics Data System (ADS)

Higdon, S. J. U.; Weedman, D.; Higdon, J. L.; Houck, J. R.; Soifer, B. T.; Armus, L.; Charmandaris, V.; Herter, T. L.; Brandl, B. R.; Brown, M. J. I.; Dey, A.; Jannuzi, B.; Le Floc'h, E.; Rieke, M.

2004-12-01

We have surveyed a field covering 8.4 degrees2 within the NOAO Deep Wide Field Survey region in Boötes with the Multiband Imaging Photometer on the Spitzer Space Telescope to a limiting 24 um flux density of 0.3 mJy, identifying ˜ 22,000 point sources. Thirty one sources from this survey with F(24 um) > 0.75 mJy , which are optically ``invisible'' (R > 26) or very faint (I > 24) have been observed with the low-resolution modules of the Infrared Spectrograph on SST. The spectra were extracted using the IRS SMART spectral analysis package in order to optimize their signal to noise. A suite of mid-IR spectral templates of well known galaxies, observed as part of the IRS GTO program, is used to perform formal fits to the spectral energy distribution of the Boötes sources. These fits enable us to measure their redshift, to calculate the depth of the 9.7 um silicate feature along with the strength of 7.7 um PAH, as well as to estimate their bolometric luminosities. We compare the mid-IR slope, the measured PAH luminosity, and the optical depth of these sources with those of galaxies in the local Universe. As a result we are able to estimate the contribution of a dust enshrouded active nucleus to the mid-IR and bolometric luminosity of these systems. This work is based [in part] on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through Contract Number 1257184 issued by JPL/Caltech.

The Araucaria Project. The Distance to the Sculptor Group Galaxy NGC 7793 from Near-infrared Photometry of Cepheid Variables

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zgirski, Bartlomiej; Pietrzyński, Grzegorz; Wielgorski, Piotr

Following the earlier discovery of classical Cepheid variables in the Sculptor Group spiral galaxy NGC 7793 from an optical wide-field imaging survey, we have performed deep near-infrared J - and K -band follow-up photometry of a subsample of these Cepheids to derive the distance to this galaxy with a higher accuracy than what was possible from optical photometry alone, by minimizing the effects of reddening and metallicity on the distance result. Combining our new near-infrared period–luminosity relations with previous optical photometry, we obtain a true distance modulus to NGC 7793 of (27.66 ± 0.04) mag (statistical) ±0.07 mag (systematic), i.e.,more » a distance of (3.40 ± 0.17) Mpc. We also determine the mean reddening affecting the Cepheids to be E(B − V) = (0.08 ± 0.02) mag, demonstrating that there is significant dust extinction intrinsic to the galaxy in addition to the small foreground extinction. A comparison of the new, improved Cepheid distance to earlier distance determinations of NGC 7793 from the Tully–Fisher and TRGB methods is in agreement within the reported uncertainties of these previous measurements.« less

The Araucaria Project. The Distance to the Sculptor Group Galaxy NGC 7793 from Near-infrared Photometry of Cepheid Variables

NASA Astrophysics Data System (ADS)

Zgirski, Bartlomiej; Gieren, Wolfgang; Pietrzyński, Grzegorz; Karczmarek, Paulina; Gorski, Marek; Wielgorski, Piotr; Narloch, Weronika; Graczyk, Dariusz; Kudritzki, Rolf-Peter; Bresolin, Fabio

2017-10-01

Following the earlier discovery of classical Cepheid variables in the Sculptor Group spiral galaxy NGC 7793 from an optical wide-field imaging survey, we have performed deep near-infrared J- and K-band follow-up photometry of a subsample of these Cepheids to derive the distance to this galaxy with a higher accuracy than what was possible from optical photometry alone, by minimizing the effects of reddening and metallicity on the distance result. Combining our new near-infrared period-luminosity relations with previous optical photometry, we obtain a true distance modulus to NGC 7793 of (27.66 ± 0.04) mag (statistical) ±0.07 mag (systematic), I.e., a distance of (3.40 ± 0.17) Mpc. We also determine the mean reddening affecting the Cepheids to be E(B - V) = (0.08 ± 0.02) mag, demonstrating that there is significant dust extinction intrinsic to the galaxy in addition to the small foreground extinction. A comparison of the new, improved Cepheid distance to earlier distance determinations of NGC 7793 from the Tully-Fisher and TRGB methods is in agreement within the reported uncertainties of these previous measurements.

Deep Space Wide Area Search Strategies

NASA Astrophysics Data System (ADS)

Capps, M.; McCafferty, J.

There is an urgent need to expand the space situational awareness (SSA) mission beyond catalog maintenance to providing near real-time indications and warnings of emerging events. While building and maintaining a catalog of space objects is essential to SSA, this does not address the threat of uncatalogued and uncorrelated deep space objects. The Air Force therefore has an interest in transformative technologies to scan the geostationary (GEO) belt for uncorrelated space objects. Traditional ground based electro-optical sensors are challenged in simultaneously detecting dim objects while covering large areas of the sky using current CCD technology. Time delayed integration (TDI) scanning has the potential to enable significantly larger coverage rates while maintaining sensitivity for detecting near-GEO objects. This paper investigates strategies of employing TDI sensing technology from a ground based electro-optical telescope, toward providing tactical indications and warnings of deep space threats. We present results of a notional wide area search TDI sensor that scans the GEO belt from three locations: Maui, New Mexico, and Diego Garcia. Deep space objects in the NASA 2030 debris catalog are propagated over multiple nights as an indicative data set to emulate notional uncatalogued near-GEO orbits which may be encountered by the TDI sensor. Multiple scan patterns are designed and simulated, to compare and contrast performance based on 1) efficiency in coverage, 2) number of objects detected, and 3) rate at which detections occur, to enable follow-up observations by other space surveillance network (SSN) sensors. A step-stare approach is also modeled using a dedicated, co-located sensor notionally similar to the Ground-Based Electro-Optical Deep Space Surveillance (GEODSS) tower. Equivalent sensitivities are assumed. This analysis quantifies the relative benefit of TDI scanning for the wide area search mission.

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

PubMed Central

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.

2012-01-01

Abstract. 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. PMID:22463020

Confusion-limited galaxy fields. I - Simulated optical and near-infrared images

NASA Technical Reports Server (NTRS)

Chokshi, Arati; Wright, Edward L.

1988-01-01

Techniques for simulating images of galaxy fields are presented that extend to high redshifts and a surface density of galaxies high enough to produce overlapping images. The observed properties of galaxies and galaxy-ensembles in the 'local' universe are extrapolated to high redshifts using reasonable scenarios for the evolution of galaxies and their spatial distribution. This theoretical framework is then employed with Monte Carlo techniques to create fairly realistic two-dimensional distributions of galaxies plus optical and near-infrared sky images in a variety of model universes, using the appropriate density, luminosity, and angular size versus redshift relations.

A MULTIWAVELENGTH STUDY OF TADPOLE GALAXIES IN THE HUBBLE ULTRA DEEP FIELD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Straughn, Amber N.; Eufrasio, Rafael T.; Gardner, Jonathan P.

2015-12-01

Multiwavelength data are essential in order to provide a complete picture of galaxy evolution and to inform studies of galaxies’ morphological properties across cosmic time. Here we present the results of a multiwavelength investigation of the morphologies of “tadpole” galaxies at intermediate redshift (0.314 < z < 3.175) in the Hubble Ultra Deep Field. These galaxies were previously selected from deep Hubble Space Telescope (HST) F775W data based on their distinct asymmetric knot-plus-tail morphologies. Here we use deep Wide Field Camera 3 near-infrared imaging in addition to the HST optical data in order to study the rest-frame UV/optical morphologies ofmore » these galaxies across the redshift range 0.3 < z < 3.2. This study reveals that the majority of these galaxies do retain their general asymmetric morphology in the rest-frame optical over this redshift range, if not the distinct “tadpole” shape. The average stellar mass of tadpole galaxies is lower than that of field galaxies, with the effect being slightly greater at higher redshift within the errors. Estimated from spectral energy distribution fits, the average age of tadpole galaxies is younger than that of field galaxies in the lower-redshift bin, and the average metallicity is lower (whereas the specific star formation rate for tadpoles is roughly the same as field galaxies across the redshift range probed here). These average effects combined support the conclusion that this subset of galaxies is in an active phase of assembly, either late-stage merging or cold gas accretion causing localized clumpy star formation.« less

Graphene-Based Platform for Infrared Near-Field Nanospectroscopy of Water and Biological Materials in an Aqueous Environment.

PubMed

Khatib, Omar; Wood, Joshua D; McLeod, Alexander S; Goldflam, Michael D; Wagner, Martin; Damhorst, Gregory L; Koepke, Justin C; Doidge, Gregory P; Rangarajan, Aniruddh; Bashir, Rashid; Pop, Eric; Lyding, Joseph W; Thiemens, Mark H; Keilmann, Fritz; Basov, D N

2015-08-25

Scattering scanning near-field optical microscopy (s-SNOM) has emerged as a powerful nanoscale spectroscopic tool capable of characterizing individual biomacromolecules and molecular materials. However, applications of scattering-based near-field techniques in the infrared (IR) to native biosystems still await a solution of how to implement the required aqueous environment. In this work, we demonstrate an IR-compatible liquid cell architecture that enables near-field imaging and nanospectroscopy by taking advantage of the unique properties of graphene. Large-area graphene acts as an impermeable monolayer barrier that allows for nano-IR inspection of underlying molecular materials in liquid. Here, we use s-SNOM to investigate the tobacco mosaic virus (TMV) in water underneath graphene. We resolve individual virus particles and register the amide I and II bands of TMV at ca. 1520 and 1660 cm(-1), respectively, using nanoscale Fourier transform infrared spectroscopy (nano-FTIR). We verify the presence of water in the graphene liquid cell by identifying a spectral feature associated with water absorption at 1610 cm(-1).

Introducing cymantrene labels into scattering scanning near-field infrared microscopy.

PubMed

Kopf, Ilona; N'Dongo, Harmel W Peindy; Ballout, Fouad; Schatzschneider, Ulrich; Bründermann, Erik; Havenith, Martina

2012-11-07

In this paper we investigate metal-organic compounds as infrared (IR) active labels by scattering scanning near-field infrared microscopy (IR s-SNOM, often also abbreviated as s-SNIM) with a lateral resolution of 90 × 90 nm(2). Tailor-made IR spectroscopic probes based on cymantrene (CpMn(CO)(3) with Cp = η(5)-C(5)H(5)) conjugated to a cysteine-modified pseudoneurotensin (pNT-Cys-OH) peptide were prepared by automated microwave-assisted solid phase peptide synthesis (SPPS) and characterized by HPLC, ESI-MS and IR. Well-defined patterned self-assembled monolayers on a gold surface were prepared by microcontact printing of 1-octadecanethiol (ODT) followed by additional incubation in ethanolic solution of the cymantrene-peptide derivative. The self-assembled monolayers have been evidenced by infrared reflection absorption spectroscopy (IRRAS) and AFM. CO laser source radiation was tuned (1944, 1900, 1798 and 1658 cm(-1)) for imaging contrast with good matching correlation between spectroscopic and topographic patterns at specific characteristic metal carbonyl and amide bands (1944 cm(-1) (λ = 5.14 μm) and 1658 cm(-1) (λ = 6.03 μm)). Cymantrene probes provide an attractive method to tag a unique spectroscopic feature on any bio(macro)molecule. Introducing such probes into super-resolution IR s-SNOM will enable molecular tracking and distribution studies even in complex biological systems.

Wide-field Infrared Polarimetry of the ρ Ophiuchi Cloud Core

NASA Astrophysics Data System (ADS)

Kwon, Jungmi; Tamura, Motohide; Hough, James H.; Nakajima, Yasushi; Nishiyama, Shogo; Kusakabe, Nobuhiko; Nagata, Tetsuya; Kandori, Ryo

2015-09-01

We conducted wide and deep simultaneous JHKs-band imaging polarimetry of the ρ Ophiuchi cloud complex. Aperture polarimetry in the JHKs band was conducted for 2136 sources in all three bands, of which 322 sources have significant polarizations in all the JHKs bands and have been used for a discussion of the core magnetic fields. There is a positive correlation between degrees of polarization and H - Ks color up to H - Ks ≈ 3.5. The magnetic field structures in the core region are revealed up to at least AV ≈ 47 mag and are unambiguously defined in each sub-region (core) of Oph-A, Oph-B, Oph-C, Oph-E, Oph-F, and Oph-AC. Their directions, degrees of polarization, and polarization efficiencies differ but their changes are gradual; thus, the magnetic fields appear to be connected from core to core, rather than as a simple overlap of the different cloud core components. Comparing our results with the large-scale field structures obtained from previous optical polarimetric studies, we suggest that the magnetic field structures in the core were distorted by the cluster formation in this region, which may have been induced by shock compression due to wind/radiation from the Scorpius-Centaurus association.

Analysis of near-field components of a plasmonic optical antenna and their contribution to quantum dot infrared photodetector enhancement.

PubMed

Gu, Guiru; Vaillancourt, Jarrod; Lu, Xuejun

2014-10-20

In this paper, we analyze near-field vector components of a metallic circular disk array (MCDA) plasmonic optical antenna and their contribution to quantum dot infrared photodetector (QDIP) enhancement. The near-field vector components of the MCDA optical antenna and their distribution in the QD active region are simulated. The near-field overlap integral with the QD active region is calculated at different wavelengths and compared with the QDIP enhancement spectrum. The x-component (E(x)) of the near-field vector shows a larger intensity overlap integral and stronger correlation with the QDIP enhancement than E(z) and thus is determined to be the major near-field component to the QDIP enhancement.

Update on the Wide-field Infrared Survey Explorer (WISE)

NASA Technical Reports Server (NTRS)

Mainzer, Amanda K.; Eisenhardt, Peter; Wright, Edward L.; Liu, Feng-Chuan; Irace, William; Heinrichsen, Ingolf; Cutri, Roc; Duval, Valerie

2006-01-01

The Wide-field Infrared Survey Explorer (WISE), a NASA MIDEX mission, will survey the entire sky in four bands from 3.3 to 23 microns with a sensitivity 1000 times greater than the IRAS survey. The WISE survey will extend the Two Micron All Sky Survey into the thermal infrared and will provide an important catalog for the James Webb Space Telescope. Using 1024(sup 2) HgCdTe and Si:As arrays at 3.3, 4.7, 12 and 23 microns, WISE will find the most luminous galaxies in the universe, the closest stars to the Sun, and it will detect most of the main belt asteroids larger than 3 km. The single WISE instrument consists of a 40 cm diamond-turned aluminum afocal telescope, a two-stage solid hydrogen cryostat, a scan mirror mechanism, and reimaging optics giving 5 resolution (full-width-half-maximum). The use of dichroics and beamsplitters allows four color images of a 47' x47' field of view to be taken every 8.8 seconds, synchronized with the orbital motion to provide total sky coverage with overlap between revolutions. WISE will be placed into a Sun-synchronous polar orbit on a Delta 7320-10 launch vehicle. The WISE survey approach is simple and efficient. The three-axis-stabilized spacecraft rotates at a constant rate while the scan mirror freezes the telescope line of sight during each exposure. WISE has completed its mission Preliminary Design Review and its NASA Confirmation Review, and the project is awaiting confirmation from NASA to proceed to the Critical Design phase. Much of the payload hardware is now complete, and assembly of the payload will occur over the next year. WISE is scheduled to launch in late 2009; the project web site can be found at www.wise.ssl.berkeley.edu.

THE FIRST HUNDRED BROWN DWARFS DISCOVERED BY THE WIDE-FIELD INFRARED SURVEY EXPLORER (WISE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davy Kirkpatrick, J.; Gelino, Christopher R.; Griffith, Roger L.

2011-12-01

We present ground-based spectroscopic verification of 6 Y dwarfs (see also Cushing et al.), 89 T dwarfs, 8 L dwarfs, and 1 M dwarf identified by the Wide-field Infrared Survey Explorer (WISE). Eighty of these are cold brown dwarfs with spectral types {>=}T6, six of which have been announced earlier by Mainzer et al. and Burgasser et al. We present color-color and color-type diagrams showing the locus of M, L, T, and Y dwarfs in WISE color space. Near-infrared and, in a few cases, optical spectra are presented for these discoveries. Near-infrared classifications as late as early Y are presentedmore » and objects with peculiar spectra are discussed. Using these new discoveries, we are also able to extend the optical T dwarf classification scheme from T8 to T9. After deriving an absolute WISE 4.6 {mu}m (W2) magnitude versus spectral type relation, we estimate spectrophotometric distances to our discoveries. We also use available astrometric measurements to provide preliminary trigonometric parallaxes to four of our discoveries, which have types of L9 pec (red), T8, T9, and Y0; all of these lie within 10 pc of the Sun. The Y0 dwarf, WISE 1541-2250, is the closest at 2.8{sup +1.3}{sub -0.6} pc; if this 2.8 pc value persists after continued monitoring, WISE 1541-2250 will become the seventh closest stellar system to the Sun. Another 10 objects, with types between T6 and >Y0, have spectrophotometric distance estimates also placing them within 10 pc. The closest of these, the T6 dwarf WISE 1506+7027, is believed to fall at a distance of {approx}4.9 pc. WISE multi-epoch positions supplemented with positional info primarily from the Spitzer/Infrared Array Camera allow us to calculate proper motions and tangential velocities for roughly one-half of the new discoveries. This work represents the first step by WISE to complete a full-sky, volume-limited census of late-T and Y dwarfs. Using early results from this census, we present preliminary, lower limits to the space

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

The Wide Field X-ray Telescope Mission

NASA Astrophysics Data System (ADS)

Murray, Stephen S.; WFXT Team

2010-01-01

To explore the high-redshift Universe to the era of galaxy formation requires an X-ray survey that is both sensitive and extensive, which complements deep wide-field surveys at other wavelengths. The Wide-Field X-ray Telescope (WFXT) is designed to be two orders of magnitude more effective than previous and planned X-ray missions for surveys. WFXT consists of three co-aligned wide-field X-ray telescopes with a 1 sq. deg. field of view and <10 arc sec (goal of 5 arc sec) angular resolution over the full field. With nearly ten times Chandra's collecting area and more than ten times Chandra's field of view, WFXT will perform sensitive deep surveys that will discover and characterize extremely large populations of high redshift AGN and galaxy clusters. In five years, WFXT will perform three extragalactic surveys: 1) 20,000 sq. deg. of extragalactic sky at 100-1000 times the sensitivity, and twenty times better angular resolution than the ROSAT All Sky Survey; 2) 3000 sq.deg. to deep Chandra sensitivity; and 3) 100 sq.deg. to the deepest Chandra sensitivity. WFXT will generate a legacy dataset of >500,000 galaxy clusters to redshifts about 2, measuring redshift, gas abundance and temperature for a significant fraction of them, and a sample of more than 10 million AGN to redshifts > 6, many with X-ray spectra sufficient to distinguish obscured from unobscured quasars. These surveys will address fundamental questions of how supermassive black holes grow and influence the evolution of the host galaxy and how clusters form and evolve, as well as providing large samples of massive clusters that can be used in cosmological studies. WFXT surveys will map systems spanning many square degrees including Galactic star forming regions, the Magellanic Clouds and the Virgo Cluster. WFXT data will become public through annual Data Releases that will constitute a vast scientific legacy.

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.

Gradual plasmon evolution and huge infrared near-field enhancement of metallic bridged nanoparticle dimers.

PubMed

Huang, Yu; Ma, Lingwei; Hou, Mengjing; Xie, Zheng; Zhang, Zhengjun

2016-01-28

By three-dimensional (3D) finite element method (FEM) plasmon mapping, gradual plasmon evolutions of both bonding dipole plasmon (BDP) and charge transfer plasmon (CTP) modes are visualized. In particular, the evolved BDP mode provides a physical insight into the rapid degeneration of electromagnetic hot spots in practical applications, while the rising CTP mode enables a huge near-field enhancement for potential plasmonic devices at infrared wavelengths.

Morphology and Structure of Ultraluminous Infrared Galaxies at z ∼ 2 in the EGS Field

NASA Astrophysics Data System (ADS)

Fang, Guan-Wen; Ma, Zhong-Yang; Chen, Yang; Kong, Xu

2015-04-01

Using the high-resolution F160W images observed by the HST WFC3 (Hubble Space Telescope Wide Field Camera 3) in the CANDELS-EGS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Extended Groth Strip) field, we have studied the morphological and structural features of 9 ultraluminous infrared galaxies (ULIRGs) at z ∼ 2. We find a wide range of morphological diversity for these ULIRGs, from ellipsoids to multiple bright nuclei or diffuse structures, e.g., the double nuclei, gaseous bridges, dual asym- metries, irregular or elliptical structures. In order to study the morphology of these ULIRGs quantitatively, their morphological parameters (the Gini coeffcient G and moment index M20) are measured in the rest-frame optical wave- band. Compared with the low-redshift counterparts, the high-redshift ULIRGs show a smaller value of G and a larger value of M20, indicating a less concen- tricity and a larger asymmetry of the stellar population distribution in these ULIRGs. Based on a 2-D fitting of the brightness profiles of these ULIRGs, we have derived their effective radii, which are distributed in a range from 2.4 to kpc, with a mean value of (3.9 ± 1.1) kpc. Moreover, we find that in average the sizes of the high-redshift ULIRGs are one to two times smaller than those of the nearby star-forming galaxies of analogous stellar mass. Our results are consistent with those of other studies under the similar conditions of redshift and infrared luminosity.

Feasibility of field portable near infrared (NIR) spectroscopy to determine cyanide concentrations in soil

NASA Astrophysics Data System (ADS)

Sut, Magdalena; Fischer, Thomas; Repmann, Frank; Raab, Thomas

2013-04-01

In Germany, at more than 1000 sites, soil is polluted with an anthropogenic contaminant in form of iron-cyanide complexes. These contaminations are caused by former Manufactured Gas Plants (MGPs), where electricity for lighting was produced in the process of coal gasification. The production of manufactured gas was restrained in 1950, which caused cessation of MGPs. Our study describes the application of Polychromix Handheld Field Portable Near-Infrared (NIR) Analyzer to predict the cyanide concentrations in soil. In recent times, when the soil remediation is of major importance, there is a need to develop rapid and non-destructive methods for contaminant determination in the field. In situ analysis enables determination of 'hot spots', is cheap and time saving in comparison to laboratory methods. This paper presents a novel usage of NIR spectroscopy, where a calibration model was developed, using multivariate calibration algorithms, in order to determine NIR spectral response to the cyanide concentration in soil samples. As a control, the contaminant concentration was determined using conventional Flow Injection Analysis (FIA). The experiments revealed that portable near-infrared spectrometers could be a reliable device for identification of contamination 'hot spots', where cyanide concentration are higher than 2400 mg kg-1 in the field and >1750 mg kg-1 after sample preparation in the laboratory, but cannot replace traditional laboratory analyses due to high limits of detection.

THE ARAUCARIA PROJECT: THE DISTANCE TO THE SCULPTOR GALAXY NGC 247 FROM NEAR-INFRARED PHOTOMETRY OF CEPHEID VARIABLES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gieren, Wolfgang; Pietrzynski, Grzegorz; Szewczyk, Olaf

2009-08-01

We have obtained deep near-infrared images in J and K filters of four fields in the Sculptor Group spiral galaxy NGC 247 with the ESO VLT and Infrared Spectrometer and Array Camera. For a sample of 10 Cepheids in these fields, previously discovered by GarcIa-Varela et al. from optical wide-field images, we have determined mean J and K magnitudes and have constructed the period-luminosity (PL) relations in these bands. Using the near-infrared PL relations together with those in the optical V and I bands, we have determined a true distance modulus for NGC 247 of 27.64 mag, with a randommore » uncertainty of {+-}2% and a systematic uncertainty of {approx}4% which is dominated by the effect of unresolved stars on the Cepheid photometry. The mean reddening affecting the NGC 247 Cepheids of E(B - V) = 0.18 {+-} 0.02 mag is mostly produced in the host galaxy itself and is significantly higher than what was found in the previous optical Cepheid studies in NGC 247 of our own group, and Madore et al., leading to a 7% decrease in the previous optical Cepheid distance. As in other studies of our project, the distance modulus of NGC 247 we report is tied to an assumed Large Magellanic Cloud distance modulus of 18.50. Comparison with other distance measurements to NGC 247 shows that the present IR-based Cepheid distance is the most accurate among these determinations. With a distance of 3.4 Mpc, NGC 247 is about 1.5 Mpc more distant than NGC 55 and NGC 300, two other Sculptor Group spirals analyzed before with the same technique by our group.« less

WIDE-FIELD INFRARED POLARIMETRY OF THE ρ OPHIUCHI CLOUD CORE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwon, Jungmi; Tamura, Motohide; Kusakabe, Nobuhiko

2015-09-15

We conducted wide and deep simultaneous JHK{sub s}-band imaging polarimetry of the ρ Ophiuchi cloud complex. Aperture polarimetry in the JHK{sub s} band was conducted for 2136 sources in all three bands, of which 322 sources have significant polarizations in all the JHK{sub s} bands and have been used for a discussion of the core magnetic fields. There is a positive correlation between degrees of polarization and H − K{sub s} color up to H − K{sub s} ≈ 3.5. The magnetic field structures in the core region are revealed up to at least A{sub V} ≈ 47 mag andmore » are unambiguously defined in each sub-region (core) of Oph-A, Oph-B, Oph-C, Oph-E, Oph-F, and Oph-AC. Their directions, degrees of polarization, and polarization efficiencies differ but their changes are gradual; thus, the magnetic fields appear to be connected from core to core, rather than as a simple overlap of the different cloud core components. Comparing our results with the large-scale field structures obtained from previous optical polarimetric studies, we suggest that the magnetic field structures in the core were distorted by the cluster formation in this region, which may have been induced by shock compression due to wind/radiation from the Scorpius–Centaurus association.« less

Impact of the plasmonic near- and far-field resonance-energy shift on the enhancement of infrared vibrational signals.

PubMed

Vogt, Jochen; Huck, Christian; Neubrech, Frank; Toma, Andrea; Gerbert, David; Pucci, Annemarie

2015-09-07

We report on the impact of the differing spectral near- and far-field properties of resonantly excited gold nanoantennas on the vibrational signal enhancement in surface-enhanced infrared absorption (SEIRA). The knowledge on both spectral characteristics is of considerable importance for the optimization of plasmonic nanostructures for surface-enhanced spectroscopy techniques. From infrared micro-spectroscopic measurements, we simultaneously obtain spectral information on the plasmonic far-field response and, via SEIRA spectroscopy of a test molecule, on the near-field enhancement. The molecular test layer of 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) was deposited on the surface of gold nanoantennas with different lengths and thus different far-field resonance energies. We carefully studied the Fano-type vibrational lines in a broad spectral window, in particular, how the various vibrational signals are enhanced in relation to the ratio of the far-field plasmonic resonance and the molecular vibrational frequencies. As a detailed experimental proof of former simulation studies, we show the clearly red-shifted maximum SEIRA enhancement compared to the far-field resonance.

Application of near-infrared image processing in agricultural engineering

NASA Astrophysics Data System (ADS)

Chen, Ming-hong; Zhang, Guo-ping; Xia, Hongxing

2009-07-01

Recently, with development of computer technology, the application field of near-infrared image processing becomes much wider. In this paper the technical characteristic and development of modern NIR imaging and NIR spectroscopy analysis were introduced. It is concluded application and studying of the NIR imaging processing technique in the agricultural engineering in recent years, base on the application principle and developing characteristic of near-infrared image. The NIR imaging would be very useful in the nondestructive external and internal quality inspecting of agricultural products. It is important to detect stored-grain insects by the application of near-infrared spectroscopy. Computer vision detection base on the NIR imaging would be help to manage food logistics. Application of NIR imaging promoted quality management of agricultural products. In the further application research fields of NIR image in the agricultural engineering, Some advices and prospect were put forward.

Wide angle and narrow-band asymmetric absorption in visible and near-infrared regime through lossy Bragg stacks

PubMed Central

Shu, Shiwei; Zhan, Yawen; Lee, Chris; Lu, Jian; Li, Yang Yang

2016-01-01

Absorber is an important component in various optical devices. Here we report a novel type of asymmetric absorber in the visible and near-infrared spectrum which is based on lossy Bragg stacks. The lossy Bragg stacks can achieve near-perfect absorption at one side and high reflection at the other within the narrow bands (several nm) of resonance wavelengths, whereas display almost identical absorption/reflection responses for the rest of the spectrum. Meanwhile, this interesting wavelength-selective asymmetric absorption behavior persists for wide angles, does not depend on polarization, and can be ascribed to the lossy characteristics of the Bragg stacks. Moreover, interesting Fano resonance with easily tailorable peak profiles can be realized using the lossy Bragg stacks. PMID:27251768

Deepest Wide-Field Colour Image in the Southern Sky

NASA Astrophysics Data System (ADS)

2003-01-01

January 1999 when the WFI instrument was first installed (cf. ESO PR 02/99 ) and ending in October 2002. Altogether, nearly 50 hours of exposure were collected in the three filters combined here, cf. the technical information below. Although it is possible to identify more than 100,000 galaxies in the image - some of which are shown in PR Photo 02b/03 - it is still remarkably "empty" by astronomical standards. Even the brightest stars in the field (of visual magnitude 9) can hardly be seen by human observers with binoculars. In fact, the area density of bright, nearby galaxies is only half of what it is in "normal" sky fields. Comparatively empty fields like this one provide an unsually clear view towards the distant regions in the universe and thus open a window towards the earliest cosmic times . Research projects in the Chandra Deep Field South ESO PR Photo 02c/03 ESO PR Photo 02c/03 [Preview - JPEG: 400 x 513 pix - 112k] [Normal - JPEG: 800 x 1026 pix - 1.2M] [Full-Res - JPEG: 1717 x 2201 pix - 5.5M] ESO PR Photo 02d/03 ESO PR Photo 02d/03 [Preview - JPEG: 400 x 469 pix - 112k] [Normal - JPEG: 800 x 937 pix - 1.0M] [Full-Res - JPEG: 2545 x 2980 pix - 10.7M] Caption : PR Photo 02c-d/03 shows two sky fields within the WFI image of CDF-S, reproduced at full (pixel) size to illustrate the exceptional information richness of these data. The subfields measure 6.8 x 7.8 arcmin 2 (1717 x 1975 pixels) and 10.1 x 10.5 arcmin 2 (2545 x 2635 pixels), respectively. North is up and East is left. Technical information is available below. Astronomers from different teams and disciplines have been quick to join forces in a world-wide co-ordinated effort around the Chandra Deep Field South. Observations of this area are now being performed by some of the most powerful astronomical facilities and instruments. They include space-based X-ray and infrared observations by the ESA XMM-Newton , the NASA CHANDRA , Hubble Space Telescope (HST) and soon SIRTF (scheduled for launch in a few

Characterization of semiconductor materials using synchrotron radiation-based near-field infrared microscopy and nano-FTIR spectroscopy.

PubMed

Hermann, Peter; Hoehl, Arne; Ulrich, Georg; Fleischmann, Claudia; Hermelink, Antje; Kästner, Bernd; Patoka, Piotr; Hornemann, Andrea; Beckhoff, Burkhard; Rühl, Eckart; Ulm, Gerhard

2014-07-28

We describe the application of scattering-type near-field optical microscopy to characterize various semiconducting materials using the electron storage ring Metrology Light Source (MLS) as a broadband synchrotron radiation source. For verifying high-resolution imaging and nano-FTIR spectroscopy we performed scans across nanoscale Si-based surface structures. The obtained results demonstrate that a spatial resolution below 40 nm can be achieved, despite the use of a radiation source with an extremely broad emission spectrum. This approach allows not only for the collection of optical information but also enables the acquisition of near-field spectral data in the mid-infrared range. The high sensitivity for spectroscopic material discrimination using synchrotron radiation is presented by recording near-field spectra from thin films composed of different materials used in semiconductor technology, such as SiO2, SiC, SixNy, and TiO2.

Biocompatible near-infrared fluorescent nanoparticles for macro and microscopic in vivo functional bioimaging

PubMed Central

Chu, Liliang; Wang, Shaowei; Li, Kanghui; Xi, Wang; Zhao, Xinyuan; Qian, Jun

2014-01-01

Near-infrared (NIR) imaging technology has been widely used for biomedical research and applications, since it can achieve deep penetration in biological tissues due to less absorption and scattering of NIR light. In our research, polymer nanoparticles with NIR fluorophores doped were synthesized. The morphology, absorption/emission features and chemical stability of the fluorescent nanoparticles were characterized, separately. NIR fluorescent nanoparticles were then utilized as bright optical probes for macro in vivo imaging of mice, including sentinel lymph node (SLN) mapping, as well as distribution and excretion monitoring of nanoparticles in animal body. Furthermore, we applied the NIR fluorescent nanoparticles in in vivo microscopic bioimaging via a confocal microscope. Under the 635 nm-CW excitation, the blood vessel architecture in the ear and the brain of mice, which were administered with nanoparticles, was visualized very clearly. The imaging depth of our one-photon microscopy, which was assisted with NIR fluorescent nanoprobes, can reach as deep as 500 μm. Our experiments show that NIR fluorescent nanoparticles have great potentials in various deep-tissue imaging applications. PMID:25426331

Rapid Measurement of Soil Carbon in Rice Paddy Field of Lombok Island Indonesia Using Near Infrared Technology

NASA Astrophysics Data System (ADS)

Kusumo, B. H.; Sukartono, S.; Bustan, B.

2018-02-01

Measuring soil organic carbon (C) using conventional analysis is tedious procedure, time consuming and expensive. It is needed simple procedure which is cheap and saves time. Near infrared technology offers rapid procedure as it works based on the soil spectral reflectance and without any chemicals. The aim of this research is to test whether this technology able to rapidly measure soil organic C in rice paddy field. Soil samples were collected from rice paddy field of Lombok Island Indonesia, and the coordinates of the samples were recorded. Parts of the samples were analysed using conventional analysis (Walkley and Black) and some other parts were scanned using near infrared spectroscopy (NIRS) for soil spectral collection. Partial Least Square Regression (PLSR) Models were developed using data of soil C analysed using conventional analysis and data from soil spectral reflectance. The models were moderately successful to measure soil C in rice paddy field of Lombok Island. This shows that the NIR technology can be further used to monitor the C change in rice paddy soil.

Looking Deep with Infrared Eyes

NASA Astrophysics Data System (ADS)

2006-07-01

Today, British astronomers are releasing the first data from the largest and most sensitive survey of the heavens in infrared light to the ESO user community. The UKIRT Infrared Deep Sky Survey (UKIDSS) has completed the first of seven years of data collection, studying objects that are too faint to see at visible wavelengths, such as very distant or very cool objects. New data on young galaxies is already challenging current thinking on galaxy formation, revealing galaxies that are massive at a much earlier stage of development than expected. These first science results already show how powerful the full survey will be at finding rare objects that hold vital clues to how stars and galaxies in our Universe formed. UKIDSS will make an atlas of large areas of the sky in the infrared. The data become available to the entire ESO user community immediately after they are entered into the archive [2]. Release to the world follows 18 months after each release to ESO. "Astronomers across Europe will jump on these exciting new data. We are moving into new territory - our survey is both wide and deep, so we are mapping huge volumes of space. That's how we will locate rare objects - the very nearest and smallest stars, and young galaxies at the edge of the universe," said Andy Lawrence from the University of Edinburgh, UKIDSS Principal Investigator. The UKIDSS data are collected by the United Kingdom Infrared Telescope [3] situated near the summit of Mauna Kea in Hawaii using the Wide Field Camera (WFCAM) built by the United Kingdom Astronomy Technology Centre (UKATC) in Edinburgh. WFCAM is the most powerful infrared imager in the world, generating enormous amounts of data - 150 gigabytes per night (equivalent to more than 200 CDs) - and approximately 10.5 Terabytes in total so far (or 15,000 CDs). Mark Casali, now at ESO, was the Project Scientist in charge of the WFCAM instrument construction at the UKATC. "WFCAM was a bold technological undertaking," said Mark Casali

Scattering-type scanning near-field optical microscopy with reconstruction of vertical interaction

PubMed Central

Wang, Le; Xu, Xiaoji G.

2015-01-01

Scattering-type scanning near-field optical microscopy provides access to super-resolution spectroscopic imaging of the surfaces of a variety of materials and nanostructures. In addition to chemical identification, it enables observations of nano-optical phenomena, such as mid-infrared plasmons in graphene and phonon polaritons in boron nitride. Despite the high lateral spatial resolution, scattering-type near-field optical microscopy is not able to provide characteristics of near-field responses in the vertical dimension, normal to the sample surface. Here, we present an accurate and fast reconstruction method to obtain vertical characteristics of near-field interactions. For its first application, we investigated the bound electromagnetic field component of surface phonon polaritons on the surface of boron nitride nanotubes and found that it decays within 20 nm with a considerable phase change in the near-field signal. The method is expected to provide characterization of the vertical field distribution of a wide range of nano-optical materials and structures. PMID:26592949

Nonsequential double ionization with mid-infrared laser fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Ying -Bin; Wang, Xu; Yu, Ben -Hai

Using a full-dimensional Monte Carlo classical ensemble method, we present a theoretical study of atomic nonsequential double ionization (NSDI) with mid-infrared laser fields, and compare with results from near-infrared laser fields. Unlike single-electron strong-field processes, double ionization shows complex and unexpected interplays between the returning electron and its parent ion core. As a result of these interplays, NSDI for mid-IR fields is dominated by second-returning electron trajectories, instead of first-returning trajectories for near-IR fields. Here, some complex NSDI channels commonly happen with near-IR fields, such as the recollision-excitation-with-subsequent-ionization (RESI) channel, are virtually shut down by mid-IR fields. Besides, the finalmore » energies of the two electrons can be extremely unequal, leading to novel e-e momentum correlation spectra that can be measured experimentally.« less

Nonsequential double ionization with mid-infrared laser fields

DOE PAGES

Li, Ying -Bin; Wang, Xu; Yu, Ben -Hai; ...

2016-11-18

Using a full-dimensional Monte Carlo classical ensemble method, we present a theoretical study of atomic nonsequential double ionization (NSDI) with mid-infrared laser fields, and compare with results from near-infrared laser fields. Unlike single-electron strong-field processes, double ionization shows complex and unexpected interplays between the returning electron and its parent ion core. As a result of these interplays, NSDI for mid-IR fields is dominated by second-returning electron trajectories, instead of first-returning trajectories for near-IR fields. Here, some complex NSDI channels commonly happen with near-IR fields, such as the recollision-excitation-with-subsequent-ionization (RESI) channel, are virtually shut down by mid-IR fields. Besides, the finalmore » energies of the two electrons can be extremely unequal, leading to novel e-e momentum correlation spectra that can be measured experimentally.« less

[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.

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

Imaging secondary structure of individual amyloid fibrils of a β2-microglobulin fragment using near-field infrared spectroscopy.

PubMed

Paulite, Melissa; Fakhraai, Zahra; Li, Isaac T S; Gunari, Nikhil; Tanur, Adrienne E; Walker, Gilbert C

2011-05-18

Amyloid fibril diseases are characterized by the abnormal production of aggregated proteins and are associated with many types of neuro- and physically degenerative diseases. X-ray diffraction techniques, solid-state magic-angle spinning NMR spectroscopy, circular dichroism (CD) spectroscopy, and transmission electron microscopy studies have been utilized to detect and examine the chemical, electronic, material, and structural properties of amyloid fibrils at up to angstrom spatial resolution. However, X-ray diffraction studies require crystals of the fibril to be analyzed, while other techniques can only probe the bulk solution or solid samples. In the work reported here, apertureless near-field scanning infrared microscopy (ANSIM) was used to probe the secondary structure of individual amyloid fibrils made from an in vitro solution. Simultaneous topographic and infrared images of individual amyloid fibrils synthesized from the #21-31 peptide fragment of β(2)-microglobulin were acquired. Using this technique, IR spectra of the amyloid fibrils were obtained with a spatial resolution of less than 30 nm. It is observed that the experimental scattered field spectrum correlates strongly with that calculated using the far-field absorption spectrum. The near-field images of the amyloid fibrils exhibit much lower scattering of the IR radiation at approximately 1630 cm(-1). In addition, the near-field images also indicate that composition and/or structural variations among individual amyloid fibrils were present. © 2011 American Chemical Society

Wide-Field InfraRed Survey Telescope (WFIRST) Slitless Spectrometer: Design, Prototype, and Results

NASA Technical Reports Server (NTRS)

Gong, Qian; Content, David; Dominguez, Margaret; Emmett, Thomas; Griesmann, Ulf; Hagopian, John; Kruk, Jeffrey; Marx, Catherine; Pasquale, Bert; Wallace, Thomas;

The cosmic infrared background experiment-2 (CIBER-2) for studying the near-infrared extragalactic background light

NASA Astrophysics Data System (ADS)

Shirahata, Mai; Arai, Toshiaki; Battle, John; Bock, James; Cooray, Asantha; Enokuchi, Akito; Hristov, Viktor; Kanai, Yoshikazu; Kim, Min Gyu; Korngut, Phillip; Lanz, Alicia; Lee, Dae-Hee; Mason, Peter; Matsumoto, Toshio; Matsuura, Shuji; Morford, Tracy; Ohnishi, Yosuke; Park, Won-Kee; Sano, Kei; Takeyama, Norihide; Tsumura, Kohji; Wada, Takehiko; Wang, Shiang-Yu; Zemcov, Michael

2016-07-01

We present the current status of the Cosmic Infrared Background ExpeRiment-2 (CIBER-2) project, whose goal is to make a rocket-borne measurement of the near-infrared Extragalactic Background Light (EBL), under a collaboration with U.S.A., Japan, South Korea, and Taiwan. The EBL is the integrated light of all extragalactic sources of emission back to the early Universe. At near-infrared wavelengths, measurement of the EBL is a promising way to detect the diffuse light from the first collapsed structures at redshift z˜10, which are impossible to detect as individual sources. However, recently, the intra-halo light (IHL) model is advocated as the main contribution to the EBL, and our new result of the EBL fluctuation from CIBER-1 experiment is also supporting this model. In this model, EBL is contributed by accumulated light from stars in the dark halo regions of low- redshift (z<2) galaxies, those were tidally stripped by the interaction of satellite dwarf galaxies. Thus, in order to understand the origin of the EBL, both the spatial fluctuation observations with multiple wavelength bands and the absolute spectroscopic observations for the EBL are highly required. After the successful initial CIBER- 1 experiment, we are now developing a new instrument CIBER-2, which is comprised of a 28.5-cm aluminum telescope and three broad-band, wide-field imaging cameras. The three wide-field (2.3×2.3 degrees) imaging cameras use the 2K×2K HgCdTe HAWAII-2RG arrays, and cover the optical and near-infrared wavelength range of 0.5-0.9 μm, 1.0-1.4 μm and 1.5-2.0 μm, respectively. Combining a large area telescope with the high sensitivity detectors, CIBER-2 will be able to measure the spatial fluctuations in the EBL at much fainter levels than those detected in previous CIBER-1 experiment. Additionally, we will use a linear variable filter installed just above the detectors so that a measurement of the absolute spectrum of the EBL is also possible. In this paper, the scientific

Tunable magnetization of infrared epsilon-near-zero media via field-effect modulation

NASA Astrophysics Data System (ADS)

Salary, Mohammad Mahdi; Mosallaei, Hossein

2018-04-01

In this letter, we demonstrate that field effect modulation enables electrical tuning of the effective permeability of epsilon-near-zero (ENZ) media at infrared frequencies. In particular, hexagonal silicon carbide (6H-SiC) is incorporated as an epsilon-near-zero host in a gated 6H-SiC/SiO2/Si heterostructure. The change in the applied voltage leads to a change in the carrier concentration of the accumulation layer formed at the interface of 6H-SiC and SiO2 which can alter the effective permeability of the heterostructure by virtue of the photonic doping effect. We will rigorously model and analyze the structure by linking charge transport and electromagnetic models. The presented mechanism allows for tuning the impedance and magnetization of ENZ materials in real-time while capturing extreme cases of epsilon-and-mu-near-zero and magnetic conductor. As such, it can be used for various applications such as real-time engineering of thermal emission, dynamic switching, reconfigurable tunneling, and holography.

Near-infrared integral field spectroscopy of star-forming galaxies

NASA Technical Reports Server (NTRS)

Dale, D. A.; Roussel, H.; Contursi, A.; Helou, G.; Dinerstein, H. L.; Hunter, D. A.; Hollenbach, D. J.; Egami, E.; Matthews, K.; Murphy, T. W. Jr;

The First Hundred Brown Dwarfs Discovered by the Wide-Field Infrared Survey Explorer (WISE)

NASA Technical Reports Server (NTRS)

Kirkpatrick, J. Davy; Cushing, Michael C.; Gelino, Christopher R.; Griffith, Roger L.; Skrutskie, Michael F.; Marsh, Kenneth A.; Wright, Edward L.; Mainzer, Amanda K.; Eisenhardt, Peter R.; McLean, Ian S.;

Hubble's Wide View of 'Mystic Mountain' in Infrared

NASA Image and Video Library

2010-04-23

NASA image release April 22, 2010 This is a NASA Hubble Space Telescope near-infrared-light image of a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby stars in the tempestuous stellar nursery called the Carina Nebula, located 7,500 light-years away in the southern constellation Carina. The image marks the 20th anniversary of Hubble's launch and deployment into an orbit around Earth. The image reveals a plethora of stars behind the gaseous veil of the nebula's wall of hydrogen, laced with dust. The foreground pillar becomes semi-transparent because infrared light from background stars penetrates through much of the dust. A few stars inside the pillar also become visible. The false colors are assigned to three different infrared wavelength ranges. Hubble's Wide Field Camera 3 observed the pillar in February and March 2010. Object Names: HH 901, HH 902 Image Type: Astronomical Credit: NASA, ESA, and M. Livio and the Hubble 20th Anniversary Team (STScI) To read learn more about this image go to: www.nasa.gov/mission_pages/hubble/science/hubble20th-img.... NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

Near-infrared spectral image analysis of pork marbling based on Gabor filter and wide line detector techniques.

PubMed

Huang, Hui; Liu, Li; Ngadi, Michael O; Gariépy, Claude; Prasher, Shiv O

2014-01-01

Marbling is an important quality attribute of pork. Detection of pork marbling usually involves subjective scoring, which raises the efficiency costs to the processor. In this study, the ability to predict pork marbling using near-infrared (NIR) hyperspectral imaging (900-1700 nm) and the proper image processing techniques were studied. Near-infrared images were collected from pork after marbling evaluation according to current standard chart from the National Pork Producers Council. Image analysis techniques-Gabor filter, wide line detector, and spectral averaging-were applied to extract texture, line, and spectral features, respectively, from NIR images of pork. Samples were grouped into calibration and validation sets. Wavelength selection was performed on calibration set by stepwise regression procedure. Prediction models of pork marbling scores were built using multiple linear regressions based on derivatives of mean spectra and line features at key wavelengths. The results showed that the derivatives of both texture and spectral features produced good results, with correlation coefficients of validation of 0.90 and 0.86, respectively, using wavelengths of 961, 1186, and 1220 nm. The results revealed the great potential of the Gabor filter for analyzing NIR images of pork for the effective and efficient objective evaluation of pork marbling.

Near-common-path interferometer for imaging Fourier-transform spectroscopy in wide-field microscopy

PubMed Central

Wadduwage, Dushan N.; Singh, Vijay Raj; Choi, Heejin; Yaqoob, Zahid; Heemskerk, Hans; Matsudaira, Paul; So, Peter T. C.

2017-01-01

Imaging Fourier-transform spectroscopy (IFTS) is a powerful method for biological hyperspectral analysis based on various imaging modalities, such as fluorescence or Raman. Since the measurements are taken in the Fourier space of the spectrum, it can also take advantage of compressed sensing strategies. IFTS has been readily implemented in high-throughput, high-content microscope systems based on wide-field imaging modalities. However, there are limitations in existing wide-field IFTS designs. Non-common-path approaches are less phase-stable. Alternatively, designs based on the common-path Sagnac interferometer are stable, but incompatible with high-throughput imaging. They require exhaustive sequential scanning over large interferometric path delays, making compressive strategic data acquisition impossible. In this paper, we present a novel phase-stable, near-common-path interferometer enabling high-throughput hyperspectral imaging based on strategic data acquisition. Our results suggest that this approach can improve throughput over those of many other wide-field spectral techniques by more than an order of magnitude without compromising phase stability. PMID:29392168

A PUBLIC, K-SELECTED, OPTICAL-TO-NEAR-INFRARED CATALOG OF THE EXTENDED CHANDRA DEEP FIELD SOUTH (ECDFS) FROM THE MULTIWAVELENGTH SURVEY BY YALE-CHILE (MUSYC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Edward N.; Franx, Marijn; Quadri, Ryan F.

2009-08-01

We present a new, K-selected, optical-to-near infrared photometric catalog of the Extended Chandra Deep Field South (ECDFS), making it publicly available to the astronomical community.{sup 22}Imaging and spectroscopy data and catalogs are freely available through the MUSYC Public Data Release webpage: http://www.astro.yale.edu/MUSYC/. The data set is founded on publicly available imaging, supplemented by original z'JK imaging data collected as part of the MUltiwavelength Survey by Yale-Chile (MUSYC). The final photometric catalog consists of photometry derived from UU {sub 38} BVRIz'JK imaging covering the full 1/2 x 1/2 square circ of the ECDFS, plus H-band photometry for approximately 80% of themore » field. The 5{sigma} flux limit for point sources is K{sup (AB)}{sub tot}= 22.0. This is also the nominal completeness and reliability limit of the catalog: the empirical completeness for 21.75 < K < 22.00 is {approx}>85%. We have verified the quality of the catalog through both internal consistency checks, and comparisons to other existing and publicly available catalogs. As well as the photometric catalog, we also present catalogs of photometric redshifts and rest-frame photometry derived from the 10-band photometry. We have collected robust spectroscopic redshift determinations from published sources for 1966 galaxies in the catalog. Based on these sources, we have achieved a (1{sigma}) photometric redshift accuracy of {delta}z/(1 + z) = 0.036, with an outlier fraction of 7.8%. Most of these outliers are X-ray sources. Finally, we describe and release a utility for interpolating rest-frame photometry from observed spectral energy distributions, dubbed InterRest.{sup 23}InterRest is available via http://www.strw.leidenuniv.nl/{approx}ent/InterRest. Documentation and a complete walkthrough can be found at the same address.« less

Augmented microscopy: real-time overlay of bright-field and near-infrared fluorescence images

PubMed Central

Watson, Jeffrey R.; Gainer, Christian F.; Martirosyan, Nikolay; Skoch, Jesse; Lemole, G. Michael; Anton, Rein; Romanowski, Marek

2015-01-01

Abstract. Intraoperative applications of near-infrared (NIR) fluorescent contrast agents can be aided by instrumentation capable of merging the view of surgical field with that of NIR fluorescence. We demonstrate augmented microscopy, an intraoperative imaging technique in which bright-field (real) and electronically processed NIR fluorescence (synthetic) images are merged within the optical path of a stereomicroscope. Under luminance of 100,000 lx, representing typical illumination of the surgical field, the augmented microscope detects 189 nM concentration of indocyanine green and produces a composite of the real and synthetic images within the eyepiece of the microscope at 20 fps. Augmentation described here can be implemented as an add-on module to visualize NIR contrast agents, laser beams, or various types of electronic data within the surgical microscopes commonly used in neurosurgical, cerebrovascular, otolaryngological, and ophthalmic procedures. PMID:26440760

Augmented microscopy: real-time overlay of bright-field and near-infrared fluorescence images.

PubMed

Watson, Jeffrey R; Gainer, Christian F; Martirosyan, Nikolay; Skoch, Jesse; Lemole, G Michael; Anton, Rein; Romanowski, Marek

2015-10-01

Intraoperative applications of near-infrared (NIR) fluorescent contrast agents can be aided by instrumentation capable of merging the view of surgical field with that of NIR fluorescence. We demonstrate augmented microscopy, an intraoperative imaging technique in which bright-field (real) and electronically processed NIR fluorescence (synthetic) images are merged within the optical path of a stereomicroscope. Under luminance of 100,000 lx, representing typical illumination of the surgical field, the augmented microscope detects 189 nM concentration of indocyanine green and produces a composite of the real and synthetic images within the eyepiece of the microscope at 20 fps. Augmentation described here can be implemented as an add-on module to visualize NIR contrast agents, laser beams, or various types of electronic data within the surgical microscopes commonly used in neurosurgical, cerebrovascular, otolaryngological, and ophthalmic procedures.

Augmented microscopy: real-time overlay of bright-field and near-infrared fluorescence images

NASA Astrophysics Data System (ADS)

Watson, Jeffrey R.; Gainer, Christian F.; Martirosyan, Nikolay; Skoch, Jesse; Lemole, G. Michael, Jr.; Anton, Rein; Romanowski, Marek

2015-10-01

Intraoperative applications of near-infrared (NIR) fluorescent contrast agents can be aided by instrumentation capable of merging the view of surgical field with that of NIR fluorescence. We demonstrate augmented microscopy, an intraoperative imaging technique in which bright-field (real) and electronically processed NIR fluorescence (synthetic) images are merged within the optical path of a stereomicroscope. Under luminance of 100,000 lx, representing typical illumination of the surgical field, the augmented microscope detects 189 nM concentration of indocyanine green and produces a composite of the real and synthetic images within the eyepiece of the microscope at 20 fps. Augmentation described here can be implemented as an add-on module to visualize NIR contrast agents, laser beams, or various types of electronic data within the surgical microscopes commonly used in neurosurgical, cerebrovascular, otolaryngological, and ophthalmic procedures.

The near-infrared continuum emission of visual reflection nebulae

NASA Technical Reports Server (NTRS)

Sellgren, K.

1984-01-01

In the past, reflection nebulae have provided an astrophysical laboratory well suited for the study of the reflection properties of interstellar dust grains at visual and ultraviolet wavelengths. The present investigation is concerned with observations which were begun with the objective to extend to near-infrared wavelengths the study of grains in reflection. Observations of three classical visual reflection nebulae were conducted in the wavelength range from 1.25 to 2.2 microns, taking into account NGC 7023, 2023, and 2068. All three nebulae were found to have similar near-infrared colors, despite widely different colors of their illuminating stars. The brightness level shown by two of the nebulae at 2.2 microns was too high to be easily accounted for on the basis of reflected light. Attention is given to a wide variety of possible emission mechanisms.

The UKIRT Infrared Deep Sky Survey (UKIDSS)

NASA Astrophysics Data System (ADS)

Lawrence, A.; Warren, S. J.; Almaini, O.; Edge, A. C.; Hambly, N. C.; Jameson, R. F.; Lucas, P.; Casali, M.; Adamson, A.; Dye, S.; Emerson, J. P.; Foucaud, S.; Hewett, P.; Hirst, P.; Hodgkin, S. T.; Irwin, M. J.; Lodieu, N.; McMahon, R. G.; Simpson, C.; Smail, I.; Mortlock, D.; Folger, M.

2007-08-01

We describe the goals, design, implementation, and initial progress of the UKIRT Infrared Deep Sky Survey (UKIDSS), a seven-year sky survey which began in 2005 May. UKIDSS is being carried out using the UKIRT Wide Field Camera (WFCAM), which has the largest étendue of any infrared astronomical instrument to date. It is a portfolio of five survey components covering various combinations of the filter set ZYJHK and H2. The Large Area Survey, the Galactic Clusters Survey, and the Galactic Plane Survey cover approximately 7000deg2 to a depth of K ~ 18; the Deep Extragalactic Survey covers 35deg2 to K ~ 21, and the Ultra Deep Survey covers 0.77deg2 to K ~ 23. Summed together UKIDSS is 12 times larger in effective volume than the 2MASS survey. The prime aim of UKIDSS is to provide a long-term astronomical legacy data base; the design is, however, driven by a series of specific goals - for example, to find the nearest and faintest substellar objects, to discover Population II brown dwarfs, if they exist, to determine the substellar mass function, to break the z = 7 quasar barrier; to determine the epoch of re-ionization, to measure the growth of structure from z = 3 to the present day, to determine the epoch of spheroid formation, and to map the Milky Way through the dust, to several kpc. The survey data are being uniformly processed. Images and catalogues are being made available through a fully queryable user interface - the WFCAM Science Archive (http://surveys.roe.ac.uk/wsa). The data are being released in stages. The data are immediately public to astronomers in all ESO member states, and available to the world after 18 months. Before the formal survey began, UKIRT and the UKIDSS consortia collaborated in obtaining and analysing a series of small science verification (SV) projects to complete the commissioning of the camera. We show some results from these SV projects in order to demonstrate the likely power of the eventual complete survey. Finally, using the data

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

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

Mid-infrared laser phase-locking to a remote near-infrared frequency reference for high-precision molecular spectroscopy

NASA Astrophysics Data System (ADS)

Chanteau, B.; Lopez, O.; Zhang, W.; Nicolodi, D.; Argence, B.; Auguste, F.; Abgrall, M.; Chardonnet, C.; Santarelli, G.; Darquié, B.; Le Coq, Y.; Amy-Klein, A.

2013-07-01

We present a method for accurate mid-infrared frequency measurements and stabilization to a near-infrared ultra-stable frequency reference, transmitted with a long-distance fibre link and continuously monitored against state-of-the-art atomic fountain clocks. As a first application, we measure the frequency of an OsO4 rovibrational molecular line around 10 μm with an uncertainty of 8 × 10-13. We also demonstrate the frequency stabilization of a mid-infrared laser with fractional stability better than 4 × 10-14 at 1 s averaging time and a linewidth below 17 Hz. This new stabilization scheme gives us the ability to transfer frequency stability in the range of 10-15 or even better, currently accessible in the near infrared or in the visible, to mid-infrared lasers in a wide frequency range.

Near Infrared Luminescence Properties of Mn(5+): Ca5(PO4)3F

NASA Technical Reports Server (NTRS)

Davis, Valetta R.; Hoemmerich, Uwe; Loutts, George B.

1997-01-01

We report a spectroscopic investigation of Mn(5+) doped Ca5(PO4)(sub 3)F or FAP. Mn(5+) doped crystals have recently attracted world wide attention for potential solid-state laser applications. Following optical excitation of Mn: FAP with the 600 nm output of a Nd: YAG OPO laser system, we observed a strong near infrared luminescence centered at around 1150 nm. The room temperature luminescence decay time was measured to be approximately 635 microseconds. We attribute the infrared luminescence to the(1)E yields (3)A2 transition of tetrahedrally coordinated Mn5+ ions located in a strong crystal field environment. Absorption, luminescence and lifetime data of Mn: FAP will be presented and discussed.

Absorption and electrochromic modulation of near-infrared light: realized by tungsten suboxide

NASA Astrophysics Data System (ADS)

Li, Guilian; Zhang, Shouhao; Guo, Chongshen; Liu, Shaoqin

2016-05-01

In the present study, needle-like tungsten suboxide W18O49 nanocrystals were fabricated as the optical active substance to realize the aim of optical control of near-infrared light. The W18O49 nanocrystals were selected in this regard due to their unique optical performance. As revealed by the powder absorption result, the needle-like W18O49 nanocrystals show strong and wide photoabsorption in the entire near infrared region of 780-2500 nm, from which thin films with the W18O49 nanocrystal coating thus benefits and can strongly shield off almost all near infrared irradiation, whereas transmitting the majority of visible light. To make it more tunable, the W18O49 nanocrystals were finally assembled onto an ITO glass via the layer-by-layer strategy for later electrochromic investigation. The nanostructured architectures of the W18O49 nanocrystal electrochromic films exhibit high contrast, faster switching response, higher coloration efficiencies (150 cm2 C-1 at 650 nm and 255 cm2 C-1 at 1300 nm), better long-term redox switching stability (reversibility of 98% after 500 cycles) and wide electrochromic spectrum coverage of both the visible and infrared regions.In the present study, needle-like tungsten suboxide W18O49 nanocrystals were fabricated as the optical active substance to realize the aim of optical control of near-infrared light. The W18O49 nanocrystals were selected in this regard due to their unique optical performance. As revealed by the powder absorption result, the needle-like W18O49 nanocrystals show strong and wide photoabsorption in the entire near infrared region of 780-2500 nm, from which thin films with the W18O49 nanocrystal coating thus benefits and can strongly shield off almost all near infrared irradiation, whereas transmitting the majority of visible light. To make it more tunable, the W18O49 nanocrystals were finally assembled onto an ITO glass via the layer-by-layer strategy for later electrochromic investigation. The nanostructured

Near-infrared dental imaging using scanning fiber endoscope

NASA Astrophysics Data System (ADS)

Zhou, Yaxuan; Lee, Robert; Sadr, Alireza; Seibel, Eric J.

2018-02-01

Near-infrared (NIR) wavelength range of 1300-1500nm has the potential to outperform or augment other dental imaging modalities such as fluorescence imaging, owing to its lower scattering coefficient in enamel and trans- parency on stains and non-cariogenic plaque. However, cameras in this wavelength range are bulky and expensive, which lead to difficulties for in-vivo use and commercialization. Thus, we have proposed a new imaging device combining the scanning fiber endoscopy (SFE) and NIR imaging technology. The NIR SFE system has the advantage of miniature size (1.6 mm), flexible shaft, video frame rate (7Hz) and expandable wide field-of-view (60 degrees). Eleven extracted human teeth with or without occlusal caries were scanned by micro-computed X-ray tomography (micro-CT) to obtain 3D micro-CT images, which serve as the standard for comparison. NIR images in reflection mode were then taken on all the occlusal surfaces, using 1310nm super luminescent diode and 1460nm laser diode respectively. Qualitative comparison was performed between near-infrared im- ages and micro-CT images. Enamel demineralization in NIR appeared as areas of increased reflectivity, and distinguished from non-carious staining at the base of occlusal fissures or developmental defects on cusps. This preliminary work presented proof for practicability of combining NIR imaging technology with SFE for reliable and noninvasive dental imaging with miniaturization and low cost.

Computer-aided discovery of debris disk candidates: A case study using the Wide-Field Infrared Survey Explorer (WISE) catalog

NASA Astrophysics Data System (ADS)

Nguyen, T.; Pankratius, V.; Eckman, L.; Seager, S.

2018-04-01

Debris disks around stars other than the Sun have received significant attention in studies of exoplanets, specifically exoplanetary system formation. Since debris disks are major sources of infrared emissions, infrared survey data such as the Wide-Field Infrared Survey (WISE) catalog potentially harbors numerous debris disk candidates. However, it is currently challenging to perform disk candidate searches for over 747 million sources in the WISE catalog due to the high probability of false positives caused by interstellar matter, galaxies, and other background artifacts. Crowdsourcing techniques have thus started to harness citizen scientists for debris disk identification since humans can be easily trained to distinguish between desired artifacts and irrelevant noises. With a limited number of citizen scientists, however, increasing data volumes from large surveys will inevitably lead to analysis bottlenecks. To overcome this scalability problem and push the current limits of automated debris disk candidate identification, we present a novel approach that uses citizen science results as a seed to train machine learning based classification. In this paper, we detail a case study with a computer-aided discovery pipeline demonstrating such feasibility based on WISE catalog data and NASA's Disk Detective project. Our approach of debris disk candidates classification was shown to be robust under a wide range of image quality and features. Our hybrid approach of citizen science with algorithmic scalability can facilitate big data processing for future detections as envisioned in future missions such as the Transiting Exoplanet Survey Satellite (TESS) and the Wide-Field Infrared Survey Telescope (WFIRST).

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.;

An evaluation of the use of near infrared (NIR) spectroscopy to identify water and oil-borne preservatives

Treesearch

Chi-Leung So; Stan T. Lebow; Leslie H. Groom; Todd F. Shupe

2003-01-01

In this research we experimented with a new and rapid way of analyzing wood. Near Infrared (NIR)spectroscopy together with multivariate analysis is becoming a widely used technique in the field of forest products especially for property determination and is already firmly established in the pulp and paper industry. This method is ideal for the chemical analysis of wood...

Near-Infrared Spectroscopy of Henan and Watsonia Family Asteroids

NASA Astrophysics Data System (ADS)

Bus, S. J.; Binzel, R. P.; Sunshine, J.; Burbine, T. H.; McCoy, T. J.

2002-09-01

We present visible and near-infrared spectra for members of both the Henan and Watsonia asteroid families. These two families are known to contain asteroids belonging to the taxonomic L class based on visible wavelength spectroscopy obtained during the second phase of the Small Main-belt Asteroid Spectroscopic Survey (SMASSII, Bus and Binzel 2002, Icarus in press). The L-type asteroids have visible-wavelength spectra similar to those of K-types but with steeper spectral slopes shortward of 0.75 micron, becoming relatively flat longward of 0.75 micron and showing little or no concave curvature related to a 1 micron silicon absorption band. Our current study of the Henan and Watsonia families uses data obtained with SpeX, a medium-resolution near-infrared spectrograph available at the NASA Infrared Telescope Facility (IRTF) on Mauna Kea. When combined with the SMASSII results, we find the near-infrared spectra of these asteroids contains very weak 1 micron bands but have moderately deep 2 micron bands. A possible interpretation of this anomalous spectral signature is the presence of spinel, suggested by Burbine et al. (1992, Meteoritics 27, 424) for the asteroids 387 Aquitania and 980 Anacostia, both likely members of the Watsonia family (Bus 1999, Ph.D. thesis). The work of Burbine et al. made use of combined ECAS and 52-color measurements covering the visible and near-IR wavelengths out to 2.5 microns. We can now use the high signal-to-noise data obtained with SpeX to more fully explore the mineralogy of the taxonomic L class and to search for evidence of mineralogical variations among the Henan and Watsonia asteroid family members.

Deep ultraviolet scanning near-field optical microscopy for the structural analysis of organic and biological materials

NASA Astrophysics Data System (ADS)

Aoki, Hiroyuki; Hamamatsu, Toyohiro; Ito, Shinzaburo

2004-01-01

Scanning near-field optical microscopy (SNOM) using a deep ultraviolet (DUV) light source was developed for in situ imaging of a variety of chemical species without staining. Numerous kinds of chemical species have a carbon-carbon double bond or aromatic group in their chemical structure, which can be excited at the wavelength below 300 nm. In this study, the wavelength range available for SNOM imaging was extended to the DUV region. DUV-SNOM allowed the direct imaging of polymer thin films with high detection sensitivity and spatial resolution of several tens of nanometers. In addition to the polymer materials, we demonstrated the near-field imaging of a cell without using a fluorescence label.

A near-infrared BSA coated DNA-AgNCs for cellular imaging.

PubMed

Mu, Wei-Yu; Yang, Rui; Robertson, Akrofi; Chen, Qiu-Yun

2018-02-01

Near-infrared silver nanoclusters, have potential applications in the field of biosensing and biological imaging. However, less stability of most DNA-AgNCs limits their application. To obtain stable near-infrared fluorescence DNA-AgNCs for biological imaging, a new kind of near-infrared fluorescent DNA-Ag nanoclusters was constructed using the C3A rich aptamer as a synthesis template, GAG as the enhancer. In particular, a new DNA-AgNCs-Trp@BSA was obtained based on the self-assembly of bovine serum albumin (BSA) and tryptophan loaded DNA-AgNCs by hydrophobic interaction. This self-assembly method can be used to stabilize DNAn-Ag (n = 1-3) nanoclusters. Hence, the near-infrared fluorescence DNA-AgNCs-Trp@BSA was applied in cellular imaging of HepG-2 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

High resolution and deep tissue imaging using a near infrared acoustic resolution photoacoustic microscopy

NASA Astrophysics Data System (ADS)

Moothanchery, Mohesh; Sharma, Arunima; Periyasamy, Vijitha; Pramanik, Manojit

2018-02-01

It is always a great challenge for pure optical techniques to maintain good resolution and imaging depth at the same time. Photoacoustic imaging is an emerging technique which can overcome the limitation by pulsed light illumination and acoustic detection. Here, we report a Near Infrared Acoustic-Resolution Photoacoustic Microscopy (NIR-AR-PAM) systm with 30 MHz transducer and 1064 nm illumination which can achieve a lateral resolution of around 88 μm and imaging depth of 9.2 mm. Compared to visible light NIR beam can penetrate deeper in biological tissue due to weaker optical attenuation. In this work, we also demonstrated the in vivo imaging capabilty of NIRARPAM by near infrared detection of SLN with black ink as exogenous photoacoustic contrast agent in a rodent model.

Click beetle luciferase mutant and near infrared naphthyl-luciferins for improved bioluminescence imaging.

PubMed

Hall, Mary P; Woodroofe, Carolyn C; Wood, Monika G; Que, Ivo; Van't Root, Moniek; Ridwan, Yanto; Shi, Ce; Kirkland, Thomas A; Encell, Lance P; Wood, Keith V; Löwik, Clemens; Mezzanotte, Laura

2018-01-09

The sensitivity of bioluminescence imaging in animals is primarily dependent on the amount of photons emitted by the luciferase enzyme at wavelengths greater than 620 nm where tissue penetration is high. This area of work has been dominated by firefly luciferase and its substrate, D-luciferin, due to the system's peak emission (~ 600 nm), high signal to noise ratio, and generally favorable biodistribution of D-luciferin in mice. Here we report on the development of a codon optimized mutant of click beetle red luciferase that produces substantially more light output than firefly luciferase when the two enzymes are compared in transplanted cells within the skin of black fur mice or in deep brain. The mutant enzyme utilizes two new naphthyl-luciferin substrates to produce near infrared emission (730 nm and 743 nm). The stable luminescence signal and near infrared emission enable unprecedented sensitivity and accuracy for performing deep tissue multispectral tomography in mice.

The Coma Cluster Luminosity Function from Ultraviolet to Near-Infrared

NASA Astrophysics Data System (ADS)

Andreon, S.; Cuillandre, J.-C.; Pello, R.

The Coma cluster luminosity function (LF) from ultraviolet (2000 AA ) to the near-infrared (H band) is summarized. In the UV the LF is very steep, much steeper than in the optical. The steep Coma UV LF implies that faint and bright galaxies give similar contributions to the total UV flux and to the total metal production rate. The ComaUV LF is dominated in number and luminosity by blue galaxies, which are often faint in the optical. Therefore the Coma UV LF is dominated by star forming galaxies, not by massive and large galaxies. The optical Coma LF is relatively steep (alpha=-1.4) over the 11 magnitudes sampled, but its slope and shape depend on considered filter and magnitude. We found a clear steeping of the FL going from B to R bands, indicative of the presence of a large number of red dwarfs, as faint as three bright globular clusters. Furthermore, using Hubble Space Telescope images, we discover that blends of globular clusters, not resolved in individual components due to seeing, look like dwarf galaxies when observed from the ground and are numerous and bright. The existence of these fake extended sources increases the steepness of the LF at faint magnitudes, if not deal on. This concern affects previous deep probing of the luminosity function, but not the present work. The near-infrared LF wa s computed on a near-infrared selected sample of galaxies which photometry is complete down to the typical dwarf (M* +5) luminosity. The Coma LF can be described by a Schechter function with intermediate slope (alpha sim-1.3), plus a dip at MH~-22 mag. The shape of the Coma LF in H band is quite similar to th e one found in the B band. The similarity of the LF in the optical and H bands implies that in the central region of Coma there is no new population of galaxies which is too faint to be observed in the optical band (because dust enshrouded, for instance), down to the magnitudes of dwarfs. The exponential cut of the LF at the bright end is in good agreement with

UKIRT's Wide Field Camera and the Detection of 10 MJupiter Objects

NASA Astrophysics Data System (ADS)

WFCAM Team; UKIDSS Team

2004-06-01

In mid-2004 a near-infrared wide field camera will be commissioned on UKIRT. About 40% of all UKIRT time will go into sky surveys and one of these, the Large Area Survey using YJHK filters, will extend the field brown dwarf population to temperatures and masses significantly lower than those of the T dwarf population discovered by the Sloan and 2MASS surveys. The LAS should find objects as cool as 450 K and as low mass as 10 MJupiter at 10 pc. These planetary-mass objects will possibly require a new spectral type designation.

Astronomical near-infrared echelle gratings

NASA Astrophysics Data System (ADS)

Hinkle, Kenneth H.; Joyce, Richard R.; Liang, Ming

2014-07-01

High-resolution near-infrared echelle spectrographs require coarse rulings in order to match the free spectral range to the detector size. Standard near-IR detector arrays typically are 2 K x 2 K or 4 K x 4 K. Detectors of this size combined with resolutions in the range 30000 to 100000 require grating groove spacings in the range 5 to 20 lines/mm. Moderately high blaze angles are desirable to reduce instrument size. Echelle gratings with these characteristics have potential wide application in both ambient temperature and cryogenic astronomical echelle spectrographs. We discuss optical designs for spectrographs employing immersed and reflective echelle gratings. The optical designs set constraints on grating characteristics. We report on market choices for obtaining these gratings and review our experiments with custom diamond turned rulings.

Hubble Space Telescope Medium Deep Survey. 2: Deconvolution of Wide Field Camera field galaxy images in the 13 hour + 43 deg field

NASA Technical Reports Server (NTRS)

Windhorst, R. A.; Schmidtke, P. C.; Pascarelle, S. M.; Gordon, J. M.; Griffiths, R. E.; Ratnatunga, K. U.; Neuschaefer, L. W.; Ellis, R. S.; Gilmore, G.; Glazebrook, K.

1994-01-01

We present isophotal profiles of six faint field galaxies from some of the first deep images taken for the Hubble Space Telescope (HST) Medium Deep Survey (MDS). These have redshifts in the range z = 0.126 to 0.402. The images were taken with the Wide Field Camera (WFC) in `parallel mode' and deconvolved with the Lucy method using as the point-spread function nearby stars in the image stack. The WFC deconvolutions have a dynamic range of 16 to 20 dB (4 to 5 mag) and an effective resolution approximately less than 0.2 sec (FWHM). The multiorbit HST images allow us to trace the morphology, light profiles, and color gradients of faint field galaxies down to V approximately equal to 22 to 23 mag at sub-kpc resolution, since the redshift range covered is z = 0.1 to 0.4. The goals of the MDS are to study the sub-kpc scale morphology, light profiles, and color gradients for a large samole of faint field galaxies down to V approximately equal to 23 mag, and to trace the fraction of early to late-type galaxies as function of cosmic time. In this paper we study the brighter MDS galaxies in the 13 hour + 43 deg MDS field in detail, and investigate to what extent model fits with pure exponential disks or a(exp 1/4) bulges are justified at V approximately less than 22 mag. Four of the six field galaxies have light profiles that indicate (small) inner bulges following r(exp 1/4) laws down to 0.2 sec resolution, plus a dominant surrounding exponential disk with little or no color gradients. Two occur in a group at z = 0.401, two are barred spiral galaxies at z = 0.179 and z = 0.302, and two are rather subluminous (and edge-on) disk galaxies at z = 0.126 and z = 0.179. Our deep MDS images can detect galaxies down to V, I approximately less than 25 to 26 mag, and demonstrate the impressive potential of HST--even with its pre-refurbished optics--to resolve morphological details in galaxies at cosmologically significant distances (v approximately less than 23 mag). Since the median

Near-infrared quantum dots for HER2 localization and imaging of cancer cells.

PubMed

Rizvi, Sarwat B; Rouhi, Sepideh; Taniguchi, Shohei; Yang, Shi Yu; Green, Mark; Keshtgar, Mo; Seifalian, Alexander M

2014-01-01

Quantum dots are fluorescent nanoparticles with unique photophysical properties that allow them to be used as diagnostic, therapeutic, and theranostic agents, particularly in medical and surgical oncology. Near-infrared-emitting quantum dots can be visualized in deep tissues because the biological window is transparent to these wavelengths. Their small sizes and free surface reactive groups that can be conjugated to biomolecules make them ideal probes for in vivo cancer localization, targeted chemotherapy, and image-guided cancer surgery. The human epidermal growth factor receptor 2 gene (HER2/neu) is overexpressed in 25%-30% of breast cancers. The current methods of detection for HER2 status, including immunohistochemistry and fluorescence in situ hybridization, are used ex vivo and cannot be used in vivo. In this paper, we demonstrate the application of near-infrared-emitting quantum dots for HER2 localization in fixed and live cancer cells as a first step prior to their in vivo application. Near-infrared-emitting quantum dots were characterized and their in vitro toxicity was established using three cancer cell lines, ie, HepG2, SK-BR-3 (HER2-overexpressing), and MCF7 (HER2-underexpressing). Mouse antihuman anti-HER2 monoclonal antibody was conjugated to the near-infrared-emitting quantum dots. In vitro toxicity studies showed biocompatibility of SK-BR-3 and MCF7 cell lines with near-infrared-emitting quantum dots at a concentration of 60 μg/mL after one hour and 24 hours of exposure. Near-infrared-emitting quantum dot antiHER2-antibody bioconjugates successfully localized HER2 receptors on SK-BR-3 cells. Near-infrared-emitting quantum dot bioconjugates can be used for rapid localization of HER2 receptors and can potentially be used for targeted therapy as well as image-guided surgery.

The Capodimonte Deep Field

NASA Astrophysics Data System (ADS)

2001-04-01

information possible in selected viewing directions, assuming that what they find there is representative for the Universe as a whole. This is the philosophy behind the so-called "deep-field" projects that subject small areas of the sky to intensive observations with different telescopes and methods. The astronomers determine the properties of the objects seen, as well as their distances and are then able to obtain a map of the space within the corresponding cone-of-view (the "pencil beam"). Recent, successful examples of this technique are the "Hubble Deep Field" (cf. ESO PR Photo 26/98 ) and the "Chandra Deep Field" ( ESO PR 05/01 ). In this context, the Capodimonte Deep Field (OACDF) is a pilot research project, now underway at the Osservatorio Astronomico di Capodimonte (OAC) in Napoli (Italy). It is a multi-colour imaging survey performed with the Wide Field Imager (WFI) , a 67-million pixel (8k x 8k) digital camera that is installed at the 2.2-m MPG/ESO Telescope at ESO's La Silla Observatory in Chile. The scientific goal of the OACDF is to provide an important database for subsequent extragalactic, galactic and planetary studies. It will allow the astronomers at OAC - who are involved in the VLT Survey Telescope (VST) project - to gain insight into the processing (and use) of the large data flow from a camera similar to, but four times smaller than the OmegaCam wide-field camera that will be installed at the VST. The field selection for the OACDF was based on the following criteria: * There must be no stars brighter than about 9th magnitude in the field, in order to avoid saturation of the CCD detector and effects from straylight in the telescope and camera. No Solar System planets should be near the field during the observations; * It must be located far from the Milky Way plane (at high galactic latitude) in order to reduce the number of galactic stars seen in this direction; * It must be located in the southern sky in order to optimize observing conditions (in

ULTRA-DEEP GEMINI NEAR-INFRARED OBSERVATIONS OF THE BULGE GLOBULAR CLUSTER NGC 6624

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saracino, S.; Dalessandro, E.; Ferraro, F. R.

2016-11-20

We used ultra-deep J and K {sub 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 {sub s} , J - K {sub 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 {sub 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 {submore » 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 {sub 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{sub ⊙}, 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.« less

Dynamical origin of near- and below-threshold harmonic generation of Cs in an intense mid-infrared laser field.

PubMed

Li, Peng-Cheng; Sheu, Yae-Lin; Laughlin, Cecil; Chu, Shih-I

2015-05-20

Near- and below-threshold harmonic generation provides a potential approach to generate vacuum-ultraviolet frequency comb. However, the dynamical origin of in these lower harmonics is less understood and largely unexplored. Here we perform an ab initio quantum study of the near- and below-threshold harmonic generation of caesium (Cs) atoms in an intense 3,600-nm mid-infrared laser field. Combining with a synchrosqueezing transform of the quantum time-frequency spectrum and an extended semiclassical analysis, the roles of multiphoton and multiple rescattering trajectories on the near- and below-threshold harmonic generation processes are clarified. We find that the multiphoton-dominated trajectories only involve the electrons scattered off the higher part of the combined atom-field potential followed by the absorption of many photons in near- and below-threshold regime. Furthermore, only the near-resonant below-threshold harmonic is exclusive to exhibit phase locked features. Our results shed light on the dynamic origin of the near- and below-threshold harmonic generation.

High field CdS detector for infrared radiation

NASA Technical Reports Server (NTRS)

Tyagi, R. C.; Boer, K. W.; Hadley, H. C.; Robertson, J. B.

1972-01-01

New and highly sensitive method of detecting infrared irradiation makes possible solid state infrared detector which is more sensitive near room temperature than usual photoconductive low band gap semiconductor devices. Reconfiguration of high field domains in cadmium sulphide crystals provides basis for discovery.

The Mission Operations System for Wide-field Infrared Survey Explorer (WISE)

NASA Technical Reports Server (NTRS)

Heinrichsen, Ingolf H.

2006-01-01

The goal of the Wide-field Infrared Survey Explorer (WISE) mission is to perform a highly sensitive all-sky survey in 4 wavebands from 3 to 25(mu)m. Launched on a Delta II rocket into a 500km Sun-synchronous orbit in June 2009, during its 7 months of operations, WISE will acquire about 50GBytes of raw science data every day, which will be down-linked via the TDRSS relay satellite system and processed into an astronomical catalogue and image atlas. The WISE mission operations system is being implemented in collaboration between UCLA, JPL and IPAC (Caltech). In this paper we describe the challenges to manage a high data rate, cryogenic, low earth-orbit mission; maintaining safe on-orbit operations, fast anomaly recoveries (mandated by the desire to provide complete sky coverage in a limited lifetime), production and dissemination of high quality science products, given the constraints imposed by funding profiles for small space missions.

A New Method for Blood NT-proBNP Determination Based on a Near-infrared Point of Care Testing Device with High Sensitivity and Wide Scope.

PubMed

Zhang, Xiao Guang; Shu, Yao Gen; Gao, Ju; Wang, Xuan; Liu, Li Peng; Wang, Meng; Cao, Yu Xi; Zeng, Yi

2017-06-01

To develop a rapid, highly sensitive, and quantitative method for the detection of NT-proBNP levels based on a near-infrared point-of-care diagnostic (POCT) device with wide scope. The lateral flow assay (LFA) strip of NT-proBNP was first prepared to achieve rapid detection. Then, the antibody pairs for NT-proBNP were screened and labeled with the near-infrared fluorescent dye Dylight-800. The capture antibody was fixed on a nitrocellulose membrane by a scribing device. Serial dilutions of serum samples were prepared using NT-proBNP-free serum series. The prepared test strips, combined with a near-infrared POCT device, were validated by known concentrations of clinical samples. The POCT device gave the output of the ratio of the intensity of the fluorescence signal of the detection line to that of the quality control line. The relationship between the ratio value and the concentration of the specimen was plotted as a work curve. The results of 62 clinical specimens obtained from our method were compared in parallel with those obtained from the Roche E411 kit. Based on the log-log plot, the new method demonstrated that there was a good linear relationship between the ratio value and NT-proBNP concentrations ranging from 20 pg/mL to 10 ng/mL. The results of the 62 clinical specimens measured by our method showed a good linear correlation with those measured by the Roche E411 kit. The new LFA detection method of NT-proBNP levels based on the near-infrared POCT device was rapid and highly sensitive with wide scope and was thus suitable for rapid and early clinical diagnosis of cardiac impairment. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

Food Safety Evaluation Based on Near Infrared Spectroscopy and Imaging: A Review.

PubMed

Fu, Xiaping; Ying, Yibin

2016-08-17

In recent years, due to the increasing consciousness of food safety and human health, much progress has been made in developing rapid and nondestructive techniques for the evaluation of food hazards, food authentication, and traceability. Near infrared (NIR) spectroscopy and imaging techniques have gained wide acceptance in many fields because of their advantages over other analytical techniques. Following a brief introduction of NIR spectroscopy and imaging basics, this review mainly focuses on recent NIR spectroscopy and imaging applications for food safety evaluation, including (1) chemical hazards detection; (2) microbiological hazards detection; (3) physical hazards detection; (4) new technology-induced food safety concerns; and (5) food traceability. The review shows NIR spectroscopy and imaging to be effective tools that will play indispensable roles for food safety evaluation. In addition, on-line/real-time applications of these techniques promise to be a huge growth field in the near future.

Enhanced detection of myeloperoxidase activity in deep tissues through luminescent excitation of near-infrared nanoparticles.

PubMed

Zhang, Ning; Francis, Kevin P; Prakash, Arun; Ansaldi, Daniel

2013-04-01

A previous study reported the use of luminol for the detection of myeloperoxidase (MPO) activity using optical imaging in infiltrating neutrophils under inflammatory disease conditions. The detection is based on a photon-emitting reaction between luminol and an MPO metabolite. Because of tissue absorption and scattering, however, luminol-emitted blue light can be efficiently detected from superficial inflammatory foci only. In this study we report a chemiluminescence resonance energy transfer (CRET) methodology in which luminol-generated blue light excites nanoparticles to emit light in the near-infrared spectral range, resulting in remarkable improvement of MPO detectability in vivo. CRET caused a 37-fold increase in luminescence emission over luminol alone in detecting MPO activity in lung tissues after lipopolysaccharide challenge. We demonstrated a dependence of the chemiluminescent signal on MPO activity using MPO-deficient mice. In addition, co-administration of 4-aminobenzoic acid hydrazide (4-ABAH), an irreversible inhibitor of MPO, significantly attenuated luminescent emission from inflamed lungs. Inhibition of nitric oxide synthase with a nonspecific inhibitor, L-NAME, had no effect on luminol-mediated chemiluminescence production. Pretreatment of mice with MLN120B, a selective inhibitor of IKK-2, resulted in suppression of neutrophil infiltration to the lung tissues and reduction of MPO activity. We also demonstrated that CRET can effectively detect MPO activity at deep tissue tumor foci due to tumor development-associated neutrophil infiltration. We developed a sensitive MPO detection methodology that provides a means for visualizing and quantifying oxidative stress in deep tissue. This method is amenable to rapid evaluation of anti-inflammatory agents in animal models.

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. Published by Elsevier Inc.

AKARI Deep Observations of the Chandra Deep Field South

NASA Astrophysics Data System (ADS)

Burgarella, D.; Buat, V.; Takeuchi, T. T.; Wada, T.; Pearson, C.

2009-12-01

The Chandra Deep Field South is one of the deep fields that has been observed over almost all the electromagnetic spectrum. It contains a wealth of data very useful to study and better understand distant galaxies and their evolution. However, one piece of information was missing in the Mid Infrared and that is why we have obtained 15 μm observations with AKARI/IRC infrared space telescope. From these observations, we have defined a sample of mid infrared-selected galaxies at 15 μm and 15 μm flux densities for a sample of Lyman Break Galaxies at z ˜ 1 already observed at 24 μm with Spitzer/MIPS and identified in the ultraviolet with GALEX. Of the two above samples at z ˜ 1 we have tested the validity of the conversions from luminosities νfν at 8 μm to total dust luminosities by comparing with luminosities estimated from 12 μm data used as a reference. Some calibrations seem better when compared to Ldust evaluated from longer wavelength luminosities. We also have found that the rest-frame 8 μm luminosities provide good estimates of Ldust. By comparing our data to several libraries of spectral energy distributions, we have found that models can explain the diversity of the observed f24 / f15 ratio quite reasonably. Finally, we have revisited the evolution of Ldust / LUV ratio with the redshift z by re-calibrating previous Ldust at z ˜ 2 based on our results and added new data points at higher redshifts. The decreasing trend is amplified as compared to the previous estimate.

Calculating Proper Motions in the WFCAM Science Archive for the UKIRT Infrared Deep Sky Surveys

NASA Astrophysics Data System (ADS)

Collins, R.; Hambly, N.

2012-09-01

The ninth data release from the UKIRT Infrared Deep Sky Surveys (hereafter UKIDSS DR9), represents five years worth of observations by its wide-field camera (WFCAM) and will be the first to include proper motion values in its source catalogues for the shallow, wide-area surveys; the Large Area Survey (LAS), Galactic Clusters Survey (GCS) and (ultimately) Galactic Plane Survey (GPS). We, the Wide Field Astronomy Unit (WFAU) at the University of Edinburgh who prepare these regular data releases in the WFCAM Science Archive (WSA), describe in this paper how we make optimal use of the individual detection catalogues from each observation to derive high-quality astrometric fits for the positions of each detection enabling us to calculate a proper motion solution across multiple epochs and passbands when constructing a merged source catalogue. We also describe how the proper motion solutions affect the calculation of the various attributes provided in the database source catalogue tables, what measures of data quality we provide and a demonstration of the results for observations of the Pleiades cluster.

Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser.

PubMed

Craig, Ian M; Taubman, Matthew S; Lea, A Scott; Phillips, Mark C; Josberger, Erik E; Raschke, Markus B

2013-12-16

Utilizing a broadly-tunable external cavity quantum cascade laser for scattering-type scanning near-field optical microscopy (s-SNOM), we measure infrared spectra of particles of explosives by probing characteristic nitro-group resonances in the 7.1-7.9 µm wavelength range. Measurements are presented with spectral resolution of 0.25 cm(-1), spatial resolution of 25 nm, sensitivity better than 100 attomoles, and at a rapid acquisition time of 90 s per spectrum. We demonstrate high reproducibility of the acquired s-SNOM spectra with very high signal-to-noise ratios and relative noise of <0.02 in self-homodyne detection.

Near-Infrared Fluorescent Materials for Sensing of Biological Targets

PubMed Central

Amiot, Carrie L.; Xu, Shuping; Liang, Song; Pan, Lingyun; Zhao, Julia Xiaojun

2008-01-01

Near-infrared fluorescent (NIRF) materials are promising labeling reagents for sensitive determination and imaging of biological targets. In the near-infrared region biological samples have low background fluorescence signals, providing high signal to noise ratio. Meanwhile, near-infrared radiation can penetrate into sample matrices deeply due to low light scattering. Thus, in vivo and in vitro imaging of biological samples can be achieved by employing the NIRF probes. To take full advantage of NIRF materials in the biological and biomedical field, one of the key issues is to develop intense and biocompatible NIRF probes. In this review, a number of NIRF materials are discussed including traditional NIRF dye molecules, newly developed NIRF quantum dots and single-walled carbon nanotubes, as well as rare earth metal compounds. The use of some NIRF materials in various nanostructures is illustrated. The enhancement of NIRF using metal nanostructures is covered as well. The fluorescence mechanism and bioapplications of each type of the NIRF materials are discussed in details. PMID:27879867

Near-infrared scattering as a dust diagnostic

NASA Astrophysics Data System (ADS)

Saajasto, Mika; Juvela, Mika; Malinen, Johanna

2018-06-01

Context. Regarding the evolution of dust grains from diffuse regions of space to dense molecular cloud cores, many questions remain open. Scattering at near-infrared wavelengths, or "cloudshine", can provide information on cloud structure, dust properties, and the radiation field that is complementary to mid-infrared "coreshine" and observations of dust emission at longer wavelengths. Aims: We examine the possibility of using near-infrared scattering to constrain the local radiation field and the dust properties, the scattering and absorption efficiency, the size distribution of the grains, and the maximum grain size. Methods: We use radiative transfer modelling to examine the constraints provided by the J, H, and K bands in combination with mid-infrared surface brightness at 3.6 μm. We use spherical one-dimensional and elliptical three-dimensional cloud models to study the observable effects of different grain size distributions with varying absorption and scattering properties. As an example, we analyse observations of a molecular cloud in Taurus, TMC-1N. Results: The observed surface brightness ratios of the bands change when the dust properties are changed. However, even a change of ±10% in the surface brightness of one band changes the estimated power-law exponent of the size distribution γ by up to 30% and the estimated strength of the radiation field KISRF by up to 60%. The maximum grain size Amax and γ are always strongly anti-correlated. For example, overestimating the surface brightness by 10% changes the estimated radiation field strength by 20% and the exponent of the size distribution by 15%. The analysis of our synthetic observations indicates that the relative uncertainty of the parameter distributions are on average Amax, γ 25%, and the deviation between the estimated and correct values ΔQ < 15%. For the TMC-1N observations, a maximum grain size Amax > 1.5μm and a size distribution with γ > 4.0 have high probability. The mass weighted

Pulsating stars in ω Centauri. Near-IR properties and period-luminosity relations

NASA Astrophysics Data System (ADS)

Navarrete, Camila; Catelan, Márcio; Contreras Ramos, Rodrigo; Alonso-García, Javier; Gran, Felipe; Dékány, István; Minniti, Dante

2017-09-01

ω Centauri (NGC 5139) contains many variable stars of different types, including the pulsating type II Cepheids, RR Lyrae and SX Phoenicis stars. We carried out a deep, wide-field, near-infrared (IR) variability survey of ω Cen, using the VISTA telescope. We assembled an unprecedented homogeneous and complete J and KS near-IR catalog of variable stars in the field of ω Cen. In this paper we compare optical and near-IR light curves of RR Lyrae stars, emphasizing the main differences. Moreover, we discuss the ability of near-IR observations to detect SX Phoenicis stars given the fact that the amplitudes are much smaller in these bands compared to the optical. Finally, we consider the case in which all the pulsating stars in the three different variability types follow a single period-luminosity relation in the near-IR bands.

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.

Multimode simulations of a wide field of view double-Fourier far-infrared spatio-spectral interferometer

NASA Astrophysics Data System (ADS)

Bracken, Colm P.; Lightfoot, John; O'Sullivan, Creidhe; Murphy, J. Anthony; Donohoe, Anthony; Savini, Giorgio; Juanola-Parramon, Roser; The Fisica Consortium, On Behalf Of

2018-01-01

In the absence of 50-m class space-based observatories, subarcsecond astronomy spanning the full far-infrared wavelength range will require space-based long-baseline interferometry. The long baselines of up to tens of meters are necessary to achieve subarcsecond resolution demanded by science goals. Also, practical observing times command a field of view toward an arcminute (1‧) or so, not achievable with a single on-axis coherent detector. This paper is concerned with an application of an end-to-end instrument simulator PyFIInS, developed as part of the FISICA project under funding from the European Commission's seventh Framework Programme for Research and Technological Development (FP7). Predicted results of wide field of view spatio-spectral interferometry through simulations of a long-baseline, double-Fourier, far-infrared interferometer concept are presented and analyzed. It is shown how such an interferometer, illuminated by a multimode detector can recover a large field of view at subarcsecond angular resolution, resulting in similar image quality as that achieved by illuminating the system with an array of coherent detectors. Through careful analysis, the importance of accounting for the correct number of higher-order optical modes is demonstrated, as well as accounting for both orthogonal polarizations. Given that it is very difficult to manufacture waveguide and feed structures at sub-mm wavelengths, the larger multimode design is recommended over the array of smaller single mode detectors. A brief note is provided in the conclusion of this paper addressing a more elegant solution to modeling far-infrared interferometers, which holds promise for improving the computational efficiency of the simulations presented here.

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.

Development of tapered silver-halide fiber tips for a scanning near-field microscope operating in the middle infrared

NASA Astrophysics Data System (ADS)

Platkov, Max; Tsun, Alexander; Nagli, Lev; Katzir, Abraham

2006-12-01

We have constructed a scanning near-field infrared microscope (SNIM) which was based on a AgClBr fiber probe whose end was etched to form an aperture of a subwavelength diameter. A detailed study of the mechanical properties of a vibrating AgClBr probe was required for proper operation of the SNIM system. We have demonstrated that the system can be used for imaging and for topographic mapping of samples with a subwavelength resolution in the middle infrared. Such a SNIM will be a powerful tool for the study of microelectronic components or subcellular structures in biological cells.

Geological Characterization of Remote Field Sites Using Visible and Infrared Spectroscopy: Results from the 1999 Marsokhod Field Test

NASA Technical Reports Server (NTRS)

Johnson, J. R.; Ruff, S. W.; Moersch, J.; Roush, T.; Horton, K.; Bishop, J.; Cabrol, N. A.; Cockell, C.; Gazis, P.; Newsom, H. E.

2000-01-01

The 1999 Marsokhod Field Experiment (MFE) provided an opportunity to test the suitability of rover-borne visible/near-infrared and thermal infrared field spectrometers to contribute to the remote geological exploration of a Mars analog field site.

Wide-Field InfraRed Survey Telescope (WFIRST) Mission and Synergies with LISA and LIGO-Virgo

NASA Technical Reports Server (NTRS)

Gehrels, N.; Spergel, D.

2015-01-01

The Wide-Field InfraRed Survey Telescope (WFIRST) is a NASA space mission in study for launch in 2024. It has a 2.4 m telescope, wide-field IR instrument operating in the 0.7 - 2.0 micron range and an exoplanet imaging coronagraph instrument operating in the 400 - 1000 nm range. The observatory will perform galaxy surveys over thousands of square degrees to J=27 AB for dark energy weak lensing and baryon acoustic oscillation measurements and will monitor a few square degrees for dark energy SN Ia studies. It will perform microlensing observations of the galactic bulge for an exoplanet census and direct imaging observations of nearby exoplanets with a pathfinder coronagraph. The mission will have a robust and wellfunded guest observer program for 25% of the observing time. WFIRST will be a powerful tool for time domain astronomy and for coordinated observations with gravitational wave experiments. Gravitational wave events produced by mergers of nearby binary neutron stars (LIGO-Virgo) or extragalactic supermassive black hole binaries (LISA) will produce electromagnetic radiation that WFIRST can observe.

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.

Evaluation of blood adsorption onto dialysis membranes by time-of-flight secondary ion mass spectrometry and near-field infrared microscopy.

PubMed

Aoyagi, Satoka; Abe, Kiyoshi; Yamagishi, Takayuki; Iwai, Hideo; Yamaguchi, Satoru; Sunohara, Takashi

2017-11-01

Blood adsorption onto the inside surface of hollow fiber dialysis membranes was investigated by means of time-of-flight secondary ion mass spectrometry (TOF-SIMS) and near-field infrared microscopy (NFIR) in order to evaluate the biocompatibility and permeability of dialysis membranes. TOF-SIMS is useful for the imaging of particular molecules with a high spatial resolution of approximately 100 nm. In contrast, infrared spectra provide quantitative information and NFIR enables analysis with a high spatial resolution of less than 1 μm, which is close to the resolution of TOF-SIMS. A comparison was made of one of the most widely used dialysis membranes made of polysulfone (PSf), that has an asymmetric and inhomogeneous pore structure, and a newly developed asymmetric cellulose triacetate (ATA) membrane that also has an asymmetric pore structure, even though the conventional cellulose triacetate membrane has a symmetric and homogeneous pore structure. As a result, it was demonstrated that blood adsorption on the inside surface of the ATA membrane is more reduced than that on the PSf membrane. Graphical abstract Analysis of blood adsorption on inside surface of hollow fiber membrane.

VizieR Online Data Catalog: z>~5 AGN in Chandra Deep Field-South (Weigel+, 2015)

NASA Astrophysics Data System (ADS)

Weigel, A. K.; Schawinski, K.; Treister, E.; Urry, C. M.; Koss, M.; Trakhtenbrot, B.

2015-09-01

The Chandra 4-Ms source catalogue by Xue et al. (2011, Cat. J/ApJS/195/10) is the starting point of this work. It contains 740 sources and provides counts and observed frame fluxes in the soft (0.5-2keV), hard (2-8keV) and full (0.5-8keV) band. All object IDs used in this work refer to the source numbers listed in the Xue et al. (2011, Cat. J/ApJS/195/10) Chandra 4-Ms catalogue. We make use of Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) data from the Great Observatories Origins Deep Survey South (GOODS-south) in the optical wavelength range. We use catalogues and images for filters F435W (B), F606W (V), F775W (i) and 850LP (z) from the second GOODS/ACS data release (v2.0; Giavalisco et al., 2004, Cat. II/261). We use Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) Wide Field Camera 3 (WFC3)/infrared data from the first data release (DR1, v1.0) for passbands F105W (Y), F125W (J) and F160W (H) (Grogin et al., 2011ApJS..197...35G; Koekemoer et al., 2011ApJS..197...36K). To determine which objects are red, dusty, low-redshift interlopers, we also include the 3.6 and 4.5 micron Spitzer Infrared Array Camera (IRAC) channels. We use SIMPLE image data from the DR1 (van Dokkum et al., 2005, Spitzer Proposal, 2005.20708) and the first version of the extended SIMPLE catalogue by Damen et al. (2011, Cat. J/ApJ/727/1). (6 data files).

Single Pixel Black Phosphorus Photodetector for Near-Infrared Imaging.

PubMed

Miao, Jinshui; Song, Bo; Xu, Zhihao; Cai, Le; Zhang, Suoming; Dong, Lixin; Wang, Chuan

2018-01-01

Infrared imaging systems have wide range of military or civil applications and 2D nanomaterials have recently emerged as potential sensing materials that may outperform conventional ones such as HgCdTe, InGaAs, and InSb. As an example, 2D black phosphorus (BP) thin film has a thickness-dependent direct bandgap with low shot noise and noncryogenic operation for visible to mid-infrared photodetection. In this paper, the use of a single-pixel photodetector made with few-layer BP thin film for near-infrared imaging applications is demonstrated. The imaging is achieved by combining the photodetector with a digital micromirror device to encode and subsequently reconstruct the image based on compressive sensing algorithm. Stationary images of a near-infrared laser spot (λ = 830 nm) with up to 64 × 64 pixels are captured using this single-pixel BP camera with 2000 times of measurements, which is only half of the total number of pixels. The imaging platform demonstrated in this work circumvents the grand challenges of scalable BP material growth for photodetector array fabrication and shows the efficacy of utilizing the outstanding performance of BP photodetector for future high-speed infrared camera applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Near- and far-field investigation of dark and bright higher order resonances in square loop elements at mid-infrared wavelengths.

PubMed

Tucker, Eric; D'Archangel, Jeffrey; Boreman, Glenn

2017-03-06

Three different size gold square loop structures were fabricated as arrays on ZnS over a ground plane and designed to have absorptive fundamental, second order, and third order resonances at a wavelength of 10.6 µm and 60° off-normal. The angular dependent far-field spectral absorptivity was investigated over the mid-infrared for each size loop array. It was found that the second order modes were dark at normal incidence, but became excited at off-normal incidence, which is consistent with previous work for similar geometry structures. Furthermore, near-field measurements and simulations at a wavelength of 10.6 µm and 60° off-normal showed that the second order mode (quadrupolar) of the medium size loop yielded a near-field response similar in magnitude to the fundamental mode (dipolar) of the small size loop, which can be important for sensing related applications where both strong near-field enhancement and more uniform or less localized field is beneficial.

Simulation of the fixed optical path difference of near infrared wind imaging interferometer

NASA Astrophysics Data System (ADS)

Rong, Piao; Zhang, Chunmin; Yan, Tingyu; Liu, Dongdong; Li, Yanfen

2017-02-01

As an important part of the earth, atmosphere plays a vital role in filtering the solar radiation, adjusting the temperature and organizing the water circulation and keeping human survival. The passive atmospheric wind measurement is based on the imaging interferometer technology and Doppler effect of electromagnetic wave. By using the wind imaging interferometer to get four interferograms of airglow emission lines, the atmospheric wind velocity, temperature, pressure and emission rate can be derived. Exploring the multi-functional and integrated innovation of detecting wind temperature, wind velocity and trace gas has become a research focus in the field. In the present paper, the impact factors of the fixed optical path difference(OPD) of near infrared wind imaging interferometer(NIWII) are analyzed and the optimum value of the fixed optical path difference is simulated, yielding the optimal results of the fixed optical path difference is 20 cm in near infrared wave band (the O2(a1Δg) airglow emission at 1.27 microns). This study aims at providing theoretical basis and technical support for the detection of stratosphere near infrared wind field and giving guidance for the design and development of near infrared wind imaging interferometer.

Near-Infrared Polarimetry of the Eagle Nebula (M 16)

NASA Astrophysics Data System (ADS)

Sugitani, Koji; Watanabe, Makoto; Tamura, Motohide; Kandori, Ryo; Hough, James H.; Nishiyama, Shogo; Nakajima, Yasushi; Kusakabe, Nobuhiko; Hashimoto, Jun; Nagayama, Takahiro; Nagashima, Chie; Kato, Daisuke; Fukuda, Naoya

2007-06-01

We carried out deep and wide (˜ 8 × 8) JHKs imaging polarimetry in the southern region of the Eagle Nebula (M 16). The polarization intensity map reveals that two YSOs with near-IR reflection nebulae are located at the tips of two famous molecular pillars (Pillars 1 and 2) facing toward the exciting stars of M 16. The centrosymmetric polarization pattern are consistent with those around Class I objects having circumstellar envelopes, confirming that star formation is now taking place at the two tips of the pillars under the influence of UV radiation from the exciting stars. Polarization measurements of point sources show that magnetic fields are aligned along some of the pillars, but in a direction that is quite different to the global structure in M 16.

The SCUBA HAlf Degree Extragalactic Survey (SHADES) - V. Submillimetre properties of near-infrared-selected galaxies in the Subaru/XMM -Newton deep field

NASA Astrophysics Data System (ADS)

Takagi, T.; Mortier, A. M. J.; Shimasaku, K.; Coppin, K.; Pope, A.; Ivison, R. J.; Hanami, H.; Serjeant, S.; Clements, D. L.; Priddey, R. S.; Dunlop, J. S.; Takata, T.; Aretxaga, I.; Chapman, S. C.; Eales, S. A.; Farrah, D.; Granato, G. L.; Halpern, M.; Hughes, D. H.; van Kampen, E.; Scott, D.; Sekiguchi, K.; Smail, I.; Vaccari, M.

2007-11-01

We have studied the submillimetre (submm) properties of the following classes of near-infrared-selected (NIR-selected) massive galaxies at high redshifts: BzK-selected star-forming galaxies (BzKs); distant red galaxies (DRGs); and extremely red objects (EROs). We used the SCUBA HAlf Degree Extragalactic Survey (SHADES), the largest uniform submm survey to date. Partial overlap of SIRIUS/NIR images and SHADES in Subaru/XMM-Newton deep field has allowed us to identify four submm-bright NIR-selected galaxies, which are detected in the mid-IR, 24μ m, and the radio, 1.4GHz. We find that all of our submm-bright NIR-selected galaxies satisfy the BzK selection criteria, i.e. BzK ≡ (z - K)AB - (B - z)AB >= -0.2, except for one galaxy whose B - z and z - K colours are however close to the BzK colour boundary. Two of the submm-bright NIR-selected galaxies satisfy all of the selection criteria we considered, i.e. they belong to the BzK-DRG-ERO overlapping population, or `extremely red' BzKs. Although these extremely red BzKs are rare (0.25 arcmin-2), up to 20 per cent of this population could be submm galaxies. This fraction is significantly higher than that found for other galaxy populations studied here. Via a stacking analysis, we have detected the 850-μ m flux of submm-faint BzKs and EROs in our SCUBA maps. While the contribution of z ~ 2 BzKs to the submm background is about 10-15 per cent and similar to that from EROs typically at z ~ 1, BzKs have a higher fraction (~30 per cent) of submm flux in resolved sources compared with EROs and submm sources as a whole. From the spectral energy distribution (SED) fitting analysis for both submm-bright and submm-faint BzKs, we found no clear signature that submm-bright BzKs are experiencing a specifically luminous evolutionary phase, compared with submm-faint BzKs. An alternative explanation might be that submm-bright BzKs are more massive than submm-faint ones.

Near-Infrared Coloring via a Contrast-Preserving Mapping Model.

PubMed

Chang-Hwan Son; Xiao-Ping Zhang

2017-11-01

Near-infrared gray images captured along with corresponding visible color images have recently proven useful for image restoration and classification. This paper introduces a new coloring method to add colors to near-infrared gray images based on a contrast-preserving mapping model. A naive coloring method directly adds the colors from the visible color image to the near-infrared gray image. However, this method results in an unrealistic image because of the discrepancies in the brightness and image structure between the captured near-infrared gray image and the visible color image. To solve the discrepancy problem, first, we present a new contrast-preserving mapping model to create a new near-infrared gray image with a similar appearance in the luminance plane to the visible color image, while preserving the contrast and details of the captured near-infrared gray image. Then, we develop a method to derive realistic colors that can be added to the newly created near-infrared gray image based on the proposed contrast-preserving mapping model. Experimental results show that the proposed new method not only preserves the local contrast and details of the captured near-infrared gray image, but also transfers the realistic colors from the visible color image to the newly created near-infrared gray image. It is also shown that the proposed near-infrared coloring can be used effectively for noise and haze removal, as well as local contrast enhancement.

Near infrared detection of ammonium minerals.

USGS Publications Warehouse

Krohn, M.D.; Altaner, S.P.

1987-01-01

Diagnostic near-infrared spectral features have been identified for minerals with ammonium (NH4+) bound in the crystal structure. Near-infrared detection of NH4-bearing minerals may provide useful information for prospecting for certain ore deposits and may provide a better understanding of the nitrogen cycle within geologic environments.-from Authors

A widely tunable, near-infrared laser-based trace gas sensor for hydrogen cyanide (HCN) detection in exhaled breath

NASA Astrophysics Data System (ADS)

Azhar, M.; Mandon, J.; Neerincx, A. H.; Liu, Z.; Mink, J.; Merkus, P. J. F. M.; Cristescu, S. M.; Harren, F. J. M.

2017-11-01

A compact, cost-effective sensor is developed for detection of hydrogen cyanide (HCN) in exhaled breath within seconds. For this, an off-axis integrated cavity output spectroscopy setup is combined with a widely tunable compact near-infrared laser (tunability 1527-1564 nm). For HCN a detection sensitivity has been obtained of 8 ppbv in nitrogen (within 1 s), equal to a noise equivalent absorption sensitivity of 1.9 × 10-9 cm-1 Hz-1/2. With this sensor we demonstrated the presence of HCN in exhaled breath; its detection could be a good indicator for bacterial lung infection. Due to its compact, cost-effective and user-friendly design, this laser-based sensor has the potential to be implemented in future clinical applications.

Accuracy of deep learning, a machine-learning technology, using ultra-wide-field fundus ophthalmoscopy for detecting rhegmatogenous retinal detachment.

PubMed

Ohsugi, Hideharu; Tabuchi, Hitoshi; Enno, Hiroki; Ishitobi, Naofumi

2017-08-25

Rhegmatogenous retinal detachment (RRD) is a serious condition that can lead to blindness; however, it is highly treatable with timely and appropriate treatment. Thus, early diagnosis and treatment of RRD is crucial. In this study, we applied deep learning, a machine-learning technology, to detect RRD using ultra-wide-field fundus images and investigated its performance. In total, 411 images (329 for training and 82 for grading) from 407 RRD patients and 420 images (336 for training and 84 for grading) from 238 non-RRD patients were used in this study. The deep learning model demonstrated a high sensitivity of 97.6% [95% confidence interval (CI), 94.2-100%] and a high specificity of 96.5% (95% CI, 90.2-100%), and the area under the curve was 0.988 (95% CI, 0.981-0.995). This model can improve medical care in remote areas where eye clinics are not available by using ultra-wide-field fundus ophthalmoscopy for the accurate diagnosis of RRD. Early diagnosis of RRD can prevent blindness.

Deep infrared galaxies

NASA Technical Reports Server (NTRS)

Ashby, Matthew; Houck, J. R.; Hacking, Perry B.

1992-01-01

High signal-to-noise ratio optical spectra of 17 infrared-bright emission-line galaxies near the north ecliptic pole are presented. Reddening-corrected line ratios forbidden O III 5007/H-beta, N II 6583/H-alpha, S II (6716 + 6731)/H-alpha, and O I 6300/H-alpha are used to discriminate between candidate energy generation mechanisms in each galaxy. These criteria have frequently been applied to optically selected samples of galaxies in the past, but this is the first time they have been applied to a set of faint flux-limited infrared-selected objects. The analysis indicates the sample contains seven starburst galaxies and three (AGN). However, seven galaxies in the present sample elude the classification scheme based on these line ratios. It is concluded that a two-component (starburst plus AGN) model for energy generation is inadequate for infrared galaxies.

Magnetotelluric images of deep crustal structure of the Rehai geothermal field near Tengchong, southern China

NASA Astrophysics Data System (ADS)

Bai, Denghai; Meju, Maxwell A.; Liao, Zhijie

2001-12-01

Broadband (0.004-4096s) magnetotelluric (MT) soundings have been applied to the determination of the deep structure across the Rehai geothermal field in a Quaternary volcanic area near the Indo-Eurasian collisional margin. Tensorial analysis of the data show evidence of weak to strong 3-D effects but for approximate 2-D imaging, we obtained dual-mode MT responses for an assumed strike direction coincident with the trend of the regional-scale faults and with the principal impedance azimuth at long periods. The data were subsequently inverted using different approaches. The rapid relaxation inversion models are comparable to the sections constructed from depth-converted invariant impedance phase data. The results from full-domain 2-D conjugate-gradient inversion with different initial models are concordant and evoke a picture of a dome-like structure consisting of a conductive (<10 Ωm) core zone, c . 2km wide, and a resistive (>50-1000 Ωm) cap which is about 5-6km thick in the central part of the known geothermal field and thickens outwards to about 15-20km. The anomalous structure rests on a mid-crustal zone of 20-30 Ωm resistivity extending down to about 25km depth where there appears to be a moderately resistive (>30 Ωm) substratum. The MT images are shown to be in accord with published geological, isotopic and geochemical results that suggested the presence of a magma body underneath the area of study.

The Wide-Field Infrared Survey Explorer (WISE): Mission Description and Initial On-Orbit Performance

NASA Technical Reports Server (NTRS)

Wright, Edward L.; Eisenhardt, Peter R. M.; Mainzer, Amy; Ressler, Michael E.; Cutri, Roc M.; Jarrett, Thomas; Kirkpatrick, J. Davy; Padgett, Deborah; McMillan, Robert S.; Skrutskie,Michael;

Wide-Field Infrared Survey Explorer Observations of the Evolution of Massive Star-Forming Regions

NASA Technical Reports Server (NTRS)

Koenig, X. P.; Leisawitz, D. T.; Benford, D. J.; Rebull, L. M.; Padgett, D. L.; Assef, R. J.

2011-01-01

We present the results of a mid-infrared survey of 11 outer Galaxy massive star-forming regions and 3 open clusters with data from the Wide-field Infrared Survey Explorer (WISE). Using a newly developed photometric scheme to identify young stellar objects and exclude extragalactic contamination, we have studied the distribution of young stars within each region. These data tend to support the hypothesis that latter generations may be triggered by the interaction of winds and radiation from the first burst of massive star formation with the molecular cloud material leftover from that earlier generation of stars.We dub this process the "fireworks hypothesis" since star formation by this mechanism would proceed rapidly and resemble a burst of fireworks.We have also analyzed small cutout WISE images of the structures around the edges of these massive star-forming regions. We observe large (1-3 pc size) pillar and trunk-like structures of diffuse emission nebulosity tracing excited polycyclic aromatic hydrocarbon molecules and small dust grains at the perimeter of the massive star-forming regions. These structures contain small clusters of emerging Class I and Class II sources, but some are forming only a single to a few new stars.

Wide-Field Infrared Survey Explorer Observations of the Evolution of Massive Star-Forming Regions

NASA Technical Reports Server (NTRS)

Koenig, X. P.; Leisawitz, D. T.; Benford, D. J.; Rebull, L. M.; Padgett, D. L.; Asslef, R. J.

2012-01-01

We present the results of a mid-infrared survey of II outer Galaxy massive star-forming regions and 3 open clusters with data from the Wide-field Infrared Survey Explorer (WISE). Using a newly developed photometric scheme to identify young stellar objects and exclude extragalactic contamination, we have studied the distribution of young stars within each region. These data tend to support the hypothesis that latter generations may be triggered by the interaction of winds and radiation from the first burst of massive star formation with the molecular cloud material leftover from that earlier generation of stars. We dub this process the "fireworks hypothesis" since star formation by this mechanism would proceed rapidly and resemble a burst of fireworks. We have also analyzed small cutout WISE images of the structures around the edges of these massive star-forming regions. We observe large (1-3 pc size) pillar and trunk-like structures of diffuse emission nebulosity tracing excited polycyclic aromatic hydrocarbon molecules and small dust grains at the perimeter of the massive star-forming regions. These structures contain small clusters of emerging Class I and Class II sources, but some are forming only a single to a few new stars.

Voxel-based measurement sensitivity of spatially resolved near-infrared spectroscopy in layered tissues

NASA Astrophysics Data System (ADS)

Niwayama, Masatsugu

2018-03-01

We quantitatively investigated the measurement sensitivity of spatially resolved spectroscopy (SRS) across six tissue models: cerebral tissue, a small animal brain, the forehead of a fetus, an adult brain, forearm muscle, and thigh muscle. The optical path length in the voxel of the model was analyzed using Monte Carlo simulations. It was found that the measurement sensitivity can be represented as the product of the change in the absorption coefficient and the difference in optical path length in two states with different source-detector distances. The results clarified the sensitivity ratio between the surface layer and the deep layer at each source-detector distance for each model and identified changes in the deep measurement area when one of the detectors was close to the light source. A comparison was made with the results from continuous-wave spectroscopy. The study also identified measurement challenges that arise when the surface layer is inhomogeneous. Findings on the measurement sensitivity of SRS at each voxel and in each layer can support the correct interpretation of measured values when near-infrared oximetry or functional near-infrared spectroscopy is used to investigate different tissue structures.

Status and performance of HST/Wide Field Camera 3

NASA Astrophysics Data System (ADS)

Kimble, Randy A.; MacKenty, John W.; O'Connell, Robert W.

2006-06-01

Wide Field Camera 3 (WFC3) is a powerful UV/visible/near-infrared camera currently in development for installation into the Hubble Space Telescope. WFC3 provides two imaging channels. The UVIS channel features a 4096 x 4096 pixel CCD focal plane covering 200 to 1000 nm wavelengths with a 160 x 160 arcsec field of view. The UVIS channel provides unprecedented sensitivity and field of view in the near ultraviolet for HST. It is particularly well suited for studies of the star formation history of local galaxies and clusters, searches for Lyman alpha dropouts at moderate redshift, and searches for low surface brightness structures against the dark UV sky background. The IR channel features a 1024 x 1024 pixel HgCdTe focal plane covering 800 to 1700 nm with a 139 x 123 arcsec field of view, providing a major advance in IR survey efficiency for HST. IR channel science goals include studies of dark energy, galaxy formation at high redshift, and star formation. The instrument is being prepared for launch as part of HST Servicing Mission 4, tentatively scheduled for late 2007, contingent upon formal approval of shuttle-based servicing after successful shuttle return-to-flight. We report here on the status and performance of WFC3.

Deep Reconditioning Testing for near Earth Orbits

NASA Technical Reports Server (NTRS)

Betz, F. E.; Barnes, W. L.

1984-01-01

The problems and benefits of deep reconditioning to near Earth orbit missions with high cycle life and shallow discharge depth requirements is discussed. A simple battery level approach to deep reconditioning of nickel cadmium batteries in near Earth orbit is considered. A test plan was developed to perform deep reconditioning in direct comparison with an alternative trickle charge approach. The results demonstrate that the deep reconditioning procedure described for near Earth orbit application is inferior to the alternative of trickle charging.

Hyper Suprime-Camera Survey of the Akari NEP Wide Field

NASA Astrophysics Data System (ADS)

Goto, Tomotsugu; Toba, Yoshiki; Utsumi, Yousuke; Oi, Nagisa; Takagi, Toshinobu; Malkan, Matt; Ohayma, Youichi; Murata, Kazumi; Price, Paul; Karouzos, Marios; Matsuhara, Hideo; Nakagawa, Takao; Wada, Takehiko; Serjeant, Steve; Burgarella, Denis; Buat, Veronique; Takada, Masahiro; Miyazaki, Satoshi; Oguri, Masamune; Miyaji, Takamitsu; Oyabu, Shinki; White, Glenn; Takeuchi, Tsutomu; Inami, Hanae; Perason, Chris; Malek, Katarzyna; Marchetti, Lucia; Lee, Hyung Mok; Im, Myung; Kim, Seong Jin; Koptelova, Ekaterina; Chao, Dani; Wu, Yi-Han; AKARI NEP Survey Team; AKARI All Sky Survey Team

2017-03-01

The extragalactic background suggests half the energy generated by stars was reprocessed into the infrared (IR) by dust. At z ∼1.3, 90% of star formation is obscured by dust. To fully understand the cosmic star formation history, it is critical to investigate infrared emission. AKARI has made deep mid-IR observation using its continuous 9-band filters in the NEP field (5.4 deg^2), using ∼10% of the entire pointed observations available throughout its lifetime. However, there remain 11,000 AKARI infrared sources undetected with the previous CFHT/Megacam imaging (r ∼25.9ABmag). Redshift and IR luminosity of these sources are unknown. These sources may contribute significantly to the cosmic star-formation rate density (CSFRD). For example, if they all lie at 1 < z < 2, the CSFRD will be twice as high at the epoch. We are carrying out deep imaging of the NEP field in 5 broad bands (g,r,i,z, and y) using Hyper Suprime-Camera (HSC), which has 1.5 deg field of view in diameter on Subaru 8m telescope. This will provide photometric redshift information, and thereby IR luminosity for the previously-undetected 11,000 faint AKARI IR sources. Combined with AKARI's mid-IR AGN/SF diagnosis, and accurate mid-IR luminosity measurement, this will allow a complete census of cosmic star-formation/AGN accretion history obscured by dust.

Vibrational near-field mapping of planar and buried three-dimensional plasmonic nanostructures

PubMed Central

Dregely, Daniel; Neubrech, Frank; Duan, Huigao; Vogelgesang, Ralf; Giessen, Harald

2013-01-01

Nanoantennas confine electromagnetic fields at visible and infrared wavelengths to volumes of only a few cubic nanometres. Assessing their near-field distribution offers fundamental insight into light–matter coupling and is of special interest for applications such as radiation engineering, attomolar sensing and nonlinear optics. Most experimental approaches to measure near-fields employ either diffraction-limited far-field methods or intricate near-field scanning techniques. Here, using diffraction-unlimited far-field spectroscopy in the infrared, we directly map the intensity of the electric field close to plasmonic nanoantennas. We place a patch of probe molecules with 10 nm accuracy at different locations in the near-field of a resonant antenna and extract the molecular vibrational excitation. We map the field intensity along a dipole antenna and gap-type antennas. Moreover, this method is able to assess the near-field intensity of complex buried plasmonic structures. We demonstrate this by measuring for the first time the near-field intensity of a three-dimensional plasmonic electromagnetically induced transparency structure. PMID:23892519

Near-infrared integral field spectroscopy of massive young stellar objects

NASA Astrophysics Data System (ADS)

Murakawa, K.; Lumsden, S. L.; Oudmaijer, R. D.; Davies, B.; Wheelwright, H. E.; Hoare, M. G.; Ilee, J. D.

2013-11-01

We present medium-resolution (R ≈ 5300) K-band integral field spectroscopy of six massive young stellar objects (MYSOs). The targets are selected from the Red MSX Source (RMS) survey, and we used the ALTAIR adaptive optics assisted Near-Infrared Integral Field Spectrometer (NIFS) mounted on the Gemini North telescope. The data show various spectral line features including Brγ, CO, H2 and He I. The Brγ line is detected in emission in all objects with vFWHM ˜ 100-200 km s-1. V645 Cyg shows a high-velocity P-Cygni profile between -800 and -300 km s-1. We performed three-dimensional spectroastrometry to diagnose the circumstellar environment in the vicinity of the central stars using the Brγ line. We measured the centroids of the velocity components with sub-mas precision. The centroids allow us to discriminate the blueshifted and redshifted components in a roughly east-west direction in both IRAS 18151-1208 and S106 in Brγ. This lies almost perpendicular to observed larger scale outflows. We conclude, given the widths of the lines and the orientation of the spectroastrometric signature, that our results trace a disc wind in both IRAS 18151-1208 and S106. The CO ν = 2-0 absorption lines at low J transitions are detected in IRAS 18151-1208 and AFGL 2136. We analysed the velocity structure of the neutral gas discs, which we find to have nearly Keplerian motions. In IRAS 18151-1208, the absorption centroids of the blueshifted and redshifted components are separated in a direction of north-east to south-west, nearly perpendicular to that of the larger scale H2 jet. The position-velocity relations of these objects can be reproduced with central masses of 30 M⊙ for IRAS 18151-1208 and 20 M⊙ for AFGL 2136. We also detect CO ν = 2-0 bandhead emission in IRAS 18151-1208, S106 and V645 Cyg. The results can be fitted reasonably with a Keplerian rotation model, with masses of 15, 20 and 20 M⊙, respectively. These results for a sample of MYSOs can be explained with

Towards a low-cost mobile subcutaneous vein detection solution using near-infrared spectroscopy.

PubMed

Juric, Simon; Flis, Vojko; Debevc, Matjaz; Holzinger, Andreas; Zalik, Borut

2014-01-01

Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature). The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database) the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction.

Towards a Low-Cost Mobile Subcutaneous Vein Detection Solution Using Near-Infrared Spectroscopy

PubMed Central

Flis, Vojko; Debevc, Matjaz; Holzinger, Andreas; Zalik, Borut

2014-01-01

Excessive venipunctures are both time- and resource-consuming events, which cause anxiety, pain, and distress in patients, or can lead to severe harmful injuries. We propose a low-cost mobile health solution for subcutaneous vein detection using near-infrared spectroscopy, along with an assessment of the current state of the art in this field. The first objective of this study was to get a deeper overview of the research topic, through the initial team discussions and a detailed literature review (using both academic and grey literature). The second objective, that is, identifying the commercial systems employing near-infrared spectroscopy, was conducted using the PubMed database. The goal of the third objective was to identify and evaluate (using the IEEE Xplore database) the research efforts in the field of low-cost near-infrared imaging in general, as a basis for the conceptual model of the upcoming prototype. Although the reviewed commercial devices have demonstrated usefulness and value for peripheral veins visualization, other evaluated clinical outcomes are less conclusive. Previous studies regarding low-cost near-infrared systems demonstrated the general feasibility of developing cost-effective vein detection systems; however, their limitations are restricting their applicability to clinical practice. Finally, based on the current findings, we outline the future research direction. PMID:24883388

Novel fast catadioptric objective with wide field of view

NASA Astrophysics Data System (ADS)

Muñoz, Fernando; Infante Herrero, José M.; Benítez, Pablo; Miñano, Juan C.; Lin, Wang; Vilaplana, Juan; Biot, Guillermo; de la Fuente, Marta

2010-08-01

Using the Simultaneous Multiple Surface method in 2D (SMS2D), we present a fast catadioptric objective with a wide field of view (125°×96°) designed for a microbolometer detector with 640×480 pixels and 25 microns pixel pitch Keywords: Infrared lens design, thermal imaging, Schwarzschild configuration, SMS2D, wide field of view, driving cameras, panoramic systems

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.

Optical Design of the WFIRST Phase-A Wide Field Instrument

NASA Technical Reports Server (NTRS)

Pasquale, Bert A.; Marx, Catherine T.; Gao, Guangjun; Armani, Nerses; Casey, Thomas

2017-01-01

The WFIRST Wide-Field Infrared Survey Telescope TMA optical design provides 0.28-sq degrees FOV at 0.11” pixel scale to the Wide Field Instrument, operating between 0.48-2.0 micrometers, including a spectrograph mode (1.0-2.0 micrometers). An Integral Field Channel provides 2-D discrete spectroscopy at 0.15” & 0.3” sampling.

An optical design of the wide-field imaging and multi-object spectrograph for an Antarctic infrared telescope

NASA Astrophysics Data System (ADS)

Ichikawa, Takashi; Obata, Tomokazu

2016-08-01

A design of the wide-field infrared camera (AIRC) for Antarctic 2.5m infrared telescope (AIRT) is presented. The off-axis design provides a 7'.5 ×7'. 5 field of view with 0".22 pixel-1 in the wavelength range of 1 to 5 μm for the simultaneous three-color bands using cooled optics and three 2048×2048 InSb focal plane arrays. Good image quality is obtained over the entire field of view with practically no chromatic aberration. The image size corresponds to the refraction limited for 2.5 m telescope at 2 μm and longer. To enjoy the stable atmosphere with extremely low perceptible water vapor (PWV), superb seeing quality, and the cadence of the polar winter at Dome Fuji on the Antarctic plateau, the camera will be dedicated to the transit observations of exoplanets. The function of a multi-object spectroscopic mode with low spectra resolution (R 50-100) will be added for the spectroscopic transit observation at 1-5 μm. The spectroscopic capability in the environment of extremely low PWV of Antarctica will be very effective for the study of the existence of water vapor in the atmosphere of super earths.

Tunable long persistent luminescence in the second near-infrared window via crystal field control.

PubMed

Nie, Jianmin; Li, Yang; Liu, Shanshan; Chen, Qiuqun; Xu, Qi; Qiu, Jianrong

2017-09-29

Construction of an active composite as a biomarker with deeper tissue penetration and higher signal-to-noise ratio (SNR) is of great importance for the application in bioimaging. Here, we report a strategy for tuning the emission bandwidth and intensity via crystal field control in long persistent phosphors (LPPs). Ni 2+ -doped Zn 1+y Sn y Ga 2-x-2y O 4 phosphors, with a tunable emission band peaking from 1270 to 1430 nm in the second near-infrared (NIR) window, have been successfully prepared. Such featured materials have the advantages of low absorption and scattering as well as more efficient tissue penetration. The emission spectra can be controlled by tailoring the local crystal field around the activator precisely via substitution of Zn and Sn for Ga. Moreover, with high resolution and weak light disturbance, these developed multi-band afterglow phosphors exhibit great application potential in advanced optical imaging.

Empirical calibration of the near-infrared Ca II triplet - III. Fitting functions

NASA Astrophysics Data System (ADS)

Cenarro, A. J.; Gorgas, J.; Cardiel, N.; Vazdekis, A.; Peletier, R. F.

2002-02-01

Using a near-infrared stellar library of 706 stars with a wide coverage of atmospheric parameters, we study the behaviour of the CaII triplet strength in terms of effective temperature, surface gravity and metallicity. Empirical fitting functions for recently defined line-strength indices, namely CaT*, CaT and PaT, are provided. These functions can be easily implemented into stellar population models to provide accurate predictions for integrated CaII strengths. We also present a thorough study of the various error sources and their relation to the residuals of the derived fitting functions. Finally, the derived functional forms and the behaviour of the predicted CaII are compared with those of previous works in the field.

Optical Design of WFIRST-AFTA Wide-Field Instrument

NASA Technical Reports Server (NTRS)

Pasquale, Bert; Content, Dave; Kruk, Jeffrey; Vaughn, David; Gong, Qian; Howard, Joseph; Jurling, Alden; Mentzell, Eric; Armani, Nerses; Kuan, Gary

2014-01-01

The WFIRSTAFTA Wide-Field Infrared Survey Telescope TMA optical design provides 0.28-sq FOV at 0.11 pixel scale, operating between 0.6 2.4m, including a spectrograph mode (1.3-1.95m.) An IFU provides a discrete 3x3.15 field at 0.15 sampling.

Near infrared and visible face recognition based on decision fusion of LBP and DCT features

NASA Astrophysics Data System (ADS)

Xie, Zhihua; Zhang, Shuai; Liu, Guodong; Xiong, Jinquan

2018-03-01

Visible face recognition systems, being vulnerable to illumination, expression, and pose, can not achieve robust performance in unconstrained situations. Meanwhile, near infrared face images, being light- independent, can avoid or limit the drawbacks of face recognition in visible light, but its main challenges are low resolution and signal noise ratio (SNR). Therefore, near infrared and visible fusion face recognition has become an important direction in the field of unconstrained face recognition research. In order to extract the discriminative complementary features between near infrared and visible images, in this paper, we proposed a novel near infrared and visible face fusion recognition algorithm based on DCT and LBP features. Firstly, the effective features in near-infrared face image are extracted by the low frequency part of DCT coefficients and the partition histograms of LBP operator. Secondly, the LBP features of visible-light face image are extracted to compensate for the lacking detail features of the near-infrared face image. Then, the LBP features of visible-light face image, the DCT and LBP features of near-infrared face image are sent to each classifier for labeling. Finally, decision level fusion strategy is used to obtain the final recognition result. The visible and near infrared face recognition is tested on HITSZ Lab2 visible and near infrared face database. The experiment results show that the proposed method extracts the complementary features of near-infrared and visible face images and improves the robustness of unconstrained face recognition. Especially for the circumstance of small training samples, the recognition rate of proposed method can reach 96.13%, which has improved significantly than 92.75 % of the method based on statistical feature fusion.

VICS82: The VISTA–CFHT Stripe 82 Near-infrared Survey

NASA Astrophysics Data System (ADS)

Geach, J. E.; Lin, Y.-T.; Makler, M.; Kneib, J.-P.; Ross, N. P.; Wang, W.-H.; Hsieh, B.-C.; Leauthaud, A.; Bundy, K.; McCracken, H. J.; Comparat, J.; Caminha, G. B.; Hudelot, P.; Lin, L.; Van Waerbeke, L.; Pereira, M. E. S.; Mast, D.

2017-07-01

We present the VISTA–CFHT Stripe 82 (VICS82) survey: a near-infrared (J+Ks) survey covering 150 square degrees of the Sloan Digital Sky Survey (SDSS) equatorial Stripe 82 to an average depth of J = 21.9 AB mag and Ks = 21.4 AB mag (80% completeness limits; 5σ point-source depths are approximately 0.5 mag brighter). VICS82 contributes to the growing legacy of multiwavelength data in the Stripe 82 footprint. The addition of near-infrared photometry to the existing SDSS Stripe 82 coadd ugriz photometry reduces the scatter in stellar mass estimates to δ {log}({M}\\star )≈ 0.3 dex for galaxies with {M}\\star > {10}9 {M}ȯ at z≈ 0.5, and offers improvement compared to optical-only estimates out to z≈ 1, with stellar masses constrained within a factor of approximately 2.5. When combined with other multiwavelength imaging of the Stripe, including moderate-to-deep ultraviolet (GALEX), optical and mid-infrared (Spitzer-IRAC) coverage, as well as tens of thousands of spectroscopic redshifts, VICS82 gives access to approximately 0.5 Gpc3 of comoving volume. Some of the main science drivers of VICS82 include (a) measuring the stellar mass function of {L}\\star galaxies out to z∼ 1; (b) detecting intermediate-redshift quasars at 2≲ z≲ 3.5; (c) measuring the stellar mass function and baryon census of clusters of galaxies, and (d) performing cross-correlation experiments of cosmic microwave background lensing in the optical/near-infrared that link stellar mass to large-scale dark matter structure. Here we define and describe the survey, highlight some early science results, and present the first public data release, which includes an SDSS-matched catalog as well as the calibrated pixel data themselves.

Chemically Resolved Imaging of Biological Cells and Thin Films by Infrared Scanning Near-Field Optical Microscopy

PubMed Central

Cricenti, Antonio; Generosi, Renato; Luce, Marco; Perfetti, Paolo; Margaritondo, Giorgio; Talley, David; Sanghera, Jas S.; Aggarwal, Ishwar D.; Tolk, Norman H.; Congiu-Castellano, Agostina; Rizzo, Mark A.; Piston, David W.

2003-01-01

The infrared (IR) absorption of a biological system can potentially report on fundamentally important microchemical properties. For example, molecular IR profiles are known to change during increases in metabolic flux, protein phosphorylation, or proteolytic cleavage. However, practical implementation of intracellular IR imaging has been problematic because the diffraction limit of conventional infrared microscopy results in low spatial resolution. We have overcome this limitation by using an IR spectroscopic version of scanning near-field optical microscopy (SNOM), in conjunction with a tunable free-electron laser source. The results presented here clearly reveal different chemical constituents in thin films and biological cells. The space distribution of specific chemical species was obtained by taking SNOM images at IR wavelengths (λ) corresponding to stretch absorption bands of common biochemical bonds, such as the amide bond. In our SNOM implementation, this chemical sensitivity is combined with a lateral resolution of 0.1 μm (≈λ/70), well below the diffraction limit of standard infrared microscopy. The potential applications of this approach touch virtually every aspect of the life sciences and medical research, as well as problems in materials science, chemistry, physics, and environmental research. PMID:14507733

[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

THE TAIWAN ECDFS NEAR-INFRARED SURVEY: VERY BRIGHT END OF THE LUMINOSITY FUNCTION AT z > 7

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsieh, Bau-Ching; Wang, Wei-Hao; Lin, Lihwai

2012-04-10

The primary goal of the Taiwan ECDFS Near-Infrared Survey (TENIS) is to find well-screened galaxy candidates at z > 7 (z' dropout) in the Extended Chandra Deep Field-South (ECDFS). To this end, TENIS provides relatively deep J and K{sub s} data ({approx}25.3 ABmag, 5{sigma}) for an area of 0.5 Multiplication-Sign 0.5 deg. Leveraged with existing data at mid-infrared to optical wavelengths, this allows us to screen for the most luminous high-z objects, which are rare and thus require a survey over a large field to be found. We introduce new color selection criteria to select a z > 7 samplemore » with minimal contaminations from low-z galaxies and Galactic cool stars; to reduce confusion in the relatively low angular resolution Infrared Array Camera (IRAC) images, we introduce a novel deconvolution method to measure the IRAC fluxes of individual sources. Illustrating perhaps the effectiveness at which we screen out interlopers, we find only one z > 7 candidate, TENIS-ZD1. The candidate has a weighted z{sub phot} of 7.8, and its colors and luminosity indicate a young (45M years old) starburst galaxy with a stellar mass of 3.2 Multiplication-Sign 10{sup 10} M{sub Sun }. The result matches with the observational luminosity function analysis and the semianalytic simulation result based on the Millennium Simulations, which may over predict the volume density for high-z massive galaxies. The existence of TENIS-ZD1, if confirmed spectroscopically to be at z > 7, therefore poses a challenge to current theoretical models for how so much mass can accumulate in a galaxy at such a high redshift.« less

Visible/near-infrared spectral diversity from in situ observations of the Bagnold Dune Field sands in Gale Crater, Mars

NASA Astrophysics Data System (ADS)

Johnson, Jeffrey R.; Achilles, Cherie; Bell, James F.; Bender, Steve; Cloutis, Edward; Ehlmann, Bethany; Fraeman, Abigail; Gasnault, Olivier; Hamilton, Victoria E.; Le Mouélic, Stéphane; Maurice, Sylvestre; Pinet, Patrick; Thompson, Lucy; Wellington, Danika; Wiens, Roger C.

2017-12-01

As part of the Bagnold Dune campaign conducted by Mars Science Laboratory rover Curiosity, visible/near-infrared reflectance spectra of dune sands were acquired using Mast Camera (Mastcam) multispectral imaging (445-1013 nm) and Chemistry and Camera (ChemCam) passive point spectroscopy (400-840 nm). By comparing spectra from pristine and rover-disturbed ripple crests and troughs within the dune field, and through analysis of sieved grain size fractions, constraints on mineral segregation from grain sorting could be determined. In general, the dune areas exhibited low relative reflectance, a weak 530 nm absorption band, an absorption band near 620 nm, and a spectral downturn after 685 nm consistent with olivine-bearing sands. The finest grain size fractions occurred within ripple troughs and in the subsurface and typically exhibited the strongest 530 nm bands, highest relative reflectances, and weakest red/near-infrared ratios, consistent with a combination of crystalline and amorphous ferric materials. Coarser-grained samples were the darkest and bluest and exhibited weaker 530 nm bands, lower relative reflectances, and stronger downturns in the near-infrared, consistent with greater proportions of mafic minerals such as olivine and pyroxene. These grains were typically segregated along ripple crests and among the upper surfaces of grain flows in disturbed sands. Sieved dune sands exhibited progressive decreases in reflectance with increasing grain size, as observed in laboratory spectra of olivine size separates. The continuum of spectral features observed between the coarse- and fine-grained dune sands suggests that mafic grains, ferric materials, and air fall dust mix in variable proportions depending on aeolian activity and grain sorting.

LoCuSS: the near-infrared luminosity and weak-lensing mass scaling relation of galaxy clusters

NASA Astrophysics Data System (ADS)

Mulroy, Sarah L.; Smith, Graham P.; Haines, Chris P.; Marrone, Daniel P.; Okabe, Nobuhiro; Pereira, Maria J.; Egami, Eiichi; Babul, Arif; Finoguenov, Alexis; Martino, Rossella

2014-10-01

We present the first scaling relation between weak-lensing galaxy cluster mass, MWL, and near-infrared luminosity, LK. Our results are based on 17 clusters observed with wide-field instruments on Subaru, the United Kingdom Infrared Telescope, the Mayall Telescope, and the MMT. We concentrate on the relation between projected 2D weak-lensing mass and spectroscopically confirmed luminosity within 1 Mpc, modelled as M_WL ∝ LK^b, obtaining a power-law slope of b=0.83^{+0.27}_{-0.24} and an intrinsic scatter of σ _{lnM_WL|LK}=10^{+8}_{-5} per cent. Intrinsic scatter of ˜10 per cent is a consistent feature of our results regardless of how we modify our approach to measuring the relationship between mass and light. For example, deprojecting the mass and measuring both quantities within r500, that is itself obtained from the lensing analysis, yields σ _{lnM_WL|LK}=10^{+7}_{-5} per cent and b=0.97^{+0.17}_{-0.17}. We also find that selecting members based on their (J - K) colours instead of spectroscopic redshifts neither increases the scatter nor modifies the slope. Overall our results indicate that near-infrared luminosity measured on scales comparable with r500 (typically 1 Mpc for our sample) is a low scatter and relatively inexpensive proxy for weak-lensing mass. Near-infrared luminosity may therefore be a useful mass proxy for cluster cosmology experiments.

A Deep Near-Infrared Survey of the N 49 Region around the Soft Gamma-Ray Repeater 0526-66

NASA Technical Reports Server (NTRS)

Klose, S.; Henden, A. A.; Geppert, U.; Greiner, J.; Guetter, H. H.; Hartmann, D. H.; Kouveliotou, C.; Luginbuhl, C. B.; Stecklurn, B.; Vrba, F. J.

2004-01-01

We report the results of a deep near-infrared survey of the vicinity of supernova remnant N49 in the Large Magellanic Cloud (LMC), which contains the soft gamma-ray repeater (SGR) 0526-66. Two of the four confirmed SGRs are potentially associated with compact stellar clusters. We thus searched for a similar association of SGR0526-66, and find the unexplored young stellar cluster SL 463 at a projected distance of approx. 30 pc from the SGR. This constitutes the third cluster-SGR link, and lends support to scenarios in which SGR progenitors originate in young, embedded clusters. If real, the cluster-SGR association constrains the age and thus the initial mass of these stars. In addition, our high-resolution images of the super- nova remnant N49 reveal an area of excess K-band flux in the southeastern part of the SNR. This feature coincides with the maximum flux area at 8.28 microns as detected by the Midcourse Space Experiment (MSX satellite), which we identify with IRAS 052594607.

Preliminary Analysis of Ground-based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Brad

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

Preliminary Analysis of Ground-Based Orbit Determination Accuracy for the Wide Field Infrared Survey Telescope (WFIRST)

NASA Technical Reports Server (NTRS)

Sease, Bradley; Myers, Jessica; Lorah, John; Webster, Cassandra

2017-01-01

The Wide Field Infrared Survey Telescope is a 2.4-meter telescope planned for launch to the Sun-Earth L2 point in 2026. This paper details a preliminary study of the achievable accuracy for WFIRST from ground-based orbit determination routines. The analysis here is divided into two segments. First, a linear covariance analysis of early mission and routine operations provides an estimate of the tracking schedule required to meet mission requirements. Second, a simulated operations'' scenario gives insight into the expected behavior of a daily Extended Kalman Filter orbit estimate over the first mission year given a variety of potential momentum unloading schemes.

A near-infrared spectroscopy routine for unambiguous identification of cryptic ant species

USDA-ARS?s Scientific Manuscript database

The identification of species – of importance for most biological disciplines – is not always straightforward as cryptic species present a hurdle for traditional species discrimination. Fibre-optic near-infrared spectroscopy (NIRS) is a rapid and cheap method for a wide range of different applicatio...

ARNICA, the Arcetri Near-Infrared Camera

NASA Astrophysics Data System (ADS)

Lisi, F.; Baffa, C.; Bilotti, V.; Bonaccini, D.; del Vecchio, C.; Gennari, S.; Hunt, L. K.; Marcucci, G.; Stanga, R.

1996-04-01

ARNICA (ARcetri Near-Infrared CAmera) is the imaging camera for the near-infrared bands between 1.0 and 2.5 microns that the Arcetri Observatory has designed and built for the Infrared Telescope TIRGO located at Gornergrat, Switzerland. We describe the mechanical and optical design of the camera, and report on the astronomical performance of ARNICA as measured during the commissioning runs at the TIRGO (December, 1992 to December 1993), and an observing run at the William Herschel Telescope, Canary Islands (December, 1993). System performance is defined in terms of efficiency of the camera+telescope system and camera sensitivity for extended and point-like sources. (SECTION: Astronomical Instrumentation)

Wide-area remote-sensing system of pollution and gas dispersal by near-infrared absorption based on low-loss optical fiber network

NASA Technical Reports Server (NTRS)

Inaba, H.

1986-01-01

An all optical remote sensing system utilizing long distance, ultralow loss optical fiber networks is studied and discussed for near infrared absorption measurements of combustible and/or explosive gases such as CH4 and C3H8 in our environment, including experimental results achieved in a diameter more than 20 km. The use of a near infrared wavelength range is emphasized.

[Alfalfa quality evaluation in the field by near-infrared reflectance spectroscopy].

PubMed

Xu, Rui-Xuan; Li, Dong-Ning; Yang, Dong-Hai; Lin, Jian-Hai; Xiang, Min; Zhang, Ying-Jun

2013-11-01

To explore the feasibility of using near-infrared reflectance spectroscopy (NIRS) to evaluate alfalfa quality rapidly in the field and try to find the appropriate machine and sample preparation method, the representative population of 170 fresh alfalfa samples collected from different regions with different stages and different cuts were scanned by a portable NIRS spectrometer (1 100 - 1 800 nm). This is the first time to build models of fresh alfalfa to rapidly estimate quality in the field for harvesting in time. The calibrations of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were developed through the partial least squares regression (PLS). The determination coefficients of cross-validation (R2((CV)) were 0.831 4, 0.597 9, 0.803 6, 0.786 1 for DM, CP, NDF, ADF, respectively; the root mean standard error of cross-validation (RMSECV) were 1.241 1, 0.261 4, 0.990 3, 0.830 6; The determination coefficients of validation (R2(V)) were 0.815 0, 0.401 1, 0.784 9, 0.752 1 and the root mean standard errors of validation(RMSEP)were 1.06, 0.31, 0.95, 0.80 for DM, CP, NDF, ADF, respectively. For fresh alfalfa ,the calibration of DM, NDF, ADF can do rough quantitative analysis but the CP's calibration is failed. however, as CP in alfalfa hay is enough for animal and the DM, NDF and ADF is the crucial indicator for evaluating havest time, the model of DM, NDF and ADF can be used for evaluating the alfalfa quality rapidly in the field.

Solvothermally Synthesized Sb2Te3 Platelets Show Unexpected Optical Contrasts in Mid-Infrared Near-Field Scanning Microscopy.

PubMed

Hauer, Benedikt; Saltzmann, Tobias; Simon, Ulrich; Taubner, Thomas

2015-05-13

We report nanoscale-resolved optical investigations on the local material properties of Sb2Te3 hexagonal platelets grown by solvothermal synthesis. Using mid-infrared near-field microscopy, we find a highly symmetric pattern, which is correlated to a growth spiral and which extends over the entire platelet. As the origin of the optical contrast, we identify domains with different densities of charge carriers. On Sb2Te3 samples grown by other means, we did not find a comparable domain structure.

Iron variation within a granitic pluton as determined by near-infrared reflectance

NASA Technical Reports Server (NTRS)

Baird, A. K.

1984-01-01

One-hundred fifty-one previously chemically analyzed samples of tonalite from the Lakeview Mountains pluton, southern California batholith, were analyzed for their iron content using near-infrared spectrophotometry. Compared to the earlier analyses of the same sample set by X-ray fluorescence spectrography, the infrared data have higher analytical variance but clearly define patterns of compositional zonation in the pluton which are closely similar to those patterns obtained from X-ray data; petrogenetic interpretations for the pluton would be the same from either data set. Infrared spectral data can be obtained directly in the field with relatively simple instruments and field measurements can be made to average local heterogeneities that often mask significant plutonic variations.

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).

Three new cool brown dwarfs discovered with the wide-field infrared survey explorer (WISE) and an improved spectrum of the Y0 dwarf wise J041022.71+150248.4

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R.

2014-05-01

As part of a larger search of Wide-field Infrared Survey Explorer (WISE) data for cool brown dwarfs with effective temperatures less than 1000 K, we present the discovery of three new cool brown dwarfs with spectral types later than T7. Using low-resolution, near-infrared spectra obtained with the NASA Infrared Telescope Facility and the Hubble Space Telescope, we derive spectral types of T9.5 for WISE J094305.98+360723.5, T8 for WISE J200050.19+362950.1, and Y0: for WISE J220905.73+271143.9. The identification of WISE J220905.73+271143.9 as a Y dwarf brings the total number of spectroscopically confirmed Y dwarfs to 17. In addition, we present an improvedmore » spectrum (i.e., higher signal-to-noise ratio) of the Y0 dwarf WISE J041022.71+150248.4 that confirms the Cushing et al. classification of Y0. Spectrophotometric distance estimates place all three new brown dwarfs at distances less than 12 pc, with WISE J200050.19+362950.1 lying at a distance of only 3.9-8.0 pc. Finally, we note that brown dwarfs like WISE J200050.19+362950.1 that lie in or near the Galactic plane offer an exciting opportunity to directly measure the mass of a brown dwarf via astrometric microlensing.« less

Fast quantifying collision strength index of ethylene-vinyl acetate copolymer coverings on the fields based on near infrared hyperspectral imaging techniques

PubMed Central

Chen, Y. M.; Lin, P.; He, Y.; He, J. Q.; Zhang, J.; Li, X. L.

2016-01-01

A novel strategy based on the near infrared hyperspectral imaging techniques and chemometrics were explored for fast quantifying the collision strength index of ethylene-vinyl acetate copolymer (EVAC) coverings on the fields. The reflectance spectral data of EVAC coverings was obtained by using the near infrared hyperspectral meter. The collision analysis equipment was employed to measure the collision intensity of EVAC materials. The preprocessing algorithms were firstly performed before the calibration. The algorithms of random frog and successive projection (SP) were applied to extracting the fingerprint wavebands. A correlation model between the significant spectral curves which reflected the cross-linking attributions of the inner organic molecules and the degree of collision strength was set up by taking advantage of the support vector machine regression (SVMR) approach. The SP-SVMR model attained the residual predictive deviation of 3.074, the square of percentage of correlation coefficient of 93.48% and 93.05% and the root mean square error of 1.963 and 2.091 for the calibration and validation sets, respectively, which exhibited the best forecast performance. The results indicated that the approaches of integrating the near infrared hyperspectral imaging techniques with the chemometrics could be utilized to rapidly determine the degree of collision strength of EVAC. PMID:26875544

Near-field investigation of the effect of the array edge on the resonance of loop frequency selective surface elements at mid-infrared wavelengths.

PubMed

Tucker, Eric; D' Archangel, Jeffrey; Raschke, Markus B; Boreman, Glenn

2015-05-04

Mid-infrared scattering scanning near-field optical microscopy, in combination with far-field infrared spectroscopy, and simulations, was employed to investigate the effect of mutual-element coupling towards the edge of arrays of loop elements acting as frequency selective surfaces (FSSs). Two different square loop arrays on ZnS over a ground plane, resonant at 10.3 µm, were investigated. One array had elements that were closely spaced while the other array had elements with greater inter-element spacing. In addition to the dipolar resonance, we observed a new emergent resonance associated with the edge of the closely-spaced array as a finite size effect, due to the broken translational invariance.

A 1500 deg2 near infrared proper motion catalogue from the UKIDSS Large Area Survey

NASA Astrophysics Data System (ADS)

Smith, Leigh; Lucas, P. W.; Burningham, B.; Jones, H. R. A.; Smart, R. L.; Andrei, A. H.; Catalán, S.; Pinfield, D. J.

2014-02-01

The United Kingdom Infrared Deep Sky Survey (UKIDSS) Large Area Survey (LAS) began in 2005, with the start of the UKIDSS programme as a 7 year effort to survey roughly 4000 deg2 at high Galactic latitudes in Y, J, H and K bands. The survey also included a significant quantity of two epoch J band observations, with an epoch baseline greater than 2 years to calculate proper motions. We present a near-infrared proper motion catalogue for the 1500 deg2 of the two epoch LAS data, which includes 135 625 stellar sources and a further 88 324 with ambiguous morphological classifications, all with motions detected above the 5σ level. We developed a custom proper motion pipeline which we describe here. Our catalogue agrees well with the proper motion data supplied for a 300 deg2 subset in the current Wide Field Camera Science Archive (WSA) 10th data release (DR10) catalogue, and in various optical catalogues, but it benefits from a larger matching radius and hence a larger upper proper motion detection limit. We provide absolute proper motions, using LAS galaxies for the relative to absolute correction. By using local second-order polynomial transformations, as opposed to linear transformations in the WSA, we correct better for any local distortions in the focal plane, not including the radial distortion that is removed by the UKIDSS pipeline. We present the results of proper motion searches for new brown dwarfs and white dwarfs. We discuss 41 sources in the WSA DR10 overlap with our catalogue with proper motions >300 mas yr-1, several of which are new detections. We present 15 new candidate ultracool dwarf binary systems.

Infrared Astronomy

NASA Astrophysics Data System (ADS)

Grygar, J.

2018-04-01

Although infrared radiation was described by W. Herschel already in 1800, technical problems delayed its use in astronomy for 160 years. After the invention of a sensitive bolometer and semiconducting CCD arrays for very wide infrared window the progress in the field accelerated. Many high-altitude observatories started their work in the last three decades of XXth century and since 1983 space observatories became most important due to the fact that infrared radiation penetrates through opaque cold shells. Moreover, cosmological expansion of the Universe shifts the maximum of spectral energy of distant hot objects from ultraviolet to near infrared region. Infrared astronomy is also essential for improving our knowledge of the cold universe, particularly for studies about the birth of stars, planetary systems and galaxies.

THE DARKEST SHADOWS: DEEP MID-INFRARED EXTINCTION MAPPING OF A MASSIVE PROTOCLUSTER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butler, Michael J.; Tan, Jonathan C.; Kainulainen, Jouni

We use deep 8 μm Spitzer-IRAC imaging of massive Infrared Dark Cloud (IRDC) G028.37+00.07 to construct a mid-infrared (MIR) extinction map that probes mass surface densities up to Σ ∼ 1 g cm{sup –2} (A{sub V} ∼ 200 mag), amongst the highest values yet probed by extinction mapping. Merging with an NIR extinction map of the region creates a high dynamic range map that reveals structures down to A{sub V} ∼ 1 mag. We utilize the map to: (1) measure a cloud mass ∼7 × 10{sup 4} M {sub ☉} within a radius of ∼8 pc. {sup 13}CO kinematics indicate thatmore » the cloud is gravitationally bound. It thus has the potential to form one of the most massive young star clusters known in the Galaxy. (2) Characterize the structures of 16 massive cores within the IRDC, finding they can be fit by singular polytropic spheres with ρ∝r{sup −k{sub ρ}} and k {sub ρ} = 1.3 ± 0.3. They have Σ-bar ≃0.1--0.4 g cm{sup −2}—relatively low values that, along with their measured cold temperatures, suggest that magnetic fields, rather than accretion-powered radiative heating, are important for controlling fragmentation of these cores. (3) Determine the Σ (equivalently column density or A{sub V} ) probability distribution function (PDF) for a region that is nearly complete for A{sub V} > 3 mag. The PDF is well fit by a single log-normal with mean A-bar {sub V}≃9 mag, high compared to other known clouds. It does not exhibit a separate high-end power law tail, which has been claimed to indicate the importance of self-gravity. However, we suggest that the PDF does result from a self-similar, self-gravitating hierarchy of structures present over a wide range of scales in the cloud.« less

0.4-1.4 μm Visible to Near-Infrared Widely Broadened Super Continuum Generation with Er-doped Ultrashort Pulse Fiber Laser System

NASA Astrophysics Data System (ADS)

Nishizawa, Norihiko; Mitsuzawa, Hideyuki; Sumimura, Kazuhiko

2009-03-01

Visible to near-infrared widely broadened super continuum generation is demonstrated using ultrashort-pulse fiber laser system. Er-doped fiber chirped-pulse amplification system operated at 1550 nm in wavelength is used for the amplifier system, which generated ultrashort-pulse of 112 fs in FWHM with output power of 160 mW, on average. Almost pedestal free 200 fs second harmonic generation pulse is generated at 780 nm region using periodically poled LiNbO3 and conversion efficiency is as high as 37%. 0.45-1.40 μm widely broadened super continuum is generated in highly nonlinear photonic crystal fiber and spectrum flatness is within ±6 dB. All of the fiber devices are fusion spliced so that this system shows a good stability.

Quantitative Near-field Microscopy of Heterogeneous and Correlated Electron Oxides

NASA Astrophysics Data System (ADS)

McLeod, Alexander Swinton

Scanning near-field optical microscopy (SNOM) is a novel scanning probe microscopy technique capable of circumventing the conventional diffraction limit of light, affording unparalleled optical resolution (down to 10 nanometers) even for radiation in the infrared and terahertz energy regimes, with light wavelengths exceeding 10 micrometers. However, although this technique has been developed and employed for more than a decade to a qualitatively impressive effect, researchers have lacked a practically quantitative grasp of its capabilities, and its application scope has so far remained restricted by implementations limited to ambient atmospheric conditions. The two-fold objective of this dissertation work has been to address both these shortcomings. The first half of the dissertation presents a realistic, semi-analytic, and benchmarked theoretical description of probe-sample near-field interactions that form the basis of SNOM. Owing its name to the efficient nano-focusing of light at a sharp metallic apex, the "lightning rod model" of probe-sample near-field interactions is mathematically developed from a flexible and realistic scattering formalism. Powerful and practical applications are demonstrated through the accurate prediction of spectroscopic near-field optical contrasts, as well as the "inversion" of these spectroscopic contrasts into a quantitative description of material optical properties. Thus enabled, this thesis work proceeds to present quantitative applications of infrared near-field spectroscopy to investigate nano-resolved chemical compositions in a diverse host of samples, including technologically relevant lithium ion battery materials, astrophysical planetary materials, and invaluable returned extraterrestrial samples. The second half of the dissertation presents the design, construction, and demonstration of a sophisticated low-temperature scanning near-field infrared microscope. This instrument operates in an ultra-high vacuum environment

Aqueous synthesis of near-infrared highly fluorescent platinum nanoclusters

NASA Astrophysics Data System (ADS)

García Fernández, Jenifer; Trapiella-Alfonso, Laura; Costa-Fernández, José M.; Pereiro, Rosario; Sanz-Medel, Alfredo

2015-05-01

A one-step synthesis of near infrared fluorescent platinum nanoclusters (PtNCs) in aqueous medium is described. The proposed optimized procedure for PtNC synthesis is rather simple, fast and it is based on the direct metal reduction with NaBH4. Bidentated thiol ligands (lipoic acid) were selected as nanoclusters stabilizers in water media. The structural characterization revealed attractive features of the PtNCs, including small size, high water solubility, near-infrared luminescence centered at 680 nm, long-term stability and the highest quantum yield in water reported so far (47%) for PtNCs. Moreover, their stability in different pH media and an ionic strength of 0.2 M NaCl was studied and no significant changes in fluorescence emission were detected. In brief, they offer a new type of fluorescent noble metal nanoprobe with a great potential to be applied in several fields, including biolabeling and imaging experiments.

Distortion of Magnetic Fields in a Starless Core: Near-infrared Polarimetry of FeSt 1–457

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kandori, Ryo; Tamura, Motohide; Kusakabe, Nobuhiko

Magnetic fields are believed to play an important role in controlling the stability and contraction of the dense condensations of gas and dust that lead to the formation of stars and planetary systems. In the present study, the magnetic field of FeSt 1–457, a cold starless molecular cloud core, was mapped on the basis of the polarized near-infrared light from 185 background stars after being dichroically absorbed by dust aligned with the magnetic field in the core. A distinct “hourglass-shaped” magnetic field was identified in the region of the core, and was interpreted as the first evidence of a magneticmore » field structure distorted by mass condensation in a starless core. The steep curvature of the magnetic field lines obtained in the present study indicates that the distortion was mainly created during the formation phase of the dense core. The derived mass-to-magnetic flux ratio indicates that the core is in a magnetically supercritical state. However, the stability of the core can be considered to be in a nearly critical state if the additional contributions from the thermal and turbulent support are included. Further diffusion of the magnetic field and/or turbulent dissipation would cause the onset of the dynamical collapse of the core. The geometrical relationship between the direction of the magnetic field lines and the elongation of the core was found to be in good agreement with theoretical predictions for the formation of Sun-like stars under the influence of a magnetic field.« less

Near-infrared induced optical quenching effects on mid-infrared quantum cascade lasers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Dingkai, E-mail: dingk1@umbc.edu; Talukder, Muhammad Anisuzzaman; Chen, Xing

In space communications, atmospheric absorption and Rayleigh scattering are the dominant channel impairments. Transmission using mid-infrared (MIR) wavelengths offers the benefits of lower loss and less scintillation effects. In this work, we report the telecom wavelengths (1.55 μm and 1.3 μm) induced optical quenching effects on MIR quantum cascade lasers (QCLs), when QCLs are operated well above their thresholds. The QCL output power can be near 100% quenched using 20 mW of near-infrared (NIR) power, and the quenching effect depends on the input NIR intensity as well as wavelength. Time resolved measurement was conducted to explore the quenching mechanism. The measured recovery timemore » is around 14 ns, which indicates that NIR generated electron-hole pairs may play a key role in the quenching process. The photocarrier created local field and band bending can effectively deteriorate the dipole transition matrix element and quench the QCL. As a result, MIR QCLs can be used as an optical modulator and switch controlled by NIR lasers. They can also be used as “converters” to convert telecom optical signals into MIR optical signals.« less

Near-infrared transillumination photography of intraocular tumours.

PubMed

Krohn, Jørgen; Ulltang, Erlend; Kjersem, Bård

2013-10-01

To present a technique for near-infrared transillumination imaging of intraocular tumours based on the modifications of a conventional digital slit lamp camera system. The Haag-Streit Photo-Slit Lamp BX 900 (Haag-Streit AG) was used for transillumination photography by gently pressing the tip of the background illumination cable against the surface of the patient's eye. Thus the light from the flash unit was transmitted into the eye, leading to improved illumination and image resolution. The modification for near-infrared photography was done by replacing the original camera with a Canon EOS 30D (Canon Inc) converted by Advanced Camera Services Ltd. In this camera, the infrared blocking filter was exchanged for a 720 nm long-pass filter, so that the near-infrared part of the spectrum was recorded by the sensor. The technique was applied in eight patients: three with anterior choroidal melanoma, three with ciliary body melanoma and two with ocular pigment alterations. The good diagnostic quality of the photographs made it possible to evaluate the exact location and extent of the lesions in relation to pigmented intraocular landmarks such as the ora serrata and ciliary body. The photographic procedure did not lead to any complications. We recommend near-infrared transillumination photography as a supplementary diagnostic tool for the evaluation and documentation of anteriorly located intraocular tumours.

MODIS airborne simulator visible and near-infrared calibration, 1992 ASTEX field experiment. Calibration version: ASTEX King 1.0

NASA Technical Reports Server (NTRS)

Arnold, G. Thomas; Fitzgerald, Michael; Grant, Patrick S.; King, Michael D.

1994-01-01

Calibration of the visible and near-infrared (near-IR) channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1992 Atlantic Stratocumulus Transition Experiment (ASTEX) field deployment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Tests during the ASTEX deployment were conducted to calibrate the hemisphere and then the MAS. This report summarizes the ASTEX hemisphere calibration, and then describes how the MAS was calibrated from the hemisphere data. All MAS calibration measurements are presented and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. In addition, comparisons to an independent MAS calibration by Ames personnel using their 30-inch integrating sphere is discussed.

Intraoperative near-infrared autofluorescence imaging of parathyroid glands.

PubMed

Ladurner, Roland; Sommerey, Sandra; Arabi, Nora Al; Hallfeldt, Klaus K J; Stepp, Herbert; Gallwas, Julia K S

2017-08-01

To identify parathyroid glands intraoperatively by exposing their autofluorescence using near-infrared light. Fluorescence imaging was carried out during minimally invasive and open parathyroid and thyroid surgery. After identification, the parathyroid glands as well as the surrounding tissue were exposed to near-infrared (NIR) light with a wavelength of 690-770 nm using a modified Karl Storz near-infrared/indocyanine green (NIR/ICG) endoscopic system. Parathyroid tissue was expected to show near-infrared autofluorescence, captured in the blue channel of the camera. Whenever possible the visual identification of parathyroid tissue was confirmed histologically. In preliminary investigations, using the original NIR/ICG endoscopic system we noticed considerable interference of light in the blue channel overlying the autofluorescence. Therefore, we modified the light source by interposing additional filters. In a second series, we investigated 35 parathyroid glands from 25 patients. Twenty-seven glands were identified correctly based on NIR autofluorescence. Regarding the extent of autofluorescence, there were no noticeable differences between parathyroid adenomas, hyperplasia and normal parathyroid glands. In contrast, thyroid tissue, lymph nodes and adipose tissue revealed no substantial autofluorescence. Parathyroid tissue is characterized by showing autofluorescence in the near-infrared spectrum. This effect can be used to distinguish parathyroid glands from other cervical tissue entities.

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.

Near-Infrared Plasmon-Assisted Water Oxidation.

PubMed

Nishijima, Yoshiaki; Ueno, Kosei; Kotake, Yuki; Murakoshi, Kei; Inoue, Haruo; Misawa, Hiroaki

2012-05-17

We report the stoichiometric evolution of oxygen via water oxidation by irradiating a plasmon-enhanced photocurrent generation system with near-infrared light (λ: 1000 nm), in which gold nanostructures were arrayed on the surface of TiO2 electrode. It is considered that multiple electron holes generated by plasmon-induced charge excitation led to the effective recovery of water oxidation after the electron transfer from gold to TiO2. The proposed system containing a gold nanostructured TiO2 electrode may be a promising artificial photosynthetic system using near-infrared light.

Image-Guided Surgery using Invisible Near-Infrared Light: Fundamentals of Clinical Translation

PubMed Central

Gioux, Sylvain; Choi, Hak Soo; Frangioni, John V.

2011-01-01

The field of biomedical optics has matured rapidly over the last decade and is poised to make a significant impact on patient care. In particular, wide-field (typically > 5 cm), planar, near-infrared (NIR) fluorescence imaging has the potential to revolutionize human surgery by providing real-time image guidance to surgeons for tissue that needs to be resected, such as tumors, and tissue that needs to be avoided, such as blood vessels and nerves. However, to become a clinical reality, optimized imaging systems and NIR fluorescent contrast agents will be needed. In this review, we introduce the principles of NIR fluorescence imaging, analyze existing NIR fluorescence imaging systems, and discuss the key parameters that guide contrast agent development. We also introduce the complexities surrounding clinical translation using our experience with the Fluorescence-Assisted Resection and Exploration (FLARE™) imaging system as an example. Finally, we introduce state-of-the-art optical imaging techniques that might someday improve image-guided surgery even further. PMID:20868625

MODIS airborne simulator visible and near-infrared calibration, 1991 FIRE-Cirrus field experiment. Calibration version: FIRE King 1.1

NASA Technical Reports Server (NTRS)

Arnold, G. Thomas; Fitzgerald, Michael; Grant, Patrick S.; King, Michael D.

1994-01-01

Calibration of the visible and near-infrared channels of the MODIS Airborne Simulator (MAS) is derived from observations of a calibrated light source. For the 1991 FIRE-Cirrus field experiment, the calibrated light source was the NASA Goddard 48-inch integrating hemisphere. Laboratory tests during the FIRE Cirrus field experiment were conducted to calibrate the hemisphere and from the hemisphere to the MAS. The purpose of this report is to summarize the FIRE-Cirrus hemisphere calibration, and then describe how the MAS was calibrated from observations of the hemisphere data. All MAS calibration measurements are presented, and determination of the MAS calibration coefficients (raw counts to radiance conversion) is discussed. Thermal sensitivity of the MAS visible and near-infrared calibration is also discussed. Typically, the MAS in-flight is 30 to 60 degrees C colder than the room temperature laboratory calibration. Results from in-flight temperature measurements and tests of the MAS in a cold chamber are given, and from these, equations are derived to adjust the MAS in-flight data to what the value would be at laboratory conditions. For FIRE-Cirrus data, only channels 3 through 6 were found to be temperature sensitive. The final section of this report describes comparisons to an independent MAS (room temperature) calibration by Ames personnel using their 30-inch integrating sphere.

Near-infrared spectroscopic tissue imaging for medical applications

DOEpatents

Demos,; Stavros, Staggs [Livermore, CA; Michael, C [Tracy, CA

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.

Near-infrared spectroscopic tissue imaging for medical applications

DOEpatents

Demos, Stavros [Livermore, CA; Staggs, Michael C [Tracy, CA

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.

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.

Near-inertial waves and deep ocean mixing

NASA Astrophysics Data System (ADS)

Shrira, V. I.; Townsend, W. A.

2013-07-01

For the existing pattern of global oceanic circulation to exist, there should be sufficiently strong turbulent mixing in the abyssal ocean, the mechanisms of which are not well understood as yet. The review discusses a plausible mechanism of deep ocean mixing caused by near-inertial waves in the abyssal ocean. It is well known how winds in the atmosphere generate near-inertial waves in the upper ocean, which then propagate downwards losing their energy in the process; only a fraction of the energy at the surface reaches the abyssal ocean. An open question is whether and, if yes, how these weakened inertial motions could cause mixing in the deep. We review the progress in the mathematical description of a mechanism that results in an intense breaking of near-inertial waves near the bottom of the ocean and thus enhances the mixing. We give an overview of the present state of understanding of the problem covering both the published and the unpublished results; we also outline the key open questions. For typical ocean stratification, the account of the horizontal component of the Earth's rotation leads to the existence of near-bottom wide waveguides for near-inertial waves. Due to the β-effect these waveguides are narrowing in the poleward direction. Near-inertial waves propagating poleward get trapped in the waveguides; we describe how in the process these waves are focusing more and more in the vertical direction, while simultaneously their group velocity tends to zero and wave-induced vertical shear significantly increases. This causes the development of shear instability, which is interpreted as wave breaking. Remarkably, this mechanism of local intensification of turbulent mixing in the abyssal ocean can be adequately described within the framework of linear theory. The qualitative picture is similar to wind wave breaking on a beach: the abyssal ocean always acts as a surf zone for near-inertial waves.

Infrared hyperbolic metasurface based on nanostructured van der Waals materials

NASA Astrophysics Data System (ADS)

Li, Peining; Dolado, Irene; Alfaro-Mozaz, Francisco Javier; Casanova, Fèlix; Hueso, Luis E.; Liu, Song; Edgar, James H.; Nikitin, Alexey Y.; Vélez, Saül; Hillenbrand, Rainer

2018-02-01

Metasurfaces with strongly anisotropic optical properties can support deep subwavelength-scale confined electromagnetic waves (polaritons), which promise opportunities for controlling light in photonic and optoelectronic applications. We developed a mid-infrared hyperbolic metasurface by nanostructuring a thin layer of hexagonal boron nitride that supports deep subwavelength-scale phonon polaritons that propagate with in-plane hyperbolic dispersion. By applying an infrared nanoimaging technique, we visualize the concave (anomalous) wavefronts of a diverging polariton beam, which represent a landmark feature of hyperbolic polaritons. The results illustrate how near-field microscopy can be applied to reveal the exotic wavefronts of polaritons in anisotropic materials and demonstrate that nanostructured van der Waals materials can form a highly variable and compact platform for hyperbolic infrared metasurface devices and circuits.

In-line interferometer for broadband near-field scanning optical spectroscopy.

PubMed

Brauer, Jens; Zhan, Jinxin; Chimeh, Abbas; Korte, Anke; Lienau, Christoph; Gross, Petra

2017-06-26

We present and investigate a novel approach towards broad-bandwidth near-field scanning optical spectroscopy based on an in-line interferometer for homodyne mixing of the near field and a reference field. In scattering-type scanning near-field optical spectroscopy, the near-field signal is usually obscured by a large amount of unwanted background scattering from the probe shaft and the sample. Here we increase the light reflected from the sample by a semi-transparent gold layer and use it as a broad-bandwidth, phase-stable reference field to amplify the near-field signal in the visible and near-infrared spectral range. We experimentally demonstrate that this efficiently suppresses the unwanted background signal in monochromatic near-field measurements. For rapid acquisition of complete broad-bandwidth spectra we employ a monochromator and a fast line camera. Using this fast acquisition of spectra and the in-line interferometer we demonstrate the measurement of pure near-field spectra. The experimental observations are quantitatively explained by analytical expressions for the measured optical signals, based on Fourier decomposition of background and near field. The theoretical model and in-line interferometer together form an important step towards broad-bandwidth near-field scanning optical spectroscopy.

Near-field effects of asteroid impacts in deep water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gisler, Galen R; Weaver, Robert P; Gittings, Michael L

2009-06-11

Our previous work has shown that ocean impacts of asteroids below 500 m in diameter do not produce devastating long-distance tsunamis. Nevertheless, a significant portion of the ocean lies close enough to land that near-field effects may prove to be the greatest danger from asteroid impacts in the ocean. Crown splashes and central jets that rise up many kilometres into the atmosphere can produce, upon their collapse, highly non-linear breaking waves that could devastate shorelines within a hundred kilometres of the impact site. We present illustrative calculations, in two and three dimensions, of such impacts for a range of asteroidmore » sizes and impact angles. We find that, as for land impacts, the greatest dangers from oceanic impacts are the short-term near-field, and long-term atmospheric effects.« less

[Research progress and application prospect of near infrared spectroscopy in soil nutrition analysis].

PubMed

Ding, Hai-quan; Lu, Qi-peng

2012-01-01

"Digital agriculture" or "precision agriculture" is an important direction of modern agriculture technique. It is the combination of the modern information technique and traditional agriculture and becomes a hotspot field in international agriculture research in recent years. As a nondestructive, real-time, effective and exact analysis technique, near infrared spectroscopy, by which precision agriculture could be carried out, has vast prospect in agrology and gradually gained the recognition. The present paper intends to review the basic theory of near infrared spectroscopy and its applications in the field of agrology, pointing out that the direction of NIR in agrology should based on portable NIR spectrograph in order to acquire qualitative or quantitative information from real-time measuring in field. In addition, NIRS could be combined with space remote sensing to macroscopically control the way crop is growing and the nutrition crops need, to change the current state of our country's agriculture radically.

Smart pH-responsive upconversion nanoparticles for enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

PubMed

Wang, Sheng; Zhang, Lei; Dong, Chunhong; Su, Lin; Wang, Hanjie; Chang, Jin

2015-01-01

A smart pH-responsive photodynamic therapy system based on upconversion nanoparticle loaded PEG coated polymeric lipid vesicles (RB-UPPLVs) was designed and prepared. These RB-UPPLVs which are promising agents for deep cancer photodynamic therapy applications can achieve enhanced tumor cellular internalization and near-infrared light-triggered photodynamic therapy.

A comparison of the near-infrared spectral features of early-type galaxies in the Coma Cluster, the Virgo cluster and the field

NASA Technical Reports Server (NTRS)

Houdashelt, Mark L.; Frogel, Jay A.

1993-01-01

Earlier researchers derived the relative distance between the Coma and Virgo clusters from color-magnitude relations of the early-type galaxies in each cluster. They found that the derived distance was color-dependent and concluded that the galaxies of similar luminosity in the two clusters differ in their red stellar populations. More recently, the color-dependence of the Coma-Virgo distance modulus has been called into question. However, because these two clusters differ so dramatically in their morphologies and kinematics, it is plausible that the star formation histories of the member galaxies also differed. If the conclusions of earlier researchers are indeed correct, then some signature of the resulting stellar population differences should appear in the near-infrared and/or infrared light of the respective galaxies. We have collected near-infrared spectra of 17 Virgo and 10 Coma early-type galaxies; this sample spans about four magnitudes in luminosity in each cluster. Seven field E/S0 galaxies have been observed for comparison. Pseudo-equivalent widths have been measured for all of the field galaxies, all but one of the Virgo members, and five of the Coma galaxies. The features examined are sensitive to the temperature, metallicity, and surface gravity of the reddest stars. A preliminary analysis of these spectral features has been performed, and, with a few notable exceptions, the measured pseudo-equivalent widths agree well with previously published values.

Addressing Thermal Model Run Time Concerns of the Wide Field Infrared Survey Telescope using Astrophysics Focused Telescope Assets (WFIRST-AFTA)

NASA Technical Reports Server (NTRS)

Peabody, Hume; Guerrero, Sergio; Hawk, John; Rodriguez, Juan; McDonald, Carson; Jackson, Cliff

2016-01-01

The Wide Field Infrared Survey Telescope using Astrophysics Focused Telescope Assets (WFIRST-AFTA) utilizes an existing 2.4 m diameter Hubble sized telescope donated from elsewhere in the federal government for near-infrared sky surveys and Exoplanet searches to answer crucial questions about the universe and dark energy. The WFIRST design continues to increase in maturity, detail, and complexity with each design cycle leading to a Mission Concept Review and entrance to the Mission Formulation Phase. Each cycle has required a Structural-Thermal-Optical-Performance (STOP) analysis to ensure the design can meet the stringent pointing and stability requirements. As such, the models have also grown in size and complexity leading to increased model run time. This paper addresses efforts to reduce the run time while still maintaining sufficient accuracy for STOP analyses. A technique was developed to identify slews between observing orientations that were sufficiently different to warrant recalculation of the environmental fluxes to reduce the total number of radiation calculation points. The inclusion of a cryocooler fluid loop in the model also forced smaller time-steps than desired, which greatly increases the overall run time. The analysis of this fluid model required mitigation to drive the run time down by solving portions of the model at different time scales. Lastly, investigations were made into the impact of the removal of small radiation couplings on run time and accuracy. Use of these techniques allowed the models to produce meaningful results within reasonable run times to meet project schedule deadlines.

Near-Infrared to Visible Organic Upconversion Devices Based on Organic Light-Emitting Field Effect Transistors.

PubMed

Li, Dongwei; Hu, Yongsheng; Zhang, Nan; Lv, Ying; Lin, Jie; Guo, Xiaoyang; Fan, Yi; Luo, Jinsong; Liu, Xingyuan

2017-10-18

The near-infrared (NIR) to visible upconversion devices have attracted great attention because of their potential applications in the fields of night vision, medical imaging, and military security. Herein, a novel all-organic upconversion device architecture has been first proposed and developed by incorporating a NIR absorption layer between the carrier transport layer and the emission layer in heterostructured organic light-emitting field effect transistors (OLEFETs). The as-prepared devices show a typical photon-to-photon upconversion efficiency as high as 7% (maximum of 28.7% under low incident NIR power intensity) and millisecond-scale response time, which are the highest upconversion efficiency and one of the fastest response time among organic upconversion devices as referred to the previous reports up to now. The high upconversion performance mainly originates from the gain mechanism of field-effect transistor structures and the unique advantage of OLEFETs to balance between the photodetection and light emission. Meanwhile, the strategy of OLEFETs also offers the advantage of high integration so that no extra OLED is needed in the organic upconversion devices. The results would pave way for low-cost, flexible and portable organic upconversion devices with high efficiency and simplified processing.

The Hubble Space Telescope: UV, Visible, and Near-Infrared Pursuits

NASA Technical Reports Server (NTRS)

Wiseman, Jennifer

2010-01-01

The Hubble Space Telescope continues to push the limits on world-class astrophysics. Cameras including the Advanced Camera for Surveys and the new panchromatic Wide Field Camera 3 which was installed nu last year's successful servicing mission S2N4,o{fer imaging from near-infrared through ultraviolet wavelengths. Spectroscopic studies of sources from black holes to exoplanet atmospheres are making great advances through the versatile use of STIS, the Space Telescope Imaging Spectrograph. The new Cosmic Origins Spectrograph, also installed last year, is the most sensitive UV spectrograph to fly io space and is uniquely suited to address particular scientific questions on galaxy halos, the intergalactic medium, and the cosmic web. With these outstanding capabilities on HST come complex needs for laboratory astrophysics support including atomic and line identification data. I will provide an overview of Hubble's current capabilities and the scientific programs and goals that particularly benefit from the studies of laboratory astrophysics.

Deep Imaging of the HCG 95 Field. I. Ultra-diffuse Galaxies

NASA Astrophysics Data System (ADS)

Shi, Dong Dong; Zheng, Xian Zhong; Zhao, Hai Bin; Pan, Zhi Zheng; Li, Bin; Zou, Hu; Zhou, Xu; Guo, KeXin; An, Fang Xia; Li, Yu Bin

2017-09-01

We present a detection of 89 candidates of ultra-diffuse galaxies (UDGs) in a 4.9 degree2 field centered on the Hickson Compact Group 95 (HCG 95) using deep g- and r-band images taken with the Chinese Near Object Survey Telescope. This field contains one rich galaxy cluster (Abell 2588 at z = 0.199) and two poor clusters (Pegasus I at z = 0.013 and Pegasus II at z = 0.040). The 89 candidates are likely associated with the two poor clusters, giving about 50-60 true UDGs with a half-light radius {r}{{e}}> 1.5 {kpc} and a central surface brightness μ (g,0)> 24.0 mag arcsec-2. Deep z\\prime -band images are available for 84 of the 89 galaxies from the Dark Energy Camera Legacy Survey (DECaLS), confirming that these galaxies have an extremely low central surface brightness. Moreover, our UDG candidates are spread over a wide range in g - r color, and ˜26% are as blue as normal star-forming galaxies, which is suggestive of young UDGs that are still in formation. Interestingly, we find that one UDG linked with HCG 95 is a gas-rich galaxy with H I mass 1.1× {10}9 M ⊙ detected by the Very Large Array, and has a stellar mass of {M}\\star ˜ 1.8× {10}8 M ⊙. This indicates that UDGs at least partially overlap with the population of nearly dark galaxies found in deep H I surveys. Our results show that the high abundance of blue UDGs in the HCG 95 field is favored by the environment of poor galaxy clusters residing in H I-rich large-scale structures.

Portable wide-field hand-held NIR scanner

NASA Astrophysics Data System (ADS)

Jung, Young-Jin; Roman, Manuela; Carrasquilla, Jennifer; Erickson, Sarah J.; Godavarty, Anuradha

2013-03-01

Near-infrared (NIR) optical imaging modality is one of the widely used medical imaging techniques for breast cancer imaging, functional brain mapping, and many other applications. However, conventional NIR imaging systems are bulky and expensive, thereby limiting their accelerated clinical translation. Herein a new compact (6 × 7 × 12 cm3), cost-effective, and wide-field NIR scanner has been developed towards contact as well as no-contact based real-time imaging in both reflectance and transmission mode. The scanner mainly consists of an NIR source light (between 700- 900 nm), an NIR sensitive CCD camera, and a custom-developed image acquisition and processing software to image an area of 12 cm2. Phantom experiments have been conducted to estimate the feasibility of diffuse optical imaging by using Indian-Ink as absorption-based contrast agents. As a result, the developed NIR system measured the light intensity change in absorption-contrasted target up to 4 cm depth under transillumination mode. Preliminary in-vivo studies demonstrated the feasibility of real-time monitoring of blood flow changes. Currently, extensive in-vivo studies are carried out using the ultra-portable NIR scanner in order to assess the potential of the imager towards breast imaging..

A NEW INFRARED COLOR CRITERION FOR THE SELECTION OF 0 < z < 7 AGNs: APPLICATION TO DEEP FIELDS AND IMPLICATIONS FOR JWST SURVEYS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Messias, H.; Afonso, J.; Salvato, M.

2012-08-01

It is widely accepted that observations at mid-infrared (mid-IR) wavelengths enable the selection of galaxies with nuclear activity, which may not be revealed even in the deepest X-ray surveys. Many mid-IR color-color criteria have been explored to accomplish this goal and tested thoroughly in the literature. Besides missing many low-luminosity active galactic nuclei (AGNs), one of the main conclusions is that, with increasing redshift, the contamination by non-active galaxies becomes significant (especially at z {approx}> 2.5). This is problematic for the study of the AGN phenomenon in the early universe, the main goal of many of the current and futuremore » deep extragalactic surveys. In this work new near- and mid-IR color diagnostics are explored, aiming for improved efficiency-better completeness and less contamination-in selecting AGNs out to very high redshifts. We restrict our study to the James Webb Space Telescope wavelength range (0.6-27 {mu}m). The criteria are created based on the predictions by state-of-the-art galaxy and AGN templates covering a wide variety of galaxy properties, and tested against control samples with deep multi-wavelength coverage (ranging from the X-rays to radio frequencies). We show that the colors K{sub s} - [4.5], [4.5] - [8.0], and [8.0] - [24] are ideal as AGN/non-AGN diagnostics at, respectively, z {approx}< 1, 1 {approx}< z {approx}< 2.5, and z {approx}> 2.5-3. However, when the source redshift is unknown, these colors should be combined. We thus develop an improved IR criterion (using K{sub s} and IRAC bands, KI) as a new alternative at z {approx}< 2.5. KI does not show improved completeness (50%-60% overall) in comparison to commonly used Infrared Array Camera (IRAC) based AGN criteria, but is less affected by non-AGN contamination (revealing a >50%-90% level of successful AGN selection). We also propose KIM (using K{sub s} , IRAC, and MIPS 24 {mu}m bands, KIM), which aims to select AGN hosts from local distances to as

[Ultra] luminous infrared galaxies selected at 90 μm in the AKARI deep field: a study of AGN types contributing to their infrared emission

NASA Astrophysics Data System (ADS)

Małek, K.; Bankowicz, M.; Pollo, A.; Buat, V.; Takeuchi, T. T.; Burgarella, D.; Goto, T.; Malkan, M.; Matsuhara, H.

2017-02-01

Aims: The aim of this work is to characterize physical properties of ultra luminous infrared galaxies (ULIRGs) and luminous infrared galaxies (LIRGs) detected in the far-infrared (FIR) 90 μm band in the AKARI Deep Field-South (ADF-S) survey. In particular, we want to estimate the active galactic nucleus (AGN) contribution to the LIRGs and ULIRGs' infrared emission and which types of AGNs are related to their activity. Methods: We examined 69 galaxies at redshift ≥0.05 detected at 90 μm by the AKARI satellite in the ADF-S, with optical counterparts and spectral coverage from the ultraviolet to the FIR. We used two independent spectral energy distribution fitting codes: one fitting the SED from FIR to FUV (CIGALE) (we use the results from CIGALE as a reference) and gray-body + power spectrum fit for the infrared part of the spectra (CMCIRSED) in order to identify a subsample of ULIRGs and LIRGs, and to estimate their properties. Results: Based on the CIGALE SED fitting, we have found that LIRGs and ULIRGs selected at the 90 μm AKARI band compose 56% of our sample (we found 17 ULIRGs and 22 LIRGs, spanning over the redshift range 0.06 infrared wavelengths. We have detected a significant AGN contribution to the mid-infrared luminosity for 63% of LIRGs and ULIRGs. Our LIRGs contain Type 1, Type 2, and intermediate types of AGN, whereas for ULIRGs, a majority (more than 50%) of AGN emission originates from Type 2 AGNs. The temperature-luminosity and temperature-mass relations for the dust component of ADF-S LIRGs and ULIRGs indicate that these relations are shaped by the dust mass and not by the increased dust heating. Conclusions: We conclude that LIRGs contain Type 1, Type 2, and intermediate types of AGNs, with an AGN contribution to the mid infrared emission at the median level of 13 ± 3

The Y-type Brown Dwarfs: Estimates of Mass and Age from New Astrometry, Homogenized Photometry, and Near-infrared Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leggett, S. K.; Tremblin, P.; Esplin, T. L.

The survey of the mid-infrared sky by the Wide-field Infrared Survey Explorer ( WISE ) led to the discovery of extremely cold, low-mass brown dwarfs, classified as Y dwarfs, which extend the T class to lower temperatures. Twenty-four Y dwarfs are known at the time of writing. Here we present improved parallaxes for four of these, determined using Spitzer images. We give new photometry for four late-type T and three Y dwarfs and new spectra of three Y dwarfs, obtained at Gemini Observatory. We also present previously unpublished photometry taken from HST , ESO, Spitzer , and WISE archives ofmore » 11 late-type T and 9 Y dwarfs. The near-infrared data are put onto the same photometric system, forming a homogeneous data set for the coolest brown dwarfs. We compare recent models to our photometric and spectroscopic data set. We confirm that nonequilibrium atmospheric chemistry is important for these objects. Nonequilibrium cloud-free models reproduce well the near-infrared spectra and mid-infrared photometry for the warmer Y dwarfs with 425 ≤ T {sub eff} (K) ≤ 450. A small amount of cloud cover may improve the model fits in the near-infrared for the Y dwarfs with 325 ≤ T {sub eff} (K) ≤ 375. Neither cloudy nor cloud-free models reproduce the near-infrared photometry for the T {sub eff} = 250 K Y dwarf W0855. We use the mid-infrared region, where most of the flux originates, to constrain our models of W0855. We find that W0855 likely has a mass of 1.5–8 Jupiter masses and an age of 0.3–6 Gyr. The Y dwarfs with measured parallaxes are within 20 pc of the Sun and have tangential velocities typical of the thin disk. The metallicities and ages we derive for the sample are generally solar-like. We estimate that the known Y dwarfs are 3 to 20 Jupiter-mass objects with ages of 0.6–8.5 Gyr.« less

Algorithm for removing scalp signals from functional near-infrared spectroscopy signals in real time using multidistance optodes.

PubMed

Kiguchi, Masashi; Funane, Tsukasa

2014-11-01

A real-time algorithm for removing scalp-blood signals from functional near-infrared spectroscopy signals is proposed. Scalp and deep signals have different dependencies on the source-detector distance. These signals were separated using this characteristic. The algorithm was validated through an experiment using a dynamic phantom in which shallow and deep absorptions were independently changed. The algorithm for measurement of oxygenated and deoxygenated hemoglobins using two wavelengths was explicitly obtained. This algorithm is potentially useful for real-time systems, e.g., brain-computer interfaces and neuro-feedback systems.

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.

Eye safety related to near infrared radiation exposure to biometric devices.

PubMed

Kourkoumelis, Nikolaos; Tzaphlidou, Margaret

2011-03-01

Biometrics has become an emerging field of technology due to its intrinsic security features concerning the identification of individuals by means of measurable biological characteristics. Two of the most promising biometric modalities are iris and retina recognition, which primarily use nonionizing radiation in the infrared region. Illumination of the eye is achieved by infrared light emitting diodes (LEDs). Even if few LED sources are capable of causing direct eye damage as they emit incoherent light, there is a growing concern about the possible use of LED arrays that might pose a potential threat. Exposure to intense coherent infrared radiation has been proven to have significant effects on living tissues. The purpose of this study is to explore the biological effects arising from exposing the eye to near infrared radiation with reference to international legislation.

A deep near-infrared spectroscopic survey of the Scutum-Crux arm for Wolf-Rayet stars

NASA Astrophysics Data System (ADS)

Rosslowe, C. K.; Crowther, Paul A.

2018-01-01

We present a New Technology Telescope/Son-of-Isaac spectroscopic survey of infrared selected Wolf-Rayet (WR) candidates in the Scutum-Crux spiral arm (298° ≤ l ≤ 340°, |b| ≤ 0.5°. We obtained near-IR spectra of 127 candidates, revealing 17 WR stars - a ∼13 per cent success rate - of which 16 are newly identified here. The majority of the new WR stars are classified as narrow-lined WN5-7 stars, with two broad-lined WN4-6 stars and three WC6-8 stars. The new stars, with distances estimated from previous absolute magnitude calibrations, have no obvious association with the Scutum-Crux arm. Refined near-infrared (YHJK) classification criteria based on over a hundred Galactic and Magellanic Cloud WR stars, providing diagnostics for hydrogen in WN stars, plus the identification of WO stars and intermediate WN/C stars. Finally, we find that only a quarter of WR stars in the survey region are associated with star clusters and/or H II regions, with similar statistics found for luminous blue variables (LBVs) in the Milky Way. The relative isolation of evolved massive stars is discussed, together with the significance of the co-location of LBVs and WR stars in young star clusters.

Managing the Development of the Wide-Field Infrared Survey Explorer Mission

NASA Technical Reports Server (NTRS)

Irace, William; Cutri, Roc; Duval, Valerie; Eisenhardt, Peter; Elwell, John; Greanias, George; Heinrichsen, Ingolf; Howard, Joan; Liu, Feng-Chuan; Royer, Donald;

Wide-field three-photon excitation in biological samples

PubMed Central

Rowlands, Christopher J; Park, Demian; Bruns, Oliver T; Piatkevich, Kiryl D; Fukumura, Dai; Jain, Rakesh K; Bawendi, Moungi G; Boyden, Edward S; So, Peter TC

2017-01-01

Three-photon wide-field depth-resolved excitation is used to overcome some of the limitations in conventional point-scanning two- and three-photon microscopy. Excitation of chromophores as diverse as channelrhodopsins and quantum dots is shown, and a penetration depth of more than 700 μm into fixed scattering brain tissue is achieved, approximately twice as deep as that achieved using two-photon wide-field excitation. Compatibility with live animal experiments is confirmed by imaging the cerebral vasculature of an anesthetized mouse; a complete focal stack was obtained without any evidence of photodamage. As an additional validation of the utility of wide-field three-photon excitation, functional excitation is demonstrated by performing three-photon optogenetic stimulation of cultured mouse hippocampal neurons expressing a channelrhodopsin; action potentials could reliably be excited without causing photodamage. PMID:29152380

Near-infrared hyperspectral imaging for detecting Aflatoxin B1 of maize kernels

USDA-ARS?s Scientific Manuscript database

The feasibility of detecting the Aflatoxin B1 in maize kernels inoculated with Aspergillus flavus conidia in the field was assessed using near-infrared hyperspectral imaging technique. After pixel-level calibration, wavelength dependent offset, the masking method was adopted to reduce the noise and ...

POLICAN: A near-infrared imaging polarimeter at OAGH

NASA Astrophysics Data System (ADS)

Devaraj, R.; Luna, A.; Carrasco, L.; Mayya, Y. D.; Serrano-Bernal, O.

2017-07-01

We present a near-infrared linear imaging polarimeter POLICAN, 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. POLICAN reaches a limiting magnitude to about 16th mag with a polarimetric accuracy of about 1% for bright sources.

Solar-wind proton access deep into the near-Moon wake

NASA Astrophysics Data System (ADS)

Nishino, M. N.; Fujimoto, M.; Maezawa, K.; Saito, Y.; Yokota, S.; Asamura, K.; Tanaka, T.; Tsunakawa, H.; Matsushima, M.; Takahashi, F.; Terasawa, T.; Shibuya, H.; Shimizu, H.

2009-08-01

We study solar wind (SW) entry deep into the near-Moon wake using SELENE (KAGUYA) data. It has been known that SW protons flowing around the Moon access the central region of the distant lunar wake, while their intrusion deep into the near-Moon wake has never been expected. We show that SW protons sneak into the deepest lunar wake (anti-subsolar region at ˜100 km altitude), and that the entry yields strong asymmetry of the near-Moon wake environment. Particle trajectory calculations demonstrate that these SW protons are once scattered at the lunar dayside surface, picked-up by the SW motional electric field, and finally sneak into the deepest wake. Our results mean that the SW protons scattered at the lunar dayside surface and coming into the night side region are crucial for plasma environment in the wake, suggesting absorption of ambient SW electrons into the wake to maintain quasi-neutrality.

MOIRCS Deep Survey. I: DRG Number Counts

NASA Astrophysics Data System (ADS)

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

2006-12-01

We use very deep near-infrared imaging data taken with Multi-Object InfraRed Camera and Spectrograph (MOIRCS) on the Subaru Telescope to investigate the number counts of Distant Red Galaxies (DRGs). We have observed a 4x7 arcmin^2 field in the Great Observatories Origins Deep Survey North (GOODS-N), and our data reach J=24.6 and K=23.2 (5sigma, Vega magnitude). The surface density of DRGs selected by J-K>2.3 is 2.35+-0.31 arcmin^-2 at K<22 and 3.54+-0.38 arcmin^-2 at K<23, respectively. These values are consistent with those in the GOODS-South and FIRES. Our deep and wide data suggest that the number counts of DRGs turn over at K~22, and the surface density of the faint DRGs with K>22 is smaller than that expected from the number counts at the brighter magnitude. The result indicates that while there are many bright galaxies at 222 suggest that the mass-dependent color distribution, where most of low-mass galaxies are blue while more massive galaxies tend to have redder colors, had already been established at that epoch.

Slitless spectroscopy with the James Webb Space Telescope Near-Infrared Camera (JWST NIRCam)

NASA Astrophysics Data System (ADS)

Greene, Thomas P.; Chu, Laurie; Egami, Eiichi; Hodapp, Klaus W.; Kelly, Douglas M.; Leisenring, Jarron; Rieke, Marcia; Robberto, Massimo; Schlawin, Everett; Stansberry, John

2016-07-01

The James Webb Space Telescope near-infrared camera (JWST NIRCam) has two 2.02 x 2.02 fields of view that are capable of either imaging or spectroscopic observations. Either of two R ~ 1500 grisms with orthogonal dispersion directions can be used for slitless spectroscopy over λ = 2.4 - 5.0 μm in each module, and shorter wavelength observations of the same fields can be obtained simultaneously. We present the latest predicted grism sensitivities, saturation limits, resolving power, and wavelength coverage values based on component measurements, instrument tests, and end-to-end modeling. Short wavelength (0.6 - 2.3 μm) imaging observations of the 2.4 - 5.0 μm spectroscopic field can be performed in one of several different filter bands, either in-focus or defocused via weak lenses internal to NIRCam. Alternatively, the possibility of 1.0 - 2.0 μm spectroscopy (simultaneously with 2.4 - 5.0 μm) using dispersed Hartmann sensors (DHSs) is being explored. The grisms, weak lenses, and DHS elements were included in NIRCam primarily for wavefront sensing purposes, but all have significant science applications. Operational considerations including subarray sizes, and data volume limits are also discussed. Finally, we describe spectral simulation tools and illustrate potential scientific uses of the grisms by presenting simulated observations of deep extragalactic fields, galactic dark clouds, and transiting exoplanets.

Laser heating of scanning probe tips for thermal near-field spectroscopy and imaging

NASA Astrophysics Data System (ADS)

O'Callahan, Brian T.; Raschke, Markus B.

2017-02-01

Spectroscopy and microscopy of the thermal near-field yield valuable insight into the mechanisms of resonant near-field heat transfer and Casimir and Casimir-Polder forces, as well as providing nanoscale spatial resolution for infrared vibrational spectroscopy. A heated scanning probe tip brought close to a sample surface can excite and probe the thermal near-field. Typically, tip temperature control is provided by resistive heating of the tip cantilever. However, this requires specialized tips with limited temperature range and temporal response. By focusing laser radiation onto AFM cantilevers, we achieve heating up to ˜1800 K, with millisecond thermal response time. We demonstrate application to thermal infrared near-field spectroscopy (TINS) by acquiring near-field spectra of the vibrational resonances of silicon carbide, hexagonal boron nitride, and polytetrafluoroethylene. We discuss the thermal response as a function of the incident excitation laser power and model the dominant cooling contributions. Our results provide a basis for laser heating as a viable approach for TINS, nanoscale thermal transport measurements, and thermal desorption nano-spectroscopy.

Upconversion fiber-optic confocal microscopy under near-infrared pumping.

PubMed

Kim, Do-Hyun; Kang, Jin U; Ilev, Ilko K

2008-03-01

We present a simple upconversion fiber-optic confocal microscope design using a near-infrared laser for pumping of a rare-earth-doped glass powder. The nonlinear optical frequency conversion process is highly efficient with more than 2% upconversion fluorescence efficiency at a near-infrared pumping wavelength of 1.55 microm. The upconversion confocal design allows the use of conventional Si detectors and 1.55 microm near-infrared pump light. The lateral and axial resolutions of the system were equal to or better than 1.10 and 13.11 microm, respectively.

GEMINI NEAR INFRARED FIELD SPECTROGRAPH OBSERVATIONS OF THE SEYFERT 2 GALAXY MRK 573: IN SITU ACCELERATION OF IONIZED AND MOLECULAR GAS OFF FUELING FLOWS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, Travis C.; Straughn, A. N.; Machuca, C.

2017-01-01

We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in a ∼700 × 2100 pc{sup 2} circumnuclear region of Mrk 573, we find that kinematics within the Narrow-Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out tomore » several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.« less

Gemini Near Infrared Field Spectrograph Observations of the Seyfert 2 Galaxy MRK 573: In Situ Acceleration of Ionized and Molecular Gas Off Fueling Flows

NASA Technical Reports Server (NTRS)

Fischer, Travis C.; Machuca, C.; Diniz, M. R.; Crenshaw, D. M.; Kraemer, S. B.; Riffel, R. A.; Schmitt, H. R.; Baron, F.; Storchi-Bergmann, T.; Straughn, A. N.;

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 controls...

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 controls...

Energy Transfer Highway in Nd3+-Sensitized Nanoparticles for Efficient near-Infrared Bioimaging.

PubMed

Cao, Cong; Xue, Meng; Zhu, Xingjun; Yang, Pengyuan; Feng, Wei; Li, Fuyou

2017-06-07

Despite the large absorption cross-section of Nd 3+ dopant as a sensitizer in lanthanide doped luminescence system, the strong cross-relaxation effect of it impedes the promotion of doping concentration and thus reduces the utilization of excitation light. In this work, we introduce a highly efficient acceptor, Yb 3+ ion, which can quickly receive energy from Nd 3+ ions, to construct an energy transfer highway for the enhancement of near-infrared emission. By using the energy transfer highway, the doping amount of Nd 3+ ions in our NaYF 4 :Yb,Nd@CaF 2 core/shell nanoparticles (CSNPs) can be markedly elevated to 60%. The quantum yield of CSNPs was determined to be 20.7%, which provides strong near-infrared luminescence for further bioimaging application. Remarkably, deep tissue penetration depth (∼10 mm) in in vitro imaging and high spatial resolution of blood vessel (∼0.19 mm) in in vivo imaging were detected clearly with weak autofluorescence, demonstrating that probes can be used as excellent NIR biosensors.

Properties of Dust Obscured Galaxies in the Nep-Deep Field

NASA Astrophysics Data System (ADS)

Oi, Nagisa; Matsuhara, Hideo; Pearson, Chris; Buat, Veronique; Burgarella, Denis; Malkan, Matt; Miyaji, Takamitsu; AKARI-NEP Team

2017-03-01

We selected 47 DOGs at z∼1.5 using optical R (or r^{'}), AKARI 18 μm, and 24 μm color in the AKARI North Ecliptic Pole (NEP) Deep survey field. Using the colors among 3, 4, 7, and 9μm, we classified them into 3 groups; bump DOGs (23 sources), power-law DOGs (16 sources), and unknown DOGs (8 sources). We built spectral energy distributions (SEDs) with optical to far-infrared photometric data and investigated their properties using SED fitting method. We found that AGN activity such as a AGN contribution to the infrared luminosity and a Chandra detection rate for bump and power-law DOGs are significantly different, while stellar component properties like a stellar mass and a star-formation rate are similar to each other. A specific star-formation rate range of power-law DOGs is slightly higher than that of bump DOGs with wide overlap. Herschel/PACS detection rates are almost the same between bump and power-law DOGs. On the other hand SPIRE detection rates show large differences between bump and power-law DOGs. These results might be explained by differences in dust temperatures. Both groups of DOGs host hot and/or warm dust (∼ 50 Kelvin), and many bump DOGs contain cooler dust (≤ 30 Kelvin)

Micro-electro-mechanically switchable near infrared complementary metamaterial absorber

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitchappa, Prakash; Pei Ho, Chong; Institute of Microelectronics

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 μmmore » 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.« less

Soil texture and organic carbon fractions predicted from near-infrared spectroscopy and geostatistics

USDA-ARS?s Scientific Manuscript database

Field-specific management could help achieve agricultural sustainability by increasing production and decreasing environmental impacts. Near-infrared spectroscopy (NIRS) and geostatistics are relatively unexplored tools that could reduce time, labor, and costs of soil analysis. Our objective was to ...

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.

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.

Preliminary comparisons of portable near infrared (nir) instrumentation for laboratory measurements of cotton fiber micronaire

USDA-ARS?s Scientific Manuscript database

Micronaire is a key quality and processing parameter for cotton fiber. A program was implemented to determine the capabilities of portable Near Infrared (NIR) instrumentation to monitor cotton fiber micronaire both in the laboratory and in/near the field. Previous evaluations on one NIR unit demon...

Discovery of two new Galactic candidate luminous blue variables with Wide-field Infrared Survey Explorer

NASA Astrophysics Data System (ADS)

Gvaramadze, V. V.; Kniazev, A. Y.; Miroshnichenko, A. S.; Berdnikov, L. N.; Langer, N.; Stringfellow, G. S.; Todt, H.; Hamann, W.-R.; Grebel, E. K.; Buckley, D.; Crause, L.; Crawford, S.; Gulbis, A.; Hettlage, C.; Hooper, E.; Husser, T.-O.; Kotze, P.; Loaring, N.; Nordsieck, K. H.; O'Donoghue, D.; Pickering, T.; Potter, S.; Romero Colmenero, E.; Vaisanen, P.; Williams, T.; Wolf, M.; Reichart, D. E.; Ivarsen, K. M.; Haislip, J. B.; Nysewander, M. C.; LaCluyze, A. P.

2012-04-01

We report the discovery of two new Galactic candidate luminous blue variable (LBV) stars via detection of circular shells (typical of confirmed and candidate LBVs) and follow-up spectroscopy of their central stars. The shells were detected at 22 μm in the archival data of the Mid-Infrared All Sky Survey carried out with the Wide-field Infrared Survey Explorer (WISE). Follow-up optical spectroscopy of the central stars of the shells conducted with the renewed Southern African Large Telescope (SALT) showed that their spectra are very similar to those of the well-known LBVs P Cygni and AG Car, and the recently discovered candidate LBV MN112, which implies the LBV classification for these stars as well. The LBV classification of both stars is supported by detection of their significant photometric variability: one of them brightened in the R and I bands by 0.68 ± 0.10 and 0.61 ± 0.04 mag, respectively, during the last 13-18 years, while the second one (known as Hen 3-1383) varies its B, V, R, I and Ks brightnesses by ≃0.5-0.9 mag on time-scales from 10 d to decades. We also found significant changes in the spectrum of Hen 3-1383 on a time-scale of ≃3 months, which provides additional support for the LBV classification of this star. Further spectrophotometric monitoring of both stars is required to firmly prove their LBV status. We discuss a connection between the location of massive stars in the field and their fast rotation, and suggest that the LBV activity of the newly discovered candidate LBVs might be directly related to their possible runaway status. a USNO B-1 (Monet et al. 2003); bDENIS; c2MASS; dSALT; ePROMPT.

Estimating the marine signal in the near infrared for atmospheric correction of satellite ocean-color imagery over turbid waters

NASA Astrophysics Data System (ADS)

Bourdet, Alice; Frouin, Robert J.

2014-11-01

The classic atmospheric correction algorithm, routinely applied to second-generation ocean-color sensors such as SeaWiFS, MODIS, and MERIS, consists of (i) estimating the aerosol reflectance in the red and near infrared (NIR) where the ocean is considered black (i.e., totally absorbing), and (ii) extrapolating the estimated aerosol reflectance to shorter wavelengths. The marine reflectance is then retrieved by subtraction. Variants and improvements have been made over the years to deal with non-null reflectance in the red and near infrared, a general situation in estuaries and the coastal zone, but the solutions proposed so far still suffer some limitations, due to uncertainties in marine reflectance modeling in the near infrared or difficulty to extrapolate the aerosol signal to the blue when using observations in the shortwave infrared (SWIR), a spectral range far from the ocean-color wavelengths. To estimate the marine signal (i.e., the product of marine reflectance and atmospheric transmittance) in the near infrared, the proposed approach is to decompose the aerosol reflectance in the near infrared to shortwave infrared into principal components. Since aerosol scattering is smooth spectrally, a few components are generally sufficient to represent the perturbing signal, i.e., the aerosol reflectance in the near infrared can be determined from measurements in the shortwave infrared where the ocean is black. This gives access to the marine signal in the near infrared, which can then be used in the classic atmospheric correction algorithm. The methodology is evaluated theoretically from simulations of the top-of-atmosphere reflectance for a wide range of geophysical conditions and angular geometries and applied to actual MODIS imagery acquired over the Gulf of Mexico. The number of discarded pixels is reduced by over 80% using the PC modeling to determine the marine signal in the near infrared prior to applying the classic atmospheric correction algorithm.

Topological Crystalline Insulator SnTe/Si Vertical Heterostructure Photodetectors for High-Performance Near-Infrared Detection.

PubMed

Zhang, Hongbin; Man, Baoyuan; Zhang, Qi

2017-04-26

Due to the gapless surface state and narrow bulk band gap, the light absorption of topological crystalline insulators covers a broad spectrum ranging from terahertz to infrared, revealing promising applications in new generation optoelectronic devices. To date, the photodetectors based on topological insulators generally suffer from a large dark current and a weaker photocurrent especially under the near-infrared lights, which severely limits the practical application of devices. Owing to the lower excitation energy of infrared lights, the photodetection application of topological crystalline insulators in the near-infrared region relies critically on understanding the preparation and properties of their heterostructures. Herein, we fabricate the high-quality topological crystalline insulator SnTe film/Si vertical heterostructure by a simple physical vapor deposition process. The resultant heterostructure exhibits an excellent diode characteristic, enabling the construction of high-performance near-infrared photodetectors. The built-in electric field at SnTe/Si interface enhances the absorption efficiency of near-infrared lights and greatly facilitates the separation of photogenerated carriers, making the device capable of operating as a self-driven photodetector. The as-grown SnTe film acts as the hole transport layer in heterostructure photodetectors, promoting the transport of holes to electrode and reducing electron-hole recombination effectively. These merits enable the SnTe/Si heterostructure photodetector to have a high responsivity of 2.36 AW -1 , a high detectivity of 1.54 × 10 14 Jones, and a large bandwidth of 10 4 Hz in the near-infrared wavelength, which makes the detector have a promising market in novel device applications.

Tunable near- to mid-infrared pump terahertz probe spectroscopy in reflection geometry

NASA Astrophysics Data System (ADS)

Zhang, S. J.; Wang, Z. X.; Dong, T.; Wang, N. L.

2017-10-01

Strong-field mid-infrared pump-terahertz (THz) probe spectroscopy has been proven as a powerful tool for light control of different orders in strongly correlated materials. We report the construction of an ultrafast broadband infrared pump-THz probe system in reflection geometry. A two-output optical parametric amplifier is used for generating mid-infrared pulses with GaSe as the nonlinear crystal. The setup is capable of pumping bulk materials at wavelengths ranging from 1.2 μm to 15 μm and beyond, and detecting the subtle, transient photoinduced changes in the reflected electric field of the THz probe at different temperatures. As a demonstration, we present 15 μm pump-THz probe measurements of a bulk EuSbTe3 single crystal. A 0:5% transient change in the reflected THz electric field can be clearly resolved. The widely tuned pumping energy could be used in mode-selective excitation experiments and applied to many strongly correlated electron systems.

Hyperspectral infrared nanoimaging of organic samples based on Fourier transform infrared nanospectroscopy

PubMed Central

Amenabar, Iban; Poly, Simon; Goikoetxea, Monika; Nuansing, Wiwat; Lasch, Peter; Hillenbrand, Rainer

2017-01-01

Infrared nanospectroscopy enables novel possibilities for chemical and structural analysis of nanocomposites, biomaterials or optoelectronic devices. Here we introduce hyperspectral infrared nanoimaging based on Fourier transform infrared nanospectroscopy with a tunable bandwidth-limited laser continuum. We describe the technical implementations and present hyperspectral infrared near-field images of about 5,000 pixel, each one covering the spectral range from 1,000 to 1,900 cm−1. To verify the technique and to demonstrate its application potential, we imaged a three-component polymer blend and a melanin granule in a human hair cross-section, and demonstrate that multivariate data analysis can be applied for extracting spatially resolved chemical information. Particularly, we demonstrate that distribution and chemical interaction between the polymer components can be mapped with a spatial resolution of about 30 nm. We foresee wide application potential of hyperspectral infrared nanoimaging for valuable chemical materials characterization and quality control in various fields ranging from materials sciences to biomedicine. PMID:28198384

Hyperspectral infrared nanoimaging of organic samples based on Fourier transform infrared nanospectroscopy

NASA Astrophysics Data System (ADS)

Amenabar, Iban; Poly, Simon; Goikoetxea, Monika; Nuansing, Wiwat; Lasch, Peter; Hillenbrand, Rainer

2017-02-01

Infrared nanospectroscopy enables novel possibilities for chemical and structural analysis of nanocomposites, biomaterials or optoelectronic devices. Here we introduce hyperspectral infrared nanoimaging based on Fourier transform infrared nanospectroscopy with a tunable bandwidth-limited laser continuum. We describe the technical implementations and present hyperspectral infrared near-field images of about 5,000 pixel, each one covering the spectral range from 1,000 to 1,900 cm-1. To verify the technique and to demonstrate its application potential, we imaged a three-component polymer blend and a melanin granule in a human hair cross-section, and demonstrate that multivariate data analysis can be applied for extracting spatially resolved chemical information. Particularly, we demonstrate that distribution and chemical interaction between the polymer components can be mapped with a spatial resolution of about 30 nm. We foresee wide application potential of hyperspectral infrared nanoimaging for valuable chemical materials characterization and quality control in various fields ranging from materials sciences to biomedicine.

Engineering Near-Field Transport of Energy using Nanostructured Materials

DTIC Science & Technology

2015-12-12

increasingly important for a wide range of nanotechnology applications. Recent computational studies on near- field radiative heat transfer (NFRHT) suggest...SECURITY CLASSIFICATION OF: The transport of heat at the nanometer scale is becoming increasingly important for a wide range of nanotechnology...applications. Recent computational studies on near- field radiative heat transfer (NFRHT) suggest that radiative energy transport between suitably chosen

VizieR Online Data Catalog: Low-resolution near-infrared stellar spectra from CIBER (Kim+, 2017)

NASA Astrophysics Data System (ADS)

Kim, M. G.; Lee, H. M.; Arai, T.; Bock, J.; Cooray, A.; Jeong, W.-S.; Kim, S. J.; Korngut, P.; Lanz, A.; Lee, D. H.; Lee, M. G.; Matsumoto, T.; Matsuura, S.; Nam, U. W.; Onishi, Y.; Shirahata, M.; Smidt, J.; Tsumura, K.; Yamamura, I.; Zemcov, M.

2017-06-01

We present flux-calibrated near-infrared spectra of 105 stars from 0.8{<=}λ{<=}1.8μm with spectral resolution 15{<=}λ/Δλ{<=}30 over the range. The Low-Resolution Spectrometer (LRS) is one of the four optical instruments of the Cosmic Infrared Background Experiment (CIBER) payload; the others are a narrowband spectrometer and two wide-field imagers. The LRS is a prism-dispersed spectrometer with five rectangular 5.35°*2.8' slits imaging a 5.8°*5.8° field of view. The detector has 256*256 pixels at a pixel scale of 1.36'*1.36'. CIBER has flown four times (2009 February, 2010 July, 2012 March, and 2013 June) with apogees and total exposure times of over 325km and ~240s, respectively, in the first three flights and of 550km and 335s in the final, non-recovered flight. Due to spurious signal contamination from thermal emission from the shock-heated rocket skin, we do not use the first flight data in this work. The star spectral types are determined by fitting known spectral templates to the measured LRS spectra. We use the Infrared Telescope Facility (IRTF) and Pickles 1998 (Cat. J/PASP/110/863) templates for the SED fitting. The SpeX instrument installed on the IRTF observed stars using a medium-resolution spectrograph (R=2000). The template library contains spectra for 210 cool stars (F to M type) with wavelength coverage from 0.8 to 2.5μm (Cushing 2005ApJ...623.1115C; Rayner 2009ApJS..185..289R). The Pickles library is a synthetic spectral library that combines spectral data from various observations to achieve wavelength coverage from the UV (0.115μm) to the near-infrared (2.5μm). It contains 131 spectral templates for all star types (i.e., O to M type) with a uniform sampling interval of 5Å. (6 data files).

A LABOCA Survey of the Extended Chandra Deep Field South—Submillimeter Properties of Near-infrared Selected Galaxies

NASA Astrophysics Data System (ADS)

Greve, T. R.; Weiβ, A.; Walter, F.; Smail, I.; Zheng, X. Z.; Knudsen, K. K.; Coppin, K. E. K.; Kovács, A.; Bell, E. F.; de Breuck, C.; Dannerbauer, H.; Dickinson, M.; Gawiser, E.; Lutz, D.; Rix, H.-W.; Schinnerer, E.; Alexander, D.; Bertoldi, F.; Brandt, N.; Chapman, S. C.; Ivison, R. J.; Koekemoer, A. M.; Kreysa, E.; Kurczynski, P.; Menten, K.; Siringo, G.; Swinbank, M.; van der Werf, P.

2010-08-01

Using the 330 hr ESO-MPG 870 μm survey of the Extended Chandra Deep Field South (ECDF-S) obtained with the Large Apex BOlometer CAmera (LABOCA) on the Atacama Pathfinder EXperiment (APEX), we have carried out a stacking analysis at submillimeter (submm) wavelengths of a sample of 8266 near-infra-red (near-IR) selected (K vega <= 20) galaxies, including 893 BzK galaxies, 1253 extremely red objects (EROs), and 737 distant red galaxies (DRGs), selected from the Multi-wavelength Survey by Yale-Chile (MUSYC). We measure average 870 μm fluxes of 0.22 ± 0.01 mJy (22.0σ), 0.48 ± 0.04 mJy (12.0σ), 0.39 ± 0.03 mJy (13.0σ), and 0.43 ± 0.04 mJy (10.8σ) for the K vega <= 20, BzK, ERO, and DRG samples, respectively. For the BzK, ERO, and DRG sub-samples, which overlap to some degree and are likely to be at z ~= 1-2, this implies an average far-IR luminosity of ~(1-5) × 1011 Lsun and star formation rate (SFR) of ~20-90 Msun . Splitting the BzK galaxies into star-forming (sBzK) and passive (pBzK) galaxies, the former is significantly detected (0.50 ± 0.04 mJy, 12.5σ) while the latter is only marginally detected (0.34 ± 0.10 mJy, 3.4σ), thus confirming that the sBzK and pBzK criteria to some extent select obscured, star-forming, and truly passive galaxies, respectively. The K vega <= 20 galaxies are found to contribute 7.27 ± 0.34 Jy deg-2 (16.5% ± 5.7%) to the 870 μm extragalactic background light (EBL). sBzK and pBzK galaxies contribute 1.49 ± 0.22 Jy deg-2 (3.4% ± 1.3%) and 0.20 ± 0.14 Jy deg-2 (0.5% ± 0.3%) to the EBL. We present the first delineation of the average submm signal from the K vega <= 20 selected galaxies and their contribution to the submm EBL as a function of (photometric) redshift, and find a decline in the average submm signal (and therefore IR luminosity and SFR) by a factor ~2-3 from z ~ 2 to z ~ 0. This is in line with a cosmic star formation history in which the star formation activity in galaxies increases significantly at z >~ 1. A

Review of functional near-infrared spectroscopy in neurorehabilitation

PubMed Central

Mihara, Masahito; Miyai, Ichiro

2016-01-01

Abstract. We provide a brief overview of the research and clinical applications of near-infrared spectroscopy (NIRS) in the neurorehabilitation field. NIRS has several potential advantages and shortcomings as a neuroimaging tool and is suitable for research application in the rehabilitation field. As one of the main applications of NIRS, we discuss its application as a monitoring tool, including investigating the neural mechanism of functional recovery after brain damage and investigating the neural mechanisms for controlling bipedal locomotion and postural balance in humans. In addition to being a monitoring tool, advances in signal processing techniques allow us to use NIRS as a therapeutic tool in this field. With a brief summary of recent studies investigating the clinical application of NIRS using motor imagery task, we discuss the possible clinical usage of NIRS in brain–computer interface and neurofeedback. PMID:27429995

THE MAGNETIC FIELD OF L1544. I. NEAR-INFRARED POLARIMETRY AND THE NON-UNIFORM ENVELOPE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clemens, Dan P.; Tassis, K.; Goldsmith, Paul F., E-mail: clemens@bu.edu, E-mail: tassis@physics.uoc.gr, E-mail: paul.f.goldsmith@jpl.nasa.gov

2016-12-20

The magnetic field ( B -field) of the starless dark cloud L1544 has been studied using near-infrared (NIR) background starlight polarimetry (BSP) and archival data in order to characterize the properties of the plane-of-sky B -field. NIR linear polarization measurements of over 1700 stars were obtained in the H band and 201 of these were also measured in the K band. The NIR BSP properties are correlated with reddening, as traced using the Rayleigh–Jeans color excess ( H – M ) method, and with thermal dust emission from the L1544 cloud and envelope seen in Herschel maps. The NIR polarizationmore » position angles change at the location of the cloud and exhibit their lowest dispersion there, offering strong evidence that NIR polarization traces the plane-of-sky B -field of L1544. In this paper, the uniformity of the plane-of-sky B -field in the envelope region of L1544 is quantitatively assessed. This allows evaluation of the approach of assuming uniform field geometry when measuring relative mass-to-flux ratios in the cloud envelope and core based on averaging of the radio Zeeman observations in the envelope, as done by Crutcher et al. In L1544, the NIR BSP shows the envelope B -field to be significantly non-uniform and likely not suitable for averaging Zeeman properties without treating intrinsic variations. Deeper analyses of the NIR BSP and related data sets, including estimates of the B -field strength and testing how it varies with position and gas density, are the subjects of later papers in this series.« less

[Applications of near infrared reflectance spectroscopy in detecting chitin, ergosterol and mycotoxins].

PubMed

Yi, Yong-Yan; Li, De-Rong; Zhang, Yun-Wei; Yang, Fu-Yu

2009-07-01

The invasion extent and harmfulness of fungi can be determined by chitin, ergosterol and mycotoxins. It is important to monitor chitin, ergosterol and mycotoxins changes to prevent contamination of forage and feed products, and effectively control the sustainable development of the mildew. Predication of these chemical materials was often completed by laboratory analysis, which was time-consuming and cumbersome and could not reflect the results in time in the past. Near infrared reflectance spectroscopy (NIRS) is a rapid, convenient, highly efficient, nondestructive and low-cost analytical technique, which has been widely used in various fields such as food field and feed field for quantitative and qualitative analysis. It has a great potentiality of application in quality analysis. In this paper, the principle and the characteristic of NIRS and its applications in food, forage, feed and other agriculture products quality analysis were introduced. Its applications in fungal biomass (chitin, ergosterol) and mycotoxins were mainly reviewed. NIRS was used to quantify chitin, ergosterol and mycotoxins. Calibration equations and validation equations for these materials were developed. It is also expected that NIRS will play a more and more important role in the field of fungi with the establishment of calibration equation and improvement of model database.

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.

Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization

DTIC Science & Technology

2012-09-01

Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization by Justin R. Bickford, Neal K. Bambha, and Wayne H. Chang...Adelphi, MD 20783-1197 ARL-TR-6169 September 2012 Near-room-temperature Mid-infrared Photoconductor Signal and Noise Characterization...temperature Mid-infrared Photoconductor Signal and Noise Characterization 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

Near-infrared autofluorescence imaging to detect parathyroid glands in thyroid surgery.

PubMed

Ladurner, R; Al Arabi, N; Guendogar, U; Hallfeldt, Kkj; Stepp, H; Gallwas, Jks

2018-01-01

Objective To identify and save parathyroid glands during thyroidectomy by displaying their autofluorescence. Methods Autofluorescence imaging was carried out during thyroidectomy with and without central lymph node dissection. After visual recognition by the surgeon, the parathyroid glands and the surrounding tissue were exposed to near-infrared light with a wavelength of 690-770 nm using a modified Karl Storz near infrared/indocyanine green endoscopic system. Parathyroid tissue was expected to show near infrared autofluorescence at 820 nm, captured in the blue channel of the camera. Results We investigated 41 parathyroid glands from 20 patients; 37 glands were identified correctly based on near-infrared autofluorescence. Neither lymph nodes nor thyroid revealed substantial autofluorescence and nor did adipose tissue. Conclusions Parathyroid tissue is characterised by showing autofluorescence in the near-infrared spectrum. This effect can be used to identify and preserve parathyroid glands during thyroidectomy.

NIRCam: Development and Testing of the JWST Near-Infrared Camera

NASA Technical Reports Server (NTRS)

Greene, Thomas; Beichman, Charles; Gully-Santiago, Michael; Jaffe, Daniel; Kelly, Douglas; Krist, John; Rieke, Marcia; Smith, Eric H.

2011-01-01

The Near Infrared Camera (NIRCam) is one of the four science instruments of the James Webb Space Telescope (JWST). Its high sensitivity, high spatial resolution images over the 0.6 - 5 microns wavelength region will be essential for making significant findings in many science areas as well as for aligning the JWST primary mirror segments and telescope. The NIRCam engineering test unit was recently assembled and has undergone successful cryogenic testing. The NIRCam collimator and camera optics and their mountings are also progressing, with a brass-board system demonstrating relatively low wavefront error across a wide field of view. The flight model?s long-wavelength Si grisms have been fabricated, and its coronagraph masks are now being made. Both the short (0.6 - 2.3 microns) and long (2.4 - 5.0 microns) wavelength flight detectors show good performance and are undergoing final assembly and testing. The flight model subsystems should all be completed later this year through early 2011, and NIRCam will be cryogenically tested in the first half of 2011 before delivery to the JWST integrated science instrument module (ISIM).

Raman, mid-infrared, near-infrared and ultraviolet-visible spectroscopy of PDMS silicone rubber for characterization of polymer optical waveguide materials

NASA Astrophysics Data System (ADS)

Cai, Dengke; Neyer, Andreas; Kuckuk, Rüdiger; Heise, H. Michael

2010-07-01

Special siloxane polymers have been produced via an addition reaction from commercially available two-component addition materials by thermal curing. Polydimethylsiloxane (PDMS) based polymers have already been used in the optical communication field, where passive polymer multimode waveguides are required for short-distance datacom optical applications. For such purpose, materials with low intrinsic absorption losses within the spectral region of 600-900 nm wavelengths are essential. For vibrational absorption band assignments, especially in the visible and short-wave near-infrared region, the mid-infrared and Raman spectra were investigated for fundamental vibrations of the siloxane materials, shedding light onto the chemistry before and after material polymerization. Within the near-infrared and long-wave visible spectral range, vibrational C sbnd H stretching overtone and combination bands dominate the spectra, rendering an optical characterization of core and clad materials. Such knowledge also provides information for the synthesis and optical characterization, e.g., of deuterated derivatives with less intrinsic absorption losses from molecular vibrations compared to the siloxane materials studied.

Topology optimized gold nanostrips for enhanced near-infrared photon upconversion

NASA Astrophysics Data System (ADS)

Vester-Petersen, Joakim; Christiansen, Rasmus E.; Julsgaard, Brian; Balling, Peter; Sigmund, Ole; Madsen, Søren P.

2017-09-01

This letter presents a topology optimization study of metal nanostructures optimized for electric-field enhancement in the infrared spectrum. Coupling of such nanostructures with suitable ions allows for an increased photon-upconversion yield, with one application being an increased solar-cell efficiency by exploiting the long-wavelength part of the solar spectrum. In this work, topology optimization is used to design a periodic array of two-dimensional gold nanostrips for electric-field enhancements in a thin film doped with upconverting erbium ions. The infrared absorption band of erbium is utilized by simultaneously optimizing for two polarizations, up to three wavelengths, and three incident angles. Geometric robustness towards manufacturing variations is implemented considering three different design realizations simultaneously in the optimization. The polarization-averaged field enhancement for each design is evaluated over an 80 nm wavelength range and a ±15-degree incident angle span. The highest polarization-averaged field enhancement is 42.2 varying by maximally 2% under ±5 nm near-uniform design perturbations at three different wavelengths (1480 nm, 1520 nm, and 1560 nm). The proposed method is generally applicable to many optical systems and is therefore not limited to enhancing photon upconversion.

HFF-DeepSpace Photometric Catalogs of the 12 Hubble Frontier Fields, Clusters, and Parallels: Photometry, Photometric Redshifts, and Stellar Masses

NASA Astrophysics Data System (ADS)

Shipley, Heath V.; Lange-Vagle, Daniel; Marchesini, Danilo; Brammer, Gabriel B.; Ferrarese, Laura; Stefanon, Mauro; Kado-Fong, Erin; Whitaker, Katherine E.; Oesch, Pascal A.; Feinstein, Adina D.; Labbé, Ivo; Lundgren, Britt; Martis, Nicholas; Muzzin, Adam; Nedkova, Kalina; Skelton, Rosalind; van der Wel, Arjen

2018-03-01

We present Hubble multi-wavelength photometric catalogs, including (up to) 17 filters with the Advanced Camera for Surveys and Wide Field Camera 3 from the ultra-violet to near-infrared for the Hubble Frontier Fields and associated parallels. We have constructed homogeneous photometric catalogs for all six clusters and their parallels. To further expand these data catalogs, we have added ultra-deep K S -band imaging at 2.2 μm from the Very Large Telescope HAWK-I and Keck-I MOSFIRE instruments. We also add post-cryogenic Spitzer imaging at 3.6 and 4.5 μm with the Infrared Array Camera (IRAC), as well as archival IRAC 5.8 and 8.0 μm imaging when available. We introduce the public release of the multi-wavelength (0.2–8 μm) photometric catalogs, and we describe the unique steps applied for the construction of these catalogs. Particular emphasis is given to the source detection band, the contamination of light from the bright cluster galaxies (bCGs), and intra-cluster light (ICL). In addition to the photometric catalogs, we provide catalogs of photometric redshifts and stellar population properties. Furthermore, this includes all the images used in the construction of the catalogs, including the combined models of bCGs and ICL, the residual images, segmentation maps, and more. These catalogs are a robust data set of the Hubble Frontier Fields and will be an important aid in designing future surveys, as well as planning follow-up programs with current and future observatories to answer key questions remaining about first light, reionization, the assembly of galaxies, and many more topics, most notably by identifying high-redshift sources to target.

Spot fat reduction by red and near infrared LED phototherapy

NASA Astrophysics Data System (ADS)

Lim, Sungkyoo; Park, Eal-Whan

2018-02-01

Low level light therapy (LLLT) using light from red and near infrared LEDs or Lasers have been reported effective as noninvasive methods for reducing spot fat. A total of 55 subjects were randomly divided into test groups and control groups for abdominal fat reduction clinical trial using red and near infrared LED phototherapy devices. Red and near infrared light with irradiance of 10 mW/cm2 were irradiated over the abdominal area to the test group for 30 minutes followed by 30 minutes of aerobic exercise, 3 times a week for 4 weeks. Control group used sham devices for 30 minutes and followed by 30 minutes of aerobic exercise. It is expected that red and near infrared LED phototherapy combined with aerobic exercise would be effective and safe for abdominal fat reduction without any side effects.

Near-infrared photodetectors utilizing MoS{sub 2}-based heterojunctions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Min Ji; Min, Jung Ki; Yi, Sum-Gyun

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.

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.

Transcranial Red and Near Infrared Light Transmission in a Cadaveric Model

PubMed Central

Jagdeo, Jared R.; Adams, Lauren E.; Brody, Neil I.; Siegel, Daniel M.

2012-01-01

Background and Objective Low level light therapy has garnered significant interest within the past decade. The exact molecular mechanisms of how red and near infrared light result in physiologic modulation are not fully understood. Heme moieties and copper within cells are red and near infrared light photoreceptors that induce the mitochondrial respiratory chain component cytochrome C oxidase, resulting in a cascade linked to cytoprotection and cellular metabolism. The copper centers in cytochrome C oxidase have a broad absorption range that peaks around 830 nm. Several in vitro and in vivo animal and human models exist that have demonstrated the benefits of red light and near infrared light for various conditions. Clinical applications for low level light therapy are varied. One study in particular demonstrated improved durable functional outcomes status post-stroke in patients treated with near infrared low level light therapy compared to sham treatment [1]. Despite previous data suggesting the beneficial effect in treating multiple conditions, including stroke, with low level light therapy, limited data exists that measures transmission in a human model. Study Design/Materials and Methods To investigate this idea, we measured the transmission of near infrared light energy, using red light for purposes of comparison, through intact cadaver soft tissue, skull bones, and brain using a commercially available LED device at 830 nm and 633 nm. Results Our results demonstrate that near infrared measurably penetrates soft tissue, bone and brain parenchyma in the formalin preserved cadaveric model, in comparison to negligible red light transmission in the same conditions. Conclusion These findings indicate that near infrared light can penetrate formalin fixed soft tissue, bone and brain and implicate that benefits observed in clinical studies are potentially related to direct action of near infrared light on neural tissue. PMID:23077622

Hα Emitting Galaxies at z ∼ 0.6 in the Deep And Wide Narrow-band Survey

NASA Astrophysics Data System (ADS)

Coughlin, Alicia; Rhoads, James E.; Malhotra, Sangeeta; Probst, Ronald; Swaters, Rob; Tilvi, Vithal S.; Zheng, Zhen-Ya; Finkelstein, Steven; Hibon, Pascale; Mobasher, Bahram; Jiang, Tianxing; Joshi, Bhavin; Pharo, John; Veilleux, Sylvain; Wang, Junxian; Yang, Huan; Zabl, Johannes

2018-05-01

We present new measurements of the Hα luminosity function (LF) and star formation rate (SFR) volume density for galaxies at z ∼ 0.62 in the COSMOS field. Our results are part of the Deep And Wide Narrow-band Survey (DAWN), a unique infrared imaging program with large areal coverage (∼1.1 deg2 over five fields) and sensitivity (9.9× {10}-18 {erg} {cm}}-2 {{{s}}}-1 at 5σ). The present sample, based on a single DAWN field, contains 116 Hα emission-line candidates at z ∼ 0.62, 25% of which have spectroscopic confirmations. These candidates have been selected through the comparison of narrow and broad-band images in the infrared and through matching with existing catalogs in the COSMOS field. The dust-corrected LF is well described by a Schechter function with {L}* ={10}42.64+/- 0.92 erg s‑1, {{{Φ }}}* ={10}-3.32+/- 0.93 Mpc‑3, {L}* {{{Φ }}}* ={10}39.40+/- 0.15 erg s‑1 Mpc‑3, and α = ‑1.75 ± 0.09. From this LF, we calculate a SFR density of ρ SFR = 10‑1.37 ± 0.08 M ⊙ yr‑1 Mpc‑3. We expect an additional cosmic variance uncertainty of ∼20%. Both the faint end slope and luminosity density that we derive are consistent with prior results at similar redshifts, with reduced uncertainties. We also present an analysis of these Hα emitters’ sizes, which shows a direct correlation between the galaxies’ sizes and their Hα emission.

A Cross-Sectional Survey of Near-Infrared Spectroscopy Use in Pediatric Cardiac ICUs in the United Kingdom, Ireland, Italy, and Germany.

PubMed

Hoskote, Aparna U; Tume, Lyvonne N; Trieschmann, Uwe; Menzel, Christoph; Cogo, Paola; Brown, Katherine L; Broadhead, Michael W

2016-01-01

Despite the increasing use of near-infrared spectroscopy across pediatric cardiac ICUs, there is significant variability and equipoise with no universally accepted management algorithms. We aimed to explore the use of near-infrared spectroscopy in pediatric cardiac ICUs in the United Kingdom, Ireland, Italy, and Germany. A cross-sectional multicenter, multinational electronic survey of one consultant in each pediatric cardiac ICU. Pediatric cardiac ICUs in the United Kingdom and Ireland (n = 13), Italy (n = 12), and Germany (n = 33). Questionnaire targeted to establish use, targets, protocols/thresholds for intervention, and perceived usefulness of near-infrared spectroscopy monitoring. Overall, 42 of 58 pediatric cardiac ICUs (72%) responded: United Kingdom and Ireland, 11 of 13 (84.6%); Italy, 12 of 12 (100%); and Germany, 19 of 33 (57%, included all major centers). Near-infrared spectroscopy usage varied with 35% (15/42) reporting that near-infrared spectroscopy was not used at all (7/42) or occasionally (8/42); near-infrared spectroscopy use was much less common in the United Kingdom (46%) when compared with 78% in Germany and all (100%) in Italy. Only four units had a near-infrared spectroscopy protocol, and 18 specifically used near-infrared spectroscopy in high-risk patients; 37 respondents believed that near-infrared spectroscopy added value to standard monitoring and 23 believed that it gave an earlier indication of deterioration, but only 19 would respond based on near-infrared spectroscopy data alone. Targets for absolute values and critical thresholds for intervention varied widely between units. The reasons cited for not or occasionally using near-infrared spectroscopy were expense (n = 6), limited evidence and uncertainty on how it guides management (n = 4), difficulty in interpretation, and unreliability of data (n = 3). Amongst the regular or occasional near-infrared spectroscopy users (n = 35), 28 (66%) agreed that a multicenter study is warranted

WFIRST: Astrometry with the Wide-Field Imager

NASA Astrophysics Data System (ADS)

Bellini, Andrea; WFIRST Astrometry Working Group

2018-01-01

The wide field of view and stable, sharp images delivered by WFIRST's Wide-Field Imager make it an excellent instrument for astrometry, one of five major discovery areas identified in the 2010 Decadal Survey. Compared to the Hubble Space Telescope, WFIRST's wider field of view with similar image quality will provide hundreds more astrometric targets per image as well as background galaxies and stars with precise positions in the Gaia catalog. In addition, WFIRST will operate in the infrared, a wavelength regime where the most precise astrometry has so far been achieved with adaptive optics images from large ground-based telescopes. WFIRST will provide at least a factor of three improvement in astrometry over the current state of the art in this wavelength range, while spanning a field of view thousands of times larger. WFIRST is thus poised to make major contributions to multiple science topics in which astrometry plays an important role, without major alterations to the planned mission or instrument. We summarize a few of the most compelling science cases where WFIRST astrometry could prove transformational.

TIRCAM2: The TIFR near infrared imaging camera

NASA Astrophysics Data System (ADS)

Naik, M. B.; Ojha, D. K.; Ghosh, S. K.; Poojary, S. S.; Jadhav, R. B.; Meshram, G. S.; Sandimani, P. R.; Bhagat, S. B.; D'Costa, S. L. A.; Gharat, S. M.; Bakalkar, C. B.; Ninan, J. P.; Joshi, J. S.

2012-12-01

TIRCAM2 (TIFR near infrared imaging camera - II) is a closed cycle cooled imager that has been developed by the Infrared Astronomy Group at the Tata Institute of Fundamental Research for observations in the near infrared band of 1 to 3.7 μm with existing Indian telescopes. In this paper, we describe some of the technical details of TIRCAM2 and report its observing capabilities, measured performance and limiting magnitudes with the 2-m IUCAA Girawali telescope and the 1.2-m PRL Gurushikhar telescope. The main highlight is the camera's capability of observing in the nbL (3.59 mum) band enabling our primary motivation of mapping of Polycyclic Aromatic Hydrocarbon (PAH) emission at 3.3 mum.

Analysis of Twenty-Two Performance Properties of Diesel, Gasoline, and Jet Fuels Using a Field-Portable Near-Infrared (NIR) Analyzer.

PubMed

Brouillette, Carl; Smith, Wayne; Shende, Chetan; Gladding, Zack; Farquharson, Stuart; Morris, Robert E; Cramer, Jeffrey A; Schmitigal, Joel

2016-05-01

The change in custody of fuel shipments at depots, pipelines, and ports could benefit from an analyzer that could rapidly verify that properties are within specifications. To meet this need, the design requirements for a fuel analyzer based on near-infrared (NIR) spectroscopy, such as spectral region and resolution, were examined. It was found that the 1000 to 1600 nm region, containing the second CH overtone and combination vibrational modes of hydrocarbons, provided the best near-infrared to fuel property correlations when path length was taken into account, whereas 4 cm(-1) resolution provided only a modest improvement compared to 16 cm(-1) resolution when four or more latent variables were used. Based on these results, a field-portable near-infrared fuel analyzer was built that employed an incandescent light source, sample compartment optics to hold 2 mL glass sample vials with ∼1 cm path length, a transmission grating, and a 256 channel InGaAs detector that measured the above stated wavelength range with 5-6 nm (∼32 cm(-1)) resolution. The analyzer produced high signal-to-noise ratio (SNR) spectra of samples in 5 s. Twenty-two property correlation models were developed for diesel, gasoline, and jet fuels with root mean squared error of correlation - cross-validated values that compared favorably to corresponding ASTM reproducibility values. The standard deviations of predicted properties for repeat measurements at 4, 24, and 38℃ were often better than ASTM documented repeatability values. The analyzer and diesel property models were tested by measuring seven diesel samples at a local ASTM certification laboratory. The standard deviations between the analyzer determined values and the ASTM measured values for these samples were generally better than the model root mean squared error of correlation-cross-validated values for each property. © The Author(s) 2016.

WISE Revises Numbers of Asteroids Near Earth

NASA Image and Video Library

2011-09-29

Data from NASA Wide-field Infrared Survey Explorer has led to revisions in the estimated population of near-Earth asteroids. The most accurate survey to date has allowed new estimates of the total numbers of objects in different size categories.

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

Remote sensing of the ocean contributions from ultraviolet to near-infrared using the shortwave infrared bands: simulations.

PubMed

Wang, Menghua

2007-03-20

In the remote sensing of the ocean near-surface properties, it is essential to derive accurate water-leaving radiance spectra through the process of the atmospheric correction. The atmospheric correction algorithm for Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer (MODIS) uses two near-infrared (NIR) bands at 765 and 865 nm (748 and 869 nm for MODIS) for retrieval of aerosol properties with assumption of the black ocean at the NIR wavelengths. Modifications are implemented to account for some of the NIR ocean contributions for the productive but not very turbid waters. For turbid waters in the coastal regions, however, the ocean could have significant contributions in the NIR, leading to significant errors in the satellite-derived ocean water-leaving radiances. For the shortwave infrared (SWIR) wavelengths (approximately > 1000 nm), water has significantly larger absorption than those for the NIR bands. Thus the black ocean assumption at the SWIR bands is generally valid for turbid waters. In addition, for future sensors, it is also useful to include the UV bands to better quantify the ocean organic and inorganic materials, as well as for help in atmospheric correction. Simulations are carried out to evaluate the performance of atmospheric correction for nonabsorbing and weakly absorbing aerosols using the NIR bands and various combinations of the SWIR bands for deriving the water-leaving radiances at the UV (340 nm) and visible wavelengths. Simulations show that atmospheric correction using the SWIR bands can generally produce results comparable to atmospheric correction using the NIR bands. In particular, the water-leaving radiance at the UV band (340 nm) can also be derived accurately. The results from a sensitivity study for the required sensor noise equivalent reflectance, (NE Delta rho), [or the signal-to-noise ratio (SNR)] for the NIR and SWIR bands are provided and discussed.

Plasmonic Resonance Enhanced Polarization-Sensitive Photodetection by Black Phosphorus in Near Infrared.

PubMed

Venuthurumilli, Prabhu K; Ye, Peide D; Xu, Xianfan

2018-05-22

Black phosphorus, a recently intensely investigated two-dimensional material, is promising for electronic and optoelectronic applications due to its higher mobility and thickness-dependent direct band gap. With its low direct band gap and anisotropic properties in nature, black phosphorus is also suitable for near-infrared polarization-sensitive photodetection. To enhance photoresponsivity of a black phosphorus based photodetector, we demonstrate two designs of plasmonic structures. In the first design, plasmonic bowtie antennas are used to increase the photocurrent, particularly in the armchair direction, where the optical absorption is higher than that in the zigzag direction. The simulated electric field distribution with bowtie structures shows enhanced optical absorption by localized surface plasmons. In the second design, bowtie apertures are used to enhance the inherent polarization selectivity of black phosphorus. A high photocurrent ratio (armchair to zigzag) of 8.7 is obtained. We choose a near-infrared wavelength of 1550 nm to demonstrate the photosensitivity enhancement and polarization selectivity, as it is useful for applications including telecommunication, remote sensing, biological imaging, and infrared polarimetry imaging.

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 (Φ Δ = 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.

OPTICAL IMAGES AND SOURCE CATALOG OF AKARI NORTH ECLIPTIC POLE WIDE SURVEY FIELD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeon, Yiseul; Im, Myungshin; Lee, Induk

2010-09-15

We present the source catalog and the properties of the B-, R-, and I-band images obtained to support the AKARI North Ecliptic Pole Wide (NEP-Wide) survey. The NEP-Wide is an AKARI infrared imaging survey of the north ecliptic pole covering a 5.8 deg{sup 2} area over 2.5-6 {mu}m wavelengths. The optical imaging data were obtained at the Maidanak Observatory in Uzbekistan using the Seoul National University 4k x 4k Camera on the 1.5 m telescope. These images cover 4.9 deg{sup 2} where no deep optical imaging data are available. Our B-, R-, and I-band data reach the depths of {approx}23.4,more » {approx}23.1, and {approx}22.3 mag (AB) at 5{sigma}, respectively. The source catalog contains 96,460 objects in the R band, and the astrometric accuracy is about 0.''15 at 1{sigma} in each R.A. and decl. direction. These photometric data will be useful for many studies including identification of optical counterparts of the infrared sources detected by AKARI, analysis of their spectral energy distributions from optical through infrared, and the selection of interesting objects to understand the obscured galaxy evolution.« less

Design of high-performance adaptive objective lens with large optical depth scanning range for ultrabroad near infrared microscopic imaging

PubMed Central

Lan, Gongpu; Mauger, Thomas F.; Li, Guoqiang

2015-01-01

We report on the theory and design of adaptive objective lens for ultra broadband near infrared light imaging with large dynamic optical depth scanning range by using an embedded tunable lens, which can find wide applications in deep tissue biomedical imaging systems, such as confocal microscope, optical coherence tomography (OCT), two-photon microscopy, etc., both in vivo and ex vivo. This design is based on, but not limited to, a home-made prototype of liquid-filled membrane lens with a clear aperture of 8mm and the thickness of 2.55mm ~3.18mm. It is beneficial to have an adaptive objective lens which allows an extended depth scanning range larger than the focal length zoom range, since this will keep the magnification of the whole system, numerical aperture (NA), field of view (FOV), and resolution more consistent. To achieve this goal, a systematic theory is presented, for the first time to our acknowledgment, by inserting the varifocal lens in between a front and a back solid lens group. The designed objective has a compact size (10mm-diameter and 15mm-length), ultrabroad working bandwidth (760nm - 920nm), a large depth scanning range (7.36mm in air) — 1.533 times of focal length zoom range (4.8mm in air), and a FOV around 1mm × 1mm. Diffraction-limited performance can be achieved within this ultrabroad bandwidth through all the scanning depth (the resolution is 2.22 μm - 2.81 μm, calculated at the wavelength of 800nm with the NA of 0.214 - 0.171). The chromatic focal shift value is within the depth of focus (field). The chromatic difference in distortion is nearly zero and the maximum distortion is less than 0.05%. PMID:26417508

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.

High resolution scanning of radial strips cut from increment cores by near infrared spectroscopy

Treesearch

P. David Jones; Laurence R. Schimleck; Chi-Leung So; Alexander III Clark; Richard F. Daniels

2007-01-01

Near infrared (NIR) spectroscopy provides a rapid method for the determination of wood properties of radial strips. The spatial resolution of the NIR measurements has generally been limited to sections 10 mm wide and as a consequence the estimation of wood properties of individual rings or within rings has not been possible. Many different NIR instruments can be used...

Near-Field Spectroscopy with Nanoparticles Deposited by AFM

NASA Technical Reports Server (NTRS)

Anderson, Mark S.

2008-01-01

An alternative approach to apertureless near-field optical spectroscopy involving an atomic-force microscope (AFM) entails less complexity of equipment than does a prior approach. The alternative approach has been demonstrated to be applicable to apertureless near-field optical spectroscopy of the type using an AFM and surface enhanced Raman scattering (SERS), and is expected to be equally applicable in cases in which infrared or fluorescence spectroscopy is used. Apertureless near-field optical spectroscopy is a means of performing spatially resolved analyses of chemical compositions of surface regions of nanostructured materials. In apertureless near-field spectroscopy, it is common practice to utilize nanostructured probe tips or nanoparticles (usually of gold) having shapes and dimensions chosen to exploit plasmon resonances so as to increase spectroscopic-signal strengths. To implement the particular prior approach to which the present approach is an alternative, it is necessary to integrate a Raman spectrometer with an AFM and to utilize a special SERS-active probe tip. The resulting instrumentation system is complex, and the tasks of designing and constructing the system and using the system to acquire spectro-chemical information from nanometer-scale regions on a surface are correspondingly demanding.

Near-Infrared Irradiation Increases Length of Axial Pattern Flap Survival in Rats.

PubMed

Yasunaga, Yoshichika; Matsuo, Kiyoshi; Tanaka, Yohei; Yuzuriha, Shunsuke

2017-01-01

Objective: We previously reported that near-infrared irradiation nonthermally induces long-lasting vasodilation of the subdermal plexus by causing apoptosis of vascular smooth muscle cells. To clarify the possible application of near-infrared irradiation to prevent skin flap necrosis, we evaluated the length of axial pattern flap survival in rats by near-infrared irradiation. Methods: A bilaterally symmetric island skin flap was elevated under the panniculus carnosus on the rat dorsum. Half of the flap was subjected to near-infrared irradiation just before flap elevation with a device that simulates solar radiation, which has a specialized contact cooling apparatus to avoid thermal effects. The length of flap survival of the near-infrared irradiated side was measured 7 days after flap elevation and compared with the nonirradiated side. Results: The irradiated side showed elongation of flap survival compared with the nonirradiated side (73.3 ± 11.7 mm vs 67.3 ± 14.9 mm, respectively, P = .03). Conclusions: Near-infrared irradiation increases the survival length of axial pattern flaps in rats.

Wide-field Astronomy Projects at the UKATC

NASA Astrophysics Data System (ADS)

Hawarden, T. G.; Casali, M. M.; Holland, W. S.; Ivison, R. J.; Wright, G. S.

2001-12-01

The UK Astronomy Technology Centre is engaged on a number of projects which are defining the stare of the art in several areas of wide-field astronomy. The most advanced of these will equip the UK Infrared Telescope (UKIRT) with a wide-field NIR (1 - 2.5 um) imager, WFCAM, in 2003. WFCAM will use 4 2k-square HgCdTe arrays to cover 0.19 square degrees in a single exposure. It will have 0."4 pixels and will employ multiple exposures (16 in the basic case) and microstepping to obtain full sampling of the PSF. WFCAM will reach K=19.4 at 5 sigma over 1 sq. deg. in 1 hour. Several deep surveys are planned; details are at http://www.roe.ac.uk/atc/projects/wfcam/science/. The project is in collaboration with the SUBARU telescope of the National Astronomy Observatory of Japan. Major data centres and archives will be established within the UK widefield astronomy groups and at SUBARU. SCUBA, on the JCMT, is currently the most-cited facility in Astronomy after the HST. Plans and technology development are well advanced for its replacement, SCUBA-2. This ambitious instrument is also an imager working at 450 and 850 um, but with greatly enlarged FOV and improved sensitivity. Technical developments at the NIST, Boulder, Co. are aimed at producing 2 6400-pixel arrays of Transition Edge Sensors, covering 8' x 8', with a system NEFD of 30mJy at 850 and 100 mJy at 450um. The 850 um FOV will be fully sampled; the 450 um FOV will be 2X undersampled. SCUBA-2 will be able to make a confusion-limited survey of 1 ° 2 of sky in just 24 hours of observing; indeed it will map large areas of sky up to an order of magnitude faster than ALMA in compact mode; it will make major new contributions to all areas of astronomy, from the solar system to Z=10 galaxies. Lastly, designs are well advanced for a powerful multiple cryogenic Integral Field spectroscopic facility. The design is well suited to VLTs or ELTs and will employ up to 8 unit spectrometers, each with a 2k2 array fed by four cryogenic

Thermal Infrared and Visible to Near-Infrared Spectral Analysis of Chert and Amorphous Silica

NASA Astrophysics Data System (ADS)

McDowell, M. L.; Hamilton, V. E.; Cady, S. L.; Knauth, P.

2009-03-01

We look in detail at the thermal infrared and visible to near-infrared spectra of various forms of chert and amorphous silica and compare the spectral variations between samples with variations in physical and chemical characteristics.

White organic light-emitting diodes utilized by near UV-deep blue emitter and exciplex emission.

PubMed

Park, Young Wook; Kim, Young Min; Choi, Jin Hwan; Park, Tae Hyun; Choi, Hyun Ju; Yu, Hong Jung; Cho, Min Ju; Choi, Dong Hoon; Kim, Sung Hyun; Ju, Byeong Kwon

2011-02-01

Numerous investigations have been made into the development of wide color gamut displays for deep-blue OLEDs, including the RGB sub pixels, and white OLEDs (WOLEDs). One of the well known deep-blue emissive dopants, tris(phenyl-methyl-benzimidazolyl)iridium(III) [Ir(pmb)3], successfully introduced its fascinating color coordinate of Commission Internationale de l'Eclairage (CIE) 1931 (0.17, 0.06), however there have been no reports utilizing its accomplishments as WOLEDs. In this report, using only one phosphorescent dopant, the near UV-deep blue emissive Ir(pmb)3, the WOLEDs having the CIE 1931 coordinate of (0.33, 0.38) at 100 cd/m2 with a color rendering index of 85 are demonstrated. The white emission of the fabricated OLEDs are oriented from the near UV-deep blue emission of Ir(pmb)3 and the successfully controlled exciplex emission, between the Ir(pmb)3-host, and the Ir(pmb)3-interfaced material.

Effect of near-infrared rays on female menstrual pain in Korea.

PubMed

Lee, Jin-Min; Kim, Kye-Ha

2017-09-01

Most Korean women who experience menstrual pain have reported taking pain medicine and making use of complementary alternative therapies. However, because some interventions may cause side effects, more effective pain-relieving measures need to be identified. This study using a non-equivalent group design, evaluated the effects of near-infrared rays on dysmenorrhea among Korean women. The experimental group wore a near-infrared ray abdominal belt for the duration of one menstrual cycle until the end of the menstrual period, while the control group used hot packs. The level of menstrual pain, menstrual pain duration, and pain medicine use were measured. The menstrual pain, average menstrual pain duration, and use of analgesics were reduced in the near-infrared rays group. The results of this study indicate that the near-infrared ray LED belt was effective in reducing menstrual pain, menstrual pain duration compared to the use of analgesics in Korean women with dysmenorrhea. Therefore, near-infrared rays may be used to relieve menstrual pain and improve the quality of life of women with dysmenorrhea in Korea. © 2017 John Wiley & Sons Australia, Ltd.

Detector Control and Data Acquisition for the Wide-Field Infrared Survey Telescope (WFIRST) with a Custom ASIC

NASA Technical Reports Server (NTRS)

Smith, Brian S.; Loose, Markus; Alkire, Greg; Joshi, Atul; Kelly, Daniel; Siskind, Eric; Rossetti, Dino; Mah, Jonathan; Cheng, Edward; Miko, Laddawan;

The SCUBA-2 Cosmology Legacy Survey: the EGS deep field - I. Deep number counts and the redshift distribution of the recovered cosmic infrared background at 450 and 850 μ m

NASA Astrophysics Data System (ADS)

Zavala, J. A.; Aretxaga, I.; Geach, J. E.; Hughes, D. H.; Birkinshaw, M.; Chapin, E.; Chapman, S.; Chen, Chian-Chou; Clements, D. L.; Dunlop, J. S.; Farrah, D.; Ivison, R. J.; Jenness, T.; Michałowski, M. J.; Robson, E. I.; Scott, Douglas; Simpson, J.; Spaans, M.; van der Werf, P.

2017-01-01

We present deep observations at 450 and 850 μm in the Extended Groth Strip field taken with the SCUBA-2 camera mounted on the James Clerk Maxwell Telescope as part of the deep SCUBA-2 Cosmology Legacy Survey (S2CLS), achieving a central instrumental depth of σ450 = 1.2 mJy beam-1 and σ850 = 0.2 mJy beam-1. We detect 57 sources at 450 μm and 90 at 850 μm with signal-to-noise ratio >3.5 over ˜70 arcmin2. From these detections, we derive the number counts at flux densities S450 > 4.0 mJy and S850 > 0.9 mJy, which represent the deepest number counts at these wavelengths derived using directly extracted sources from only blank-field observations with a single-dish telescope. Our measurements smoothly connect the gap between previous shallower blank-field single-dish observations and deep interferometric ALMA results. We estimate the contribution of our SCUBA-2 detected galaxies to the cosmic infrared background (CIB), as well as the contribution of 24 μm-selected galaxies through a stacking technique, which add a total of 0.26 ± 0.03 and 0.07 ± 0.01 MJy sr-1, at 450 and 850 μm, respectively. These surface brightnesses correspond to 60 ± 20 and 50 ± 20 per cent of the total CIB measurements, where the errors are dominated by those of the total CIB. Using the photometric redshifts of the 24 μm-selected sample and the redshift distributions of the submillimetre galaxies, we find that the redshift distribution of the recovered CIB is different at each wavelength, with a peak at z ˜ 1 for 450 μm and at z ˜ 2 for 850 μm, consistent with previous observations and theoretical models.

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.

First Near-infrared Imaging Polarimetry of Young Stellar Objects in the Circinus Molecular Cloud

NASA Astrophysics Data System (ADS)

Kwon, Jungmi; Nakagawa, Takao; Tamura, Motohide; Hough, James H.; Choi, Minho; Kandori, Ryo; Nagata, Tetsuya; Kang, Miju

2018-02-01

We present the results of near-infrared (NIR) linear imaging polarimetry in the J, H, and K s bands of the low-mass star cluster-forming region in the Circinus Molecular Cloud Complex. Using aperture polarimetry of point-like sources, positive detection of 314, 421, and 164 sources in the J, H, and K s bands, respectively, was determined from among 749 sources whose photometric magnitudes were measured. For the source classification of the 133 point-like sources whose polarization could be measured in all 3 bands, a color–color diagram was used. While most of the NIR polarizations of point-like sources are well-aligned and can be explained by dichroic polarization produced by aligned interstellar dust grains in the cloud, 123 highly polarized sources have also been identified with some criteria. The projected direction on the sky of the magnetic field in the Cir-MMS region is indicated by the mean polarization position angles (70°) of the point-like sources in the observed region, corresponding to approximately 1.6× 1.6 pc2. In addition, the magnetic field direction is compared with the outflow orientations associated with Infrared Astronomy Satellite sources, in which two sources were found to be aligned with each other and one source was not. We also show prominent polarization nebulosities over the Cir-MMS region for the first time. Our polarization data have revealed one clear infrared reflection nebula (IRN) and several candidate IRNe in the Cir-MMS field. In addition, the illuminating sources of the IRNe are identified with near- and mid-infrared sources.

Design and Fabrication of nanowire-grid polarizer in near-infrared broadband

NASA Astrophysics Data System (ADS)

Jin, Qiufeng; Liu, Quan; Wu, Jianhong; Cheng, Yu

2012-11-01

The infrared polarizers are widely used in the infrared imaging systems as the core components, such as infrared stealth, target acquisition and mine detection, automobile night-vision instrument and other systems. For the requirements of near-infrared imaging systems, a nanowire-grid is designed by Finite Difference Time Domain (FDTD) method. Herein, considering the high reflection of metal aluminum in the manufacturing process, we propose a structure with aluminum-copper nanowire-grid. FDTD method is adapted to analyze the effects of the thickness of aluminumcopper in different combinations on the TM and TE polarization transmission efficiency as well as the extinction ratio when the grating's period is 300nm. Numerical results and theoretical analysis show that: the reflection on the substrate is suppressed with the optimal thickness of the Cu layer. Considering the resist-substrate reflectivity and the final performance of the polarizer, the structure with an 120nm Al layer, and a 50nm anti-reflection Cu layer is chosen; and the TM transmission efficiency is more than 71%, and the extinction ratio is more than 25dB. At last we used Holographic lithography and IBE to fabricate a prototype of the nanowire-grid.

Citrus species and hybrids depicted by near- and mid-infrared spectroscopy.

PubMed

Páscoa, Ricardo Nmj; Moreira, Silvana; Lopes, João A; Sousa, Clara

2018-01-31

Citrus trees are among the most cultivated plants in the world, with a high economic impact. The wide sexual compatibility among relatives gave rise to a large number of hybrids that are difficult to discriminate. This work sought to explore the ability of infrared spectroscopy to discriminate among Citrus species and/or hybrids and to contribute to the elucidation of its relatedness. Adult leaves of 18 distinct Citrus plants were included in this work. Near- and mid-infrared (NIR and FTIR) spectra were acquired from leaves after harvesting and a drying period of 1 month. Spectra were modelled by principal component analysis and partial least squares discriminant analysis. Both techniques revealed a high discrimination potential (78.5-95.9%), being the best results achieved with NIR spectroscopy and air-dried leaves (95.9%). Infrared spectroscopy was able to successfully discriminate several Citrus species and/or hybrids. Our results contributed also to enhance insights regarding the studied Citrus species and/or hybrids. Despite the benefit of including additional samples, the results herein obtained clearly pointed infrared spectroscopy as a reliable technique for Citrus species and/or hybrid discrimination. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Measuring Snow Grain Size with the Near-Infrared Emitting Reflectance Dome (NERD)

NASA Astrophysics Data System (ADS)

Schneider, A. M.; Flanner, M.

2014-12-01

Because of its high visible albedo, snow plays a large role in Earth's surface energy balance. This role is a subject of intense study, but due to the wide range of snow albedo, variations in the characteristics of snow grains can introduce radiative feedbacks in a snow pack. Snow grain size, for example, is one property which directly affects a snow pack's absorption spectrum. Previous studies model and observe this spectrum, but potential feedbacks induced by these variations are largely unknown. Here, we implement a simple and inexpensive technique to measure snow grain size in an instrument we call the Near-infrared Emitting Reflectance Dome (NERD). A small black styrene dome (~17cm diameter), fitted with two narrowband light-emitting diodes (LEDs) centered around 1300nm and 1550nm and three near-infrared reverse-biased photodiodes, is placed over the snow surface enabling a multi-spectral measurement of the hemispheric directional reflectance factor (HDRF). We illuminate the snow at each wavelength, measure directional reflectance, and infer grain size from the difference in HDRFs measured on the same snow crystals at fixed viewing angles. We validate measurements from the NERD using two different reflectance standards, materials designed to be near perfect Lambertian reflectors, having known, constant reflectances (~99% and ~55%) across a wide range of wavelengths. Using a 3D Monte Carlo model simulating photon pathways through a pack of spherical snow grains, we calculate the difference in HDRFs at 1300nm and 1550nm to predict the calibration curve for a wide range of grain sizes. This theoretically derived curve gives a relationship between effective radius and the difference in HDRFs and allows us to approximate grain sizes using the NERD in just a few seconds. Further calibration requires knowledge of truth values attainable using a previously validated instrument or measurements from an inter-comparison workshop.

Cosmic Accretion and Galaxy Co-Evolution: Lessons from the Extended Chandra Deep Field South

NASA Astrophysics Data System (ADS)

Urry, C. Megan

2011-05-01

The Chandra deep fields reveal that most cosmic accretion onto supermassive black holes is obscured by gas and dust. The GOODS and MUSYC multiwavelength data show that many X-ray-detected AGN are faint and red (or even undetectable) in the optical but bright in the infrared, as is characteristic of obscured sources. (N.B. The ECDFS is most sensitive to the AGN that constitute the X-ray background, namely, moderate luminosity AGN, with log Lx=43-44, at moderate redshifts, 0.5field, using deep medium-band optical imaging in 18 filters with Subaru's Suprime-Cam, we can derive the color-mass distributions out to z<1.2. (With deep near-IR HST imaging and spectroscopy we can extend this to z 2.5.) After correcting for dust reddening, we find that AGN host galaxies at z 1 are either newly arrived on the red sequence or still forming stars in the blue cloud, while at z 0 most AGN hosts are in the green valley, avoiding the blue cloud. These results suggest two modes of black hole growth: a vigorous initial phase that may be strong enough to turn off star formation, and a later moderate phase, on the red sequence, sufficient to keep gas too hot for star formation. At lower redshifts, this activity has mostly died down, presumably because there is less gas available for star formation or accretion.

Using lead chalcogenide nanocrystals as spin mixers: a perspective on near-infrared-to-visible upconversion.

PubMed

Nienhaus, Lea; Wu, Mengfei; Bulović, Vladimir; Baldo, Marc A; Bawendi, Moungi G

2018-03-01

The process of upconversion leads to emission of photons higher in energy than the incident photons. Near-infrared-to-visible upconversion, in particular, shows promise in sub-bandgap sensitization of silicon and other optoelectronic materials, resulting in potential applications ranging from photovoltaics that exceed the Shockley-Queisser limit to infrared imaging. A feasible mechanism for near-infrared-to-visible upconversion is triplet-triplet annihilation (TTA) sensitized by colloidal nanocrystals (NCs). Here, the long lifetime of spin-triplet excitons in the organic materials that undergo TTA makes upconversion possible under incoherent excitation at relatively low photon fluxes. Since this process relies on optically inactive triplet states, semiconductor NCs are utilized as efficient spin mixers, absorbing the incident light and sensitizing the triplet states of the TTA material. The state-of-the-art system uses rubrene with a triplet energy of 1.14 eV as the TTA medium, and thus allows upconversion of light with photon energies above ∼1.1 eV. In this perspective, we review the field of lead sulfide (PbS) NC-sensitized near-infrared-to-visible upconversion, discuss solution-based upconversion, and highlight progress made on solid-state upconversion devices.

Authenticity assessment of banknotes using portable near infrared spectrometer and chemometrics.

PubMed

da Silva Oliveira, Vanessa; Honorato, Ricardo Saldanha; Honorato, Fernanda Araújo; Pereira, Claudete Fernandes

2018-05-01

Spectra recorded using a portable near infrared (NIR) spectrometer, Soft Independent Modeling of Class Analogy (SIMCA) and Linear Discriminant Analysis (LDA) associated to Successive Projections Algorithm (SPA) models were applied to identify counterfeit and authentic Brazilian Real (R$20, R$50 and R$100) banknotes, enabling a simple field analysis. NIR spectra (950-1650nm) were recorded from seven different areas of the banknotes (two with fluorescent ink, one over watermark, three with intaglio printing process and one over the serial numbers with typography printing). SIMCA and SPA-LDA models were built using 1st derivative preprocessed spectral data from one of the intaglio areas. For the SIMCA models, all authentic (300) banknotes were correctly classified and the counterfeits (227) were not classified. For the two classes SPA-LDA models (authentic and counterfeit currencies), all the test samples were correctly classified into their respective class. The number of selected variables by SPA varied from two to nineteen for R$20, R$50 and R$100 currencies. These results show that the use of the portable near-infrared with SIMCA or SPA-LDA models can be a completely effective, fast, and non-destructive way to identify authenticity of banknotes as well as permitting field analysis. Copyright © 2018 Elsevier B.V. All rights reserved.

Near infrared absorbing near infrared emitting highly-sensitive luminescent nanothermometer based on Nd(3+) to Yb(3+) energy transfer.

PubMed

Marciniak, Ł; Bednarkiewicz, A; Stefanski, M; Tomala, R; Hreniak, D; Strek, W

2015-10-07

A new type of near infrared absorbing near infrared emitting (NANE) luminescent nanothermometer is presented, with a physical background that relies on efficient Nd(3+) to Yb(3+) energy transfer under 808 nm photo-excitation. The emission spectra of LiLa0.9-xNd0.1YbxP4O12 (x = 0.05, 0.1, 0.2, 0.3, 0.5) nanocrystals were measured in a wide 100-700 °C temperature range. The ratio between the Nd(3+) ((4)F3/2→(4)I9/2) and Yb(3+) ((2)F5/2→(2)F7/2) luminescence bands, and the thermometer sensitivity were found to be strongly dependent on the Yb(3+) concentration. These phenomenological relations were discussed in terms of the competition between three phenomena, namely (a) Nd(3+)→ Yb(3+) phonon assisted energy transfer, (b) Yb(3+)→ Nd(3+) back energy transfer and (c) energy diffusion between Yb(3+) ions. The highest sensitivity of the temperature measurement was found for x = 0.5 (LiLa0.4Nd0.1Yb0.5P4O12), which was equal to 4 × 10(-3) K(-1) at 330 K. In stark contrast to conventional approaches, the proposed phosphate host matrix allows for a high level of doping, and thus, owing to the negligible concentration quenching, the presented luminophores exhibit a high absorption cross section and bright emission. Moreover, such optical remote thermometers, whose excitation and emission wavelengths are weakly scattered or absorbed and fall into the optical transmission window of the skin, may therefore become a practical solution for biomedical applications, such as remote control of thermotherapy.

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.

Numerical investigation of narrowband infrared absorber and sensor based on dielectric-metal metasurface.

PubMed

Lu, Xiaoyuan; Zhang, Tongyi; Wan, Rengang; Xu, Yongtao; Zhao, Changhong; Guo, Sheng

2018-04-16

Metasurfaces are investigated intensively for biophotonics applications due to their resonant wavelength flexibly tuned in the near infrared region specially matching biological tissues. Here, we present numerically a metasurface structure combining dielectric resonance with surface plasmon mode of a metal plane, which is a perfect absorber with a narrow linewidth 10 nm wide and quality factor 120 in the near infrared regime. As a sensor, its bulk sensitivity and bulk figure of merit reach respectively 840 nm/RIU and 84/RIU, while its surface sensitivity and surface figure of merit are respectively 1 and 0.1/nm. For different types of adsorbate layers with the same thickness of 8 nm, its surface sensitivity and figure of merit are respectively 32.3 and 3.2/RIU. The enhanced electric field is concentrated on top of dielectric patch ends and in the patch ends simultaneously. Results show that the presented structure has high surface (and bulk) sensing capability in sensing applications due to its narrow linewidth and deep modulation depth. This could pave a new route toward dielectric-metal metasurface in biosensing applications, such as early disease detections and designs of neural stem cell sensing platforms.

[Evaluation of Sugar Content of Huanghua Pear on Trees by Visible/Near Infrared Spectroscopy].

PubMed

Liu, Hui-jun; Ying, Yi-bin

2015-11-01

A method of ambient light correction was proposed to evaluate the sugar content of Huanghua pears on tree by visible/near infrared diffuse reflectance spectroscopy (Vis/NIRS). Due to strong interference of ambient light, it was difficult to collect the efficient spectral of pears on tree. In the field, covering the fruits with a bag blocking ambient light can get better results, but the efficiency is fairly low, the instrument corrections of dark and reference spectra may help to reduce the error of the model, however, the interference of the ambient light cannot be eliminated effectively. In order to reduce the effect of ambient light, a shutter was attached to the front of probe. When opening shutter, the spot spectrum were obtained, on which instrument light and ambient light acted at the same time. While closing shutter, background spectra were obtained, on which only ambient light acted, then the ambient light spectra was subtracted from spot spectra. Prediction models were built using data on tree (before and after ambient light correction) and after harvesting by partial least square (PLS). The results of the correlation coefficient (R) are 0.1, 0.69, 0.924; the root mean square error of prediction (SEP) are 0. 89°Brix, 0.42°Brix, 0.27°Brix; ratio of standard deviation (SD) to SEP (RPD) are 0.79, 1.69, 2.58, respectively. The results indicate that, method of background correction used in the experiment can reduce the effect of ambient lighting on spectral acquisition of Huanghua pears in field, efficiently. This method can be used to collect the visible/near infrared spectrum of fruits in field, and may give full play to visible/near-infrared spectroscopy in preharvest management and maturity testing of fruits in the field.

Near-field observation platform

NASA Astrophysics Data System (ADS)

Schlemmer, Harry; Baeurle, Constantin; Vogel, Holger

2008-04-01

A miniaturized near-field observation platform is presented comprising a sensitive daylight camera and an uncooled micro-bolometer thermal imager each equipped with a wide angle lens. Both cameras are optimised for a range between a few meters and 200 m. The platform features a stabilised line of sight and can therefore be used also on a vehicle when it is in motion. The line of sight either can be directed manually or the platform can be used in a panoramic mode. The video output is connected to a control panel where algorithms for moving target indication or tracking can be applied in order to support the observer. The near-field platform also can be netted with the vehicle system and the signals can be utilised, e.g. to designate a new target to the main periscope or the weapon sight.

A near-infrared SETI experiment: A multi-time resolution data analysis

NASA Astrophysics Data System (ADS)

Tallis, Melisa; Maire, Jerome; Wright, Shelley; Drake, Frank D.; Duenas, Andres; Marcy, Geoffrey W.; Stone, Remington P. S.; Treffers, Richard R.; Werthimer, Dan; NIROSETI

2016-06-01

We present new post-processing routines which are used to detect very fast optical and near-infrared pulsed signals using the latest NIROSETI (Near-Infrared Optical Search for Extraterrestrial Intelligence) instrument. NIROSETI was commissioned in 2015 at Lick Observatory and searches for near-infrared (0.95 to 1.65μ) nanosecond pulsed laser signals transmitted by distant civilizations. Traditional optical SETI searches rely on analysis of coincidences that occur between multiple detectors at a fixed time resolution. We present a multi-time resolution data analysis that extends our search from the 1ns to 1ms range. This new feature greatly improves the versatility of the instrument and its search parameters for near-infrared SETI. We aim to use these algorithms to assist us in our search for signals that have varying duty cycles and pulse widths. We tested the fidelity and robustness of our algorithms using both synthetic embedded pulsed signals, as well as data from a near-infrared pulsed laser installed on the instrument. Applications of NIROSETI are widespread in time domain astrophysics, especially for high time resolution transients, and astronomical objects that emit short-duration high-energy pulses such as pulsars.

Magnetic fields in the Perseus Spiral Arm and in Infrared Dark Clouds

NASA Astrophysics Data System (ADS)

Hoq, Sadia

2017-04-01

The magnetic (B) field is ubiquitous throughout the Milky Way. Several fundamental questions about the B-field in the cool, star-forming interstellar medium (ISM) remain unanswered. In this dissertation, near-infrared (NIR) polarimetric observations are used to study the large-scale Galactic B-field in the cool ISM in a spiral arm and to determine the role of B-fields in the formation of Infrared Dark Clouds (IRDCs). NIR polarimetry of 31 star clusters, located in and around the Perseus spiral arm, were obtained to determine the orientation of the plane-of-sky B-field in the outer Galaxy, and whether the presence of a spiral arm influenced B-field properties. Cluster distances, which provide upper limits to the B-field probed by observations, were estimated by developing a maximum likelihood method to fit theoretical stellar isochrones to stars in cluster color-magnitude diagrams (CMDs). Using the distance estimates, the cluster locations relative to the Perseus arm were found. The cluster polarization percentages and orientations were compared between clusters foreground to the arm and clusters inside or behind the arm. The cluster polarization orientations are predominantly parallel to the Galactic plane. Clusters inside and behind the arm have larger polarization percentages, likely a result of more polarizing material along the line of sight. The cluster polarization data were also compared to optical, inner Galaxy NIR, and Planck submm polarimetry data, and showed agreement with all three data sets. The polarimetric properties of one IRDC, G28.23, were determined using deep NIR observations. The polarization orientations relative to the cloud major axis were found to change directions with distance from the cloud axis. The B-field strength was estimated to be 10 to 100microG. Despite these large inferred B-field strengths, the B-field was found not to be the dominant force in the formation of the IRDC, though the B-field morphology was influenced by the cloud

[Rapid discriminating hogwash oil and edible vegetable oil using near infrared optical fiber spectrometer technique].

PubMed

Zhang, Bing-Fang; Yuan, Li-Bo; Kong, Qing-Ming; Shen, Wei-Zheng; Zhang, Bing-Xiu; Liu, Cheng-Hai

2014-10-01

In the present study, a new method using near infrared spectroscopy combined with optical fiber sensing technology was applied to the analysis of hogwash oil in blended oil. The 50 samples were a blend of frying oil and "nine three" soybean oil according to a certain volume ratio. The near infrared transmission spectroscopies were collected and the quantitative analysis model of frying oil was established by partial least squares (PLS) and BP artificial neural network The coefficients of determina- tion of calibration sets were 0.908 and 0.934 respectively. The coefficients of determination of validation sets were 0.961 and 0.952, the root mean square error of calibrations (RMSEC) was 0.184 and 0.136, and the root mean square error of predictions (RMSEP) was all 0.111 6. They conform to the model application requirement. At the same time, frying oil and qualified edible oil were identified with the principal component analysis (PCA), and the accurate rate was 100%. The experiment proved that near infrared spectral technology not only can quickly and accurately identify hogwash oil, but also can quantitatively detect hog- wash oil. This method has a wide application prospect in the detection of oil.

Kilonova from post-merger ejecta as an optical and near-Infrared counterpart of GW170817

NASA Astrophysics Data System (ADS)

Tanaka, Masaomi; Utsumi, Yousuke; Mazzali, Paolo A.; Tominaga, Nozomu; Yoshida, Michitoshi; Sekiguchi, Yuichiro; Morokuma, Tomoki; Motohara, Kentaro; Ohta, Kouji; Kawabata, Koji S.; Abe, Fumio; Aoki, Kentaro; Asakura, Yuichiro; Baar, Stefan; Barway, Sudhanshu; Bond, Ian A.; Doi, Mamoru; Fujiyoshi, Takuya; Furusawa, Hisanori; Honda, Satoshi; Itoh, Yoichi; Kawabata, Miho; Kawai, Nobuyuki; Kim, Ji Hoon; Lee, Chien-Hsiu; Miyazaki, Shota; Morihana, Kumiko; Nagashima, Hiroki; Nagayama, Takahiro; Nakaoka, Tatsuya; Nakata, Fumiaki; Ohsawa, Ryou; Ohshima, Tomohito; Okita, Hirofumi; Saito, Tomoki; Sumi, Takahiro; Tajitsu, Akito; Takahashi, Jun; Takayama, Masaki; Tamura, Yoichi; Tanaka, Ichi; Terai, Tsuyoshi; Tristram, Paul J.; Yasuda, Naoki; Zenko, Tetsuya

2017-12-01

Recent detection of gravitational waves from a neutron star (NS) merger event GW170817 and identification of an electromagnetic counterpart provide a unique opportunity to study the physical processes in NS mergers. To derive properties of ejected material from the NS merger, we perform radiative transfer simulations of kilonova, optical and near-infrared emissions powered by radioactive decays of r-process nuclei synthesized in the merger. We find that the observed near-infrared emission lasting for >10 d is explained by 0.03 M⊙ of ejecta containing lanthanide elements. However, the blue optical component observed at the initial phases requires an ejecta component with a relatively high electron fraction (Ye). We show that both optical and near-infrared emissions are simultaneously reproduced by the ejecta with a medium Ye of ˜0.25. We suggest that a dominant component powering the emission is post-merger ejecta, which exhibits that the mass ejection after the first dynamical ejection is quite efficient. Our results indicate that NS mergers synthesize a wide range of r-process elements and strengthen the hypothesis that NS mergers are the origin of r-process elements in the Universe.

Leaf Chlorophyll Content Estimation of Winter Wheat Based on Visible and Near-Infrared Sensors.

PubMed

Zhang, Jianfeng; Han, Wenting; Huang, Lvwen; Zhang, Zhiyong; Ma, Yimian; Hu, Yamin

2016-03-25

The leaf chlorophyll content is one of the most important factors for the growth of winter wheat. Visual and near-infrared sensors are a quick and non-destructive testing technology for the estimation of crop leaf chlorophyll content. In this paper, a new approach is developed for leaf chlorophyll content estimation of winter wheat based on visible and near-infrared sensors. First, the sliding window smoothing (SWS) was integrated with the multiplicative scatter correction (MSC) or the standard normal variable transformation (SNV) to preprocess the reflectance spectra images of wheat leaves. Then, a model for the relationship between the leaf relative chlorophyll content and the reflectance spectra was developed using the partial least squares (PLS) and the back propagation neural network. A total of 300 samples from areas surrounding Yangling, China, were used for the experimental studies. The samples of visible and near-infrared spectroscopy at the wavelength of 450,900 nm were preprocessed using SWS, MSC and SNV. The experimental results indicate that the preprocessing using SWS and SNV and then modeling using PLS can achieve the most accurate estimation, with the correlation coefficient at 0.8492 and the root mean square error at 1.7216. Thus, the proposed approach can be widely used for winter wheat chlorophyll content analysis.

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.

Variability Survey of ω Centauri in the Near-IR: Period-Luminosity Relations

NASA Astrophysics Data System (ADS)

Navarrete, Camila; Catelan, Márcio; Contreras Ramos, Rodrigo; Gran, Felipe; Alonso-García, Javier; Dékány, István

2015-08-01

ω Centauri (NGC 5139) is by far the most massive globular star cluster in the Milky Way, and has even been suggested to be the remnant of a dwarf galaxy. As such, it contains a large number of variable stars of different classes. Here we report on a deep, wide-field, near-infrared variability survey of omega Cen, carried out by our team using ESO's 4.1m VISTA telescope. Our time-series data comprise 42 and 100 epochs in J and Ks, respectively. This unique dataset has allowed us to derive complete light curves for hundreds of variable stars in the cluster, and thereby perform a detailed analysis of the near-infrared period-luminosity (PL) relations for different variability classes, including type II Cepheids, SX Phoenicis, and RR Lyrae stars. In this contribution, in addition to describing our survey and presenting the derived light curves, we present the resulting PL relations for each of these variability classes, including the first calibration of this sort for the SX Phoenicis stars. Based on these relations, we also provide an updated (pulsational) distance modulus for omega Cen, compare with results based on independent techniques, and discuss possible sources of systematic errors.

AKARI/IRC NEAR-INFRARED SPECTRAL ATLAS OF GALACTIC PLANETARY NEBULAE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohsawa, Ryou; Onaka, Takashi; Sakon, Itsuki

2016-04-15

Near-infrared (2.5–5.0 μm) low-resolution (λ/Δλ ∼ 100) spectra of 72 Galactic planetary nebulae (PNe) were obtained with the Infrared Camera (IRC) in the post-helium phase. The IRC, equipped with a 1′ × 1′ window for spectroscopy of a point source, was capable of obtaining near-infrared spectra in a slit-less mode without any flux loss due to a slit. The spectra show emission features including hydrogen recombination lines and the 3.3–3.5 μm hydrocarbon features. The intensity and equivalent width of the emission features were measured by spectral fitting. We made a catalog providing unique information on the investigation of the near-infrared emission ofmore » PNe. In this paper, details of the observations and characteristics of the catalog are described.« less

Inverse opal photonic crystals with photonic band gaps in the visible and near-infrared

NASA Astrophysics Data System (ADS)

Jarvis, Brandon C.; Gilleland, Cody L.; Renfro, Tim; Gutierrez, Jose; Parikh, Kunjal; Glosser, R.; Landon, Preston B.

2005-08-01

Colloidal silica spheres with 200nm, 250nm, and 290nm diameters were self-assembled with single crystal crystallites 4-5mm wide and 10-15mm long. Larger spheres with diameters between 1000-2300nm were self-assembled with single crystal crystallites up to 1.5mm wide and 2mm long. The silica opals self-assembled vertically along the [100] direction of the face centered cubic lattice resulting in self-templated opals. Inverse opal photonic crystals with a partial band gap possessing a maximum in the near infrared at 3.8μm were constructed from opal templates composed of 2300nm diameter spheres with chalcogenide Ge33As12Se55 (AMTIR-1), a transparent glass in the near infrared with high refractive index. Inverse gold and gold/ polypropylene composite photonic crystals were fabricated from synthetic opal templates composed of 200-290nm silica spheres. The reflectance spectra and electrical conductance of the resulting structures is presented. Gold was infiltrated into opal templates as gold chloride and heat converted to metallic gold. Opals partially infiltrated with gold were co-infiltrated with polypropylene plastic for mechanical support prior to removal of the silica template with hydrofluoric acid.

Near-Infrared Fluorescent Nanoprobes for Revealing the Role of Dopamine in Drug Addiction.

PubMed

Feng, Peijian; Chen, Yulei; Zhang, Lei; Qian, Cheng-Gen; Xiao, Xuanzhong; Han, Xu; Shen, Qun-Dong

2018-02-07

Brain imaging techniques enable visualizing the activity of central nervous system without invasive neurosurgery. Dopamine is an important neurotransmitter. Its fluctuation in brain leads to a wide range of diseases and disorders, like drug addiction, depression, and Parkinson's disease. We designed near-infrared fluorescence dopamine-responsive nanoprobes (DRNs) for brain activity imaging during drug abuse and addiction process. On the basis of light-induced electron transfer between DRNs and dopamine and molecular wire effect of the DRNs, we can track the dynamical change of the neurotransmitter level in the physiological environment and the releasing of the neurotransmitter in living dopaminergic neurons in response to nicotine stimulation. The functional near-infrared fluorescence imaging can dynamically track the dopamine level in the mice midbrain under normal or drug-activated condition and evaluate the long-term effect of addictive substances to the brain. This strategy has the potential for studying neural activity under physiological condition.

Surface-polariton propagation for scanning near-field optical microscopy application.

PubMed

Keilmann, F

1999-01-01

Surface plasmon-, phonon- and exciton-polaritons exist on specific materials in specific spectral regions. We assess the properties of such travelling surface-bound electromagnetic waves relevant for scanning near-field optical microscopy applications, i.e. the tightness of surface binding, the attenuation, the phase velocity and the coupling with free-space electromagnetic waves. These quantities can be directly determined by photographic imaging of surface plasmon- and surface phonon-polaritons, in both the visible and mid-infared regions. Focusing of mid-infrared surface plasmons is demonstrated. Surface waveguides to transport and focus photons to the tip of a scanning near-field probe are outlined.

Mass constraints to Sco X-1 from Bowen fluorescence and deep near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Mata Sánchez, D.; Muñoz-Darias, T.; Casares, J.; Steeghs, D.; Ramos Almeida, C.; Acosta Pulido, J. A.

2015-04-01

More than 50 years after the dawn of X-ray astronomy, the dynamical parameters of the prototypical X-ray binary Sco X-1 are still unknown. We combine a Monte Carlo analysis, which includes all the previously known orbital parameters of the system, along with the K-correction to set dynamical constraints to the masses of the compact object (M1 < 1.73 M⊙) and the companion star (0.28 M⊙ < M2 < 0.70 M⊙). For the case of a canonical neutron star mass of M1 ˜ 1.4 M⊙, the orbital inclination is found to be lower than 40°. We also present the best near-infrared spectrum of the source to date. There is no evidence of donor star features on it, but we are able to constrain the veiling factor as a function of the spectral type of the secondary star. The combination of both techniques restricts the spectral type of the donor to be later than K4 and luminosity class IV. It also constrains the contribution of the companion light to the infrared emission of Sco X-1 to be lower than 33 per cent. This implies that the accretion related luminosity of the system in the K band is larger than ˜4 × 1035 erg s-1.

Near-infrared face recognition utilizing open CV software

NASA Astrophysics Data System (ADS)

Sellami, Louiza; Ngo, Hau; Fowler, Chris J.; Kearney, Liam M.

2014-06-01

Commercially available hardware, freely available algorithms, and authors' developed software are synergized successfully to detect and recognize subjects in an environment without visible light. This project integrates three major components: an illumination device operating in near infrared (NIR) spectrum, a NIR capable camera and a software algorithm capable of performing image manipulation, facial detection and recognition. Focusing our efforts in the near infrared spectrum allows the low budget system to operate covertly while still allowing for accurate face recognition. In doing so a valuable function has been developed which presents potential benefits in future civilian and military security and surveillance operations.

[Development of a Surgical Navigation System with Beam Split and Fusion of the Visible and Near-Infrared Fluorescence].

PubMed

Yang, Xiaofeng; Wu, Wei; Wang, Guoan

2015-04-01

This paper presents a surgical optical navigation system with non-invasive, real-time, and positioning characteristics for open surgical procedure. The design was based on the principle of near-infrared fluorescence molecular imaging. The in vivo fluorescence excitation technology, multi-channel spectral camera technology and image fusion software technology were used. Visible and near-infrared light ring LED excitation source, multi-channel band pass filters, spectral camera 2 CCD optical sensor technology and computer systems were integrated, and, as a result, a new surgical optical navigation system was successfully developed. When the near-infrared fluorescence was injected, the system could display anatomical images of the tissue surface and near-infrared fluorescent functional images of surgical field simultaneously. The system can identify the lymphatic vessels, lymph node, tumor edge which doctor cannot find out with naked eye intra-operatively. Our research will guide effectively the surgeon to remove the tumor tissue to improve significantly the success rate of surgery. The technologies have obtained a national patent, with patent No. ZI. 2011 1 0292374. 1.

A near-infrared tip-tilt sensor for the Keck I laser guide star adaptive optics system

NASA Astrophysics Data System (ADS)

Wizinowich, Peter; Smith, Roger; Biasi, Roberto; Cetre, Sylvain; Dekany, Richard; Femenia-Castella, Bruno; Fucik, Jason; Hale, David; Neyman, Chris; Pescoller, Dietrich; Ragland, Sam; Stomski, Paul; Andrighettoni, Mario; Bartos, Randy; Bui, Khanh; Cooper, Andrew; Cromer, John; van Dam, Marcos; Hess, Michael; James, Ean; Lyke, Jim; Rodriguez, Hector; Stalcup, Thomas

2014-07-01

The sky coverage and performance of laser guide star (LGS) adaptive optics (AO) systems is limited by the natural guide star (NGS) used for low order correction. This limitation can be dramatically reduced by measuring the tip and tilt of the NGS in the near-infrared where the NGS is partially corrected by the LGS AO system and where stars are generally several magnitudes brighter than at visible wavelengths. We present the design of a near-infrared tip-tilt sensor that has recently been integrated with the Keck I telescope's LGS AO system along with some initial on-sky results. The implementation involved modifications to the AO bench, real-time control system, and higher level controls and operations software that will also be discussed. The tip-tilt sensor is a H2RG-based near-infrared camera with 0.05 arc second pixels. Low noise at high sample rates is achieved by only reading a small region of interest, from 2×2 to 16×16 pixels, centered on an NGS anywhere in the 100 arc second diameter field. The sensor operates at either Ks or H-band using light reflected by a choice of dichroic beamsplitters located in front of the OSIRIS integral field spectrograph.

Development of a neurofeedback protocol targeting the frontal pole using near-infrared spectroscopy.

PubMed

Kinoshita, Akihide; Takizawa, Ryu; Yahata, Noriaki; Homae, Fumitaka; Hashimoto, Ryuichiro; Sakakibara, Eisuke; Kawasaki, Shingo; Nishimura, Yukika; Koike, Shinsuke; Kasai, Kiyoto

2016-11-01

Neurofeedback has been studied with the aim of controlling cerebral activity. Near-infrared spectroscopy is a non-invasive neuroimaging technique used for measuring hemoglobin concentration changes in cortical surface areas with high temporal resolution. Thus, near-infrared spectroscopy may be useful for neurofeedback, which requires real-time feedback of repeated brain activation measurements. However, no study has specifically targeted neurofeedback, using near-infrared spectroscopy, in the frontal pole cortex. We developed an original near-infrared spectroscopy neurofeedback system targeting the frontal pole cortex. Over a single day of testing, each healthy participant (n = 24) received either correct or incorrect (Sham) feedback from near-infrared spectroscopy signals, based on a crossover design. Under correct feedback conditions, significant activation was observed in the frontal pole cortex (P = 0.000073). Additionally, self-evaluation of control and metacognitive beliefs were associated with near-infrared spectroscopy signals (P = 0.006). The neurofeedback system developed in this study might be useful for developing control of frontal pole cortex activation. © 2016 The Authors. Psychiatry and Clinical Neurosciences © 2016 Japanese Society of Psychiatry and Neurology.

NEAR-INFRARED POLARIZATION SOURCE CATALOG OF THE NORTHEASTERN REGIONS OF THE LARGE MAGELLANIC CLOUD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jaeyeong; Pak, Soojong; Jeong, Woong-Seob

2016-01-15

We present a near-infrared band-merged photometric and polarimetric catalog for the 39′ × 69′ fields in the northeastern part of the Large Magellanic Cloud (LMC), which were observed using SIRPOL, an imaging polarimeter of the InfraRed Survey Facility. This catalog lists 1858 sources brighter than 14 mag in the H band with a polarization signal-to-noise ratio greater than three in the J, H, or K{sub s} bands. Based on the relationship between the extinction and the polarization degree, we argue that the polarization mostly arises from dichroic extinctions caused by local interstellar dust in the LMC. This catalog allows usmore » to map polarization structures to examine the global geometry of the local magnetic field, and to show a statistical analysis of the polarization of each field to understand its polarization properties. In the selected fields with coherent polarization position angles, we estimate magnetic field strengths in the range of 3−25 μG using the Chandrasekhar–Fermi method. This implies the presence of large-scale magnetic fields on a scale of around 100 parsecs. When comparing mid- and far-infrared dust emission maps, we confirmed that the polarization patterns are well aligned with molecular clouds around the star-forming regions.« less

Development of a Field-Portable Near-Infrared Water-Cement Ratio Meter. Phase I: Investigation of Spectral Feasibility

DOT National Transportation Integrated Search

1999-06-25

In order to accurately predict the strength and durability of an adequately mixed and compacted concrete mix it is useful, if not necessary, to know the water-cement ratio of the fresh concrete mix. In this work near-infrared reflection spectroscopy ...

Near-infrared sensitive photorefractive device using polymer dispersed liquid crystal and BSO:Ru hybrid structure.

PubMed

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

2014-06-01

A near-infrared sensitive hybrid device, based on a Ru-doped BSO photorefractive substrate and polymer dispersed liquid crystal (PDLC) layer, is reported. It is found that the photoexcited charge carriers generated in the BSO:Ru substrate create an optically induced space charge field, sufficient to penetrate into the PDLC layer and to re-orient the LC molecules inside the droplets. Beam-coupling measurements at the Bragg regime are performed showing prospective amplification values and high spatial resolution. The proposed structure does not require indium tin oxide (ITO) contacts and alignment layers. Such a device allows all the processes to be controlled by light, thus opening further potential for real-time image processing at the near-infrared range.

A near-infrared SETI experiment: commissioning, data analysis, and performance results

NASA Astrophysics Data System (ADS)

Maire, Jérôme; Wright, Shelley A.; Dorval, Patrick; Drake, Frank D.; Duenas, Andres; Isaacson, Howard; Marcy, Geoffrey W.; Siemion, Andrew; Stone, Remington P. S.; Tallis, Melisa; Treffers, Richard R.; Werthimer, Dan

2016-08-01

Over the last two decades, Optical Search for Extra-Terrestrial Intelligence experiments have been conducted to search for either continuous or pulsed visible-light laser beacons that could be used for interstellar communication or energy transmission. Near-infrared offers a compelling window for signal transmission since there is a decrease in interstellar extinction and Galactic background compared to optical wavelengths. An innovative Near-InfraRed and Optical SETI (NIROSETI) instrument has been designed and constructed to take advantage of a new generation of fast (> 1 Ghz) low-noise near-infrared avalanche photodiodes to search for nanosecond pulsed near-infrared (850 - 1650 nm) pulses. The instrument was successfully installed and commissioned at the Nickel (1m) telescope at Lick Observatory in March 2015. We will describe the overall design of the instrument with a focus on methods developed for data acquisition and reduction for near-infrared SETI. Time and height analyses of the pulses produced by the detectors are performed to search for periodicity and coincidences in the signals. We will further discuss our NIROSETI survey plans.

Safety assessment of near infrared light emitting diodes for diffuse optical measurements

PubMed Central

Bozkurt, Alper; Onaral, Banu

2004-01-01

Background Near infrared (NIR) light has been used widely to monitor important hemodynamic parameters in tissue non-invasively. Pulse oximetry, near infrared spectroscopy, and diffuse optical tomography are examples of such NIR light-based applications. These and other similar applications employ either lasers or light emitting diodes (LED) as the source of the NIR light. Although the hazards of laser sources have been addressed in regulations, the risk of LED sources in such applications is still unknown. Methods Temperature increase of the human skin caused by near infrared LED has been measured by means of in-vivo and in-vitro experiments. Effects of the conducted and radiated heat in the temperature increase have been analyzed separately. Results Elevations in skin temperature up to 10°C have been observed. The effect of radiated heat due to NIR absorption is low – less than 0.5°C – since emitted light power is comparable to the NIR part of sunlight. The conducted heat due to semiconductor junction of the LED can cause temperature increases up to 9°C. It has been shown that adjusting operational parameters by amplitude modulating or time multiplexing the LED decreases the temperature increase of the skin significantly. Conclusion In this study, we demonstrate that the major risk source of the LED in direct contact with skin is the conducted heat of the LED semiconductor junction, which may cause serious skin burns. Adjusting operational parameters by amplitude modulating or time multiplexing the LED can keep the LED within safe temperature ranges. PMID:15035670

Global View of Earth in the Near-Infrared

NASA Image and Video Library

1996-02-08

This near-infrared photograph of the Earth was taken by the Galileo spacecraft at 6:07 a.m. PST on Dec. 11, 1990, at a range of about 1.32 million miles. South America is prominent near the center. http://photojournal.jpl.nasa.gov/catalog/PIA00226

The mass-metallicity relation of AKARI-FMOS infrared galaxies at z ∼ 0.88 in the AKARI North Ecliptic Pole Deep Survey Field

NASA Astrophysics Data System (ADS)

Oi, Nagisa; Goto, Tomotsugu; Malkan, Matthew; Pearson, Chris; Matsuhara, Hideo

2017-08-01

The mass, metallicity, and star formation rate (SFR) of a galaxy are crucial parameters in understanding galaxy formation and evolution. However, the relation between these parameters, (i.e., the fundamental relation) is still a matter of debate for luminous infrared (IR) galaxies, which carry a bulk of the SFR budget of the universe at z ∼ 1. We have investigated the relation among stellar mass, gas-phase oxygen abundance, and SFR of the Japanese infrared satellite AKARI-detected mid-IR galaxies at z ∼ 0.88 in the AKARI north ecliptic pole deep field. We observed ∼350 AKARI sources with Subaru/Fiber Multi Object Spectrograph near-IR spectrograph, and detected confirmed Hα emission lines from 25 galaxies and expected Hα emission lines from 44 galaxies. The SFRHα, IR of our sample is almost constant (〈SFRHα, IR〉 = ∼ 25 M⊙ yr - 1) over the stellar mass range of our sample. Compared with main-sequence (MS) galaxies at a similar redshift range (z ∼ 0.78), the average SFR of our detected sample is comparable for massive galaxies ( ∼ 1010.58 M⊙), while higher by ∼0.6 dex for less massive galaxies ( ∼ 1010.05 M⊙). We measure metallicities from the [N II]/Hα emission line ratio. We find that the mass-metallicity relation of our individually measured sources agrees with that for optically-selected star-forming galaxies at z ∼ 0.1, while metallicities of stacked spectra agree with that of MS galaxies at z ∼ 0.78. Considering the high SFR of individually measured sources, the fundamental metallicity relation (FMR) of the IR galaxies is different from that at z ∼ 0.1. However, on the mass-metallicity plane, they are consistent with the MS galaxies, highlighting the higher SFR of the IR galaxies. This suggests that the evolutionary path of our infrared galaxies is different from that of MS galaxies. A possible physical interpretation includes that the star-formation activities of IR galaxies at z ∼ 0.88 in our sample are enhanced by

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.

Status and new developments with the Keck I near-infrared tip-tilt sensor

NASA Astrophysics Data System (ADS)

Femenía Castellá, Bruno; Wizinowich, Peter; Rampy, Rachel; Cetre, Sylvain; Lilley, Scott; Lyke, Jim; Ragland, Sam; Stomski, Paul; van Dam, Marcos

2016-07-01

The sky coverage and performance of Laser Guide Star (LGS) adaptive optics (AO) systems is limited by the Natural Guide Star (NGS) used for low order correction (tip-tilt and defocus modes). This limitation can be reduced by measuring image motion of the NGS in the near-infrared where it is partially corrected by the LGS AO system and where stars are generally several magnitudes brighter than at visible wavelengths. We have integrated a Near-InfraRed Tip-Tilt Sensor (NIRTTS) with the Keck I telescopes LGS AO system. The sensor is a H2RG-based near-infrared camera with 0.05 arcsecond pixels. Low noise at high sample rates is achieved by only reading a small region of interest, from 2x2 to 16x16 pixels, centered on an NGS anywhere in an 100 arc second diameter field. The sensor operates at either Ks or H-band using light reflected by a choice of dichroic beam-splitters located in front of the OSIRIS integral field spectrograph. The implementation of the NIRTTS involved modifications to the AO bench, real-time control system, higher-level controls and operations software. NIRTTS is nearly ready for science operation in shared-risk mode. We are also implementing a number of enhancements to the NIRTTS system which involve substantial changes to the operations software. This work presents an update of the work performed since the NIRTTS system was reported in Ref. 1 and Ref. 2.

Application of near infrared spectroscopy to the analysis and fast quality assessment of traditional Chinese medicinal products

PubMed Central

Zhang, Chao; Su, Jinghua

2014-01-01

Near infrared spectroscopy (NIRS) has been widely applied in both qualitative and quantitative analysis. There is growing interest in its application to traditional Chinese medicine (TCM) and a review of recent developments in the field is timely. To present an overview of recent applications of NIRS to the identification, classification and analysis of TCM products, studies describing the application of NIRS to TCM products are classified into those involving qualitative and quantitative analysis. In addition, the application of NIRS to the detection of illegal additives and the rapid assessment of quality of TCMs by fast inspection are also described. This review covers over 100 studies emphasizing the application of NIRS in different fields. Furthermore, basic analytical principles and specific examples are used to illustrate the feasibility and effectiveness of NIRS in pattern identification. NIRS provides an effective and powerful tool for the qualitative and quantitative analysis of TCM products. PMID:26579382

Deep CFHT Y-band Imaging of VVDS-F22 Field. I. Data Products and Photometric Redshifts

NASA Astrophysics Data System (ADS)

Liu, Dezi; Yang, Jinyi; Yuan, Shuo; Wu, Xue-Bing; Fan, Zuhui; Shan, Huanyuan; Yan, Haojing; Zheng, Xianzhong

2017-02-01

We present our deep Y-band imaging data of a 2 square degree field within the F22 region of the VIMOS VLT Deep Survey. The observations were conducted using the WIRCam instrument mounted at the Canada-France-Hawaii Telescope (CFHT). The total on-sky time was 9 hr, distributed uniformly over 18 tiles. The scientific goals of the project are to select faint quasar candidates at redshift z> 2.2 and constrain the photometric redshifts for quasars and galaxies. In this paper, we present the observation and the image reduction, as well as the photometric redshifts that we derived by combining our Y-band data with the CFHTLenS {u}* g\\prime r\\prime I\\prime z\\prime optical data and UKIDSS DXS JHK near-infrared data. With the J-band image as a reference, a total of ˜80,000 galaxies are detected in the final mosaic down to a Y-band 5σ point-source limiting depth of 22.86 mag. Compared with the ˜3500 spectroscopic redshifts, our photometric redshifts for galaxies with z< 1.5 and I\\prime ≲ 24.0 mag have a small systematic offset of | {{Δ }}z| ≲ 0.2, 1σ scatter 0.03< {σ }{{Δ }z}< 0.06, and less than 4.0% of catastrophic failures. We also compare with the CFHTLenS photometric redshifts and find that ours are more reliable at z≳ 0.6 because of the inclusion of the near-infrared bands. In particular, including the Y-band data can improve the accuracy at z˜ 1.0{--}2.0 because the location of the 4000 Å break is better constrained. The Y-band images, the multiband photometry catalog, and the photometric redshifts are released at http://astro.pku.edu.cn/astro/data/DYI.html.

The FLARE mission: deep and wide-field 1-5um imaging and spectroscopy for the early universe: a proposal for M5 cosmic vision call

NASA Astrophysics Data System (ADS)

Burgarella, D.; Levacher, P.; Vives, S.; Dohlen, K.; Pascal, S.

2016-07-01

FLARE (First Light And Reionization Explorer) is a space mission that will be submitted to ESA (M5 call). Its primary goal (~80% of lifetime) is to identify and study the universe before the end of the reionization at z > 6. A secondary objective (~20% of lifetime) is to survey star formation in the Milky Way. FLARE's strategy optimizes the science return: imaging and spectroscopic integral-field observations will be carried out simultaneously on two parallel focal planes and over very wide instantaneous fields of view. FLARE will help addressing two of ESA's Cosmic Vision themes: a) << How did the universe originate and what is it made of? » and b) « What are the conditions for planet formation and the emergence of life? >> and more specifically, << From gas and dust to stars and planets >>. FLARE will provide to the ESA community a leading position to statistically study the early universe after JWST's deep but pin-hole surveys. Moreover, the instrumental development of wide-field imaging and wide-field integral-field spectroscopy in space will be a major breakthrough after making them available on ground-based telescopes.

Wide-Field Infrared Survey Explorer Observations of Young Stellar Objects in the Lynds 1509 Dark Cloud in Auriga

NASA Technical Reports Server (NTRS)

Liu, Wilson M.; Padgett, Deborah L.; Terebey, Susan; Angione, John; Rebull, Luisa M.; McCollum, Bruce; Fajardo-Acosta, Sergio; Leisawitz, David

2015-01-01

The Wide-Field Infrared Survey Explorer (WISE) has uncovered a striking cluster of young stellar object (YSO) candidates associated with the L1509 dark cloud in Auriga. The WISE observations, at 3.4, 4.6, 12, and 22 microns, show a number of objects with colors consistent with YSOs, and their spectral energy distributions suggest the presence of circumstellar dust emission, including numerous Class I, flat spectrum, and Class II objects. In general, the YSOs in L1509 are much more tightly clustered than YSOs in other dark clouds in the Taurus-Auriga star forming region, with Class I and flat spectrum objects confined to the densest aggregates, and Class II objects more sparsely distributed. We estimate a most probable distance of 485-700 pc, and possibly as far as the previously estimated distance of 2 kpc.

Near-field nano-Raman imaging of Si device structures

NASA Astrophysics Data System (ADS)

Atesang, Jacob; Geer, Robert

2005-05-01

Apertureless-based, near-field Raman imaging holds the potential for nanoscale stress metrology in emerging Si devices. Preliminary application of near-field Raman imaging on Si device structures has demonstrated the potential for stress measurements. However, detailed investigations have not been published regarding the effect of tip radius on observed near-field enhancement. Such investigations are important to understand the fundamental limits regarding the signal-to-noise ratio of the measurement and the spatial resolution that can potentially be achieved before wide application to semiconductor metrology can be considered. Investigations are presented into near-field enhancement of Raman scattering from Si device structures using a modified near-field optical microscope (NSOM). The nano-Raman system utilizes an off-axis (45°) backscattering NSOM geometry with free-space collection optics. The spectroscopic configuration utilizes a single-bounce spectrometer incorporating a holographic notch filter assembly utilized as a secondary beam-splitter for an apertureless backscattering collection geometry. Near-field enhancement is observed for both Al- and Ag-coated probes. An inverse square power-law relationship is observed between near-field enhancement factor and tip radius.

Dielectric magnetic microparticles as photomagnonic cavities: Enhancing the modulation of near-infrared light by spin waves

NASA Astrophysics Data System (ADS)

Almpanis, Evangelos

2018-05-01

The coupling between spin waves and optical Mie resonances inside a dielectric magnetic spherical particle, which acts simultaneously as a photonic and magnonic (photomagnonic) cavity, is investigated by means of numerical calculations accurate to arbitrary order in the magnetooptical coupling coefficient. Isolated dielectric magnetic particles with diameters of just a few microns support high-Q optical Mie resonances at near-infrared frequencies and localized spin waves, providing an ultrasmall and compact platform in the emerging field of cavity optomagnonics. Our results predict the occurrence of strong interaction effects, beyond the linear-response approximation, which lead to enhanced modulation of near-infrared light by spin waves through multimagnon absorption and emission mechanisms.

[Application progress on near infrared spectroscopy in quality control and process monitoring of traditional Chinese medicine].

PubMed

Li, Wenlong; Qu, Haibin

2017-01-25

The industry of traditional Chinese medicine (TCM) encounters problems like quality fluctuation of raw materials and unstandardized production process. Near infrared (NIR) spectroscopy technology is widely used in quality control of TCM because of its abundant information, fast and nondestructive characters. The main applications include quantitative analysis of Chinese medicinal materials, intermediates and Chinese patent medicines; the authenticity of TCM, species, origins and manufacturers; monitoring and control of the extraction, alcohol precipitation, column chromatography and blending process. This article reviews the progress on the application of NIR spectroscopy technology in TCM field. In view of the problems existing in the application, the article proposes that the standardization of NIR analysis method should be developed according to specific characteristics of TCM, which will promote the application of NIR technology in the TCM industry.

Neutron-capture element abundances in the planetary nebula NGC 5315 from deep optical and near-infrared spectrophotometry★†

NASA Astrophysics Data System (ADS)

Madonna, S.; García-Rojas, J.; Sterling, N. C.; Delgado-Inglada, G.; Mesa-Delgado, A.; Luridiana, V.; Roederer, I. U.; Mashburn, A. L.

2017-10-01

We analyse the chemical composition of the planetary nebula (PN) NGC 5315, through high-resolution (R ˜ 40000) optical spectroscopy with Ultraviolet-Visual Echelle Spectrograph at the Very Large Telescope, and medium-resolution (R ˜ 4800) near-infrared spectroscopy with Folded-port InfraRed Echellette at Magellan Baade Telescope, covering a wide spectral range from 0.31 to 2.50 μm. The main aim of this work is to investigate neutron (n)-capture element abundances to study the operation of the slow n-capture ('s-process') in the asymptotic giant branch (AGB) progenitor of NGC 5315. We detect more than 700 emission lines, including ions of the n-capture elements Se, Kr, Xe and possibly Br. We compute physical conditions from a large number of diagnostic line ratios, and derive ionic abundances for species with available atomic data. The total abundances are computed using recent ionization correction factors (ICFs) or by summing ionic abundances. Total abundances of common elements are in good agreement with previous work on this object. Based on our abundance analysis of NGC 5315, including the lack of s-process enrichment, we speculate that the most probable evolutionary scenario is that the progenitor star is in a binary system as hinted at by radial velocity studies, and interactions with its companion truncated the AGB before s-process enrichment could occur. However there are other two possible scenarios for its evolution, that cannot be ruled out: (I) the progenitor is a low-mass single star that did not undergo third dredge-up; (II) the progenitor star of NGC 5315 had an initial mass of 3-5 M⊙, and any s-process enhancements were heavily diluted by the massive envelope during the AGB phase.

Imaging of tumor hypermetabolism with near-infrared fluorescence contrast agents

NASA Astrophysics Data System (ADS)

Chen, Yu; Zheng, Gang; Zhang, Zhihong; Blessington, Dana; Intes, Xavier; Achilefu, Samuel I.; Chance, Britton

2004-08-01

We have developed a high sensitivity near-infrared (NIR) optical imaging system for non-invasive cancer detection through molecular labeled fluorescent contrast agents. Near-infrared (NIR) imaging can probe tissue deeply thus possess the potential for non-invasively detection of breast or lymph node cancer. Recent developments in molecular beacons can selectively label various pre-cancer/cancer signatures and provide high tumor to background contrast. To increase the sensitivity in detecting fluorescent photons and the accuracy of localization, phase cancellation (in- and anti-phase) device is employed. This frequency-domain system utilizes the interference-like pattern of diffuse photon density wave to achieve high detection sensitivity and localization accuracy for the fluorescent heterogeneity embedded inside the scattering media. The opto-electronic system consists of the laser sources, fiber optics, interference filter to select the fluorescent photons and the high sensitivity photon detector (photomultiplier tube). The source-detector pair scans the tissue surface in multiple directions and the two-dimensional localization image can be obtained using goniometric reconstruction. In vivo measurements with tumor-bearing mouse model using the novel Cypate-mono-2-deoxy-glucose (Cypate-2-D-Glucosamide) fluorescent contrast agent, which targets the enhanced tumor glycolysis, demonstrated the feasibility on detection of 2 cm deep subsurface tumor in the tissue-like medium, with a localization accuracy within 2 ~ 3 mm. This instrument has the potential for tumor diagnosis and imaging, and the accuracy of the localization suggests that this system could help to guide the clinical fine-needle biopsy. This portable device would be complementary to X-ray mammogram and provide add-on information on early diagnosis and localization of early breast tumor.

Near-infrared spatially resolved spectroscopy of (136108) Haumea's multiple system

NASA Astrophysics Data System (ADS)

Gourgeot, F.; Carry, B.; Dumas, C.; Vachier, F.; Merlin, F.; Lacerda, P.; Barucci, M. A.; Berthier, J.

2016-08-01

Context. The transneptunian region of the solar system is populated by a wide variety of icy bodies showing great diversity in orbital behavior, size, surface color, and composition. Aims: The dwarf planet (136108) Haumea is among the largest transneptunian objects (TNOs) and is a very fast rotator (~3.9 h). This dwarf planet displays a highly elongated shape and hosts two small moons that are covered with crystalline water ice, similar to their central body. A particular region of interest is the Dark Red Spot (DRS) identified on the surface of Haumea from multiband light-curve analysis (Lacerda et al. 2008). Haumea is also known to be the largest member of the sole TNO family known to date, and an outcome of a catastrophic collision that is likely responsible for the unique characteristics of Haumea. Methods: We report here on the analysis of a new set of near-infrared Laser Guide Star assisted observations of Haumea obtained with the Integral Field Unit (IFU) Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) at the European Southern Observatory (ESO) Very Large Telescope (VLT) Observatory. Combined with previous data published by Dumas et al. (2011), and using light-curve measurements in the optical and far infrared to associate each spectrum with its corresponding rotational phase, we were able to carry out a rotationally resolved spectroscopic study of the surface of Haumea. Results: We describe the physical characteristics of the crystalline water ice present on the surface of Haumea for both regions, in and out of the DRS, and analyze the differences obtained for each individual spectrum. The presence of crystalline water ice is confirmed over more than half of the surface of Haumea. Our measurements of the average spectral slope (1.45 ± 0.82% by 100 nm) confirm the redder characteristic of the spot region. Detailed analysis of the crystalline water-ice absorption bands do not show significant differences between the DRS and the

Comparison of Two Methodologies for Calibrating Satellite Instruments in the Visible and Near-Infrared

NASA Technical Reports Server (NTRS)

Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Turpie, Kevin; Moyer, David; DeLuccia, Frank; Moeller, Christopher

2015-01-01

Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as lamp-illuminated integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered.

Comparison of two methodologies for calibrating satellite instruments in the visible and near infrared

PubMed Central

Barnes, Robert A.; Brown, Steven W.; Lykke, Keith R.; Guenther, Bruce; Butler, James J.; Schwarting, Thomas; Moyer, David; Turpie, Kevin; DeLuccia, Frank; Moeller, Christopher

2016-01-01

Traditionally, satellite instruments that measure Earth-reflected solar radiation in the visible and near infrared wavelength regions have been calibrated for radiance responsivity in a two-step method. In the first step, the relative spectral response (RSR) of the instrument is determined using a nearly monochromatic light source such as a lamp-illuminated monochromator. These sources do not typically fill the field-of-view of the instrument nor act as calibrated sources of light. Consequently, they only provide a relative (not absolute) spectral response for the instrument. In the second step, the instrument views a calibrated source of broadband light, such as a lamp-illuminated integrating sphere. The RSR and the sphere absolute spectral radiance are combined to determine the absolute spectral radiance responsivity (ASR) of the instrument. More recently, a full-aperture absolute calibration approach using widely tunable monochromatic lasers has been developed. Using these sources, the ASR of an instrument can be determined in a single step on a wavelength-by-wavelength basis. From these monochromatic ASRs, the responses of the instrument bands to broadband radiance sources can be calculated directly, eliminating the need for calibrated broadband light sources such as integrating spheres. In this work, the traditional broadband source-based calibration of the Suomi National Preparatory Project (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) sensor is compared with the laser-based calibration of the sensor. Finally, the impact of the new full-aperture laser-based calibration approach on the on-orbit performance of the sensor is considered. PMID:26836861

Near-infrared spectra of the Martian surface: Reading between the lines

NASA Technical Reports Server (NTRS)

Crisp, D.; Bell, J. F., III

1993-01-01

Moderate-resolution near-infrared (NIR) spectra of Mars have been widely used in studies of the Martian surface because many candidate surface materials have distinctive absorption features at these wavelengths. Recent advances in NIR detector technology and instrumentation have also encouraged studies in this spectral region. The use of moderate spectral resolution has often been justified for NIR surface observations because the spectral features produced by most surface materials are relatively broad, and easily discriminated at this resolution. In spite of this, NIR spectra of Mars are usually very difficult to interpret quantitatively. One problem is that NIR surface absorption features are often only a few percent deep, requiring observations with great signal-to-noise ratios. A more significant problem is that gases in the Martian atmosphere contribute numerous absorption features at these wavelengths. Ground-based observers must also contend with variable absorption by several gases in the Earth's atmosphere (H2O, CO2, O3, N2O, CH4, O2). The strong CO2 bands near 1.4, 1.6, 2.0, 2.7, 4.3, and 4.8 micrometers largely preclude the analysis of surface spectral features at these wavelengths. Martian atmospheric water vapor also contributes significant absorption near 1.33, 1.88, and 2.7 micrometers, but water vapor in the Earth's atmosphere poses a much larger problem to ground-based studies of these spectral regions. The third most important NIR absorber in the Martian atmosphere is CO. This gas absorbs most strongly in the relatively-transparent spectral windows near 4.6 and 2.3 micrometers. It also produces 1-10 percent absorption in the solar spectrum at these NIR wavelengths. This solar CO absorption cannot be adequately removed by dividing the Martian spectrum by that of a star, as is commonly done to calibrate ground-based spectroscopic observations, because most stars do not have identical amounts of CO absorption in their spectra. Here, we describe tow

Studying extragalactic background fluctuations with the Cosmic Infrared Background ExpeRiment 2 (CIBER-2)

NASA Astrophysics Data System (ADS)

Lanz, Alicia; Arai, Toshiaki; Battle, John; Bock, James; Cooray, Asantha; Hristov, Viktor; Korngut, Phillip; Lee, Dae Hee; Mason, Peter; Matsumoto, Toshio; Matsuura, Shuji; Morford, Tracy; Onishi, Yosuke; Shirahata, Mai; Tsumura, Kohji; Wada, Takehiko; Zemcov, Michael

2014-08-01

Fluctuations in the extragalactic background light trace emission from the history of galaxy formation, including the emission from the earliest sources from the epoch of reionization. A number of recent near-infrared measure- ments show excess spatial power at large angular scales inconsistent with models of z < 5 emission from galaxies. These measurements have been interpreted as arising from either redshifted stellar and quasar emission from the epoch of reionization, or the combined intra-halo light from stars thrown out of galaxies during merging activity at lower redshifts. Though astrophysically distinct, both interpretations arise from faint, low surface brightness source populations that are difficult to detect except by statistical approaches using careful observations with suitable instruments. The key to determining the source of these background anisotropies will be wide-field imaging measurements spanning multiple bands from the optical to the near-infrared. The Cosmic Infrared Background ExpeRiment 2 (CIBER-2) will measure spatial anisotropies in the extra- galactic infrared background caused by cosmological structure using six broad spectral bands. The experiment uses three 2048 x 2048 Hawaii-2RG near-infrared arrays in three cameras coupled to a single 28.5 cm telescope housed in a reusable sounding rocket-borne payload. A small portion of each array will also be combined with a linear-variable filter to make absolute measurements of the spectrum of the extragalactic background with high spatial resolution for deep subtraction of Galactic starlight. The large field of view and multiple spectral bands make CIBER-2 unique in its sensitivity to fluctuations predicted by models of lower limits on the luminosity of the first stars and galaxies and in its ability to distinguish between primordial and foreground anisotropies. In this paper the scientific motivation for CIBER-2 and details of its first flight instrumentation will be discussed, including

The FUV to Near-IR Morphologies of Luminous Infrared Galaxies in the Goals Sample

NASA Astrophysics Data System (ADS)

Petty, S. M.; Armus, L.; Charmandaris, V.; Evans, A. S.; Le Floc'h, E.; Bridge, C.; Díaz-Santos, T.; Howell, J. H.; Inami, H.; Psychogyios, A.; Stierwalt, S.; Surace, J. A.

2014-12-01

We compare the morphologies of a sample of 20 luminous infrared galaxies (LIRGs) from the Great Observatories All-sky LIRG Survey (GOALS) in the FUV, B, I, and H bands, using the Gini (G) and M20 parameters to quantitatively estimate the distribution and concentration of flux as a function of wavelength. Hubble Space Telescope (HST) images provide an average spatial resolution of ˜ 80 pc. While our LIRGs can be reliably classified as mergers across the entire range of wavelengths studied here, there is a clear shift toward more negative M20 (more bulge-dominated) and a less significant decrease in G values at longer wavelengths. We find no correlation between the derived FUV G-M20 parameters and the global measures of the IR to FUV flux ratio (IRX). Given the fine resolution in our HST data, this suggests either that the UV morphology and IRX are correlated on very small scales, or that the regions emitting the bulk of the IR emission emit almost no FUV light. We use our multi-wavelength data to simulate how merging LIRGs would appear from z˜ 0.5-3 in deep optical and near-infrared images such as the Hubble Ultra-Deep Field, and use these simulations to measure the G-M20 at these redshifts. Our simulations indicate a noticeable decrease in G, which flattens at z≥slant 2 by as much as 40%, resulting in mis-classifying our LIRGs as disk-like, even in the rest-frame FUV. The higher redshift values of M20 for the GOALS sources do not appear to change more than about 10% from the values at z˜ 0. The change in G-M20 is caused by the surface brightness dimming of extended tidal features and asymmetries, and also the decreased spatial resolution which reduced the number of individual clumps identified. This effect, seen as early as z˜ 0.5, could easily lead to an underestimate of the number of merging galaxies at high-redshift in the rest-frame FUV.

Research on capability of detecting ballistic missile by near space infrared system

NASA Astrophysics Data System (ADS)

Lu, Li; Sheng, Wen; Jiang, Wei; Jiang, Feng

2018-01-01

The infrared detection technology of ballistic missile based on near space platform can effectively make up the shortcomings of high-cost of traditional early warning satellites and the limited earth curvature of ground-based early warning radar. In terms of target detection capability, aiming at the problem that the formula of the action distance based on contrast performance ignores the background emissivity in the calculation process and the formula is only valid for the monochromatic light, an improved formula of the detecting range based on contrast performance is proposed. The near space infrared imaging system parameters are introduced, the expression of the contrastive action distance formula based on the target detection of the near space platform is deduced. The detection range of the near space infrared system for the booster stage ballistic missile skin, the tail nozzle and the tail flame is calculated. The simulation results show that the near-space infrared system has the best effect on the detection of tail-flame radiation.

Probing the conditions within Photo-dissociation Regions with high resolution near-infrared spectroscopy of UV-excited molecular hydrogen

NASA Astrophysics Data System (ADS)