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1

Cooled echelle grating spectrometer. [for space telescope applications  

NASA Technical Reports Server (NTRS)

A cooled echelle grating spectrometer for detecting wavelengths between one micron and fifteen microns is disclosed. More specifically, the spectrometer has a cross-dispersing grating for ordering infrared energy and an echelle grating for further ordering of the infrared energy. Ordered radiation from the echelle grating is sensed by a detecting means. Also disclosed is use of a Schmidt camera for focusing the further ordered radiation from the echelle grating onto a detector array having individual detectors dispersed on a plane which substantially corresponds to a curved focal plane of the Schmidt camera. A spectrometer constructed according to the teachings of the present invention will continuously cover the spectrum between one micron and fifteen microns and have a resolution of 0.1/cm.

Beer, R. (inventor)

1980-01-01

2

GRIS: The grating infrared spectrometer  

Microsoft Academic Search

The grating infrared spectrometer (GRIS) is an echelle grating, prism cross-dispersed, spectrometer designed for the 2.3-m Steward Observatory telescope. The cross-dispersed format utilizes a Near Infrared Camera and Multi-Object Spectrometer 3 (NICMOS 3) HgCdTe detector array for observations in the 0.86-2.5 micrometer spectral region. An echelle grating, ruled on both sides, provides resolutions of 3449 and 9439 per slit width,

Rodger I. Thompson; Harland W. Epps; Greg Winters; William Womack; Eric Mentzell

1994-01-01

3

Astronomical near-infrared echelle gratings  

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

4

Compact high-resolution spaceborne echelle grating spectrometer with acousto-optical tunable filter based order sorting for the infrared domain from 2.2 to 4.3 mum  

Microsoft Academic Search

A new compact spaceborne high-resolution spectrometer developed for the European Space Agency's Venus Express spacecraft is described. It operates in the IR wavelength range of 2.2 to 4.3 mum and measures absorption spectra of minor constituents in the Venusian atmosphere. It uses a novel echelle grating with a groove density of 4 lines\\/mm in a Littrow configuration in combination with

Dennis Nevejans; Eddy Neefs; Emiel van Ransbeeck; Sophie Berkenbosch; Roland Clairquin; Lieve de Vos; Wouter Moelans; Stijn Glorieux; Ann Baeke; Oleg Korablev; Imant Vinogradov; Yuri Kalinnikov; Benny Bach; Jean-Pierre Dubois; Eric Villard

2006-01-01

5

A Far Infrared Echelle Spectrometer for the Kuiper Airborne Observatory  

NASA Technical Reports Server (NTRS)

A liquid-helium-cooled grating spectrometer (CGS) is being developed as a facility instrument for the Kuiper Airborne Observatory (KAO), primarily to study for infrared lines originating in the interstellar medium. A maximum resolving power of approximately 6000 is achieved by means of a 45 cm long Echelle grating and is optically capable of operating in the spectral range from 25 to 300 microns. An array of detectors is used to simultaneously measure a line and the adjacent continuum from astronomical sources. Currently six detectors allow measurements in the 30 to 120 micron spectral band. The instrument, its operation, and its performance are described.

Erickson, E. F.; Houck, J. R.; Harwit, M. O.; Rank, D. M.; Haas, M. R.; Hollenbach, D. J.; Simpson, J. P.; Augason, G. C.; Mckibbin, D. D.

1984-01-01

6

Optical Alignment and Diffraction Analysis for AIRES: An Airborne Infrared Echelle Spectrometer  

NASA Technical Reports Server (NTRS)

The optical design is presented for a long-slit grating spectrometer known as AIRES (Airborne InfraRed Echelle Spectrometer). The instrument employs two gratings in series: a small order sorter and a large steeply blazed echelle. The optical path includes four pupil and four field stops, including two narrow slits. A detailed diffraction analysis is performed using GLAD by Applied Optics Research to evaluate critical trade-offs between optical throughput, spectral resolution, and system weight and volume. The effects of slit width, slit length, oversizing the second slit relative to the first, on- vs off-axis throughput, and clipping at the pupil stops and other optical elements are discussed.

Haas, Michael R.; Fonda, Mark (Technical Monitor)

2002-01-01

7

Spherical grating spectrometers  

NASA Astrophysics Data System (ADS)

We describe designs for spectrometers employing convex dispersers. The Offner spectrometer was the first such instrument; it has almost exclusively been employed on satellite platforms, and has had little impact on ground-based instruments. We have learned how to fabricate curved Volume Phase Holographic (VPH) gratings and, in contrast to the planar gratings of traditional spectrometers, describe how such devices can be used in optical/infrared spectrometers designed specifically for curved diffraction gratings. Volume Phase Holographic gratings are highly efficient compared to conventional surface relief gratings; they have become the disperser of choice in optical / NIR spectrometers. The advantage of spectrometers with curved VPH dispersers is the very small number of optical elements used (the simplest comprising a grating and a spherical mirror), as well as illumination of mirrors off axis, resulting in greater efficiency and reduction in size. We describe a "Half Offner" spectrometer, an even simpler version of the Offner spectrometer. We present an entirely novel design, the Spherical Transmission Grating Spectrometer (STGS), and discuss exemplary applications, including a design for a double-beam spectrometer without any requirement for a dichroic. This paradigm change in spectrometer design offers an alternative to all-refractive astronomical spectrometer designs, using expensive, fragile lens elements fabricated from CaF2 or even more exotic materials. The unobscured mirror layout avoids a major drawback of the previous generation of catadioptric spectrometer designs. We describe laboratory measurements of the efficiency and image quality of a curved VPH grating in a STGS design, demonstrating, simultaneously, efficiency comparable to planar VPH gratings along with good image quality. The stage is now set for construction of a prototype instrument with impressive performance.

O'Donoghue, Darragh; Clemens, J. Christopher

2014-07-01

8

Integrated Grating Spectrometer  

NASA Technical Reports Server (NTRS)

Proposed integrated grating spectrometer made in waveguide layer on silicon wafer. Occupies area of about 2 centimeters to 2nd power on wafer 0.4 mm thick. Operates in visible spectrum (wavelengths of 400 to 700 nm) and blazed to diffract in first order. Array of integrated grating spectrometers performs spectral analysis of picture elements along line. Optical fiber couples light from each picture element into separate integrated spectrometer. Technique enables continous independent variation, along grating, of pitch, curvature, and blaze angle. Grating designed to have large numerical aperture, zero aberration at two selected wavelengths, and very low aberration at intermediate wavelengths.

Lang, Robert J.

1990-01-01

9

Design considerations for AIRES, an airborne infrared echelle spectrometer for SOFIA  

NASA Technical Reports Server (NTRS)

The airborne infrared echelle spectrometer (AIRES) was proposed as a facility instrument for the stratospheric observatory for infrared astronomy (SOFIA) project. The preliminary AIRES design uses multiple two dimensional detector arrays and a 1.2 m long, 76 deg blaze angle echelle to combine high spectral resolution with diffraction limited imaging in the cross-dispersion direction. A preliminary optical design and the mechanical architecture are presented together with the analysis and prototyping of lightweight aluminum echelles. Instrument efficiencies are calculated and compared for different gratings, and the associated mechanical design tradeoffs are discussed.

Haas, Michael R.; Erickson, Edwin F.; Baltz, James A.; Colgan, Sean W. J.; Lynch, Dana H.; Sablan, Marita

1996-01-01

10

High-Throughput, High-Resolution Echelle Deep-UV Raman Spectrometer  

E-print Network

-phase samples. This bandwidth is comparable to the homogeneous line widths of Raman bands of biological of a single peptide bond for a protein of 100 amino acids. SPECTROMETER DESIGN Figure 1 shows the optical diagram of the Echelle spectrograph we constructed. The spectrograph utilizes two gratings; one regular

Asher, Sanford A.

11

[The echelle grating monochromator's design of pure rotational Raman Lidar].  

PubMed

The pure rotization oal Raman Lidar temperature measurement system usually retrieve atmospheric temperature according to the echo signal of high and low-level quantum numbers of N2 moleules. An effective method to detect the rotational Raman spectrum is taking a grating monochromator. In the present paper the detection principle and the structure of the echelle grating monochromator are described, the high order and lower order quantum number of the probe spectrum is resolved. The focal length of the collimating-focusing optical system is calculated by analyzing echelle grating's spectroscopic principle and dispersion ability. Subsequently spectral effect is simulated with Zemax software. The simulation result indicates that under the condition of the probe laser wavelength of 532 nm and using echelle grating monochromator, Rarnan spectrums of 529.05, 530.40, 533.77, 535.13 mn can be separated well, at the same time, the SNR of the system is enhanced by summing the spectral signals of symmetric quantum number. The echelle grating monochromator is small in size, and can easily meet the requirements of the miniaturization of Raman Lidar temperature measurement system. PMID:23697156

Ge, Xian-Ying; Chen, Si-Ying; Zhang, Yin-Chao; Chen, He; Guo, Pan; Bu, Zhi-Chao; Chen, Sheng-Zhe

2013-02-01

12

CHIRON -A Fiber-fed High-resolution Echelle Spectrometer At CTIO 1.5m Telescope  

E-print Network

CHIRON - A Fiber-fed High-resolution Echelle Spectrometer At CTIO 1.5m Telescope J.F.P. Spronck (1 is a highly stable cross-dispersed echelle spectrometer deployed at CTIO 1.5m telescope. It is fed by fiber-micron fiber (2.7" on sky) ·Image Slicer (3 slices) ·140-mm beam ·R2 grating ·Cross-disperser prism

Tokovinin, Andrei A.

13

Echelle crossed grating millimeter wave beam scanner.  

PubMed

We present a two-dimensional, active, millimeter-wave, electronic beam scanner, with Doppler capabilities for stand-off imaging. The two-dimensional scan is achieved by mapping the millimeter wave spectrum to space using a pair of crossed gratings. The active transceiver and heterodyne quadrature detection allow the measurement of the relative phase between two consecutive measurements and the synthesis of the scene's Doppler signature. The frame rate of the imager is currently limited by the sweep rate of the vector network analyzer which is used to drive the millimeter wave extenders. All of the beam steering components are passive and can be designed to operate at any wavelength. The system design, characterization and measurements are presented and further uses and improvements are suggested. PMID:24977888

Furxhi, Orges; Marks, Daniel L; Brady, David J

2014-06-30

14

The Cryogenic Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The Cryogenic Grating Spectrometer (CGS) first flew on the KAO in 1982 December and has been open to guest investigators since 1984 October. In the past 12 years it has completed over 100 research flights supporting 13 different principal investigators studying a variety of objects. We briefly describe the instrument, its capabilities and accomplishments, and acknowledge the people who have contributed to its development and operation.

Erickson, Edwin F.; Haas, Michael R.; Colgan, Sean W. J.; Simpson, Janet P.; Rubin, Robert H.

1995-01-01

15

Diffraction Effects in a Grating Spectrometer  

NASA Technical Reports Server (NTRS)

This paper describes a numerical study of diffraction effects in the AIRES optical system using GLAD by Applied Optics Research. AIRES (or Airborne Infrared Echelle Spectrometer) employs two gratings in series. The small, first-order (i.e., predisperser) grating sorts orders for the large, high-order echelle grating, thus providing moderately high spectral resolution over 3.6 octaves in wavelength. The AIRES' optical design includes three field stops (i.e., a circular aperture and two long, narrow slits) and four pupil stops. A detailed diffraction analysis is required to evaluate critical trade-offs between spectral resolution, optical throughput, detector background, scattered light, and system size and weight. Such an analysis must consider diffraction effects at the pupil stops (edge diffraction), at the field stops (spatial filtering), and at intermediate positions where other optical elements are located. The effects of slit width, slit length, oversizing of the second slit relative to the first, baffling at the Lyot stop and subsequent pupil stops, and the necessity for oversizing other optical elements are presented and discussed. It is found that for narrow slits, the downstream energy distribution is significantly broadened relative to that for large slits, where telescope diffraction dominates, leading to significantly more light loss than anticipated, unless other key optical elements are oversized. The importance of performing a proper diffraction analysis is emphasized and the suitability of GLAD for this task is discussed.

Haas, Michael R.; DeVincenzi, D. (Technical Monitor)

2002-01-01

16

First: Florida Ir Silicon Immersion Grating Spectrometer  

NASA Astrophysics Data System (ADS)

The FIRST silicon immersion grating spectrometer is being developed at UF to search for habitable Earth-like planets around M dwarfs and giant planets around young active stars. This compact cryogenic IR instrument is designed to have a spectral resolution of R=72,000 at 1.4-1.8 m with a silicon immersion grating and R=60K at 0.8-1.35 m with an R4 echelle. The goal is to reach a long term Doppler precision of 1-3 m/s for bright M dwarfs. The FIRST silicon immersion grating, with 54.74 degree blaze angle and 16 l/mm groove density, has been fully characterized in the lab. The 50x50 mm square grating entrance pupil is coated with a single layer of anti-reflection coating resulting in a 2.1% measured reflection loss. The grating surface was coated with a gold layer to increase grating surface reflectivity. It has produced R=110,000 diffraction limited spectral resolution at 1.523 micron in a lab test spectrograph with 20 mm pupil diameter. The integrated scattered light is less than 0.2\\% and grating has no visible ghosts down to the measuring instrument noise level. The grating efficiency is 69\\% at the peak of the blaze. This silicon immersion grating is ready for scientific observations with FIRST. FIRST is scheduled to be integrated in the lab during the spring of 2012 and see the first light at an astronomical telescope (TBD) the summer of 2012.

Ge, Jian; Zhao, B.; Wang, J.; Wan, X.; Powell, S.

2012-01-01

17

Exploiting a transmission grating spectrometer  

SciTech Connect

The availability of compact transmission grating spectrometers now allows an attractive and economical alternative to the more familiar Czerny-Turner configuration for many high-temperature plasma applications. Higher throughput is obtained with short focal length refractive optics and stigmatic imaging. Many more spectra can be obtained with a single spectrometer since smaller, more densely packed optical input fibers can be used. Multiple input slits, along with a bandpass filter, can be used to maximize the number of spectra per detector, providing further economy. Curved slits can correct for the strong image curvature of the short focal length optics. Presented here are the governing grating equations for both standard and high-dispersion transmission gratings, defining dispersion, image curvature, and desired slit curvature, that can be used in the design of improved plasma diagnostics.

Bell, Ronald E. [Princeton Plasma Physics Laboratory, Princeton University, Princeton New Jersey 08543-0451 (United States)

2004-10-01

18

Exploiting a Transmission Grating Spectrometer  

SciTech Connect

The availability of compact transmission grating spectrometers now allows an attractive and economical alternative to the more familiar Czerny-Turner configuration for many high-temperature plasma applications. Higher throughput is obtained with short focal length refractive optics and stigmatic imaging. Many more spectra can be obtained with a single spectrometer since smaller, more densely packed optical input fibers can be used. Multiple input slits, along with a bandpass filter, can be used to maximize the number of spectra per detector, providing further economy. Curved slits can correct for the strong image curvature of the short focal length optics. Presented here are the governing grating equations for both standard and high-dispersion transmission gratings, defining dispersion, image curvature, and desired slit curvature, that can be used in the design of improved plasma diagnostics.

Ronald E. Bell

2004-12-08

19

Chiron - A Fiber-fed High-resolution Echelle Spectrometer At Ctio 1.5m Telescope  

NASA Astrophysics Data System (ADS)

Small telescopes can play an important role in the search for exoplanets because they offer an opportunity for high cadence observations that are not possible with large aperture telescopes. CHIRON is a highly stable cross-dispersed echelle spectrometer deployed at CTIO 1.5m telescope. It is fed by fiber and intended primarily for precise radial velocities. It is currently mainly used to search for low mass planets around alpha Centauri A and B. An iodine cell is used for wavelength calibration. The optical layout is a classical echelle with 150 mm collimator size. The bench-mounted spectrometer is fiber-fed followed by an image slicer or a slit mask. For the grating, we used the existing R2 echelle grating (that has a throughput of about 50%). An apochromatic refractor is used as the camera. Image quality of the design is excellent over the full spectral range. The instrument has been commissioned in March 2011. It has four observing modes: (a) unsliced fiber (R = 25,000-30,000), (b) image slicer (3 slices, R=80,000), (c) wide slit (R = 80,000-90,000) and (d) narrow slit (R = 120,000). The spectral format spans 4200 to 8700 Angstroms. The total throughput of the telescope and spectrometer is 5-6%. Replacement of the grating and coating of the prism will further improve the efficiency. Furthermore, the spectrometer is in a closed temperature-stabilized environment and pressure stabilization is currently being implemented. An exposure meter to precisely calculate the photon-weighted mid-point time will be installed in June 2011.

Spronck, Julien; Schwab, C.; Tokovinin, A.; Giguere, M.; Szymkowiak, A.; Fischer, D.

2011-05-01

20

JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 31, NO. 13, JULY 1, 2013 2099 Echelle Diffractive Grating Based Wavelength  

E-print Network

. Index Terms--Echelle diffractive grating, fiber Bragg grating (FBG), fiber optic sensors, interrogator (SHM). Fiber Bragg grating (FBG) sensors have demonstrated great potential in both. But the currently, and piezoelectric (PZT) based acoustic sensors are the most studied techniques for impact damage detection. However

Yao, Jianping

21

Imaging spectrometer/camera having convex grating  

NASA Technical Reports Server (NTRS)

An imaging spectrometer has fore-optics coupled to a spectral resolving system with an entrance slit extending in a first direction at an imaging location of the fore-optics for receiving the image, a convex diffraction grating for separating the image into a plurality of spectra of predetermined wavelength ranges; a spectrometer array for detecting the spectra; and at least one concave sperical mirror concentric with the diffraction grating for relaying the image from the entrance slit to the diffraction grating and from the diffraction grating to the spectrometer array. In one embodiment, the spectrometer is configured in a lateral mode in which the entrance slit and the spectrometer array are displaced laterally on opposite sides of the diffraction grating in a second direction substantially perpendicular to the first direction. In another embodiment, the spectrometer is combined with a polychromatic imaging camera array disposed adjacent said entrance slit for recording said image.

Reininger, Francis M. (Inventor)

2000-01-01

22

Convex Diffraction Grating Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

A 1:1 Offner mirror system for imaging off-axis objects is modified by replacing a concave spherical primary mirror that is concentric with a convex secondary mirror with two concave spherical mirrors M1 and M2 of the same or different radii positioned with their respective distances d1 and d2 from a concentric convex spherical diffraction grating having its grooves parallel to the entrance slit of the spectrometer which replaces the convex secondary mirror. By adjusting their distances d1 and d2 and their respective angles of reflection alpha and beta, defined as the respective angles between their incident and reflected rays, all aberrations are corrected without the need to increase the spectrometer size for a given entrance slit size to reduce astigmatism, thus allowing the imaging spectrometer volume to be less for a given application than would be possible with conventional imaging spectrometers and still give excellent spatial and spectral imaging of the slit image spectra over the focal plane.

Chrisp, Michael P. (Inventor)

1999-01-01

23

An FIR cooled grating spectrometer for the Kuiper Airborne Observatory  

NASA Technical Reports Server (NTRS)

The design and performance of a liquid-He-cooled spectrometer being developed for the Kuiper Airborne Observatory (KAO) to study FIR lines originating in the interstellar medium are discussed. Currently, the spectrometer contains six Ge:Ga photoconductor detectors mounted in integrating cavities and cooled to about 3 K; the collimator focal plane has space for 39 such detectors. The instrument achieves a maximum resolving power of 6000 by means of a 45-cm long echelle grating and is optically capable of operating in the spectral range 25-300 microns. A laboratory spectrum of water vapor, an atmospheric water absorption feature measured from the KAO with Mars as a source, and the forbidden O(2+) emission from W51-IRS1 are shown.

Erickson, E. F.; Haas, M. R.; Hollenbach, D. J.; Simpson, J. P.; Augason, G. C.; Houck, J. R.; Harwit, M. O.; Rank, D. M.

1985-01-01

24

The Constellation-X reflection grating spectrometer  

Microsoft Academic Search

The Constellation-X Reflection Grating Spectrometer (RGS) is designed to provide high-throughput, high-resolution spectra in the long wavelength band of 6 to 50 angstrom. In the nominal design an array of reflection gratings is mounted at the exit of the Spectroscopy X-ray Telescope (SXT) mirror module. The gratings intercept and disperse light to a designated array of CCD detectors. To achieve

Jean Cottam; Webster Cash; Kathryn A. Flanagan; Ralf K. Heilmann; Gregory Y. Prigozhin; Andrew P. Rasmussen; George R. Ricker; Mark L. Schattenburg; Eric Schindhelm

2006-01-01

25

On the multiple grating spectrometer resolving power  

Microsoft Academic Search

The resolution for multiple grating spectrometers is obtained using the transfer function formalism. It is shown that the limiting resolving power for a system of n equal gratings in additive dispersion lambda\\/Delta lambda sub g (n) is overestimated by previous calculations even for low n values. It is also found that when n is increased this quantity reaches a limiting

V. Mazzacurati; G. Ruocco; G. Signorelli

1988-01-01

26

Micro Ring Grating Spectrometer with Adjustable Aperture  

NASA Technical Reports Server (NTRS)

A spectrometer includes a micro-ring grating device having coaxially-aligned ring gratings for diffracting incident light onto a target focal point, a detection device for detecting light intensity, one or more actuators, and an adjustable aperture device defining a circular aperture. The aperture circumscribes a target focal point, and directs a light to the detection device. The aperture device is selectively adjustable using the actuators to select a portion of a frequency band for transmission to the detection device. A method of detecting intensity of a selected band of incident light includes directing incident light onto coaxially-aligned ring gratings of a micro-ring grating device, and diffracting the selected band onto a target focal point using the ring gratings. The method includes using an actuator to adjust an aperture device and pass a selected portion of the frequency band to a detection device for measuring the intensity of the selected portion.

Park, Yeonjoon (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor); Choi, Sang H. (Inventor)

2012-01-01

27

MISE: A multiwavelength imaging spectrograph using echelle grating for daytime optical aeronomy investigations  

NASA Astrophysics Data System (ADS)

A high-spectral resolution multiwavelength imaging slit spectrograph using echelle grating (MISE) that is capable of measuring daytime optical emissions at multiple wavelengths simultaneously over a large (140) field-of-view is presented. Optical emissions during daytime (either dayglow or daytime aurora) are buried in the strong daytime solar scattered background continuum and therefore very high spectral resolution measurements are required to obtain their contributions. MISE measures the emission intensities of OI 557.7nm, OI 630.0nm, and OI 777.4nm that originate in the upper atmosphere. The dispersion achieved by the spectrograph at these three spectral regions, respectively, is 0.004, 0.0049, and 0.0059nmpixel-1. By using an echelle grating as the dispersing element, multiple spectral regions of aeronomic interest are made to fall in the same diffraction angle range so that rotation of grating is avoided. This instrument is immune to ambient temperature fluctuations and vibrations and is suitable for long and continuous field operations. The spectral and intensity calibration of this instrument along with the data analysis methodology are discussed. Sample data of emission intensities from all the three wavelengths mentioned above for a couple of days obtained from Hyderabad (17N, 80E; 8.7N Mag. Lat.) are presented which show a good similarity when compared with those of empirical and photochemical model results. The OI 557.7nm daytime emissions are measured sparsely from ground-based techniques and ground-based OI 777.4nm daytime emissions from ground are presented for the first time, to the best of our knowledge. The variability is highlighted and the potential of such measurements to derive information on vertical coupling of atmospheric regions and wave dynamics during daytime are discussed.

Pallamraju, Duggirala; Laskar, Fazlul I.; Singh, Ravindra P.; Baumgardner, Jeffrey; Chakrabarti, Supriya

2013-10-01

28

Beam Shape Effects on Grating Spectrometer Resolution  

NASA Technical Reports Server (NTRS)

The collimated optical beam in a grating spectrometer may be circular or elliptical in cross section, so that different parts of the beam illuminate different numbers of grooves on the grating. Here we estimate the consequent loss in spectral resolution relative to that obtained with a beam which illuminates a fixed number of grooves. For representative diffraction resolution functions, the effect is to reduce the intrinsic resolving power of the spectrometer by about 13%, exclusive of other contributions such as finite entrance slit width.

Erickson, Edwin F.; Rabanus, David; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

29

New Convex Grating Types for Concentric Imaging Spectrometers  

NASA Technical Reports Server (NTRS)

The properties of convex gratings fabricated by electron-beam lithography are investigated. Three grating types are shown. These gratings allow the optical designer to fully realize the considerable advantages of concentric spectrometer forms.

Mouroulis, P.; Wilson, D. W.; Maker, P. D.; Maker, R. E.; Muller, R. E.

1998-01-01

30

Electro-optic phase grating streak spectrometer  

NASA Astrophysics Data System (ADS)

The Electro-optic phase grating streak spectrometer (EOPGSS) generates a time-resolved spectra equivalent to that obtained with a conventional spectrometer/streak camera combination, but without using a streak camera (by far the more expensive and problematic component of the conventional system). The EOPGSS is based on a phase, rather than an amplitude grating. Further, this grating is fabricated of electro-optic material such as, for example, KD*P, by either etching grooves into an E-O slab, or by depositing lines of the E-O material onto an optical flat. An electric field normal to the grating alters the material's index of refraction and thus affects a shift (in angle) of the output spectrum. Ramping the voltage streaks the spectrum correspondingly. The streak and dispersion directions are the same, so a second (static, conventional) grating disperses the spectrum in the orthogonal direction to prevent different wavelengths from ``overwriting'' each other. Since the streaking is done by the grating, the streaked output spectrum is recorded with a time-integrating device, such as a CCD. System model, typical design, and performance expectations will be presented.

Goldin, Fletcher

2012-10-01

31

The Constellation-X reflection grating spectrometer Jean Cottama  

E-print Network

The Constellation-X reflection grating spectrometer Jean Cottama , Webster Cashb , Kathryn A University, SLAC, Menlo Park, CA USA 94025 ABSTRACT The Constellation-X Reflection Grating Spectrometer (RGS. Keywords: X-ray, spectrometer, grating, CCD, Constellation-X 1. INTRODUCTION Constellation-X1 is one

32

Inflight calibration of the XMMNewton Reflection Grating Spectrometers  

E-print Network

In­flight calibration of the XMM­Newton Reflection Grating Spectrometers C. Erd a , M. Audard b , A The Reflection Grating Spectrometer (RGS) 1--3 on European Space Agency's (ESA) X­ray observatory XMM­ Newton 4 is a dispersive spectrometer which, for the first time in X­ray astronomy, uses reflection gratings as dispersive

Audard, Marc

33

Imaging Spectrometers Using Concave Holographic Gratings  

NASA Technical Reports Server (NTRS)

Imaging spectroscopy combines the spatial attributes of imaging with the compositionally diagnostic attributes of spectroscopy. For spacebased remote sensing applications, mass, size, power, data rate, and application constrain the scanning approach. For the first three approaches, substantial savings in mass and size of the spectrometer can be achieved in some cases with a concave holographic grating and careful placement of an order-sorting filter. A hologram etched on the single concave surface contains the equivalent of the collimating, dispersing, and camera optics of a conventional grating spectrometer and provides substantial wavelength dependent corrections for spherical aberrations and a flat focal field. These gratings can be blazed to improve efficiency when used over a small wavelength range or left unblazed for broadband uniform efficiency when used over a wavelength range of up to 2 orders. More than 1 order can be imaged along the dispersion axis by placing an appropriately designed step order-sorting filter in front of the one- or two-dimensional detector. This filter can be shaped for additional aberration corrections. The VIRIS imaging spectrometer based on the broadband design provides simultaneous imaging of the entrance slit from lambda = 0.9 to 2.6 microns (1.5 orders) onto a 128 x 128 HgCdTe detector (at 77 K). The VIRIS spectrometer was used for lunar mapping with the UH 24.in telescope at Mauna Kea Observatory. The design is adaptable for small, low mass, space based imaging spectrometers.

Gradie, J.; Wang, S.

1993-01-01

34

A set of innovative immersed grating based spectrometer designs for METIS  

NASA Astrophysics Data System (ADS)

We present innovative, immersed grating based optical designs for the SMO (Spectrograph Main Optics) module of the Mid-infrared E-ELT Imager and Spectrograph, METIS. The immersed grating allows a significant reduction of SMO volume compared to conventional echelle grating designs, because the diffraction takes place in high refractive index silicon. Additionally, using novel optimization techniques and technical solutions in silicon micromachining offered by the semiconductor industry, further improvements can be achieved. We show optical architectures based on compact, double-pass Three Mirror Anastigmat (TMA) designs, which appear advantageous in terms of one or several of the following: optical performance, reduction of volume, ease of manufacturing and testing. We explore optical designs, where the emphasis is put on manufacturability and we investigate optical solutions, where the ultimate goal is the highest possible optical performance. These novel, silicon immersed grating based design concepts are applicable for future earth and space based spectrometers.

Agcs, Tibor; Navarro, Ramon; Venema, Lars; van Amerongen, Aaldert H.; Tol, Paul J. J.; van Brug, Hedser; Brandl, Bernhard R.; Molster, Frank; Todd, Stephen

2014-07-01

35

Development of infrared Echelle spectrograph and mid-infrared heterodyne spectrometer on a small telescope at Haleakala, Hawaii for planetary observation  

NASA Astrophysics Data System (ADS)

We report the development of infrared Echelle spectrograph covering 1 - 4 micron and mid-infrared heterodyne spectrometer around 10 micron installed on the 60-cm telescope at the summit of Haleakala, Hawaii (alt.=3000m). It is essential to carry out continuous measurement of planetary atmosphere, such as the Jovian infrared aurora and the volcanoes on Jovian satellite Io, to understand its time and spatial variations. A compact and easy-to-use high resolution infrared spectrometer provide the good opportunity to investigate these objects continuously. We are developing an Echelle spectrograph called ESPRIT: Echelle Spectrograph for Planetary Research In Tohoku university. The main target of ESPRIT is to measure the Jovian H3+ fundamental line at 3.9 micron, and H2 nu=1 at 2.1 micron. The 256x256 pixel CRC463 InSb array is used. An appropriate Echelle grating is selected to optimize at 3.9 micron and 2.1 micron for the Jovian infrared auroral observations. The pixel scale corresponds to the atmospheric seeing (0.3 arcsec/pixel). This spectrograph is characterized by a long slit field-of-view of ~ 50 arcsec with a spectral resolution is over 20,000. In addition, we recently developed a heterodyne spectrometer called MILAHI on the 60 cm telescope. MILAHI is characterized by super high-resolving power (more than 1,500,000) covering from 7 - 13 microns. Its sensitivity is 2400 K at 9.6 micron with a MCT photo diode detector of which bandwidth of 3000 MHz. ESPRIT and MILAHI is planned to be installed on 60 cm telescope is planned in 2014.

Sakanoi, Takeshi; Kasaba, Yasumasa; Kagitani, Masato; Nakagawa, Hiromu; Kuhn, Jeff; Okano, Shoichi

2014-08-01

36

Upgraded control, acquisition program and user interface for the Manchester Echelle Spectrometer at San Pedro Martir  

NASA Astrophysics Data System (ADS)

We describe the recent upgrade of the Manchester Echelle Spectrometer, currently in use at San Pedro Mrtir. This upgrade has included a user interface and a new CCD acquisition software. The spectrometer control is now done by a microcontroller, whose inputs are new sensors and encoders installed inside the spectrometer. The instrument control is now fully carried out from a graphical user interface running in a personal computer. The acquisition computer sends the images to the GUI through an ethernet link. In this paper, we present the general scheme and the programs developed for Linux (in C++ and Tcl/Tk) that permits an easy integral operation of the instrument, as well as the creation of scripts intended to the optimization of the observing run and the future interaction with the telescope and the guider. This upgraded system has been operated successfully during several campaigns in the 2.1-meter telescope at Observatorio Astronmico Nacional in San Pedro Mrtir.

Gutirrez, Leonel; Murillo, J.; Quiroz, Fernando; Pedrayes, Maria H.; Meaburn, John; Lpez, Jose A.

2002-12-01

37

The Constellation-X Reflection Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The Reflection Grating Spectrometer on the Constellation-X mission will provide high sensitivity, high-resolution spectra in the soft x-ray band. The RGS performance requirements are specified as a resolving power of greater than 300 and an effective area of greater than 1000 sq cm across most of the 0.25 to 2.0 keV band. These requirements are driven by the science goals of the mission. We will describe the performance requirements and goals, the reference design of the spectrometer, and examples of science cases where we expect data from the RGS to significantly advance our current understanding of the universe.

Allen, Jean C.

2006-01-01

38

Calibration and efficiency of the Einstein objective grating spectrometer  

Microsoft Academic Search

The Einstein Observatory, a large satellite dedicated to X-ray astronomy, carried the first large X-ray telescope to be placed in orbit and an objective grating spectrometer with two sets of gratings. This paper lists prelaunch calibration results and describes the derivation of spectrometer efficiency and resolution. Several calibration spectra are shown, and theoretical grating parameters are derived from the calibration

F. D. Seward; T. Chlebowski; J. P. Delvaille; J. P. Henry; S. M. Kahn; L. van Speybroeck; J. Dijkstra; A. C. Brinkman; J. Heise; R. Mewe; J. Schrijver

1982-01-01

39

Lower order blaze grating spectrometer of large diffraction angle  

Microsoft Academic Search

A new kind of large dispersion lower order blaze grating spectrometer is built. The design is based on the use of uncustomary large angles of incidence and diffraction approaching 80. The double diffraction optical scheme is employed to fit the design conception. A set of compact size grating spectrometers of various focal lengths and grating ruled widths has been manufactured

Yu. S. Koshkin; E. E. Mukhin; G. T. Razdobarin; V. V. Semenov; A. N. Shilnikov; Yu. K. Mihailovskij; L. I. Bakh

1999-01-01

40

Single-detector micro-electro-mechanical scanning grating spectrometer  

Microsoft Academic Search

A compact, robust grating spectrometer based on an optimised micro-electro-mechanical grating mirror component has been developed,\\u000a built, and characterised. The application of an oscillating reflection grating micro-mirror component as scanning dispersive\\u000a element in a modified CzernyTurner monochromator layout enables the design of compact grating spectrometers capable of acquiring\\u000a full spectra using a single detector element. Designed for a wavelength range

M. Kraft; A. Kenda; A. Frank; W. Scherf; A. Heberer; T. Sandner; H. Schenk; F. Zimmer

2006-01-01

41

UNIVERSIT AT OSNABR UCK 1 Grating Spectrometer GRATING.TEX KB 20020119  

E-print Network

UNIVERSIT ¨AT ?OSNABR ¨UCK 1 Grating Spectrometer GRATING.TEX KB 20020119 KLAUS BETZLER1-known properties of spectrometers. As an addition to textbooks, it may present some help to students working over the field of spectroscopy. 1 Grating Mathematics 1.1 Transfer Function As a general rule

Osnabrück, Universität

42

Transmission Grating Spectrometers in Undergraduate Astronomy Laboratories  

NASA Astrophysics Data System (ADS)

The Iowa Robotic Telescope, located in southern Arizona, has been used in University of Iowa undergraduate laboratories for more than a decade. The addition of a low-resolution transmission grating spectrometer (TGS) to the 0.37 m classical Cassegrain reflector has allowed students to obtain spectra of stars, planets, and nebulae as regular part of the lab curriculum. We discuss the relative efficiency and resolution dependences using different groove spacings, slits, telescope optics, and camera sensor geometries. In addition, we consider the use of beam steering prisms joined with diffraction gratings (grisms). Students may schedule the TGS system using a simple web-based form to observe targets down to approximately 10th magnitude. Some of the TGS observational targets include Wolf-Rayet stars with optically thick winds, novae, as well as main sequence stars over the entire spectral sequence.

Hood, Ryan; Moore, J.; McKinlay, M.; Coffin, D.; Trieweiler, D.; Mutel, R. L.

2012-01-01

43

Cooled grating infrared spectrometer for astronomical observations  

NASA Technical Reports Server (NTRS)

A liquid helium-cooled infrared spectrometer for the 16 to 50 micron range is described. The instrument has six detectors, three each of Si:Sb and Ge:Ga and two diffraction gratings mounted back-to-back. Cold preoptics are used to match the spectrometer to the telescope. In its nominal configuration the system resolution is 0.03 micron from 16 to 30 microns and 0.07 micron from 28 to 50 microns. A cooled filter wheel is used to change order sorting filters. The gratings are driven by a steel band and gear train operating at 4 K. The detector outputs are amplified by a TIA, employing a matched pair of JFETs operating at 70 K inside the dewar. The external warm electronics include a gain stage for the TIA and dc-coupled gating circuit to remove charged-particle (cosmic-ray secondary)-induced noise spikes. The gating circuit reduces the overall system noise by a factor of two when the spectrometer is used on NASA's Kuiper Airborne Observatory. Sample spectra are presented and the deglitcher performance is illustrated.

Houck, J. R.; Gull, G. E.

1983-01-01

44

Immersion echelle spectrograph  

DOEpatents

A small spectrograph containing no moving components and capable of providing high resolution spectra of the mid-infrared region from 2 microns to 4 microns in wavelength. The resolving power of the spectrograph exceeds 20,000 throughout this region and at an optical throughput of about 10.sup.-5 cm.sup.2 sr. The spectrograph incorporates a silicon immersion echelle grating operating in high spectral order combined with a first order transmission grating in a cross-dispersing configuration to provide a two-dimensional (2-D) spectral format that is focused onto a two-dimensional infrared detector array. The spectrometer incorporates a common collimating and condensing lens assembly in a near aberration-free axially symmetric design. The spectrometer has wide use potential in addition to general research, such as monitoring atmospheric constituents for air quality, climate change, global warming, as well as monitoring exhaust fumes for smog sources or exhaust plumes for evidence of illicit drug manufacture.

Stevens, Charles G. (Danville, CA); Thomas, Norman L. (Livermore, CA)

2000-01-01

45

Faceted grating prism for a computed tomographic imaging spectrometer  

E-print Network

Faceted grating prism for a computed tomographic imaging spectrometer Michael W. Kudenov Julia://opticalengineering.spiedigitallibrary.org/ on 02/04/2013 Terms of Use: http://spiedl.org/terms #12;Faceted grating prism for a computed tomographic imaging spectrometer Michael W. Kudenov Julia Craven-Jones The University of Arizona College of Optical

Dereniak, Eustace L.

46

Hyphenation of a near-infrared Echelle spectrometer to a microplasma for element-selective detection in gas chromatography.  

PubMed

The coupling of a near-infrared Echelle spectrometer (NIRES) with a gas chromatograph for element-selective detection is introduced. The miniaturized capacitive plasma device is operated at a frequency of 40.68 MHz and is mounted directly on an Hewlett-Packard HP6890 GC. First results with a mixture of halogenated standard compounds are presented and discussed in terms of the advantages and problems with this system. PMID:11798094

Cziesla, K; Platzer, B; Okruss, M; Florek, S; Otto, M

2001-12-01

47

Compact echelle spectrometer for occultation sounding of the Martian atmosphere: design and performance.  

PubMed

The echelle spectrometer TIMM-2 is the instrument developed for the unsuccessful Russian mission Phobos-Grunt. The instrument was dedicated to solar occultation studies of the Martian atmosphere by measuring the amount of methane, by sensitive measuring of other minor constituents, and by profiling the D/H ratio and the aerosol structure. The spectral range of the instrument is 2300-4100 nm, the spectral resolving power ?/?? exceeds 25,000, and the field of view is 1.521 arc min. The spectra are measured in narrow spectral intervals, corresponding to discreet diffraction orders. One measurement cycle includes several spectral intervals. To study the vertical profiles of aerosol, the instrument incorporates four photometers in the UV to near-IR spectral range. The mass of the instrument is 2800 g, and its power consumption is 12 W. One complete flight model remains available after the Phobos-Grunt launch. We discuss the science objectives of the occultation experiment for the case of Mars, the implementation of the instrument, and the results of ground calibrations. PMID:23400068

Korablev, Oleg; Montmessin, Franck; Trokhimovsky, Alexander; Fedorova, Anna A; Kiselev, Alexander V; Bertaux, Jean-Loup; Goultail, Jean-Pierre; Belyaev, Denis A; Stepanov, Alexander V; Titov, Andrei Yu; Kalinnikov, Yurii K

2013-02-10

48

Numerical optimization of spherical VLS grating X-ray spectrometers  

E-print Network

Operation of an X-ray spectrometer based on a spherical variable line spacing grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and spectrometer geometry. The analysis is illustrated with optical design of a model spectrometer to deliver a resolving power above 20400 at photon energy of 930 eV (Cu L-edge). With this energy taken as reference, the VLS coefficients are optimized to cancel the lineshape asymmetry (mostly from the coma aberrations) as well as minimize the symmetric aberration broadening at large grating illuminations, dramatically increasing the aberration-limited vertical acceptance of the spectrometer. For any energy away from the reference, we evaluate corrections to the entrance arm and light incidence angle on the grating to maintain the exactly symmetric lineshape. Furthermore, we evaluate operational modes when these corrections are coordinated to maintain either energy independent focal curve inclination or maximal aberration-lim...

Strocov, V N; Flechsig, U; Patthey, L; Chiuzb?ian, G S

2010-01-01

49

Spectral calibration for convex grating imaging spectrometer  

NASA Astrophysics Data System (ADS)

Spectral calibration of imaging spectrometer plays an important role for acquiring target accurate spectrum. There are two spectral calibration types in essence, the wavelength scanning and characteristic line sampling. Only the calibrated pixel is used for the wavelength scanning methods and he spectral response function (SRF) is constructed by the calibrated pixel itself. The different wavelength can be generated by the monochromator. The SRF is constructed by adjacent pixels of the calibrated one for the characteristic line sampling methods. And the pixels are illuminated by the narrow spectrum line and the center wavelength of the spectral line is exactly known. The calibration result comes from scanning method is precise, but it takes much time and data to deal with. The wavelength scanning method cannot be used in field or space environment. The characteristic line sampling method is simple, but the calibration precision is not easy to confirm. The standard spectroscopic lamp is used to calibrate our manufactured convex grating imaging spectrometer which has Offner concentric structure and can supply high resolution and uniform spectral signal. Gaussian fitting algorithm is used to determine the center position and the Full-Width-Half-Maximum?FWHM?of the characteristic spectrum line. The central wavelengths and FWHMs of spectral pixels are calibrated by cubic polynomial fitting. By setting a fitting error thresh hold and abandoning the maximum deviation point, an optimization calculation is achieved. The integrated calibration experiment equipment for spectral calibration is developed to enhance calibration efficiency. The spectral calibration result comes from spectral lamp method are verified by monochromator wavelength scanning calibration technique. The result shows that spectral calibration uncertainty of FWHM and center wavelength are both less than 0.08nm, or 5.2% of spectral FWHM.

Zhou, Jiankang; Chen, Xinhua; Ji, Yiqun; Chen, Yuheng; Shen, Weimin

2013-12-01

50

Accurate wavelength calibration method for flat-field grating spectrometers.  

PubMed

A portable spectrometer prototype is built to study wavelength calibration for flat-field grating spectrometers. An accurate calibration method called parameter fitting is presented. Both optical and structural parameters of the spectrometer are included in the wavelength calibration model, which accurately describes the relationship between wavelength and pixel position. Along with higher calibration accuracy, the proposed calibration method can provide information about errors in the installation of the optical components, which will be helpful for spectrometer alignment. PMID:21929865

Du, Xuewei; Li, Chaoyang; Xu, Zhe; Wang, Qiuping

2011-09-01

51

Liquid helium cooled balloon-borne grating spectrometer system  

Microsoft Academic Search

A Littrow grating spectrometer designed to operate in a liquid helium dewar at a temperature of 4K was constructed as the major effort in this program. The problems associated with construction of such an instrument and the methods used to solve them are discussed. The spectrometer was designed to be used on a balloon-borne platform and to measure the atmospheric

W. J. Williams; J. J. Kosters; J. N. Brooks; D. G. Murcray

1974-01-01

52

Variable line-space gratings - New designs for use in grazing incidence spectrometers  

NASA Technical Reports Server (NTRS)

An account is given of a fundamentally different approach to the use of variable line-space gratings for grazing incidence spectrometers. In the new approach, the gratings are flat and they are placed to intercept the converging beam from a collecting mirror rather than the diverging beam from a slit. This results in (1) small aberrations over a wide instantaneous range in wavelength, (2) a modest required variation in line spacing across the ruled width, (3) a simultaneous minimization of both the spectral and image height aberrations, and (4) a completely stigmatic zero order image. The slitless arrangement common to these designs is very compact, having no additional length behind the focal plane of the collecting mirror. In-plane and conical fan designs are considered. One combination design, in the form of an echelle spectrometer, is discussed. The designs are considered to represent ideal candidates for moderate to high resolution spectrometers on such missions as the Far Ultraviolet Spectroscopic Explorer (FUSE, now Columbus) and the Advanced X-ray Astrophysics Facility (AXAF).

Hettrick, M. C.; Bowyer, S.

1983-01-01

53

A New Large Echelle Spectrometer for Measuring Atomic Transition Probabilities of Fe-group Ions  

NASA Astrophysics Data System (ADS)

Accurate atomic transition probabilities for weak lines connected to the ground and low metastable levels of Fe-group ions are needed for elemental abundance studies on metal-poor stars. Metal-poor stars represent the oldest observable stellar generation and offer a direct probe into the early history of nucleosynthesis and the chemical evolution of the Galaxy. Unexplained trends in relative Fe-group abundances, such as [Co/Cr], as a function of metallicity, or [Fe/H], have been observed. These trends may result from a breakdown in the local thermodynamic equilibrium (LTE) approximation used in traditional photosphere models underlying elemental abundance determinations. The ground and low metastable levels of Fe-group ions contain most of the Fe-group material in a stellar photosphere, and thus second spectra lines with low E.P.s are essentially immune to non-LTE effects. To improve lab data on important Fe-group lines we have developed a novel instrument based on a 3 meter focal length vacuum echelle spectrograph combined with an aberration corrected cross dispersion system and a UV sensitive CCD array. This spectrometer is capable of recording both emission and absorption spectra with high resolving power, very broad wavelength coverage, and high signal-to-noise. It is also free from the multiplex noise of a FTS, making it ideally suited for measuring branching fractions of very weak lines. The combination of very accurate branching fractions with radiative lifetimes from time-resolved laser-induced fluorescence will yield accurate absolute transition probabilities of weak second spectra lines with low E.P.s for the Fe-group elements. Instrument design and preliminary results will be presented. Supported by NASA Grant NNX09AL13G.

Wood, Michael; Lawler, J. E.

2012-01-01

54

On-sky performance of a high resolution silicon immersion grating spectrometer  

NASA Astrophysics Data System (ADS)

High resolution infrared spectroscopy has been a major challenging task to accomplish in astronomy due to the enormous size and cost of IR spectrographs built with traditional gratings. A silicon immersion grating, due to its over three times high dispersion over a traditional reflective grating, offers a compact and low cost design of new generation IR high resolution spectrographs. Here we report the on-sky performance of the first silicon immersion grating spectrometer, called Florida IR Silicon immersion grating spectromeTer (FIRST), commissioned at the 2-meter Automatic Spectroscopic Telescope (AST) of Fairborn Observatory in Arizona in October 2013. The measured spectral resolution is R=50,000 with a 50 mm diameter spectrograph pupil and a blaze angle of 54.7 degree. The 1.4-1.8 ?m wavelength region (the Red channel) is completely covered in a single exposure with a 2kx2k H2RG IR array while the 0.8-1.35 ?m region is nearly completely covered by the cross-dispersed echelle mode (the Blue channel) at R=50,000 in a single exposure. The instrument is operated in a high vacuum (about 1 micro torr) and cryogenic temperatures (the bench at 189K and the detector at 87K) and with a precise temperature control. It is primarily used for high precision Doppler measurements (~3 m/s) of low mass M dwarf stars for the identification and characterization of extrasolar planets. A plan for a high cadence and high precision survey of habitable super-Earths around ~150 nearby M dwarfs and a major upgrade with integral field unit low resolution spectroscopy are also introduced.

Ge, Jian; Powell, Scott; Zhao, Bo; Schofield, Sidney; Varosi, Frank; Warner, Craig; Liu, Jian; Sithajan, Sirinrat; Avner, Louis; Jakeman, Hali; Gittelmacher, Jakob A.; Yoder, William A.; Muterspaugh, Matthew; Williamson, Michael; Maxwell, J. E.

2014-07-01

55

Comparison of a transmission grating spectrometer to a reflective grating spectrometer for standoff laser-induced breakdown spectroscopy measurements  

SciTech Connect

We evaluate a new transmission grating spectrometer for standoff laser-induced breakdown spectroscopy (LIBS) measurements. LIBS spectra collected from standoff distances are often weak, with smaller peaks blending into the background and noise. Scattered light inside the spectrometer can also contribute to poor signal-to-background and signal-to-noise ratios for smaller emission peaks. Further, collecting standoff spectra can be difficult because most spectrometers are designed for laboratory environments and not for measurements in the field. To address these issues, a custom-designed small, lightweight transmission grating spectrometer with no moving parts was built that is well suited for standoff LIBS field measurements. The performance of the spectrometer was quantified through 10 m standoff LIBS measurements collected from aluminum alloy samples and measurements from spectra of a Hg-Ar lamp. The measurements were compared to those collected using a Czerny-Turner reflective grating spectrometer that covered a similar spectral range and used the same ICCD camera. Measurements using the transmission grating spectrometer had a 363% improved signal-to-noise ratio when measured using the 669 nm aluminum emission peak.

Weisberg, Arel; Craparo, Joseph; De Saro, Robert; Pawluczyk, Romuald

2010-05-01

56

A field-portable thermal infrared grating spectrometer (THIRSPEC)  

Microsoft Academic Search

A thermal infrared grating spectrometer was developed for field studies in the Earth sciences. The design is based on a reflection grating and a 60-element HgCdTe detector array. The useful spectral range of the instrument covers 7.9-11.3 ?m with a Nyquist limited resolution of 0.16 ?m. The instrument averages over a 12 field of view and compares the exitance of

Benoit Rivard; Paul J. Thomas; D. Pollex; A. Hollinger; John R. Miller; R. Dick

1994-01-01

57

Source Scanning Type X-Ray Grating Spectrometer  

Microsoft Academic Search

A method is proposed for designing an x-ray spectrometer which can scan a limited wavelength region without movement of the concave grating or the electronic counter. Spectrometers widely used in the past have consisted of a fixed x-ray source and a movable counter. This method is to use a fixed counter and a scanning x-ray source to avoid undesirable movement

Masao Sawada; Kenjiro Tsutsumi

1969-01-01

58

The polarisation correction for space-borne grating spectrometers  

NASA Astrophysics Data System (ADS)

Satellite measurements of backscattered sunlight contain essential information about the global distribution of atmospheric constituents. Light reflected from the Earth's atmosphere is linearly or partially linearly polarized because of scattering of unpolarized sunlight by air molecules and aerosols. In the ultraviolet and visible part of the spectrum, measurements of space-borne grating spectrometers are in general sensitive to the state of polarization of the observed light. The interaction of polarized light with polarization-sensitive optical devices yields a different radiance that is measured by the detectors than the radiance that enters the instrument. In the OMI and the SBUV/2 instruments the problem of instrument polarization sensitivity is avoided because the polarized backscattered sunlight is depolarized before it interacts with the polarization-sensitive optical components. For GOME, SCIAMACHY, and GOME-2 it is intended to eliminate the polarization response of the instrument from the polarization-sensitive measurement. This paper discusses the basic concept of the polarisation correction of the space-borne grating spectrometers by using Mueller matrix calculus. A model was developed using the Mueller Matrices formulation to evaluate the polarization sensitivity of the space-borne grating spectrometers. The optical components are treated as general diattenuators with phase retardance. The correction for this polarization sensitivity is based on broadband polarization measurements. Accurate preflight polarisation calibration of space-borne grating spectrometers is essential for the observational objectives of the instrument, and a special facility has been developed in order to allow the instrument to be calibrated.

Zhao, Fa-cai; Sun, Quan-she; Chen, Kun-feng; Zhu, Xing-bang; Wang, Shao-shui; Wang, Guo-quan; Zheng, Xiang-liang; Han, Zhong

2014-02-01

59

An X-ray Grating Spectrometer for the ISS  

NASA Astrophysics Data System (ADS)

We present the design approach for a X-ray grating spectrometer mission to be deployed on the International Space Station. The baseline design uses sub-apertured X-ray optics feeding into off-plane gratings to achieve both high spectral resolution with a large effective area; the read out is by high-TRL CCDs in the focal plane. The mission will use a pointing system with a novel technology to reduce vibrations from the ISS propagating into the telescope, and would be ready to be attached to the ISS in 2021. The mission parameters are similar to those of the IXO X-ray Grating Spectrometer of R=3000 and ~1000 sq. cm at 0.5 keV, with a bandpass from ~0.3-1 keV, enabling a wide range of science objectives.

Bookbinder, Jay A.; McEntaffer, Randall L.; Daigneau, Peter; Smith, Randall K.; Bautz, Mark W.; Burrows, David N.; Willingale, Richard; Petre, Robert; Wilms, Jrn; Falcone, Abraham; Brickhouse, Nancy S.; Ptak, Andrew; Foster, Adam; Bregman, Joel N.

2014-06-01

60

Spectrometer concept and design for X-ray astronomy using a blazed transmission grating  

E-print Network

Spectrometer concept and design for X-ray astronomy using a blazed transmission grating Kathryn grating schemes considered in the past1,2,3 . The spectrometer readout is based on conventional CCD high spectral resolution in the soft X-ray band, employing grating spectrometers of sufficient

61

A filter free dual transmission grating spectrometer for the extreme-ultraviolet  

E-print Network

A filter free dual transmission grating spectrometer for the extreme- ultraviolet Seth R. Wieman of a prototype dual-grating filter-free extreme ultraviolet (EUV) spectrometer that has potential as a highly gratings of the type used in our spectrometer are the subject of considerable previous research4

Didkovsky, Leonid

62

Immersion echelle spectrograph  

SciTech Connect

A small spectrograph is disclosed containing no moving components and capable of providing high resolution spectra of the mid-infrared region from 2 microns to 4 microns in wavelength. The resolving power of the spectrograph exceeds 20,000 throughout this region and at an optical throughput of about 10{sup {minus}5}cm{sup 2}sr. The spectrograph incorporates a silicon immersion echelle grating operating in high spectral order combined with a first order transmission grating in a cross-dispersing configuration to provide a two-dimensional (2-D) spectral format that is focused onto a two-dimensional infrared detector array. The spectrometer incorporates a common collimating and condensing lens assembly in a near aberration-free axially symmetric design. The spectrometer has wide use potential in addition to general research, such as monitoring atmospheric constituents for air quality, climate change, global warming, as well as monitoring exhaust fumes for smog sources or exhaust plumes for evidence of illicit drug manufacture.

Stevens, C.G.; Thomas, N.L.

2000-06-20

63

"The Reflection Grating Spectrometer on Constellation-X"  

NASA Technical Reports Server (NTRS)

The Constellation-X Reflection Grating Spectrometer (RGS) is designed to provide high-throughput, high-resolution spectra in the long wavelength band of 6 to 50 angstrom. In the nominal design an array of reflection gratings is mounted at the exit of the Spectroscopy X-ray Telescope (SXT) mirror module. The gratings intercept and disperse light to a designated array of CCD detectors. To achieve the throughput (A_eff > 1000 cm2 below 0.6 keV) and resolution (R > 300 below 0.6 keV) requirements for the instrument we are investigating two possible grating designs. The first design uses in-plane gratings in a classical configuration that is very similar to the XMM-Newton RGS. The second design uses off-plane gratings in a conical configuration. The off-plane design has the advantage of providing higher reflectivity and potentially, a higher spectral resolution than the in-plane configuration. In our presentation we will describe the performance requirements and the current status of the technology development.

Cottam, J.

2006-01-01

64

ZEUS-2: a second generation submillimeter grating spectrometer for exploring distant galaxies  

E-print Network

ZEUS-2, the second generation (z)Redshift and Early Universe Spectrometer, like its predecessor is a moderate resolution (R~1000) long-slit, echelle grating spectrometer optimized for the detection of faint, broad lines from distant galaxies. It is designed for studying star-formation across cosmic time. ZEUS-2 employs three TES bolometer arrays (555 pixels total) to deliver simultaneous, multi-beam spectra in up to 4 submillimeter windows. The NIST Boulder-built arrays operate at ~100mK and are readout via SQUID multiplexers and the Multi-Channel Electronics from the University of British Columbia. The instrument is cooled via a pulse-tube cooler and two-stage ADR. Various filter configurations give ZEUS-2 access to 7 different telluric windows from 200 to 850 micron enabling the simultaneous mapping of lines from extended sources or the simultaneous detection of the 158 micron [CII] line and the [NII] 122 or 205 micron lines from z = 1-2 galaxies. ZEUS-2 is designed for use on the CSO, APEX and possibly JCM...

Ferkinhoff, Carl; Parshley, Stephen C; Stacey, Gordon J; Irwin, Kent D; Cho, Hsiao-Mei; Halpern, Mark; 10.1117/12.857018

2010-01-01

65

Cooled grating array spectrometer for 0.6-5 microns  

NASA Technical Reports Server (NTRS)

A grating spectrometer, designed to illuminate an array of 122 InSb photodiodes with minimum aberrations and maximum speed, has been constructed. The instrument will be used on the 5 meter Hale telescope at Palomar Observatory, and is easily adaptable to telescopes of various focal ratios. A resolving power of 100-1000 can be obtained at wavelengths between 0.6 microns and 5 microns with remotely interchangeable gratings. The spectrometer is sufficiently compact to fit on the 8-inch work surface of a commercially available dewar, and uses simple on-axis spherical and paraboloidal optical elements. The camera mirror produces an f/2.5 beam which, with the 0.2 mm detectors, allows a 3-in. focal-plane aperture on the 5 meter telescope. All rays fall within a 100 microns blur circle at all points along the array. Distortions have been corrected with a tilted field flattening lens in front of the detector.

Nordholt, J. E.; Lacy, J. H.

1982-01-01

66

The Reflection Grating Spectrometer on board XMM-Newton  

Microsoft Academic Search

The ESA X-ray Multi Mirror mission, XMM-Newton, carries two identical Reflection Grating Spectrometers (RGS) behind two of its three nested sets of Wolter I type mirrors. The instrument allows high-resolution (E\\/Delta E = 100 to 500) measurements in the soft X-ray range (6 to 38 , or 2.1 to 0.3 keV) with a maximum effective area of about 140 cm2

J. W. den Herder; A. C. Brinkman; S. M. Kahn; G. Branduardi-Raymont; K. Thomsen; H. Aarts; M. Audard; J. V. Bixler; A. J. den Boggende; J. Cottam; T. Decker; L. Dubbeldam; C. Erd; H. Goulooze; M. Gdel; P. Guttridge; C. J. Hailey; K. Al Janabi; J. S. Kaastra; P. A. J. de Korte; B. J. van Leeuwen; C. Mauche; A. J. McCalden; R. Mewe; A. Naber; F. B. Paerels; J. R. Peterson; A. P. Rasmussen; K. Rees; I. Sakelliou; M. Sako; J. Spodek; M. Stern; T. Tamura; J. Tandy; C. P. de Vries; S. Welch; A. Zehnder

2001-01-01

67

Solar Imaging UV/EUV Spectrometers Using TVLS Gratings  

NASA Technical Reports Server (NTRS)

It is a particular challenge to develop a stigmatic spectrograph for UV, EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both reimaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar extreme ultraviolet (EUV) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets Solar Extreme ultraviolet Research Telescope and Spectrograph (SERTS) and Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS). More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of three new solar spectrometers based on this concept are described: SUMI and RAISE, two sounding rocket payloads, and NEXUS, currently being proposed as a Small-Explorer (SMEX) mission.

Thomas, Roger J.

2003-01-01

68

New grating designs for a CTIS imaging spectrometer Nathan Hagena, Eustace L. Dereniaka  

E-print Network

New grating designs for a CTIS imaging spectrometer Nathan Hagena, Eustace L. Dereniaka a pattern is then replicated over the clear aperture to produce the final grating design.3 slit spectrometerOptical Sciences Center, University of Arizona, Tucson, AZ 85721 ABSTRACT We present some new grating designs

Dereniak, Eustace L.

69

Description and performance of the reflection grating spectrometer on board of XMMNewton  

E-print Network

Description and performance of the reflection grating spectrometer on board of XMM­Newton J.W. den early 2000. First results for the Reflection Grating Spectrometers will be presented concentrating e Paul Sherrer Institute, CH­5232 Villigen, Switzerland ABSTRACT The Reflection Grating

Guedel, Manuel

70

Design of a hybrid-integrated MEMS scanning grating spectrometer  

NASA Astrophysics Data System (ADS)

Optical MEMS (micro electro mechanical systems) have been used to reduce size, weight and costs of any kind of optical systems very successfully starting in the last decades. Scientists at Fraunhofer IPMS invented a resonant drive for 1-d and 2-d MEMS scanning mirror devices. Besides mirrors also scanning gratings have been realized. Now, rapidly growing new applications demand for enhanced functions and further miniaturization. This task cannot be solved by simply putting more functionality into the MEMS chip, for example grating and slit structures, but by three dimensional hybrid integration of the complete optical system into a stack of several functional substrates. Here we present the optical system design and realization strategy for a scanning grating spectrometer for the near infrared (NIR) range. First samples will be mounted from single components by a bonder tool (Finetech Fineplacer Femto) but the option of wafer assembly will be kept open for future developments. Extremely miniaturized NIR spectrometer could serve a wide variety of applications for handheld devices from food quality analysis to medical services or materials identification.

Pgner, Tino; Knobbe, Jens; Grger, Heinrich; Schenk, Harald

2011-10-01

71

Chirped holographic grating used as the dispersive element in an optical spectrometer  

SciTech Connect

We have developed a new design of optical spectrometer based on the use of a chirped holographic grating inscribed on a flat substrate. This type of grating has a surface modulation with a spatially varying period. The ability of the chirped grating to focus a beam is exploited to reduce significantly the physical dimensions of the instrument. Wavelength selection is achieved by a pure translation of the chirped grating. The properties of the chirped grating spectrometer have been characterized with different lasers and arc lamps and compared with those of two commercial spectrometers. A performance parameter has been defined, enabling the various instruments to be compared.

Fortin, Gilles; McCarthy, Nathalie

2005-08-10

72

Development of a Submillimeter-Wavelength Immersion Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The broad goal of this project was to develop a broadband, moderate-resolution spectrometer for submillimeter wavelengths. Our original approach was to build an immersion grating spectrometer, and as such, the first step was to identify the best material (lowest loss, highest index) for the grating medium, and to characterize its properties at the foreseen optical-bench operating temperature of 1.5 K. To this end, we put our initial efforts into upgrading an existing laboratory submillimeter Fourier transform spectrometer, which allowed us to carry out the requisite materials measurements. The associated cryogenic detector dewar was also redesigned and rebuilt to carry out this work. This dewar houses the 1.5 K detector and the filter wheel used in the materials characterization. Our goal was to have the beam propagate through the samples as uniformly as possible, so the optics were redesigned to allow for the samples to be traversed by a well-defined collimated beam. The optics redesign also placed the samples at an image of the aperture stop located within the FTS. After the rebuild, we moved into the testing phase.

Phillips, T. G.

2001-01-01

73

The Spectrometer Objective: In this lab, you will calibrate a diffraction grating and use it to make a  

E-print Network

The Spectrometer Objective: In this lab, you will calibrate a diffraction grating and use and transmission grating. In this lab, we will use the transmission grating. However, most commercial spectrometers it to make a spectrometer. Once you have built the spectrometer, it's yours to keep! Someday when you have

Collins, Gary S.

74

Determination of barium in seawater by a standard addition method adapted to the direct current echelle optical emission spectrometer  

SciTech Connect

A technique for determining trace concentrations of barium in seawater is described. Analyses are performed using an optical emission spectrometer/spectrograph equipped with an echelle monochromator and a dc argon plasma excitation source. Calibration is done by the addition method. Three portions of each sample are used for each determination. Each of these is mixed in a 9:1 volumetric ratio with a solution containing 2% (w/v) lithium and either 0, 200, or 400 ..mu..g of barium per liter. The instrumental response to 0 ..mu..g of barium per liter is estimated using a 0.2% (w/v) solution of lithium in deionized distilled water as a blank. The accuracy of results obtained in this study is assessed by comparing them with replicate data previously obtained by another investigator using isotope dilution mass spectrometry. The detection limit of the present method is approx. 2 ..mu..g/L. Near this limit, the RSD ranged from 13 to 27%.

Bankston, D.C.

1980-01-01

75

The Reflection Grating Spectrometer on board XMM A. Brinkman, H. Aarts, A. den Boggende, T. Bootsma, L. Dubbeldam, J. den Herder, J. Kaastra,  

E-print Network

-- 1 -- The Reflection Grating Spectrometer on board XMM A. Brinkman, H. Aarts, A. den Boggende, T Scherrer Institute, CH­5232 Villigen, Switzerland ABSTRACT The Reflection Grating Spectrometer (RGS. Introduction While discussing the spectroscopic capabilities of the Reflection Grating Spectrometer (RGS

Guedel, Manuel

76

Design and early performance of IGRINS (Immersion Grating Infrared Spectrometer)  

NASA Astrophysics Data System (ADS)

The Immersion Grating Infrared Spectrometer (IGRINS) is a compact high-resolution near-infrared cross-dispersed spectrograph whose primary disperser is a silicon immersion grating. IGRINS covers the entire portion of the wavelength range between 1.45 and 2.45?m that is accessible from the ground and does so in a single exposure with a resolving power of 40,000. Individual volume phase holographic (VPH) gratings serve as cross-dispersing elements for separate spectrograph arms covering the H and K bands. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is 1? x 15? and the plate scale is 0.27? pixel. The spectrograph employs two 2048 x 2048 pixel Teledyne Scientific and Imaging HAWAII-2RG detectors with SIDECAR ASIC cryogenic controllers. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be only 25mm, which permits a moderately sized (0.96m x 0.6m x 0.38m) rectangular cryostat to contain the entire spectrograph. The fabrication and assembly of the optical and mechanical components were completed in 2013. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present early performance test results obtained from the commissioning runs at the McDonald Observatory.

Park, Chan; Jaffe, Daniel T.; Yuk, In-Soo; Chun, Moo-Young; Pak, Soojong; Kim, Kang-Min; Pavel, Michael; Lee, Hanshin; Oh, Heeyoung; Jeong, Ueejeong; Sim, Chae Kyung; Lee, Hye-In; Nguyen Le, Huynh Anh; Strubhar, Joseph; Gully-Santiago, Michael; Oh, Jae Sok; Cha, Sang-Mok; Moon, Bongkon; Park, Kwijong; Brooks, Cynthia; Ko, Kyeongyeon; Han, Jeong-Yeol; Nah, Jakyoung; Hill, Peter C.; Lee, Sungho; Barnes, Stuart; Yu, Young Sam; Kaplan, Kyle; Mace, Gregory; Kim, Hwihyun; Lee, Jae-Joon; Hwang, Narae; Park, Byeong-Gon

2014-07-01

77

In-flight calibration of the Chandra high-energy transmission grating spectrometer  

Microsoft Academic Search

We present results from in-flight calibration of the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory. Basic grating assembly parameters such as orientation and average grating period were measured using emission line sources. These sources were also used to determine the locations of individual CCDs within the flight detector. The line response function (LRF) was modeled in

Herman L. Marshall; Daniel Dewey; Kazunori Ishibashi

2004-01-01

78

Calibration of an extreme-ultraviolet transmission grating spectrometer with synchrotron radiation  

Microsoft Academic Search

The responsivity of an extreme-ultraviolet transmission grating spectrometer with silicon photodiode detectors was measured with synchrotron radiation. The spectrometer was designed to record the absolute radiation flux in a wavelength bandpass centered at 30 nm. The transmission grating had a period of 200 nm and relatively high efficiencies in the 11 and the 21 diffraction orders that were dispersed on

John F. Seely; Charles M. Brown; Glenn E. Holland; Frederick Hanser; John Wise; James L. Weaver; Raj Korde; Rodney A. Viereck; Richard Grubb; Darrell L. Judge

2001-01-01

79

Transmission Grating Spectrometer for Constellation-X White paper response to NASA solicitation 210S-GBG-06-001  

E-print Network

1 Transmission Grating Spectrometer for Constellation-X White paper response to NASA solicitation 2006 1. Introduction and Overview of the Transmission Grating Spectrometer (TGS) This white paper proposes a transmission grating spectrometer to provide high spectral resolution at low energies, extending

Heilmann, Ralf

80

Initial Results From The Chandra High Energy Transmission Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory provides spectral resolving powers of 200-1000 over the range 0.4-8.0 keV (1.5-30 A) with effective area of 2-200 square centimeters. Initial observations during the activation and calibration phases of the mission show that the HETGS is performing as predicted prior to Chandra launch. The talk presented very preliminary results that illustrate the power of the HETGS for performing detailed studies of a wide range of celestial sources, including plasma diagnostics. This written version gives a brief summary of that talk with examples of preliminary spectra of Capella, the Crab pulsar, SS433 and the SNR E0102-72.

Canizares, C. R.; Davis, D. S.; Dewey, D.; Flanagan, K. A.; Houck, J.; Huenemoerder, D. P.; Marshall, H. L.; Schattenburg, M. L.; Schulz, N. S.; Wise, M.

2000-01-01

81

The Reflection Grating Spectrometer on Board XMM-Newton  

NASA Technical Reports Server (NTRS)

The ESA X-ray Multi Mirror mission, XMM-Newton, carries two identical Reflection Grating Spectrometers (RGS) behind two of its three nested sets of Wolter I type mirrors. The instrument allows high-resolution (E/(Delta)E = 100 to 500) measurements in the soft X-ray range (6 to 38 A or 2.1 to 0.3 keV) with a maximum effective area of about 140 sq cm at 15 A. Its design is optimized for the detection of the K-shell transitions of carbon, nitrogen, oxygen, neon, magnesium, and silicon. as well as the L shell transitions of iron. The present paper gives a full description of the design of the RGS and its operational modes. We also review details of the calibrations and in-orbit performance including the line spread function, the wavelength calibration, the effective area, and the instrumental background.

denHerder, J. W.; Brinkman, A. C.; Kahn, S. M.; Branduardi-Raymont, G.; Thomsen, K.; Aarts, H.; Audard, M.; Bixler, J. V.; denBoggende, A. J.

2000-01-01

82

Design of a novel transmission-grating spectrometer for soft X-ray emission studies  

Microsoft Academic Search

The design of a transmission-grating spectrometer for high-resolution soft X-ray emission studies has been proposed. It is different from conventional types of soft X-ray emission spectrometers; that is, the spectrometer has a Wolter type I mirror, a free-standing transmission grating, and a back-illuminated CCD. A high collection angle up to 1.510?3sr is achieved by utilizing the Wolter mirror as a

Takaki Hatsui; Hiroyuki Setoyama; Eiji Shigemasa; Nobuhiro Kosugi

2005-01-01

83

A simple scanning spectrometer based on a stretchable elastomeric reflective grating  

NASA Astrophysics Data System (ADS)

We report a scanning optical spectrometer based on the use of a stretchable elastomeric reflective grating. The grating is obtained by supersonic cluster beam implantation of silver nanoparticles on polydimethylsiloxane previously grooved by molding to create a replica of a commercial digital versatile disk grating. The use of a stretchable grating allows the spectrometer spanning the whole optical wavelength range by solely extending the diffraction element by more than 100% of its original dimensions. The stretchable reflective optical grating shows excellent performances and stability upon thousands of stretching cycles. The use of this elastomeric element makes the optical layout and the mechanics of the spectrometer extremely simple and advantageous for those applications where spectral resolution is not a major requirement. As a proof of principle, we present the absorption spectrum of Rhodamine B in solution obtained by our spectrometer and compared to commercial instruments.

Ghisleri, C.; Potenza, M. A. C.; Ravagnan, L.; Bellacicca, A.; Milani, P.

2014-02-01

84

[EUV flat field grating spectrometer and performance measurement].  

PubMed

A high-resolution extreme ultraviolet (EUV) spectrometer has been developed to diagnose the magnetically confined plasmas. A holographic spherical varied line spacing concave grating which provides a flat focal plane is used as the diffraction element working with the grazing incidence angle of 3 degrees. The nominal groove density is 1200 lines x mm(-1). A deeply cooled back-illuminated CCD camera is used as the spectra detector and a mechanical shutter is used to control the time of exposure. It covers the wavelength range of 5-50 nm with the CCD cameral moving along the spectra focal plane to cover different wavelength range interested. Spectrometer design is presented and it was tested by a Penning discharge light source. By the wavelength calibration, the actual parameters of the optical system were calculated and the wavelength accuracy is 0.003 nm. Results show that the spectral resolution is about 0.015 nm at 20 nm with the width of entrance slit opened at 30 microm, which agrees with the design goal. PMID:23156796

Du, Xue-wei; Shen, Yong-cai; Li, Chao-yang; An, Ning; Shi, Yue-jiang; Wang, Qiu-ping

2012-08-01

85

A liquid-helium-cooled grating spectrometer for far infrared astronomical observations  

NASA Technical Reports Server (NTRS)

A liquid-helium-cooled grating spectrometer has been developed for low-resolution far-infrared spectrometric measurements of astronomical sources conducted by the 30-cm NASA Lear Jet telescope. Simple MOSFET coupled transimpedance preamplifiers were adopted for the spectrometer design. The infrared spectrometer has resolving powers from 10 to 150 over the wavelength range from 45 to 115 microns.

Houck, J. R.; Ward, D.

1979-01-01

86

High resolution Florida IR silicon immersion grating spectrometer and an M dwarf planet survey  

NASA Astrophysics Data System (ADS)

We report the system design and predicted performance of the Florida IR Silicon immersion grating spectromeTer (FIRST). This new generation cryogenic IR spectrograph offers broad-band high resolution IR spectroscopy with R=72,000 at 1.4-1.8 ?m and R=60,000 at 0.8-1.35 ?m in a single exposure with a 2kx2k H2RG IR array. It is enabled by a compact design using an extremely high dispersion silicon immersion grating (SIG) and an R4 echelle with a 50 mm diameter pupil in combination with an Image Slicer. This instrument is operated in vacuum with temperature precisely controlled to reach long term stability for high precision radial velocity (RV) measurements of nearby stars, especially M dwarfs and young stars. The primary technical goal is to reach better than 4 m/s long term RV precision with J<9 M dwarfs within 30 min exposures. This instrument is scheduled to be commissioned at the Tennessee State University (TSU) 2-m Automatic Spectroscopic Telescope (AST) at Fairborn Observatory in spring 2013. FIRST can also be used for observing transiting planets, young stellar objects (YSOs), magnetic fields, binaries, brown dwarfs (BDs), ISM and stars. We plan to launch the FIRST NIR M dwarf planet survey in 2014 after FIRST is commissioned at the AST. This NIR M dwarf survey is the first large-scale NIR high precision Doppler survey dedicated to detecting and characterizing planets around 215 nearby M dwarfs with J< 10. Our primary science goal is to look for habitable Super-Earths around the late M dwarfs and also to identify transiting systems for follow-up observations with JWST to measure the planetary atmospheric compositions and study their habitability. Our secondary science goal is to detect and characterize a large number of planets around M dwarfs to understand the statistics of planet populations around these low mass stars and constrain planet formation and evolution models. Our survey baseline is expected to detect ~30 exoplanets, including 10 Super Earths, within 100 day periods. About half of the Super-Earths are in their habitable zones and one of them may be a transiting planet. The AST, with its robotic control and ease of switching between instruments (in seconds), enables great flexibility and efficiency, and enables an optimal strategy, in terms of schedule and cadence, for this NIR M dwarf planet survey.

Ge, Jian; Powell, Scott; Zhao, Bo; Wang, Ji; Fletcher, Adam; Schofield, Sidney; Liu, Jian; Muterspaugh, Matthew; Blake, Cullen; Barnes, Rory

2012-09-01

87

[Technology Development for X-Ray Reflection for the Constellation-X Reflection Grating Spectrometer (RGS)  

NASA Technical Reports Server (NTRS)

This Grant covers MIT support for the technology development of x-ray reflection gratings for the Constellation-X Reflection Grating Spectrometer (RGS). Since the start of the Grant MIT has extended its previously-developed patterning and super-smooth, blazed grating fabrication technology to ten-times smaller grating periods and ten-times larger blaze angles to demonstrate feasibility and performance in the off-plane grating geometry. In the past year we successfully developed several nanoimprint grating replication methods that achieved very high fidelity replication of master silicon gratings. Grating geometry on the nano and macro scales were faithfully replicated, demonstrating the viability of the process for manufacturing the thousands of gratings required for the RGS. We also successfully developed an improved metrology truss for holding test grating substrates during metrology. The flatness goal of grating substrates is under 500 nm. In the past, grating holders would cause non-repeatable distortion of >> 500 nm to the substrates due to friction and gravity sag. The new holder has a repeatability of under 50 nm which is adequate for the proposed RGS grating substrates.

Schattenburg, Mark L.

2003-01-01

88

Integrated arrayed waveguide grating spectrometer for on-chip optical coherence tomography  

Microsoft Academic Search

A silicon oxynitride based arrayed waveguide grating spectrometer was designed for on-chip spectral-domain optical coherence tomography systems. Transmission measurement results are promising for miniaturizing the current optical coherence tomography systems through integrated optics.

I. Akca; N. Ismail; F. Sun; V. D. Nguyen; J. Kalkman; T. G. van Leeuwen; A. Driessen; K. Worhoff; M. Pollnau; R. M. de Ridder

2010-01-01

89

Development of a critical-angle transmission grating spectrometer for the International X-Ray Observatory  

E-print Network

We present a high-resolution soft x-ray grating spectrometer concept for the International X-Ray Observatory (IXO) that meets or exceeds the minimum requirements for effective area (> 1, 000 cm[superscript 2] for E < 1 ...

Smith, Matthew

90

A Soft X-ray Spectrometer using a Highly Dispersive Multilayer Grating  

SciTech Connect

There is a need for higher resolution spectrometers as a tool for inelastic x-ray scattering. Currently, resolving power around R = 10,000 is advertised. Measured RIXS spectra are often limited by this instrumental resolution and higher resolution spectrometers using conventional gratings would be prohibitively large. We are engaged in a development program to build blazed multilayer grating structures for diffracting soft x-rays in high order. This leads to spectrometers with dispersion much higher than is possible using metal coated-gratings. The higher dispersion then provides higher resolution and the multilayer gratings are capable of operating away from grazing incidence as required. A spectrometer design is presented with a total length 3.8 m and capable of 10{sup 5} resolving power.

Warwick, Tony; Padmore, Howard; Voronov, Dmitriy; Yashchuk, Valeriy [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA94720 (United States)

2010-06-23

91

A high-resolution grating spectrometer for the infra-red region  

Microsoft Academic Search

A grating spectrometer designed on an Ebert mounting has been constructed which, with suitable photoconductive cells and a 6 6 in. N.P.L. grating, gives a resolution of 0.1 cm-1 in the range 6000 to 1700 cm-1. It covers the region 600 to 10 000 cm-1 with a single grating and is as simple to operate as a conventional prism

M A Ford; W C Price; G R Wilkinson

1958-01-01

92

Soft X-ray response of a CCD with a grating spectrometer  

Microsoft Academic Search

We calibrate the X-ray imaging spectrometers, which are CCD cameras installed on the ASTRO-E satellite, by using dispersed continuous soft X-rays from a grating spectrometer. We obtained the signal-pulse height and energy-resolution as a function of X-ray energies continuously. However, the wings of the line spread function of the grating distorts the center of the signal-pulse height derived by a

M. Shouho; K. Katayama; H. Katayama; T. Kohmura; H. Tsunemi; S. Kitamoto; K. Hayashida; E. Miyata; K. Hashimotodani; K. Yoshita; K. Koyama; G. Ricker; M. W. Bautz; R. Foster; S. Kissel

1999-01-01

93

Design and experiment of spectrometer based on scanning micro-grating integrating with angle sensor  

NASA Astrophysics Data System (ADS)

A compact, low cost, high speed, non-destructive testing NIR (near infrared) spectrometer optical system based on MOEMS grating device is developed. The MOEMS grating works as the prismatic element and wavelength scanning element in our optical system. The MOEMS grating enables the design of compact grating spectrometers capable of acquiring full spectra using a single detector element. This MOEMS grating is driven by electromagnetic force and integrated with angle sensor which used to monitored deflection angle while the grating working. Comparing with the traditional spectral system, there is a new structure with a single detector and worked at high frequency. With the characteristics of MOEMS grating, the structure of the spectrometer system is proposed. After calculating the parameters of the optical path, ZEMAX optical software is used to simulate the system. According the ZEMAX output file of the 3D model, the prototype is designed by SolidWorks rapidly, fabricated. Designed for a wavelength range between 800 nm and 1500 nm, the spectrometer optical system features a spectral resolution of 16 nm with the volume of 97 mm 81.7 mm 81 mm. For the purpose of reduce modulated effect of sinusoidal rotation, spectral intensity of the different wavelength should be compensated by software method in the further. The system satisfies the demand of NIR micro-spectrometer with a single detector.

Biao, Luo; Wen, Zhi-yu

2014-01-01

94

Design of optical system for spectrometer involving a volume phase holographic transmission grating  

NASA Astrophysics Data System (ADS)

At present, spectrometer has popularly being used into varieties of fields including environment, food, medical health monitoring and metal industry because it has the advantages of noninvasive, high efficient and convenient etc. The performance of the spectrometer is determined by its optical system. Normally, according to the apparatus and principle of splitting-light, optical system of spectrometer can be classified into several categories, for example, filter-typed, dispersion typed, Fourier transform typed and acousto-optic tunable typed. The grating typed optical system has been popularly used into the spectrometer due to the features of higher diffraction efficiency, resolution and dispersion rate etc. In the grating-typed optical system, although the traditional plane and concave grating have usually been used into some spectrometers, some disadvantages of them still limit their applications, such as, large aberration, worse spectral flatness and low deficiency, etc. In this paper, to overcome these disadvantages of the traditional plane and concave grating, a novel optical system for spectrometer (OSS) based on volume phase holographic transmission (VPHT) grating was designed. For this novel grating, its manufacture and theories were investigated, and its diffraction efficiency was firstly numerically simulated according to different parameters. In order to prove the feasibility of this designed OSS, the spectral calibration experiment was performed and the spectral resolution reached 2nm.

Ren, Zhong; Liu, Guodong; Huang, Zhen

2014-08-01

95

Passive Spectroscopy Bolometers, Grating- And X-ray Imaging Crystal Spectrometers  

SciTech Connect

This tutorial gives a brief introduction into passive spectroscopy and describes the working principles of bolometers, a high-resolution grating spectrometer, and a novel X-ray imaging crystal spectrometer, which is also of particular interest for profile measurements of the ion temperature and plasma rotation velocity on ITER and future burning plasma experiments.

Bitter, M.; Hill, K. W.; Scott, S.; Paul, S. [Princeton Plasma Physics Laboratory, Princeton, NJ, 08543 (United States); Ince-Cushman, A.; Reinke, M.; Rice, J. E. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Beiersdorfer, P.; Gu, M. F. [Lawrence Livermore national Laboratory, Livermore, CA 94550-9234 (United States); Lee, S. G. [Korea Basic Science Institute, Taejeon 305-333 (Korea, Republic of); Broennimann, Ch.; Eikenberry, E. F. [Paul Scherrer Institut, CH5232 Villigen-PSI (Switzerland)

2008-03-12

96

Passive Spectroscopy Bolometers, Grating- And X-Ray Imaging Crystal Spectrometers  

SciTech Connect

This tutorial gives a brief introduction into passive spectroscopy and describes the working principles of bolometers, a high-resolution grating spectrometer, and a novel X-ray imaging crystal spectrometer, which is of particular interest for profile measurements of the ion temperature and plasma rotation velocity on ITER and future burning plasma experiments.

Bitter, M; Hill, K W; Scott, S; Paul, S; Ince-Cushmann, A; Reinke, M; Rice, J; Beiersdorfer, P; Gu, M F; Lee, S G; Broennimann, C; Eikenberry, E F

2007-11-07

97

High resolution interrogation technique based on linear photodiode array spectrometer for fiber Bragg grating sensors  

Microsoft Academic Search

A linear photodiode array spectrometer based, high resolution interrogation technique for fiber Bragg grating sensors is demonstrated. Spline interpolation and Polynomial Approximation Algorithm (PAA) are applied to the data points acquired by the spectrometer to improve the original PAA based interrogation method. Thereby fewer pixels are required to achieve the same resolution as original. Theoretical analysis indicates that if the

Songwei Zhang; Yuliang Liu; Fang Li

2007-01-01

98

Numerical optimization of spherical variable-line-spacing grating X-ray spectrometers  

PubMed Central

Operation of an X-ray spectrometer based on a spherical variable-line-spacing (VLS) grating is analyzed using dedicated ray-tracing software allowing fast optimization of the grating parameters and spectrometer geometry. The analysis is illustrated with optical design of a model spectrometer to deliver a resolving power above 20400 at a photon energy of 930?eV (Cu L-edge). With this energy taken as reference, the VLS coefficients are optimized to cancel the lineshape asymmetry (mostly from the coma aberrations) as well as minimize the symmetric aberration broadening at large grating illuminations, dramatically increasing the aberration-limited vertical acceptance of the spectrometer. For any energy away from the reference, corrections to the entrance arm and light incidence angle on the grating are evaluated to maintain the exactly symmetric lineshape. Furthermore, operational modes when these corrections are coordinated are evaluated to maintain either energy-independent focal curve inclination or maximal aberration-limited spectrometer acceptance. The results are supported by analytical evaluation of the coma term of the optical path function. This analysis thus gives a recipe for designing a high-resolution spherical VLS grating spectrometer operating with negligible aberrations at large acceptance and over an extended energy range. PMID:21335898

Strocov, V. N.; Schmitt, T.; Flechsig, U.; Patthey, L.; Chiuzb?ian, G. S.

2011-01-01

99

Fundamental limits to slow-light arrayed-waveguide-grating spectrometers.  

PubMed

We present an analytical model that describes the limiting spectral performance of arrayed-waveguide-grating (AWG) spectrometers that incorporate slow-light methods. We show that the loss-limited spectral resolution of a slow-light grating-based spectrometer scales as the loss-group-index ratio of the waveguide array. We further show that one can achieve a spectral resolution of a few GHz using currently available slow-light photonic crystal waveguides while greatly shrinking the on-chip footprint of the spectrometer. PMID:23546160

Shi, Zhimin; Boyd, Robert W

2013-03-25

100

Development of two-grating spectrometer for the charge exchange spectroscopy system on KSTAR  

NASA Astrophysics Data System (ADS)

The charge exchange spectroscopy (CES) system on Korea Superconducting Tokamak Advanced Research (KSTAR) was installed last year and had been applied to measure the C VI ion temperature and rotation velocity profiles. The ion temperature and rotation velocity profiles had been estimated from the C VI 5290.5 (n = 8-7) charge-exchange spectrum signal measured by a Czerny-Turner type spectrometer and a thinned back-illuminated charge coupled device (CCD) camera. However, the Czerny-Turner type spectrometer used for the KSTAR CES system showed so low signal to noise ratio for KSTAR plasmas in the 2010 experimental campaign that the time resolution of the CES system had been limited to 100 ms due to the increased exposure time of the attached CCD camera. Then, new two-grating spectrometer had been developed in order to improve the time resolution of the CES system. The spectrometer consists of two gratings (1200 g/mm and 1800 g/mm each) with additive configuration, concave mirrors (f = 50 cm), and a cylindrical lens (f = 50 cm). The time resolution of the CES system increases by a factor of 2-4 with the two-grating spectrometer. The C VI ion temperature and rotation velocity profiles obtained by the two-grating spectrometer are compared to those by Czerny-Turner type spectrometer in this paper.

Lee, Hyungho; Song, Eun-ji; Park, Young-dong; Oh, Soo-ghee; Ko, Won-Ha

2011-06-01

101

Direct detection submillimeter spectrometer for CCAT  

Microsoft Academic Search

We present a trade study for a submillimeter direct-detection spectrometer operating at the background limit for the Cornell Caltech Atacama Telescope (CCAT). In this study we compare the classical echelle spectrometer ZEUS with the waveguide grating spectrometer Z-Spec. The science driver for this instrument is spectroscopic investigation of high redshift galaxies as their far-IR fine structure line emission is redshifted

Thomas Nikola; Gordon J. Stacey; C. Matt Bradford

2008-01-01

102

A Novel Active Grating Monochromator - Active Grating Spectrometer Beamline System for Inelastic Soft-X-ray Scattering Experiments  

SciTech Connect

By using two aspherical variable-line-space active gratings and applying the energy compensation principle, we have designed a very efficient active grating monochromator -- active grating spectrometer (AGM-AGS) beamline system for the photon demanding inelastic soft-x-ray scattering experiments. During the energy scan, the defocus and coma aberrations of the AGM can be completely eliminated to make the focal point fixed at the sample position and to maintain high spectral resolution for the entire spectral range. The AGS, which has an optical system identical to that of the AGM, but positioned reversely along the optical path, collects the photons emitted from the sample with a nearly identical energy spread as the AGM and focus them onto a position sensitive detector located at the exit slit position. The ray tracing results show that the efficiency of the AGM-AGS is two orders of magnitudes higher than that of conventional design while maintaining a very high spectral resolution.

Fung, H.S.; Chen, C.T.; Huang, L.J.; Chang, C.H.; Chung, S.C.; Wang, D.J.; Tseng, T.C.; Tsang, K.L. [National Synchrotron Radiation Research Center, Hsinchu 30077, Taiwan (China)

2004-05-12

103

The super-gratings: How to improve the limiting resolution of grating spectrometers  

Microsoft Academic Search

An array of two coplanar gratings gives rise to a single high-dispersion element, which is here called super-grating. The possibility of realizing practically a super-grating is analyzed from a theoretical point of view. It is shown that the most critical parameter, i.e. the phase matching between the two elements, may be satisfactorily adjusted using available micropositioning systems.

V. Mazzacurati; G. Ruocco

1990-01-01

104

Hinge spectrometer - A grating Fabry-Perot instrument for far-infrared/submillimeter spectroscopy in space  

NASA Technical Reports Server (NTRS)

A compact submillimeter spectrometer can be constructed through the use of a combination of grating and Fabry-Perot techniques. The instrument has only one moving part, a grating that pivots about an accurately placed hinge. The entire optical train is cooled to liquid helium temperature for low-background low-noise operation and is designed for use in astronomical observations from aircraft, balloons, or space vehicles. Resolving power R about 20,000 at about 150 microns is demonstrated.

Harwit, Martin; Fuller, Charles; Viscuso, Paul J.; Stacey, Gordon J.

1987-01-01

105

Imaging extreme ultraviolet spectrometer employing a single toroidal diffraction grating - The initial evaluation  

NASA Technical Reports Server (NTRS)

The design and test results of a high-efficiency EUV imaging spectrometer employing a concave toroidal grating which is illuminated at normal incidence in a Rowland circle mounting and has only one reflecting surface are discussed. Photographic tests and initial photoelectric tests with a two-dimensional pulse-counting detector system demonstrate the excellent image quality of the grating at wavelengths near 600 A. Applications of the spectrometer for the study of nonsolar objects and solar regions (including the chromosphere, transition region, and corona) are considered.

Huber, M. C. E.; Timothy, J. G.; Morgan, J. S.; Lemaitre, G.; Tondello, G.

1988-01-01

106

Single-shot analysis of hard x-ray laser radiation using a noninvasive grating spectrometer.  

PubMed

We present a spectrometer setup based on grating dispersion for hard x-ray free-electron lasers. This setup consists of a focusing spectrometer grating and a charge-integrating microstrip detector. Measurement results acquired at Linac Coherent Light Source are presented, demonstrating noninvasive monitoring of single-shot spectra with a resolution of 2.010(-4) 0.310(-4) at photon energy of 6 keV with more than 95% transmission of the main beam. PMID:23258009

Karvinen, Petri; Rutishauser, Simon; Mozzanica, Aldo; Greiffenberg, Dominic; Jurani?, Pavle N; Menzel, Andreas; Lutman, Alberto; Krzywinski, Jacek; Fritz, David M; Lemke, Henrik T; Cammarata, Marco; David, Christian

2012-12-15

107

[Study on far ultraviolet imaging spectrometer with grating dispersion for atmosphere remote sensing].  

PubMed

The far ultraviolet imaging spectrometer with grating dispersion is mainly used in the detection of the ionosphere, thermosphere, auroral zone and glow zone. It is important for the study and application of the remote sensing of atmosphere in China. We designed two optical systems for the far ultraviolet imaging spectrometer, and obtained the plane grating structure prototype based on the principles of nadir and limb atmospheric sounding. The prototype working at the waveband of 120-180 nm consists of an off-axis parabolic mirror and an advanced Czerny-Turner spectral imaging system. The far ultraviolet response back-illuminating CCD is adopted as the detector. The corresponding experiment system was built to calibrate the basic performances of the spectrometer prototype. The spectral and spatial resolutions are 2 nm and 0.5 mrad respectively. The far ultraviolet imaging spectrometer prototype plays an important role in the study and application of atmospheric remote sensing. PMID:22582666

Yu, Lei; Wang, Shu-rong; Lin, Guan-yu; Qu, Yi; Wang, Long-qi

2012-03-01

108

Transmission grating based extreme ultraviolet imaging spectrometer for time and space resolved impurity measurements  

SciTech Connect

A free standing transmission grating based imaging spectrometer in the extreme ultraviolet range has been developed for the National Spherical Torus Experiment (NSTX). The spectrometer operates in a survey mode covering the approximate spectral range from 30 to 700 A and has a resolving capability of {delta}{lambda}/{lambda} on the order of 3%. Initial results from space resolved impurity measurements from NSTX are described in this paper.

Kumar, Deepak; Stutman, Dan; Tritz, Kevin; Finkenthal, Michael [Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218 (United States); Tarrio, Charles; Grantham, Steven [Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

2010-10-15

109

Z-Spec: a broadband millimeter-wave grating spectrometer: design, construction, and first cryogenic measurements  

Microsoft Academic Search

We present the design, integration, and first ryogenic testing of our new broad-band millimeter-wave spectrometer, Z-Spec. Z-Spec uses a novel architecture called WaFIRS (Waveguide Far-IR Spectrometer), which employs a curved diffraction grating in a parallel-plate waveguide propagation medium. The instrument will provide a resolving power betwee 200 and 350 across an instantaneous bandwidth of 190-310 GHz, all packaged within a

C. Matt Bradford; Peter A. R. Ade; James E. Aguirre; James J. Bock; Mark Dragovan; Lionel Duband; Lieko Earle; Jason Glenn; Hideo Matsuhara; Bret J. Naylor; Hien T. Nguyen; Minhee Yun; Jonas Zmuidzinas

2004-01-01

110

Liquid-helium-cooled far-infrared grating spectrometer for a balloon-borne infrared telescope  

SciTech Connect

A liquid-helium-cooled far-infrared grating spectrometer has been developed for a 50-cm balloon-borne infrared telescope. The spectral coverage is from 50 to 110 microns, with the spectral resolution of 0.5 to 0.35 micron. The diaphragm aperture is 2 arc min in diameter when attached to the telescope. This spectrometer was used in two balloon observations made in March 1985 and in August 1986 in Australia. 8 references.

Takami, H.; Maihara, T.; Mizutani, K.; Hiromoto, N.; Shibai, H.

1987-09-01

111

Study of Planck's Law with a Small USB Grating Spectrometer  

ERIC Educational Resources Information Center

In this paper an experiment to study Planck's radiation law is presented. The spectra of a heated furnace and of a halogen lamp under various conditions were measured with a small USB grating spectrometer and fitted using Planck's law. The temperature determined from the fit was then compared with the results of comparative temperature

Navratil, Zdenek; Dosoudilova, Lenka; Jurmanova, Jana

2013-01-01

112

Performance and results of the Re ection Grating Spectrometers on-board XMM-Newton  

E-print Network

Performance and results of the Re ection Grating Spectrometers on-board XMM-Newton J.W. den Herder in combination with the other instruments on-board of XMM-Newton as well as the wealth of information which, the moderate spatial resolution of the XMM-Newton telescopes requires a very high dispersion. For transmission

Audard, Marc

113

A Long Look at NGC 3783 with the XMM-Newton Reflection Grating Spectrometer  

Microsoft Academic Search

A long 280 ks observation of the Seyfert 1 galaxy NGC 3783 with XMM-Newton is reported. We focus on the oxygen line complex between 17 and 24 as measured with the Reflection Grating Spectrometer. Accurate absorption column densities and emission-line fluxes are obtained. We explore several options for the geometry and physical form of the emitting and absorbing gas.

Ehud Behar; Andrew P. Rasmussen; Alexander J. Blustin; Masao Sako; Steven M. Kahn; Jelle S. Kaastra; Graziella Branduardi-Raymont; Katrien C. Steenbrugge

2003-01-01

114

JOT JRNAL DE PHYSIQUE Colloque C 2, suppliment GU no3-4, Tome 28, mars-avril1967, page C 2 -44 A MULTIPLEX GRATING SPECTROMETER  

E-print Network

A MULTIPLEX GRATING SPECTROMETER by J. F. GRAINGER,J. RINGand J. H. STELL Department of Applied Physics interferomstre a deux ondes sont discutes. Abstract. - A near infra-red grating spectrometer for telescope use GRATING SPECTROMETER C 2 - 4 5 As is well known [2], if cp is the flux through a spec- trometer whose

Paris-Sud XI, Université de

115

Grating arrays for high--throughput soft X-ray spectrometers A. Rasmussena A. Aquilab j BookbinderC C. Chang E. Gulliksonb R. Heilmanne  

E-print Network

Grating arrays for high--throughput soft X-ray spectrometers A. Rasmussena A. Aquilab j Bookbinder keY, or 6 Angstroms. Consequently, grating spectrometers offer the current, best means by which describe grating spectrometer design candidates for the future mission Constellation--X, and how

116

In-Flight Calibration of the Chandra High Energy Transmission Grating Spectrometer  

E-print Network

We present results from in-flight calibration of the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-ray Observatory. Basic grating assembly parameters such as orientation and average grating period were measured using emission line sources. These sources were also used to determine the locations of individual CCDs within the flight detector. The line response function (LRF) was modeled in detail using an instrument simulator based on pre-flight measurements of the grating alignments and periods. These LRF predictions agree very well with in-flight observations of sources with narrow emission lines. Using bright continuum sources, we test the consistency of the detector quantum efficiencies by comparing positive orders to negative orders.

Herman L. Marshall; Daniel Dewey; Kazunori Ishibashi

2003-09-03

117

Design of a flat field concave-grating-based micro-Raman spectrometer for environmental applications.  

PubMed

In order to simplify the design process of microfabricated concave gratings, simplified algorithms for fast characterization of the concave grating were developed. These algorithms can be used to assist system designers using ray-tracing software in the determination of optimum design parameters considering the requirements and restrictions for specific applications. According to the algorithms, it is feasible to design a flat field microconcave grating with a 4 mm grating radius as a key component in a micro-Raman spectrometer system for inline environmental monitoring applications. This microspectrometer operates over the spectral wavelength band from 785 nm to 1000 nm and has a spectral resolution of 2 nm at 900 nm. The total size of the system is 1 mm4 mm3.7 mm, making it one of the smallest for this wavelength range and spectrum resolution. PMID:23033103

Li, Zhiyun; Deen, M Jamal; Fang, Qiyin; Selvaganapathy, P R

2012-10-01

118

Design of a grating spectrometer from a 1:1 Offner mirror system  

NASA Technical Reports Server (NTRS)

A 1:1 Offner mirror system is modified to work as a grating spectrometer for the infrared by placing a grating on the secondary convex mirror of the system. Slight adjustment of the configuration combined with tilt of the secondary provide the necessary degrees of freedom to correct for astigmatism of the system. Additional control may be obtained by using a holographic optical element (HOE), constructed to add necessary compensating aberrations. Details of the best configuration and the limitations of performance are presented.

Kwo, Deborah; Lawrence, George; Chrisp, Michael

1987-01-01

119

Integrated X-ray testing of the electro-optical breadboard model for the XMM reflection grating spectrometer  

SciTech Connect

X-ray calibration of the Electro-Optical Breadboard Model (EOBB) of the XXM Reflection Grating Spectrometer has been carried out at the Panter test facility in Germany. The EOBB prototype optics consisted of a four-shell grazing incidence mirror module followed by an array of eight reflection gratings. The dispersed x-rays were detected by an array of three CCDs. Line profile and efficiency measurements where made at several energies, orders, and geometric configurations for individual gratings and for the grating array as a whole. The x-ray measurements verified that the grating mounting method would meet the stringent tolerances necessary for the flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of the grating boxes fabrication. Examination of the individual grating surface`s at micron resolution revealed the cause of anomalously wide line profiles to be scattering due to the crazing of the replica`s surface.

Bixler, J.V.; Craig, W.; Decker, T. [Lawrence Livermore National Lab., CA (United States); Aarts, H.; Boggende, T. den; Brinkman, A.C. [Space Research Organization Netherlands, Utrecht (Netherlands); Burkert, W.; Brauninger, H. [Max-Planck Institute fur Extraterrestische Physik, Testanlage (Germany); Branduardi-Raymont, G. [Univ. College London (United Kingdom); Dubbeldam, L. [Space Research Organization Netherlands, Leiden (Netherlands)] [and others

1994-07-12

120

Dispersive element based on grating and tunable Fabry-Perot filter in miniature spectrometer.  

PubMed

We present a new design for the integration of a tunable Fabry-Perot (FP) filter and the grating etched on top of the cavity (IGFP) in the miniature spectrometer. It is based on the predispersion of the grating with the capacity of spatial separation of the spectral component and filter effect of the tunable FP filter. The free spectral range (FSR) of the IGFP is determined by the FSR of the grating, and its resolution depends on the filtering capacity of the FP filter. In the experiment, the high-resolution and wavelength scanning process of the IGFP were demonstrated with a narrowband and broadband light source, respectively. The results of the sub-nanometer resolution agree well with those from a commercial optical spectrum analyzer. Further, the IGFP provides an effective approach to solve the problem of the decrease of spectral resolution in the miniaturization process. PMID:24513992

Shi, Zhendong; Fang, Liang; Zhou, Chongxi

2014-01-01

121

An infrared high resolution silicon immersion grating spectrometer for airborne and space missions  

NASA Astrophysics Data System (ADS)

Broad-band infrared (IR) spectroscopy, especially at high spectral resolution, is a largely unexplored area for the far IR (FIR) and submm wavelength region due to the lack of proper grating technology to produce high resolution within the very constrained volume and weight required for space mission instruments. High resolution FIR spectroscopy is an essential tool to resolve many atomic and molecular lines to measure physical and chemical conditions and processes in the environments where galaxy, star and planets form. A silicon immersion grating (SIG), due to its over three times high dispersion over a traditional reflective grating, offers a compact and low cost design of new generation IR high resolution spectrographs for space missions. A prototype SIG high resolution spectrograph, called Florida IR Silicon immersion grating spectromeTer (FIRST), has been developed at UF and was commissioned at a 2 meter robotic telescope at Fairborn Observatory in Arizona. The SIG with 54.74 degree blaze angle, 16.1 l/mm groove density, and 50x86 mm2 grating area has produced R=50,000 in FIRST. The 1.4-1.8 um wavelength region is completely covered in a single exposure with a 2kx2k H2RG IR array. The on-sky performance meets the science requirements for ground-based high resolution spectroscopy. Further studies show that this kind of SIG spectrometer with an airborne 2m class telescope such as SOFIA can offer highly sensitive spectroscopy with R~20,000-30,000 at 20 to 55 microns. Details about the on-sky measurement performance of the FIRST prototype SIG spectrometer and its predicted performance with the SOFIA 2.4m telescope are introduced.

Ge, Jian; Zhao, Bo; Powell, Scott; Jiang, Peng; Uzakbaiuly, Berik; Tanner, David

2014-08-01

122

A Low Cost and High Capability X-ray Grating Spectrometer on the ISS  

NASA Astrophysics Data System (ADS)

We present the scientific motivation for a X-ray grating spectrometer mission to be deployed on the International Space Station. The primary goals of this mission would be to address the "missing baryon" problem, finally detecting and characterizing the Warm-Hot Intergalactic Medium that should exist as filaments threading through intergalactic space. The mission parameters are similar to those of the IXO X-ray Grating Spectrometer of R=3000 and 1000 sq. cm at 0.5 keV and a bandpass from 0.3-1.0 keV. This would also enable studies of feedback from supermassive black holes, stellar coronae, and the structure of the interstellar medium and halo of the Milky Way, amongst other goals.

Smith, Randall K.; Bookbinder, Jay A.; Brickhouse, Nancy S.; Foster, Adam; Petre, Robert; Ptak, Andrew; McEntaffer, Randall L.; Bautz, Mark W.; Burrows, David N.; Falcone, Abraham; Bregman, Joel N.; Wilms, Jrn; Willingale, Richard

2014-06-01

123

Combined optical dispersion by prism and arrayed waveguide grating with multiple diffraction orders for Raman spectrometer  

NASA Astrophysics Data System (ADS)

A compact dispersive device for Raman spectrometer was proposed to achieve a spectrum resolution below 0.55 nm in the spectral range of 800 to 1000 nm. A 41-channel arrayed waveguide grating (AWG) with eleven different diffraction orders was designed, and each output channel of this AWG contained eleven light signals with periodically 20 nm spaced wavelength. These signals were further cross-dispersed by a prism, and finally form a 41 11 spots array on a CCD. The detailed theoretical analysis and simulation of this dispersive device were introduced in this paper. Compared with commercial dispersive modules composed of grating, lens, and mirrors, the proposed structure is able to provide a compact device with higher spectrum resolution, which is attractive for handheld Raman spectrometer.

Cheng, Ya-qin; Sun, Hong-da; Wu, Zhao; Deng, Sheng-feng; Lu, Miao

2014-09-01

124

Calibration of a high resolution grating soft x-ray spectrometer  

SciTech Connect

The calibration of the soft x-ray spectral response of a large radius of curvature, high resolution grating spectrometer (HRGS) with a back-illuminated charge-coupled device detector is reported. The instrument is cross-calibrated for the 10-50 A waveband at the Lawrence Livermore National Laboratory electron beam ion trap (EBIT) x-ray source with the EBIT calorimeter spectrometer. The HRGS instrument is designed for laser-produced plasma experiments and is important for making high dynamic range measurements of line intensities, line shapes, and x-ray sources.

Magee, E. W.; Dunn, J.; Brown, G. V.; Beiersdorfer, P. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Cone, K. V.; Park, J. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States); Department of Applied Sciences, University of California, Davis, California 95616 (United States); Porter, F. S.; Kilbourne, C. A.; Kelley, R. L. [Goddard Space Flight Center, NASA, Greenbelt, Maryland 20770 (United States)

2010-10-15

125

A far-infrared Fabry-Prot interferometer and grating spectrometer for balloon-borne astronomy  

Microsoft Academic Search

A far-infrared computer-controlled Fabry-Prot interferometer has been built for use on the UCL 60 cm stabilised balloon platform for the observation of fine structure and molecular lines at moderately high spectral resolution (lambda\\/deltalambda ? 1000). The interferometer is combined with a helium cooled grating spectrometer which allows operation anywhere in the 40-115 mum wavelength range whilst minimising the thermal background

G. Poulter; R. E. Jennings

1983-01-01

126

Time-resolved x-ray transmission grating spectrometer for studying laser-produced plasmas  

Microsoft Academic Search

The development of a new time-resolved x-ray spectrometer is reported in which a free-standing x-ray transmission grating is coupled to a soft x-ray streak camera. The instrument measures continuous x-ray spectra with 20-psec temporal resolution and moderate spectral resolution (..delta..lambda> or =1 A) over a broad spectral range (0.1--5 keV) with high sensitivity and large information recording capacity. Its capabilities

N. M. Ceglio; R. L. Kauffman; A. M. Hawryluk; H. Medecki

1983-01-01

127

Calibrated Time-Resolved Transmission Grating Spectrometer for the Study of Ultrafast X-Ray Sources  

Microsoft Academic Search

A transmission grating spectrometer has been coupled to a high-temporal-resolution soft x-ray streak camera for the study of picosecond laser-plasma x-ray sources. A procedure to deconvolve the overlapping contributions of diffraction orders and to calibrate the instrument has been established in order to obtain absolute time-resolved x-ray emission spectra in the 0.11.2 keV spectral region. The deconvolution and calibration techniques

J. F. Pelletier; M. Chaker; J. C. Kieffer

1996-01-01

128

Determining ngstrm's Turbidity Coefficients: An Analysis with a Wide-Range Grating Spectrometer  

Microsoft Academic Search

The dependence of ngstrom's turbidity parameters on the wavelength has been analyzed in the wavelength interval 0.450.70 ?m. Measurements of aerosol optical thicknesses in this range were obtained by a wide-range grating spectrometer with a resolution of ? 2.5 nm. Based on such measurements, two different methods for obtaining turbidity parameters have been validated and intercompared: (a) the ratio method

V. Cuomo; F. Esposito; G. Pavese; C. Serio

1993-01-01

129

Multivariate Monte Carlo Methods for the Reflection Grating Spectrometers on XMM-Newton  

Microsoft Academic Search

We propose a novel multivariate Monte Carlo method as an efficient and\\u000aflexible approach to analyzing extended X-ray sources with the Reflection\\u000aGrating Spectrometer (RGS) on XMM Newton. A multi-dimensional interpolation\\u000amethod is used to efficiently calculate the response function for the RGS in\\u000aconjunction with an arbitrary spatially-varying spectral model. Several methods\\u000aof event comparison that effectively compare the

J. R. Peterson; J. G. Jernigan; S. M. Kahn

2004-01-01

130

XMM-Newton Reflection Grating Spectrometer Observations of the Prototypical Starburst Galaxy M82  

Microsoft Academic Search

We present results from XMM-Newton Reflection Grating Spectrometer\\u000aobservations of the prototypical starburst galaxy M82. These high resolution\\u000aspectra represent the best X-ray spectra to date of a starburst galaxy. A\\u000acomplex array of lines from species over a wide range of temperatures is seen,\\u000athe most prominent being due to Lyman-alpha emission from abundant low Z\\u000aelements such as

Andrew M. Read; Ian R. Stevens

2002-01-01

131

The high energy transmission grating spectrometer for AXAF. [Advanced X-ray Astrophysics Facility  

NASA Technical Reports Server (NTRS)

Attention is given to a high energy transmission grating spectrometer that operates over the range 0.4-8 keV, giving resolving powers of 100-1000 and effective areas of 10-200 sq cm. The instrument, which is part of the MIT high resolution X-ray spectroscopy investigation, consists of a single array of grating facets of two types: medium energy gratings of 0.6-micron period, 0.5-micron thick silver mounted behind the outer three AXAF mirrors, and high energy gratings of 0.2-micron period, 1.0-micron thick gold mounted behind the inner three mirrors. The gratings are oriented so as to correct for coma and so that the medium and high energy spectra form a shallow 'X' at the AXAF focal plane. Likely targets include normal stars, binary X-ray sources, active galactic nuclei and quasars. The HETGS can also be used to give moderate resolution spectra of slightly extended sources and monochromatic images of sources with strong lines, such as supernova remnants in nearby galaxies.

Canizares, C. R.; Schattenburg, M. L.; Smith, H. I.

1986-01-01

132

Aberration analysis of a concentric imaging spectrometer with a convex grating  

NASA Astrophysics Data System (ADS)

We analyze the ray-optical aberrations in a concentric imaging spectrometer composed of one convex grating and two concave mirrors of different radii. We assume that the system is generally not telecentric. First we derive aberration functions of Seidel and Buchdahl types for a bundle of rays converging to dispersed Gaussian images. Next we discuss the conditions in which the third and fifth-order ray aberrations are balanced. Finally we show that a concentric imaging spectrometer for use with a CCD detector can be optimized effectively in the neighborhood of a stigmatic condition. The stigmatic condition derived here can be useful in rapidly creating an initial design of a concentric imaging spectrometer with minimal aberrations.

Kim, Seo Hyun; Kong, Hong Jin; Chang, Soo

2014-12-01

133

Cost-effective optical coherence tomography spectrometer based on a tilted fiber Bragg grating  

NASA Astrophysics Data System (ADS)

A compact, fiber-based spectrometer for biomedical application utilizing a tilted fiber Bragg grating (TFBG) as integrated dispersive element is demonstrated. Based on a 45 UV-written PS750 TFBG a refractive spectrometer with 2.06 radiant/?m dispersion and a numerical aperture of 0.1 was set up and tested as integrated detector for an optical coherence tomography (OCT) system. Featuring a 23 mm long active region at the fiber the spectrum is projected via a cylindrical lens for vertical beam collimation and focused by an achromatic doublet onto the detector array. Covering 740 nm to 860 nm the spectrometer was optically connected to a broadband white light interferometer and a wide field scan head and electronically to an acquisition and control computer. Tomograms of ophthalmic and dermal samples obtained by the frequency domain OCT-system were obtained achieving 2.84 ?m axial and 7.6 ?m lateral resolution.

Remund, Stefan; Bossen, Anke; Chen, Xianfeng; Wang, Ling; Adebayo, Adedotun; Zhang, Lin; Povaay, Boris; Meier, Christoph

2014-02-01

134

Optimizing and characterizing grating efficiency for a soft X-ray emission spectrometer.  

PubMed

The efficiency of soft X-ray diffraction gratings is studied using measurements and calculations based on the differential method with the S-matrix propagation algorithm. New open-source software is introduced for efficiency modelling that accounts for arbitrary groove profiles, such as those based on atomic force microscopy (AFM) measurements; the software also exploits multi-core processors and high-performance computing resources for faster calculations. Insights from these calculations, including a new principle of optimal incidence angle, are used to design a soft X-ray emission spectrometer with high efficiency and high resolution for the REIXS beamline at the Canadian Light Source: a theoretical grating efficiency above 10% and resolving power E/?E > 2500 over the energy range from 100 eV to 1000 eV are achieved. The design also exploits an efficiency peak in the third diffraction order to provide a high-resolution mode offering E/?E > 14000 at 280 eV, and E/?E > 10000 at 710 eV, with theoretical grating efficiencies from 2% to 5%. The manufactured gratings are characterized using AFM measurements of the grooves and diffractometer measurements of the efficiency as a function of wavelength. The measured and theoretical efficiency spectra are compared, and the discrepancies are explained by accounting for real-world effects: groove geometry errors, oxidation and surface roughness. A curve-fitting process is used to invert the calculations to predict grating parameters that match the calculated and measured efficiency spectra; the predicted blaze angles are found to agree closely with the AFM estimates, and a method of characterizing grating parameters that are difficult or impossible to measure directly is suggested. PMID:23412484

Boots, Mark; Muir, David; Moewes, Alexander

2013-03-01

135

Arcus: an ISS-attached high-resolution x-ray grating spectrometer  

NASA Astrophysics Data System (ADS)

We present the design and scientific motivation for Arcus, an X-ray grating spectrometer mission to be deployed on the International Space Station. This mission will observe structure formation at and beyond the edges of clusters and galaxies, feedback from supermassive black holes, the structure of the interstellar medium and the formation and evolution of stars. The mission requirements will be R>2500 and >600 cm2 of effective area at the crucial O VII and O VIII lines, values similar to the goals of the IXO X-ray Grating Spectrometer. The full bandpass will range from 8-52 (0.25-1.5 keV), with an overall minimum resolution of 1300 and effective area >150 cm2. We will use the silicon pore optics developed at cosine Research and proposed for ESA's Athena mission, paired with off-plane gratings being developed at the University of Iowa and combined with MIT/Lincoln Labs CCDs. This mission achieves key science goals of the New Worlds, New Horizons Decadal survey while making effective use of the International Space Station (ISS).

Smith, R. K.; Ackermann, M.; Allured, R.; Bautz, M. W.; Bregman, J.; Bookbinder, J.; Burrows, D.; Brenneman, L.; Brickhouse, N.; Cheimets, P.; Carrier, A.; Freeman, M.; Kaastra, J.; McEntaffer, R.; Miller, J.; Ptak, A.; Petre, R.; Vacanti, G.

2014-07-01

136

High-Resolution X-ray Spectroscopy with a Grating Spectrometer Explorer on the ISS  

NASA Astrophysics Data System (ADS)

We present the design and scientific motivation for a X-ray grating spectrometer mission to be deployed on the International Space Station. This mission would observe the Warm-Hot Intergalactic Medium, feedback from supermassive black holes, and the structure of the interstellar medium and halo of the Milky Way, amongst other goals. The mission requirements are similar to those of the IXO X-ray Grating Spectrometer of R=3000 and 1000 cm(2) \\ of effective area at 0.5 keV, with a full bandpass covering at least between 0.3-1 keV. Our initial design baselines the silicon pore optics proposed for ESA's Athena mission with a 4.3 m focal length, paired with off-plane gratings being developed at the University of Iowa combined with MIT/Lincoln Labs CCDs. This mission would achieve core science described in the 2010 New Worlds, New Horizons Decadal survey performed by the US National Research Council while effectively using the ISS and at low cost and low risk.

Smith, Randall

137

Design of spherical varied line-space gratings for a high-resolution EUV spectrometer  

NASA Technical Reports Server (NTRS)

A highly efficient EUV spectrograph is designed for high-resolution spectroscopic observation. The spectrograph is designed for point source astronomy in a 40-120 nm bandpass and is to be ORFEUS (Orbiting Retrievable Far and Extreme Ultraviolet Spectrometer), scheduled for launch as the first payload of a German space platform Astro-SPAS (Astronomy Shuttle Pallet Satellite). The design uses spherical varied line-space (SVLS) grating to minimize astigmatism, coma, and spherical aberration. The effectiveness and practical feasibility of the design is proved by an SVLS grating for visible use. The image focusing properties of the SVLS grating for ORFEUS are compared to those with toroidal uniform line-space (TULS) design. The SVLS design is superior to the TULS, theoretically in resolution and image concentration, but also practically with not only fabrication ease. Four SVLS gratings with nominal groove densities of 6000, 4550, 3450, and 2616 gr./mm, and a 200 mm x 200 mm ruled area have been ruled using a numerically controlled ruling engine for use in ORFEUS.

Harada, Tatsuo; Kita, Toshiaki; Bowyer, Stuart; Hurwitz, Mark

1991-01-01

138

Calibration and in orbit performance of the reflection grating spectrometer onboard XMM-Newton  

E-print Network

Context: XMM-Newton was launched on 10 December 1999 and has been operational since early 2000. One of the instruments onboard XMM-Newton is the reflection grating spectrometer (RGS). Two identical RGS instruments are available, with each RGS combining a reflection grating assembly (RGA) and a camera with CCDs to record the spectra. Aims: We describe the calibration and in-orbit performance of the RGS instrument. By combining the preflight calibration with appropriate inflight calibration data including the changes in detector performance over time, we aim at profound knowledge about the accuracy in the calibration. This will be crucial for any correct scientific interpretation of spectral features for a wide variety of objects. Methods: Ground calibrations alone are not able to fully characterize the instrument. Dedicated inflight measurements and constant monitoring are essential for a full understanding of the instrument and the variations of the instrument response over time. Physical models of the instru...

de Vries, C P; Gabriel, C; Gonzalez-Riestra, R; Ibarra, A; Kaastra, J S; Pollock, A M T; Raassen, A J J; Paerels, F B S

2014-01-01

139

Calibration of a flat field soft x-ray grating spectrometer for laser produced plasmas  

SciTech Connect

We have calibrated the x-ray response of a variable line spaced grating spectrometer, known as the VSG, at the Fusion and Astrophysics Data and Diagnostic Calibration Facility at the Lawrence Livermore National Laboratory (LLNL). The VSG has been developed to diagnose laser produced plasmas, such as those created at the Jupiter Laser Facility and the National Ignition Facility at LLNL and at both the Omega and Omega EP lasers at the University of Rochester's Laboratory for Laser Energetics. The bandwidth of the VSG spans the range of {approx}6-60 A. The calibration results presented here include the VSG's dispersion and quantum efficiency. The dispersion is determined by measuring the x rays emitted from the hydrogenlike and heliumlike ions of carbon, nitrogen, oxygen, neon, and aluminum. The quantum efficiency is calibrated to an accuracy of 30% or better by normalizing the x-ray intensities recorded by the VSG to those simultaneously recorded by an x-ray microcalorimeter spectrometer.

Park, J.; Cone, K. V. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States); University of California, Davis, One Shields Avenue, Davis, California 95616 (United States); Brown, G. V.; Schneider, M. B.; Beiersdorfer, P.; Magee, E. W.; May, M. J. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States); Baldis, H. A. [University of California, Davis, One Shields Avenue, Davis, California 95616 (United States); Kelley, R. L.; Kilbourne, C. A.; Porter, F. S. [NASA Goddard Space Flight Center, Greenbelt, Maryland 20770 (United States)

2010-10-15

140

High Resolution Transmission Grating Spectrometer for Edge Toroidal Rotation Measurements of Tokamak Plasmas  

SciTech Connect

We present a high throughput (f/3) visible (3500 - 7000 Angstrom) Doppler spectrometer for toroidal rotation velocity measurements of the Alcator C-Mod tokamak plasma. The spectrometer has a temporal response of 1 ms and a rotation velocity sensitivity of {approx}10{sup 5} cm/s. This diagnostic will have a tangential view and map out the plasma rotation at several locations along the outer half of the minor radius (r/a > 0.5). The plasma rotation will be determined from the Doppler shifted wavelengths of D{sub alpha} and magnetic and electric dipole transitions of highly ionized impurities in the plasma. The fast time resolution and high spectral resolving power are possible due to a 6' diameter circular transmission grating that is capable of {lambda}/{Delta}{lambda} {approx} 15500 at 5769 Angstrom in conjunction with a 50 {micro}m slit.

Graf, A; May, M; Beiersdorfer, P; Magee, E; Lawrence, M; Terry, J; Rice, J

2004-04-29

141

Calibration of a Flat Field Soft X-ray Grating Spectrometer for Laser Produced Plasmas  

SciTech Connect

We have calibrated the x ray response of a variable line spaced grating spectrometer, known as the VSG, at the Fusion and Astrophysics Data and Diagnostic Calibration Facility at the Lawrence Livermore National Laboratory (LLNL). The VSG has been developed to diagnose laser produced plasmas, such as those created at the Jupiter Laser Facility and the National Ignition Facility at LLNL, and at both the Omega and Omega EP lasers at University of Rochester's Laboratory for Laser Energetics. The bandwidth of the VSG spans the range from {approx} 6 to 60 {angstrom}. The calibration results present here include the VSG's dispersion and quantum efficiency. The dispersion is determined by measuring the x rays emitted from hydrogen-like and helium-like ions of carbon, nitrogen, oxygen, neon, and aluminum. The quantum efficiency is calibrated to an accuracy of 30% or better by normalizing the x ray intensities recorded by the VSG to those simultaneously recorded by an x ray microcalorimeter spectrometer.

Park, J; Brown, G V; Schneider, M B; Baldis, H A; Beiersdorfer, P; Cone, K V; Kelley, R L; Kilbourne, C A; Magee, E; May, M J; Porter, F S

2010-05-12

142

[Central wavelength shift analysis between laboratory and field spectral calibrations of grating based imaging spectrometer].  

PubMed

Spectral calibration must be carried out in order to determine its central wavelength and half-wave band width of each pixel before the usage of imaging spectrometer. But it was found out that these parameters vary as environment changes. The present paper studies the effect based on test field data. The authors analyzed the optical structure and compared the working environmental parameters. Then a theoretical model is established and the influences of vibration, distortion and temperature parameters are evaluated. The theoretical model and the caculation results are in good consistency, which testifies the theoretical model. This research will shed some light on the high accuracy spectral calibration of the grating based imaging spectrometer and its manufacture. PMID:24159894

Wang, Ming-Zhi; Yan, Lei; Yang, Bin; Gou, Zhi-Yang

2013-08-01

143

High resolution transmission grating spectrometer for edge toroidal rotation measurements of tokamak plasmas  

SciTech Connect

We present a high throughput (f/3) visible (3500-7000 A) Doppler spectrometer for toroidal rotation velocity measurements of the Alcator C-Mod tokamak plasma. The spectrometer has a temporal response of 1 ms and a rotation velocity sensitivity of {approx}10{sup 5} cm/s. This diagnostic will have a tangential view and map out the plasma rotation at several locations along the outer half of the minor radius (r/a>0.5). The plasma rotation will be determined from the Doppler shifted wavelengths of D{sub {alpha}} and magnetic and electric dipole transitions of highly ionized impurities in the plasma. The fast time resolution and high spectral resolving power are possible due to a 6 in. diam circular transmission grating that is capable of {lambda}/{delta}{lambda}{approx}15 500 at 5769 A in conjunction with a 50 {mu}m slit.

Graf, A.; May, M.; Beiersdorfer, P.; Magee, E.; Lawrence, M.; Rice, J. [University of California, Davis, California 95616 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2004-10-01

144

Calibration of a flat field soft x-ray grating spectrometer for laser produced plasmasa)  

NASA Astrophysics Data System (ADS)

We have calibrated the x-ray response of a variable line spaced grating spectrometer, known as the VSG, at the Fusion and Astrophysics Data and Diagnostic Calibration Facility at the Lawrence Livermore National Laboratory (LLNL). The VSG has been developed to diagnose laser produced plasmas, such as those created at the Jupiter Laser Facility and the National Ignition Facility at LLNL and at both the Omega and Omega EP lasers at the University of Rochester's Laboratory for Laser Energetics. The bandwidth of the VSG spans the range of 6-60 . The calibration results presented here include the VSG's dispersion and quantum efficiency. The dispersion is determined by measuring the x rays emitted from the hydrogenlike and heliumlike ions of carbon, nitrogen, oxygen, neon, and aluminum. The quantum efficiency is calibrated to an accuracy of 30% or better by normalizing the x-ray intensities recorded by the VSG to those simultaneously recorded by an x-ray microcalorimeter spectrometer.

Park, J.; Brown, G. V.; Schneider, M. B.; Baldis, H. A.; Beiersdorfer, P.; Cone, K. V.; Kelley, R. L.; Kilbourne, C. A.; Magee, E. W.; May, M. J.; Porter, F. S.

2010-10-01

145

Development of silicon immersed grating for METIS on E-ELT  

NASA Astrophysics Data System (ADS)

We have developed the technology to manufacture an immersed grating in silicon for the Mid-infrared E-ELT Imager and Spectrograph, METIS. We show that we can meet the required diffraction-limited performance at a resolution of 100000 for the L and M spectral bands. Compared to a conventional grating, the immersed grating drastically reduces the beam diameter and thereby the size of the spectrometer optics. As diffraction takes place inside the high-index medium, the optical path difference and angular dispersion are boosted proportionally, thereby allowing a smaller grating area and a smaller spectrometer size. The METIS immersed grating is produced on a 150 mm industry standard for wafers and replaces a classical 400 mm echelle. Our approach provides both a feasible path for the production of a grating with high efficiency and low stray light and improves the feasibility of the surrounding spectrometer optics. In this contribution we describe and compare the classical-grating solution for the spectrometer with our novel immersed-grating based design. Furthermore, we discuss the production route for the immersed grating that is based on our long-standing experience for space-based immersed gratings. We use standard techniques from the semiconductor industry to define grating grooves with nanometer accuracy and sub-nanometer roughness. We then use optical manufacturing techniques to combine the wafer and a prism into the final immersed grating. Results of development of the critical technology steps will be discussed.

van Amerongen, Aaldert H.; Agocs, Tibor; van Brug, Hedser; Nieuwland, Govert; Venema, Lars; Hoogeveen, Ruud W. M.

2012-09-01

146

Discovery of Narrow X-Ray Absorption Lines from NGC 3783 with the Chandra High Energy Transmission Grating Spectrometer  

Microsoft Academic Search

We present the first grating-resolution X-ray spectra of the Seyfert 1 galaxy NGC 3783, obtained with the High Energy Transmission Grating Spectrometer on the Chandra X-Ray Observatory. These spectra reveal many narrow absorption lines from the H-like and He-like ions of O, Ne, Mg, Si, S, and Ar as well as Fe XVII-Fe XXI L-shell lines. We have also identified

Shai Kaspi; W. N. Brandt; Hagai Netzer; Rita Sambruna; George Chartas; Gordon P. Garmire; John A. Nousek

2000-01-01

147

Broadband FUV imaging spectrometer: advanced design with a single toroidal uniform-line-space grating.  

PubMed

Performances of a far-ultraviolet (FUV) imaging spectrometer in an advanced design are presented with a toroidal uniform-line-space (TULS) grating. It provides high spatial resolution and spectral resolution for a broadband and a wide field of view. A particular analysis for the grating aberrations, including all the high-order coefficients neglected by previous existing designs, was generated for indicating their significance. The analysis indicates that these high-order off-axis aberrations would have a remarkable influence on the design results. The transcendental equations composed of these aberration coefficients do not have analytic solutions in algebra. To solve the problem, the past designs always do some simplified calculation which only suits a narrow field of view and waveband. Thus, the optimization of the genetic algorithm is introduced to propose reasonable ranges of optical parameters. Then ZEMAX software is used to obtain the final optical system from these ranges. By comparing different design results of the same example, our advanced TULS design performs better than conventional TULS design and spherical varied-line-space grating design, and as well as the toroidal varied-line-space design. It is demonstrated that aberrations are minimized when the TULS design is operated by our method. The advanced design is low-cost, easy to fabricate, and more suitable for FUV observations. PMID:21833123

Yu, Lei; Wang, Shu-rong; Qu, Yi; Lin, Guan-yu

2011-08-01

148

[Development of spectrometer for tongue diagnosis based on plane holography concave grating].  

PubMed

The traditional tongue inspection method should be urgently improved due to the relative large diagnosis error probability caused by the excessive dependence on the Chinese physician's experience and judgment. But the application of tongue diagnosis based on image processing is limited by some factors including the performance of light source, image acquisition device and the low recognition rate of similar color for different diseases. In order to overcome these drawbacks, the spectroscopy method was employed to analyze the tongue by using the unique fingerprint effect of tongue spectrum. A spectrometer for tongue diagnosis (STD) was developed to achieve this goal in this paper. Meanwhile, to overcome the shortcomings of traditional light-splitting devices, a plane holographic concave grating was used as the diffractive grating, which not only can improve the luminous flux efficiency and miniaturize system, but also improve the spectral imaging quality and resolution. Experimental results demonstrated that the spectral range of STD reached 340-850 nm, and its spectral resolution is better than 2 nm. And the result of simulation experiment validated the feasibility of spectrometer's system. PMID:24369678

Ren, Zhong; Liu, Guo-dong; Huang, Zhen

2013-09-01

149

EGRAM- ECHELLE SPECTROGRAPH DESIGN AID  

NASA Technical Reports Server (NTRS)

EGRAM aids in the design of spectrographic systems that utilize an echelle-first order cross disperser combination. This optical combination causes a two dimensional echellogram to fall on a detector. EGRAM describes the echellogram with enough detail to allow the user to effectively judge the feasibility of the spectrograph's design. By iteratively altering system parameters, the desired echellogram can be achieved without making a physical model. EGRAM calculates system parameters which are accurate to the first order and compare favorably to results from ray tracing techniques. The spectrographic system modelled by EGRAM consists of an entrance aperture, collimator, echelle, cross dispersion grating, focusing options, and a detector. The system is assumed to be free of aberrations and the echelle, cross disperser, and detector should be planar. The EGRAM program is menu driven and has a HELP facility. The user is prompted for information such as minimum and maximum wavelengths, slit dimensions, ruling frequencies, detector geometry, and angle of incidence. EGRAM calculates the resolving power and range of order numbers covered by the echellogram. A numerical map is also produced. This tabulates the order number, slit bandpass, and high/middle/low wavelengths. EGRAM can also compute the centroid coordinates of a specific wavelength and order (or vice versa). EGRAM is written for interactive execution and is written in Microsoft BASIC A. It has been implemented on an IBM PC series computer operating under DOS. EGRAM was developed in 1985.

Dantzler, A. A.

1994-01-01

150

A liquid-helium-cooled far-infrared grating spectrometer for a balloon-borne infrared telescope  

Microsoft Academic Search

A liquid-helium-cooled far-infrared grating spectrometer has been developed for a 50-cm balloon-borne infrared telescope. The spectral coverage is from 50 mum to 110 mum, with the spectral resolution of 0.5 mum to 0.35 mum. The diaphragm aperture is 2 arc min in diameter when attached to the telescope. This spectrometer was used in two balloon observations made in March 1985

Hideki Takami; Toshinori Maihara; Kohei Mizutani; Norihisa Hiromoto; Hiroshi Shibai

1987-01-01

151

Low-energy inverse photoemission spectroscopy using a high-resolution grating spectrometer in the near ultraviolet range.  

PubMed

An inverse photoemission spectroscopy (IPES) apparatus using a Czerny-Turner grating spectrometer is demonstrated. Previous IPES instruments based on grating spectrometers used a concave grating and operated in the vacuum ultraviolet range. The reflectance of such gratings is lower than 20% and the aberration cannot be finely corrected leading to an energy resolution of up to 0.1 eV. In the present study, employing the low energy IPES regime [H. Yoshida, Chem. Phys. Lett. 539-540, 180 (2012)], incident electrons with a kinetic energy below 5 eV are used, while photon emission in the range of between 250 and 370 nm is analyzed with a 10-cm Czerny-Turner grating spectrometer. The signal intensity is at least 30 times higher than the previous apparatus. The resolution of photon detection is set at 0.07 eV though the ultimate resolution is one order of magnitude higher. The experiment is performed both by sweeping the electron energy (isochromat mode) and by simultaneously analyzing the photon of whole wavelength range (tunable photon energy mode). PMID:24182123

Yoshida, Hiroyuki

2013-10-01

152

Reflection Grating Array Associated with the Reflection Grating Spectrometer Developed by the Space Research Organization of the Netherlands for the X-ray Multi-Mirror Mission (XMM)  

NASA Technical Reports Server (NTRS)

The University of California, Berkeley (UCB) served as the Principal Investigator institution for the United States participation in the development of the Reflection Grating Spectrometer (RGS) which included the design, development, fabrication, and testing of the Reflection Grating Assembly (RGA). UCB was assisted in this role by the Lawrence Livermore National Laboratory and Columbia University who provided the primary facilities, materials, services and personnel necessary to complete the development. UC Berkeley's Dr. Steven Kahn provided the technical and scientific oversight for the design. development and testing of the RGA units by monitoring the performance of the units at various stages in their development. Dr. Kahn was also the primary contact with the Space Research Organization of the Netherlands (SRON) and represented the RGA development at all SRON and European Space Agency (ESA) reviews of the RGA status. In accordance with the contract, the team designed and developed novel optical technology to meet the unique requirements of the RGS. The ESA XMM-Newton Mission carries two identical Reflection Grating Spectrometers (RGS) behind two of its three nested sets of Wolter I type mirrors. The instrument allows high-resolution measurements in the soft X-ray range (6 to 38 angstroms or 2.1 to 0.3 keV) with a maximum effective area of about 140 sq cm at 15 angstroms. Its design is optimized for the detection of the K-shell transitions of carbon, nitrogen, oxygen, neon, magnesium, and silicon. as well as the L shell transitions of iron. The RGA itself consists of two units. A structure for each unit was designed to hold up to 220 gratings. In its final configuration, one unit holds 182 gratings and the second hold 181 gratings.

Kahn, Steven M.

2001-01-01

153

Design of a transmission grating spectrometer and an undulator beamline for soft x-ray emission studies  

SciTech Connect

A soft x-ray undulator beamline and an x-ray emission spectrometer have been designed for soft x-ray emission studies. The beamline has a varied-line-spacing plane grating monochromator, which enables the energy resolution over 104 with a beam size down to 10 x 60 {mu}m2. The x-ray emission spectrometer has a Wolter type I mirror, a free-standing transmission grating, and a back-illuminated CCD. A high collection angle up to 1.5 x 10-3 sr is achieved by utilizing the Wolter mirror as a prefocusing system. The CCD is mounted at 1400 mm downstream of the grating on a Rowland torus mount. Diffracted x-rays are detected in the normal incidence geometry, resulting in high detection efficiency. The energy resolution is limited by the figure errors of the optical elements and the spatial resolution of the detector.

Hatsui, Takaki; Kosugi, Nobuhiro [Institute for Molecular Sciences, Myodaiji, Okazaki 444-8585 (Japan); Graduate University for Advanced Studies, Myodaiji, Okazaki 444-8585 (Japan); Shigemasa, Eiji [Institute for Molecular Sciences, Myodaiji, Okazaki 444-8585 (Japan)

2004-05-12

154

CALIBRATION OF THE REFLECTION GRATING SPECTROMETERS ON-BOARD J. W. den Herder 1 , A. C. Brinkman 1 , S. M. Kahn 2 , G. Branduardi-Raymont 3 , M. Audard 4 ,  

E-print Network

1 CALIBRATION OF THE REFLECTION GRATING SPECTROMETERS ON-BOARD XMM-NEWTON J. W. den Herder 1 , A. C The Re ection Grating Spectrometers allow high-reso- lution (E/#1;E = 100 to 500) measurements of the calibration of the Re ection Grating Spectrometers will be discussed. This includes a description of the main

Guedel, Manuel

155

Multivariate Monte Carlo Methods for the Reflection Grating Spectrometers on XMM-Newton  

E-print Network

We propose a novel multivariate Monte Carlo method as an efficient and flexible approach to analyzing extended X-ray sources with the Reflection Grating Spectrometer (RGS) on XMM Newton. A multi-dimensional interpolation method is used to efficiently calculate the response function for the RGS in conjunction with an arbitrary spatially-varying spectral model. Several methods of event comparison that effectively compare the multivariate RGS data are discussed. The use of a multi-dimensional instrument Monte Carlo also creates many opportunities for the use of complex astrophysical Monte Carlo calculations in diffuse X-ray spectroscopy. The methods presented here could be generalized to other X-ray instruments as well.

J. R. Peterson; J. G. Jernigan; S. M. Kahn

2004-10-26

156

Multichannel Doppler transmission grating spectrometer at the Alcator C-Mod tokamak  

SciTech Connect

Upgrades to an existing transmission grating spectrometer for visible light used for Doppler velocity and temperature measurements at the Alcator C-Mod tokamak are given. These include a new Princeton Instruments Photonmax 512B charge-coupled device and a four channel fiber optic input. These together allow improvements to the signal level, time resolution, and the number of spatial channels. The fiber optic input allows four simultaneous spatial channels each of which offers a larger percentage of input light flux when compared to the standard fiber slit combination. The ''on chip'' amplification combined with versatile pixel binning further increases the signal to noise ratio allowing a continuous acquisition of spectra every 8 ms. The error bars for extracted velocity and temperature values are potentially smaller owing to the smaller pixel size and increased light flux which allow a more detailed line shape and simplifies line fitting. Examples of time and space resolved spectra are shown and further improvements are discussed.

Graf, A. [University of California at Davis, California 95616 (United States); May, M.; Beiersdorfer, P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2008-10-15

157

Multivariate Monte Carlo Methods for the Reflection Grating Spectrometers on XMM-Newton  

SciTech Connect

We propose a novel multivariate Monte Carlo method as an efficient and flexible approach to analyzing extended X-ray sources with the Reflection Grating Spectrometer (RGS) on XMM Newton. A multi-dimensional interpolation method is used to efficiently calculate the response function for the RGS in conjunction with an arbitrary spatially-varying spectral model. Several methods of event comparison that effectively compare the multivariate RGS data are discussed. The use of a multi-dimensional instrument Monte Carlo also creates many opportunities for the use of complex astrophysical Monte Carlo calculations in diffuse X-ray spectroscopy. The methods presented here could be generalized to other X-ray instruments as well.

Peterson, J.

2004-11-10

158

Multiwavelength campaign on Mrk 509. II. Analysis of high-quality Reflection Grating Spectrometer spectra  

E-print Network

We study the bright Seyfert 1 galaxy Mrk~509 with the Reflection Grating Spectrometers (RGS) of XMM-Newton using the RGS multi-pointing mode of XMM-Newton for the first time in order to constrain the properties of the outflow in this object. We want to obtain the most accurate spectral properties from the 600 ks spectrum of Mrk 509 which has excellent statistical quality. We derive an accurate relative calibration for the effective area of the RGS, derive an accurate absolute wavelength calibration, improve the method for adding time-dependent spectra and enhance the efficiency of the spectral fitting by two orders of magnitude. We show the major improvement of the spectral data quality due to the use of the new RGS multi-pointing mode of XMM-Newton. We illustrate the gain in accuracy by showing that with the improved wavelength calibration the two velocity troughs observed in UV spectra are resolved.

Kaastra, J S; Steenbrugge, K C; Detmers, R G; Ebrero, J; Behar, E; Bianchi, S; Costantini, E; Kriss, G A; Mehdipour, M; Paltani, S; Petrucci, P -O; Pinto, C; Ponti, G

2011-01-01

159

[A technology of real-time image compression for convex grating imaging spectrometer].  

PubMed

The huge amount of convex grating imaging spectrometer image data brings much pressure to data transmission and storage, so the image must be compressed in real time. Firstly, the image characteristics were analyzed according to the imaging principle, and the compression approach to removing spatial correlation and spectral correlation was achieved; Secondly, the compression algorithms were analyzed and the 3-D compression scheme of one-order linear compression in spectral dimension and JPEG2000 compression in spatial dimension was proposed. Finally, a real-time compression system based on FPGA and ADV212 was designed, in which FPGA was used for logic control and implementation of prediction algorithm, and ADV212 was used for JPEG2000 compression. The analysis result shows that the system has the ability of lossless and lossy compression, enabling real-time image compression. PMID:22715801

Liu, Yang-chuan; Bayanheshig; Cui, Ji-cheng; Tang, Yu-guo

2012-04-01

160

A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility.  

PubMed

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 ?m spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV. PMID:23126953

Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

2012-10-01

161

A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility  

SciTech Connect

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors it records 16 time-gated spectra between 250 and 1000 eV with 100 ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300 eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and vacuum ultraviolet beamline at the National Synchrotron Light Source, evidence a <100 {mu}m spatial resolution in combination with a source-size limited spectral resolution that is <10 eV at photon energies of 300 eV.

Moore, A. S.; Guymer, T. M.; Morton, J.; Bentley, C.; Stevenson, M. [Directorate Science and Technology, AWE Aldermaston, Reading, RG7 4PR (United Kingdom); Kline, J. L.; Taccetti, M.; Lanier, N. E.; Workman, J.; Peterson, B.; Mussack, K.; Cowan, J. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Prasad, R.; Richardson, M.; Burns, S.; Kalantar, D. H.; Benedetti, L. R.; Bell, P.; Bradley, D.; Hsing, W. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551-0808 (United States)

2012-10-15

162

A soft x-ray transmission grating imaging-spectrometer for the National Ignition Facility  

SciTech Connect

A soft x-ray transmission grating spectrometer has been designed for use on high energy-density physics experiments at the National Ignition Facility (NIF); coupled to one of the NIF gated x-ray detectors (GXD) it records sixteen time-gated spectra between 250 and 1000eV with 100ps temporal resolution. The trade-off between spectral and spatial resolution leads to an optimized design for measurement of emission around the peak of a 100-300eV blackbody spectrum. Performance qualification results from the NIF, the Trident Laser Facility and VUV beamline at the National Synchrotron Light Source (NSLS), evidence a <100{micro}m spatial resolution in combination with a source-size limited spectral resolution that is <10eV at photon energies of 300eV.

Moore, A S; Guymer, T M; Kline, J L; Morton, J; Taccetti, M; Lanier, N E; Bentley, C; Workman, J; Peterson, B; Mussack, K; Cowan, J; Prasad, R; Richardson, M; Burns, S; Kalantar, D H; Benedetti, L R; Bell, P; Bradley, D; Hsing, W; Stevenson, M

2012-05-01

163

AEGIS: An Astrophysics Experiment for Grating and Imaging Spectroscopy---a Soft X-ray, High-resolution Spectrometer  

NASA Astrophysics Data System (ADS)

AEGIS is a concept for a high-resolution soft X-ray spectroscopic observatory developed in response to NASA's request for definitions of the next X-ray astronomy mission. At a small fraction of the cost of the once-planned International X-ray Observatory (IXO), AEGIS has capabilities that surpass IXO grating spectrometer requirements, and which are far superior to those of existing soft X-ray spectrometers. AEGIS incorporates innovative technology in X-ray optics, diffraction gratings and detectors. The mirror uses high area-to-mass ratio segmented glass architecture developed for IXO, but with smaller aperture and larger graze angles optimized for high-throughput grating spectroscopy with low mass and cost. The unique Critical Angle Transmission gratings combine low mass and relaxed figure and alignment tolerances of Chandra transmission gratings but with high diffraction efficiency and resolving power of blazed reflection gratings. With more than an order of magnitude better performance over Chandra and XMM grating spectrometers, AEGIS can obtain high quality spectra of bright AGN in a few hours rather than 10 days. Such high resolving power allows detailed kinematic studies of galactic outflows, hot gas in galactic haloes, and stellar accretion flows. Absorption line spectroscopy will be used to study large scale structure, cosmic feedback, and growth of black holes in thousands of sources to great distances. AEGIS will enable powerful multi-wavelength investigations, for example with Hubble/COS in the UV to characterize the intergalactic medium. AEGIS will be the first observatory with sufficient resolution below 1 keV to resolve thermally-broadened lines in hot ( 10 MK) plasmas. Here we describe key science investigations enable by Aegis, its scientific payload and mission plan. Acknowledgements: Support was provided in part by: NASA SAO contract SV3-73016 to MIT for the Chandra X-ray Center and Science Instruments; NASA grant NNX08AI62G; and the MKI Instrumentation Development Fund.

Huenemoerder, David; Bautz, M. W.; Davis, J. E.; Heilmann, R. K.; Houck, J. C.; Marshall, H. L.; Neilsen, J.; Nicastro, F.; Nowak, M. A.; Schattenburg, M. L.; Schulz, N. S.; Smith, R. K.; Wolk, S.; AEGIS Team

2012-01-01

164

Alignment based on a no adjustment philosophy for the Immersion Grating Infrared Spectrometer (IGRINS)  

NASA Astrophysics Data System (ADS)

IGRINS, the Immersion GRating INfrared Spectrometer includes an immersion grating made of silicon and observes both H-band (1.49~1.80 ?m) and K-band (1.96~2.46 ?m), simultaneously. In order to align such an infrared optical system, the compensator in its optical components has been adjusted within tolerances at room temperature without vacuum environment. However, such a system will ultimately operate at low temperature and vacuum with no adjustment mechanism. Therefore a reasonable relationship between different environmental variations such as room and low temperature might provide useful knowledge to align the system properly. We are attempting to develop a new process to predict the Wave Front Error (WFE), and to produce correct mechanical control values when the optical system is perturbed by moving the lens at room temperature. The purpose is to provide adequate optical performance without making changes at operating temperature. In other words, WFE was measured at operating temperature without any modification but a compensator was altered correctly at room temperature to meet target performance. The `no adjustment' philosophy was achieved by deterministic mechanical adjustment at room temperature from a simulation that we developed. In this study, an achromatic doublet lens was used to substitute for the H and K band camera of IGRINS. This novel process exhibits accuracy predictability of about 0.002 ? rms WFE and can be applied to a cooled infrared optical systems.

Han, Jeong-Yeol; Yuk, In-Soo; Ko, Kyeongyeon; Oh, Heeyoung; Nah, Jakyoung; Oh, Jae Sok; Park, Chan; Lee, Sungho; Kim, Kang-Min; Chun, Moo-Young; Jaffe, Daniel T.; Pak, Soojong; Gully-Santiago, Michael

2012-12-01

165

Calibration of Xray CCDs with an ErectField Grating Spectrometer in the 0.2 1.5 keV band.  

E-print Network

Calibration of X­ray CCDs with an Erect­Field Grating Spectrometer in the 0.2 ­ 1.5 keV band. G been calibrated in the 0.25­1.5 keV spectral range using an erect­field grating spectrometer X­ray CCDs developed at MIT Lincoln Laboratories for the AXAF CCD Imaging Spectrometer (ACIS) have

166

Different approaches to precise wavelength calibration of a flat-field grating spectrometer for laser-produced plasmas  

NASA Astrophysics Data System (ADS)

Accurate mathematical models called one-line calibration and parameter fitting are presented for wavelength calibration of a flat-field grating spectrometer. The models precisely establish the relationship between wavelength and pixel position of the detector, since geometry parameters and the grating equation of the spectrometer are taken into account. Compared with the commonly used polynomial fitting, the models presented here provide more reliable calibration results, especially in the extended region away from the calibration points. In addition to the high precision of calibration, the parameter fitting procedure provides a helpful way to obtain the actual parameters of the spectrometer. Supported by the National Natural Science Foundation of China under Grant Nos 10875109, 10874156, and 11105129.

Xiong, Gang; Zhang, Jiyan; Yang, Guohong; Yang, Jiamin; Li, Hang; Hu, Zhimin; Zhao, Yang; Wei, Minxi; Yi, Tao

2014-06-01

167

Spectroscopic comparison between 1200 grooves/mm ruled and holographic gratings of a flat-field spectrometer and its absolute sensitivity calibration using bremsstrahlung continuum  

SciTech Connect

A flat-field extreme ultraviolet (EUV) spectrometer with a varied line spacing groove grating (1200 grooves/mm at grating center) has been developed to study the emission spectra from highly ionized medium Z impurities in large helical device (LHD). It covers a wavelength range of 50-500 A using a mechanically ruled grating, which was later replaced by a newly developed laminar-type holographic grating for comparative studies. Differences in spectral resolution, intensities of higher order spectra, and sensitivities of the spectrometer were studied between the two gratings by observing the emission spectra of LHD plasmas. Although the achieved resolution was alike between them, i.e., {delta}{lambda}{approx}0.24 A ring at 200 A, the holographic grating was much superior in suppressing the higher order light than the ruled grating. The relative sensitivity between the two gratings was evaluated using continuum radiation from LHD plasmas. As a result, it was found that the holographic grating has a flat response in the full wavelength range, but the sensitivity of the ruled grating drops sharply below 200 A. A new technique for the absolute calibration of the EUV holographic grating spectrometer was tried by combining the continuum radiation with a branching ratio of C IV lines (3p-3s: 5800 A/3p-2s: 312 A), and an accurate absolute sensitivity has been successfully obtained.

Chowdhuri, Malay Bikas; Morita, Shigeru; Goto, Motoshi; Nishimura, Hiroaki; Nagai, Keiji; Fujioka, Shinsuke [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292, Gifu (Japan); National Institute for Fusion Science, Toki 509-5292, Gifu (Japan); Institute of Laser Engineering, Osaka University, Suita 565-0871, Osaka (Japan)

2007-02-15

168

Direct detection submillimeter spectrometer for CCAT  

NASA Astrophysics Data System (ADS)

We present a trade study for a submillimeter direct-detection spectrometer operating at the background limit for the Cornell Caltech Atacama Telescope (CCAT). In this study we compare the classical echelle spectrometer ZEUS with the waveguide grating spectrometer Z-Spec. The science driver for this instrument is spectroscopic investigation of high redshift galaxies as their far-IR fine structure line emission is redshifted into the telluric submillimeter windows. The baseline detector consists of SQUID multiplexed TES bolometers and the ideal spectrometer to detect weak lines from distant extragalactic sources is a grating with a resolution of ~103 and a large bandwidth, covering an entire telluric submillimeter window instantaneously. Since the density of high-z sources on the sky is ~100 within a 10'10' field of view and a redshift range of ?z~0.2 we also explore multi-object (~50 objects) capability, including articulated mirrors and flexible waveguide fibers.

Nikola, Thomas; Stacey, Gordon J.; Bradford, C. Matt

2008-07-01

169

Flat-field grating spectrometer for high-resolution soft x-ray and extreme ultraviolet measurements on an electron beam ion trap  

SciTech Connect

A R=44.3 m grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for high-resolution measurements in the soft x-ray and extreme ultraviolet region spanning from below 10 up to 50 A. The instrument uses a grating with variable line spacing (about 2400 l/mm for a flat field of view. Spectra are recorded with a back-illuminated charge-coupled device detector. The new instrument greatly improves upon the resolution achieved with existing grating spectrometers and complements crystal spectrometers at the shorter wavelengths both in terms of wavelength coverage and polarization independent reflectivity response.

Beiersdorfer, P.; Magee, E.W.; Traebert, E.; Chen, H.; Lepson, J.K.; Gu, M.-F.; Schmidt, M. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); University of California, Berkeley, California 94720 (United States); Stanford University, Palo Alto, California 94305 (United States); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2004-10-01

170

Flat-field grating spectrometer for high-resolution soft x-ray and EUV measurements on an electron beam ion trap  

SciTech Connect

A R = 44.3 m grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for high-resolution measurements in the soft x-ray and extreme ultraviolet region spanning from below 10 Angstrom up to 50 Angstrom. The instrument uses a grating with variable line spacing (about 2400 l/mm) for a flat field of view. Spectra are recorded with a back-illuminated charge-coupled device detector. The new instrument greatly improves upon the resolution achieved with existing grating spectrometers and complements crystal spectrometers at the shorter wavelengths both in terms of wavelength coverage and polarization independent reflectivity response.

Beiersdorfer, P; Magee, E; Trabert, E; Chen, H; Lepson, J K; Gu, M F; Schmidt, M

2004-03-27

171

High-Resolution Observations of the Elliptical Galaxy NGC 4636 with the Reflection Grating Spectrometer on Board XMM-Newton  

Microsoft Academic Search

We present the first high spectral resolution X-ray observation of the giant elliptical galaxy NGC 4636, obtained with the reflection grating spectrometer on board the XMM-Newton Observatory. The resulting spectrum contains a wealth of emission lines from various charge states of oxygen, neon, magnesium, and iron. Examination of the cross-dispersion profiles of several of these lines provides clear, unambiguous evidence

H. Xu; S. M. Kahn; J. R. Peterson; E. Behar; F. B. S. Paerels; R. F. Mushotzky; J. G. Jernigan; A. C. Brinkman; K. Makishima

2002-01-01

172

High resolution X-ray spectroscopy of zeta Puppis with the XMM-Newton reflection grating spectrometer  

Microsoft Academic Search

We present the first high resolution X-ray spectrum of the bright O4Ief supergiant star zeta Puppis, obtained with the Reflection Grating Spectrometer on-board XMM-Newton. The spectrum exhibits bright emission lines of hydrogen-like and helium-like ions of nitrogen, oxygen, neon, magnesium, and silicon, as well as neon-like ions of iron. The lines are all significantly resolved, with characteristic velocity widths of

S. M. Kahn; M. A. Leutenegger; J. Cottam; G. Rauw; J.-M. Vreux; A. J. F. den Boggende; R. Mewe; M. Gdel

2001-01-01

173

High-Resolution X-Ray Spectra of Capella: Initial Results from the Chandra High-Energy Transmission Grating Spectrometer  

Microsoft Academic Search

High-resolution spectra of the active binary Capella (G8 III + G1 III) covering the energy range of 0.4-8.0 keV (1.5-30 ) show a large number of emission lines, demonstrating the performance of the High-Energy Transmission Grating Spectrometer. A preliminary application of plasma diagnostics provides information on coronal temperatures and densities. Lines arising from different elements in a range of ionization

C. R. Canizares; D. P. Huenemoerder; D. S. Davis; D. Dewey; K. A. Flanagan; J. Houck; T. H. Markert; H. L. Marshall; M. L. Schattenburg; N. S. Schulz; M. Wise; J. J. Drake; N. S. Brickhouse

2000-01-01

174

First Light Measurements of Capella with the Low-Energy Transmission Grating Spectrometer aboard the Chandra X-Ray Observatory  

Microsoft Academic Search

We present the first X-ray spectrum obtained by the Low-Energy Transmission Grating Spectrometer (LETGS) aboard the Chandra X-Ray Observatory. The spectrum is of Capella and covers a wavelength range of 5-175 (2.5-0.07 keV). The measured wavelength resolution, which is in good agreement with ground calibration, is Deltalambda~=0.06 (FWHM). Although in-flight calibration of the LETGS is in progress, the

A. C. Brinkman; C. J. T. Gunsing; J. S. Kaastra; R. Mewe; F. Paerels; A. J. J. Raassen; J. J. van Rooijen; H. Bruninger; W. Burkert; V. Burwitz; G. Hartner; P. Predehl; J.-U. Ness; J. H. M. M. Schmitt; J. J. Drake; O. Johnson; M. Juda; V. Kashyap; S. S. Murray; D. Pease; P. Ratzlaff; B. J. Wargelin

2000-01-01

175

XMM-Newton Reflection Grating Spectrometer Observations of Discrete Soft X-Ray Emission Features from NGC 1068  

Microsoft Academic Search

We present the first high-resolution, soft X-ray spectrum of the prototypical Seyfert 2 galaxy, NGC 1068. This spectrum was obtained with the XMM-Newton Reflection Grating Spectrometer (RGS). Emission lines from H-like and He-like low-Z ions (from C to Si) and Fe L-shell ions dominate the spectrum. Strong, narrow radiative recombination continua (RRCs) for several ions are also present, implying that

Ali Kinkhabwala; Masao Sako; Ehud Behar; Steven M. Kahn; Frits Paerels; Albert C. Brinkman; Jelle S. Kaastra; Ming Feng Gu; Duane A. Liedahl

2002-01-01

176

Absolute measurement of the spectral and angular properties of undulator radiation with a pinhole transmission grating spectrometer  

Microsoft Academic Search

Absolute measurements of undulator radiation in the soft x-ray region from 50 to 500 eV are presented. A dedicated compact pinhole transmission grating spectrometer has been built, which was calibrated with relative uncertainties between 5% (at 100 eV) and 20% (at 500 eV) in the calculable undispersed dipole radiation of the storage ring BESSY. We report measurements of the spectral

Karl Molter; Gerhard Ulm

1992-01-01

177

Fifteen years of experience with the Reflection Grating Spectrometer on XMM-Newton  

NASA Astrophysics Data System (ADS)

The RGS instrument is the X-ray spectrometer on board the XMM-Newton satellite, launched December 1999, and still fully operational. It consists of a reflection grating to disperse the incoming X-rays and a CCD camera as detector. In the past fifteen years a lot of experience has been gained in operating and calibrating this instrument. In this presentation we report on the calibration methods and status, new instrumental modes and detector performance, which were acquired and developed based on the in-flight experiences with the instrument. Selecting the proper operating modes, combined with careful data processing based on target characteristics and science goals, allows detection of weak spectral features, despite slowly degrading detectors due to radiation damage and contamination. At present the instrument has excellent health status and performance, and will be one of the few major instruments for X-ray spectroscopy in the coming years, until supplemented by new missions like ASTRO-H and, in particular, Athena.

de Vries, C. P.; den Herder, J. W.; Gonzalez-Riestra, R.; Gabriel, C.; Kaastra, J. S.; Raassen, A. J. J.; Paerels, F. B. S.; Pollock, A. M. T.; Ibarra, I.

2014-07-01

178

XMM-Newton Reflection Grating Spectrometer Observations of the Prototypical Starburst Galaxy M82  

E-print Network

We present results from XMM-Newton Reflection Grating Spectrometer observations of the prototypical starburst galaxy M82. These high resolution spectra represent the best X-ray spectra to date of a starburst galaxy. A complex array of lines from species over a wide range of temperatures is seen, the most prominent being due to Lyman-alpha emission from abundant low Z elements such as N, O, Ne, Mg and Si. Emission lines from Helium-like charge states of the same elements are also seen in emission, as are strong lines from the entire Fe-L series. Further, the OVII line complex is resolved and is seen to be consistent with gas in collisional ionization equilibrium. Spectral fitting indicates emission from a large mass of gas with a differential emission measure over a range of temperatures (from 0.2 keV to 1.6 keV, peaking at 0.7 keV), and evidence for super-solar abundances of several elements is indicated. Spatial analysis of the data indicates that low energy emission is more extended to the south and east of the nucleus than to the north and west. Higher energy emission is far more centrally concentrated.

Andrew M. Read; Ian R. Stevens

2002-06-12

179

The Upgraded Fiber Optic Echelle Spectrograph  

NASA Astrophysics Data System (ADS)

The Upgraded Fiber Optic Echelle (UFOE) is a fiber-fed, white pupil echelle spectrograph to be implemented at the Hobby-Eberly Telescope (HET) in the spring of 1997. It will serve as the commissioning spectrograph until HET facility instruments come on line in early 1998. This instrument is a quick, cost effective upgrade of the Fiber Optic Echelle, resident at KPNO for a decade. The UFOE will be capable of R = 13,900 (Nyquist limited 2 pixels/resel), with complete spectral coverage from 530 nm to 850 nm and about 90% coverage to 900 nm with adequate order separation. It utilizes a 2.5 meter radius 400 mm diameter spherical mirror to reimage an ``average'' pupil between the echelle and the cross-dispersing grating onto the entrance pupil of a 200 mm f/2 camera lens. Due to the reduction of vignetting made possible with the pupil mirror, it is estimated that the UFOE will have an efficiency of 13% on the sky when used on the HET, whereas the FOE had an efficiency of 8%. This efficiency, combined with the 9 meter aperture of the HET, should allow a limiting magnitude of V = 18.9 for a 3000 second exposure with S/N = 30 per 1/2 resel. This spectrograph has been designed and constructed at Penn State and we present results of characterization of image quality, vignetting, and focal plane characteristics.

Harlow, J. J. B.; Ramsey, L. W.; Andersen, D. R.; Fleig, J. D.; Rhoads, B. T.; Engel, L. G.

1996-12-01

180

High Resolution Soft X-ray Spectroscopy of M87 with the Reflection Grating Spectrometers on XMM-Newton  

Microsoft Academic Search

We present high-resolution X-ray spectroscopic observations of M87 with the\\u000aReflection Grating Spectrometers on XMM-Newton. We detect strong K-shell line\\u000aemission from N, O, Ne, Mg, some emission from He-like Si, a fully resolved set\\u000aof Fe L-shell emission spectra, and some emission from C. The angular intensity\\u000adistributions of the strong emission lines are detectably resolved on scales\\u000a(15-160)

I. Sakelliou; J. R. Peterson; T. Tamura; F. B. S. Paerels; J. S. Kaastra; E. Belsole; H. Boehringer; G. Branduardi-Raymont; C. Ferrigno; J. W. den Herder; J. Kennea; R. F. Mushotzky; W. T. Vestrand; D. M. Worrall

2002-01-01

181

A reflection grating spectrometer for the X-ray Multi-Mirror (XMM) space observatory - Design and calculated performance  

NASA Technical Reports Server (NTRS)

Attention is given to a spectrometer design candidate for the X-ray Multi-Mirror observatory, being planned by the European Space Agency as a long-lived large-area array of telescopes. The science requirement of moderate resolution spectroscopy in a two octave region with extremely high throughput leads to the use of grazing incidence reflection gratings. It is noted that the sensitivity of the instrument is sufficient to permit the first spectral detection of soft X-ray features in external galaxies.

Hettrick, Michael C.; Kahn, Steven M.

1986-01-01

182

Probing star formation at low and high redshift with ZEUS, a new submillimeter grating spectrometer  

NASA Astrophysics Data System (ADS)

We have detected emission in the J = 6 [arrow right] 5 transition (l = 453 mm) of the carbon monoxide isotopologue 13 CO from the starburst nucleus of the nearby galaxy NGC 253. This is the first extragalactic detection of this transition, which traces the warm, dense molecular gas found in regions of massive star formation. An excitation analysis of the CO line strengths measured here and obtained from the literature finds that [approximate] 35%-60% of the molecular gas mass ([Special characters omitted.] [approximate] 2.9 10^7 [Special characters omitted.] ) in the nuclear region is both warm ( T ~ 110 K) and dense ([Special characters omitted.] ~ 10 4 cm -3 ). We find that the gas is most likely heated either by an elevated density of cosmic rays, or by the dissipation of supersonic turbulence. As both of these heat sources are the result of stellar feedback within the starburst, our analysis suggests that the starburst may be self-limiting. We also present the detection of emission in the 2 P 3/2 [arrow right] 2 P 1/ 2 transition (l = 158 mm) of ionized carbon from MIPS J142824.0+352619, an extremely luminous star-forming galaxy at z = 1.325. We combine this measurement with existing observations of the far-infrared continuum and CO emission to estimate that the bulk of the molecular gas in this galaxy is dense ([Special characters omitted.] ~ 10 4 cm -3 ), and is illuminated by an ambient far-ultraviolet radiation field ~ 1000 times more intense than the mean field measured in our Galaxy. These are similar conditions as experienced by the molecular gas in the starburst nuclei of nearby galaxies, and suggests that this source may be modeled as a scaled-up version of a starburst nucleus. The large star formation rate and molecular gas reservoir indicate that MIPS J142824.0+352619 is likely the progenitor of one of the population of massive elliptical galaxies seen in the local Universe. These observations were made with ZEUS, a new direct-detection grating spectrometer operating at the Caltech Submillimeter Observatory. ZEUS is a broad-band spectrometer providing a resolving power of l/Dl ~ 1000 across the 350 mm and 450 mm telluric windows. It uses a 1 32 semiconductor bolometer array oriented along the dispersion direction, and is configured to simultaneously provide a 16 pixel spectrum covering Dn ~ 10 GHz in each of the two windows. The current sensitivity is within a factor of [approximate] 1.2 and [approximate] 1.3 of the background photon limit at the centers of the 350 mm and 450 mm bands, respectively, and this superb sensitivity coupled with the large instantaneous bandwidth make ZEUS an excellent tool for the observation of extragalactic spectral lines. Here we describe the design, construction, characterization, and implementation of this new instrument.

Hailey-Dunsheath, Steven

2009-06-01

183

Spectrometer Based on a VLS Grating for Diagnostics of a Vacuum-Ultraviolet Free Electron Laser  

SciTech Connect

Photon beam diagnostics for vacuum-ultraviolet free electron lasers (VUV FEL) are critical to monitoring and understanding their performance characteristics. Due to the shot-to-shot fluctuations inherent in FELs based on the self amplified spontaneous emission (SASE) process, it is mandatory to use pulse-resolved diagnostics. We have designed a spectrograph based on a variable-line-spacing (VLS) plane grating and a phosphor/CCD to monitor single shot spectra of the free electron laser at DESY. The basic concept is to allow most of the beam to be reflected towards an experimental station while the first order light is dispersed and focused by the VLS grating onto the CCD. The spectrograph will cover the wavelength range 6.4-60 nm with the CCD accepting a bandwidth of {approx}10%. The grazing angle of incidence on the grating is 2 deg., the central line density is 1200 l/mm, and the distance grating-CCD is approximately 2 m. The linear variation of the grating line spacing combined with positioning the detector at the focal curve, allows zeroing the defocus in the full spectrograph wavelength range. The correction of higher order grating aberrations yields a theoretical resolving power greater than 20000 over the full length of the 20 mm CCD when the CCD is positioned tangent to the focal plane. Based on power considerations, a shallow blazed grating is the preferred profile. Efficiency calculations over the spectrograph range show that with a carbon coating the absolute efficiency for zeroth order is higher than 0.85 and the first order efficiency varies between 0.5% and 8%.

Reininger, R. [Scientific Answers and Solutions, 5708 Restal St., Madison, WI (United States); Feldhaus, J.; Ploenjes, E.; Treusch, R. [Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, D- 22607 Hamburg (Germany); Roper, M.D.; Quinn, F.M.; Bowler, M.A. [CLRC Daresbury Laboratory, Warrington, WA4 4AD (United Kingdom)

2004-05-12

184

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facilitya)  

NASA Astrophysics Data System (ADS)

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ?E/?E? 50. It has been used at the LULI-2000 laser facility at cole Polytechnique (France) to measure the ?n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

Reverdin, Charles; Thais, Frdric; Loisel, Guillaume; Busquet, M.; Bastiani-Ceccotti, S.; Blenski, T.; Caillaud, T.; Ducret, J. E.; Foelsner, W.; Gilles, D.; Gilleron, F.; Pain, J. C.; Poirier, M.; Serres, F.; Silvert, V.; Soullie, G.; Turck-Chieze, S.; Villette, B.

2012-10-01

185

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility.  

PubMed

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ? 50. It has been used at the LULI-2000 laser facility at E?cole Polytechnique (France) to measure the ?n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented. PMID:23126955

Reverdin, Charles; Thais, Frdric; Loisel, Guillaume; Busquet, M; Bastiani-Ceccotti, S; Blenski, T; Caillaud, T; Ducret, J E; Foelsner, W; Gilles, D; Gilleron, F; Pain, J C; Poirier, M; Serres, F; Silvert, V; Soullie, G; Turck-Chieze, S; Villette, B

2012-10-01

186

X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility  

SciTech Connect

An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution {approx} 50. It has been used at the LULI-2000 laser facility at Ecole Polytechnique (France) to measure the {Delta}n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

Reverdin, Charles; Caillaud, T.; Gilleron, F.; Pain, J. C.; Silvert, V.; Soullie, G.; Villette, B. [CEA, DAM, DIF, 91297 Arpajon (France); Thais, Frederic; Loisel, Guillaume; Blenski, T.; Poirier, M. [CEA, DSM, IRAMIS, Service Photons, Atomes et Molecules, 91191 Gif-sur-Yvette (France); Busquet, M. [ARTEP Inc, Ellicott City, Maryland 21042 (United States); Bastiani-Ceccotti, S.; Serres, F. [LULI, Ecole Polytechnique, CNRS, CEA, UPMC, route de Saclay, 91128 Palaiseau (France); Ducret, J. E. [CELIA, UMR5107, CEA, CNRS, Universite de Bordeaux, 33400 Talence (France); Foelsner, W. [Max Planck Instituet fuer Quantum Optik, 85748 Garching (Germany); Gilles, D.; Turck-Chieze, S. [CEA, DSM, IRFU, Service d'astrophysique, 91191 Gif-sur-Yvette (France)

2012-10-15

187

Measurement of spatial modes of broad-area diode lasers with 1GHz resolution grating spectrometer  

Microsoft Academic Search

A 1-GHz resolution double-pass grating spectroscopy of broad-area diode lasers is performed. Measurements of spatial and spectral distribution of emitting power are performed as a function of pumping current. Results are confronted with the mode structure of gain-guided waveguide. Nonlinear coupling of lateral modes has been observed and quantified

Nikolai Stelmakh; Max Flowers

2006-01-01

188

Silicon-on-insulator spectrometers with integrated GaInAsSb photodiodes for wide-band spectroscopy from 1510 to 2300 nm.  

PubMed

We present a silicon-on-insulator (SOI) based spectrometer platform for a wide operational wavelength range. Both planar concave grating (PCG, also known as echelle grating) and arrayed waveguide grating (AWG) spectrometer designs are explored for operation in the short-wave infrared. In addition, a total of four planar concave gratings are designed to cover parts of the wavelength range from 1510 to 2300 nm. These passive wavelength demultiplexers are combined with GaInAsSb photodiodes. These photodiodes are heterogeneously integrated on SOI with benzocyclobutene (DVS-BCB) as an adhesive bonding layer. The uniformity of the photodiode characteristics and high processing yield, indicate a robust fabrication process. We demonstrate good performance of the miniature spectrometers over all operational wavelengths which paves the way to on-chip absorption spectroscopy in this wavelength range. PMID:23482178

Ryckeboer, E; Gassenq, A; Muneeb, M; Hattasan, N; Pathak, S; Cerutti, L; Rodriguez, J B; Tourni, E; Bogaerts, W; Baets, R; Roelkens, G

2013-03-11

189

A simple miniature optical spectrometer with a planar waveguide grating coupler in  

E-print Network

of Electrical and Computer Engineering, Wayne State University, Detroit, MI-48202. kalyani@wayne.edu Abstract.D. Mansell, D.A.B. Miller and J.S. Harris Jr., " Standing-wave transform spectrometer based on integrated

Avrutsky, Ivan

190

Echelle Data Reduction Cookbook  

NASA Astrophysics Data System (ADS)

This document is the first version of the Starlink Echelle Data Reduction Cookbook. It contains scripts and procedures developed by regular or heavy users of the existing software packages. These scripts are generally of two types; templates which readers may be able to modify to suit their particular needs and utilities which carry out a particular common task and can probably be used `off-the-shelf'. In the nature of this subject the recipes given are quite strongly tied to the software packages, rather than being science-data led. The major part of this document is divided into two sections dealing with scripts to be used with IRAF and with Starlink software (SUN/1).

Clayton, Martin

191

Optical Transfer Function of Concave Grating Spectrometer Based on Wave Optical Method  

Microsoft Academic Search

Optical transfer functions (OTF) of two types of spectrometer --- Eagle mounting and Seya-Namioka mounting --- are calculated by the wave-optical method which defines the OTF as the autocorrelation function of the pupil. Results obtained are compared with previous results of the present authors and interpreted as effects of diffraction and aberration on the broadening of point image. The OTFs

Tsuneo Katayama; Akio Takahashi

1970-01-01

192

Fully Automated Imaging Spectrometer  

E-print Network

Fully Automated Imaging Spectrometer User Manual Part Number 81092 ­ Revision 2 #12;Copyright................................................................................................................ 12 Installing the Grating)......................................................................................... 15 Installing the USB Spectrometer Utilities Software

Rubloff, Gary W.

193

Computed tomography imaging spectrometer (CTIS) with 2D reflective grating for ultraviolet to long-wave infrared detection especially useful for surveying transient events  

NASA Technical Reports Server (NTRS)

The optical system of this invention is an unique type of imaging spectrometer, i.e. an instrument that can determine the spectra of all points in a two-dimensional scene. The general type of imaging spectrometer under which this invention falls has been termed a computed-tomography imaging spectrometer (CTIS). CTIS's have the ability to perform spectral imaging of scenes containing rapidly moving objects or evolving features, hereafter referred to as transient scenes. This invention, a reflective CTIS with an unique two-dimensional reflective grating, can operate in any wavelength band from the ultraviolet through long-wave infrared. Although this spectrometer is especially useful for rapidly occurring events it is also useful for investigation of some slow moving phenomena as in the life sciences.

Wilson, Daniel W. (Inventor); Maker, Paul D. (Inventor); Muller, Richard E. (Inventor); Mouroulis, Pantazis Z. (Inventor)

2003-01-01

194

Computed Tomography Imaging Spectrometer (CTIS) with 2D Reflective Grating for Ultraviolet to Long-Wave Infrared Detection Especially Useful for Surveying Transient Events  

NASA Technical Reports Server (NTRS)

The optical system of this invention is an unique type of imaging spectrometer, i.e. an instrument that can determine the spectra of all points in a two-dimensional scene. The general type of imaging spectrometer under which this invention falls has been termed a computed-tomography imaging spectrometer (CTIS). CTIS's have the ability to perform spectral imaging of scenes containing rapidly moving objects or evolving features, hereafter referred to as transient scenes. This invention, a reflective CTIS with an unique two-dimensional reflective grating, can operate in any wavelength band from the ultraviolet through long-wave infrared. Although this spectrometer is especially useful for events it is also for investigation of some slow moving phenomena as in the life sciences.

Wilson, Daniel W. (Inventor); Maker, Paul D. (Inventor); Muller, Richard E. (Inventor); Mouroulis, Pantazis Z. (Inventor)

2003-01-01

195

High-Resolution Spectroscopy of the X-Ray-photoionized Wind in Cygnus X-3 with the Chandra High-Energy Transmission Grating Spectrometer  

Microsoft Academic Search

We present a preliminary analysis of the 1-10 keV spectrum of the massive X-ray binary Cygnus X-3, obtained with the high-energy transmission grating spectrometer on the Chandra X-Ray Observatory. The source reveals a richly detailed discrete emission spectrum, with clear signatures of photoionization-driven excitation. Among the spectroscopic novelties in the data are the first astrophysical detections of a number of

Frits Paerels; Jean Cottam; Masao Sako; Duane A. Liedahl; A. C. Brinkman; J. S. Kaastra; P. Predehl

2000-01-01

196

High resolution soft X-ray spectroscopy of the elliptical galaxy NGC 5044. Results from the reflection grating spectrometer on-board XMM-Newton  

Microsoft Academic Search

The results from an X-ray spectroscopic study of the giant elliptical galaxy NGC 5044 in the center of a galaxy group are presented. The line dominated soft X-ray spectra (mainly Fe-L and O Viii Lyalpha ) from the diffuse gas are resolved for the first time in this system with the Reflection Grating Spectrometers on-board XMM-Newton and provide a strong

T. Tamura; J. S. Kaastra; K. Makishima; I. Takahashi

2003-01-01

197

High Resolution Spectroscopy of 14 Cooling-Flow Clusters of Galaxies Using the Reflection Grating Spectrometers on XMM-Newton  

E-print Network

We present high resolution X-ray spectra of 14 cooling-flow X-ray clusters and groups obtained with the Reflection Grating Spectrometers (RGS) on XMM-Newton. The spectra exhibit line emission from a number of Fe L charge states as well as O VIII, Mg XII, Ne X, Si XIV & XIII, N VII, and C VI. All spectra show a deficit of soft X-ray lines predicted from the isobaric multi-phase spectral model as compared with morphological mass deposition rates from spatially-resolved spectroscopy with the European Photon Imaging Cameras (EPIC). We present some weak detections of plasma several times cooler than the ambient cluster temperatures. The results further suggest that either morphological mass deposition rates systematically overestimate the actual cooling rate or the emission measure of cooling-flows has a much steeper distribution than that predicted by a simple isobaric multi-phase model. We briefly discuss some modifications to the cooling-flow process.

J. R. Peterson; C. Ferrigno; J. S. Kaastra; F. B. S. Paerels; S. M. Kahn; J. G. Jernigan; J. A. M. Bleeker; T. Tamura

2002-02-05

198

First Light Measurements of Capella with the Low Energy Transmission Grating Spectrometer aboard the Chandra X-ray Observatory  

E-print Network

We present the first X-ray spectrum obtained by the Low Energy Transmission Grating Spectrometer (LETGS) aboard the Chandra X-ray Observatory. The spectrum is of Capella and covers a wavelength range of 5-175 A (2.5-0.07 keV). The measured wavelength resolution, which is in good agreement with ground calibration, is $\\Delta \\lambda \\simeq$ 0.06 A (FWHM). Although in-flight calibration of the LETGS is in progress, the high spectral resolution and unique wavelength coverage of the LETGS are well demonstrated by the results from Capella, a coronal source rich in spectral emission lines. While the primary purpose of this letter is to demonstrate the spectroscopic potential of the LETGS, we also briefly present some preliminary astrophysical results. We discuss plasma parameters derived from line ratios in narrow spectral bands, such as the electron density diagnostics of the He-like triplets of carbon, nitrogen, and oxygen, as well as resonance scattering of the strong Fe XVII line at 15.014 A.

A. C. Brinkman; C. J. T. Gunsing; J. S. Kaastra; R. L. J. van der Meer; R. Mewe; F. Paerels; A. J. J. Raassen; J. J. van Rooijen; H. Bruninger; W. Burkert; V. Burwitz; G. Hartner; P. Predehl; J. -U. Ness; J. H. M. M. Schmitt; J. J. Drake; O. Johnson; M. Juda; V. Kashyap; S. S. Murray; D. Pease; P. Ratzlaff; B. J. Wargelin

2000-01-04

199

High Resolution Observations of the Elliptical Galaxy NGC 4636 with the Reflection Grating Spectrometer On-Board XMM-Newton  

E-print Network

We present the first high spectral resolution X-ray observation of the giant elliptical galaxy NGC 4636, obtained with the Reflection Grating Spectrometer on-board the XMM-Newton Observatory. The resulting spectrum contains a wealth of emission lines from various charge states of oxygen, neon, magnesium, and iron. Examination of the cross-dispersion profiles of several of these lines provides clear, unambiguous evidence of resonance scattering by the highest oscillator strength lines, as well as a weak temperature gradient in the inner regions of the interstellar medium. We invoke a sophisticated new Monte Carlo technique which allows us to properly account for these effects in performing quantitative fits to the spectrum. Our spectral fits are not subject to many of the systematics that have plagued earlier investigations. The derived metal abundances are higher than have been inferred from prior, lower spectral resolution observations of this source (Awaki et al. 1994), but are still incompatible with conventional chemical enrichment models of elliptical galaxies. In addition, our data are incompatible with standard cooling flow models for this system - our derived upper limit to the mass deposition rate is below the predicted value by a factor of 3--5.

H. Xu; S. M. Kahn; J. R. Peterson; E. Behar; F. B. S. Paerels; R. F. Mushotzky; J. G. Jernigan; K. Makishima

2001-09-30

200

High resolution X-Ray spectroscopy of Zeta Puppis with the XMM-Newton Reflection Grating Spectrometer  

E-print Network

We present the first high resolution X-ray spectrum of the bright O4Ief supergiant star Zeta Puppis, obtained with the Reflection Grating Spectrometer on-board XMM-Newton. The spectrum exhibits bright emission lines of hydrogen-like and helium-like ions of nitrogen, oxygen, neon, magnesium, and silicon, as well as neon-like ions of iron. The lines are all significantly resolved, with characteristic velocity widths of order 1000-1500 km s^{-1}. The nitrogen lines are especially strong, and indicate that the shocked gas in the wind is mixed with CNO-burned material, as has been previously inferred for the atmosphere of this star from ultraviolet spectra. We find that the forbidden to intercombination line ratios within the helium-like triplets are anomalously low for N VI, O VII, and Ne IX. While this is sometimes indicative of high electron density, we show that in this case, it is instead caused by the intense ultraviolet radiation field of the star. We use this interpretation to derive constraints on the location of the X-ray emitting shocks within the wind that are consistent with current theoretical models for this system.

S. M. Kahn; M. A. Leutenegger; J. Cottam; G. Rauw; J. -M. Vreux; A. J. F. den Boggende; R. Mewe; M. Guedel

2000-11-01

201

High Resolution Soft X-ray Spectroscopy of M87 with the Reflection Grating Spectrometers on XMM-Newton  

E-print Network

We present high-resolution X-ray spectroscopic observations of M87 with the Reflection Grating Spectrometers on XMM-Newton. We detect strong K-shell line emission from N, O, Ne, Mg, some emission from He-like Si, a fully resolved set of Fe L-shell emission spectra, and some emission from C. The angular intensity distributions of the strong emission lines are detectably resolved on scales (15-160) arcsec. The gas in the inner arcmin of M87 has a multi-phase structure, as indicated by the similarity of the emission line profiles of Fe L shell ions with widely separated ionization potentials. The global Fe L spectrum is approximately consistent with an isothermal plasma at kT_e ~ 1.8 keV, in addition to a component with a temperature distribution appropriate to an isobaric cooling flow, but with a minimum temperature cutoff of kT_min ~ 600 eV. The behaviour of this cooling-flow component is qualitatively similar to what is seen in other cooling flow clusters. Finally, we do not find any strong evidence for a spatial variation in abundances due to resonance scattering redistribution in the inner arcminute of the core.

I. Sakelliou; J. R. Peterson; T. Tamura; F. B. S. Paerels; J. S. Kaastra; E. Belsole; H. Boehringer; G. Branduardi-Raymont; C. Ferrigno; J. W. den Herder; J. Kennea; R. F. Mushotzky; W. T. Vestrand; D. M. Worrall

2002-06-14

202

A Long Look at NGC 3783 with the XMM-Newton Reflection Grating Spectrometers  

E-print Network

A long 280 ks observation of the Seyfert 1 galaxy NGC 3783 with XMM-Newton is reported. We focus on the oxygen line complex between 17 and 24 A as measured with the RGS spectrometers. Accurate absorption column densities and emission line fluxes are obtained. We explore several options for the geometry and physical form of the emitting and absorbing gas. The lack of change in ionization in the absorber despite an increase in continuum flux during the observation restricts the high-ionization (O-K) and the low-ionization (Fe-M) gas to distances of at least 0.5 pc and 2.8 pc, respectively, away from the central source. Given the P-Cygni type profiles in the resonance spectral lines and the similar velocity widths, column densities, and ionization structure inferred separately from the emission and absorption lines, it is tempting to relate the X-ray narrow-line emitting plasma with the X-ray absorbing gas. Under this assumption, the scenario of dense clumped clouds can be ruled out. Conversely, extended ionization cones (r > 10 pc) are consistent with the observation independent of this assumption. These findings are in stark contrast with the picture of numerous clumpy (n_e > 10^9 cm^-3) clouds drawn recently from UV spectra, but it is consistent with the extended X-ray emission cones observed directly in Seyfert 2 galaxies.

Ehud Behar; Andrew P. Rasmussen; Alexander J. Blustin; Masao Sako; Steven M. Kahn; Jelle S. Kaastra; Graziella Branduardi-Raymont; Katrien C. Steenbrugge

2003-07-27

203

XMM-Newton Reflection Grating Spectrometer Observations of Discrete Soft-X-ray Emission Features from NGC 1068  

E-print Network

We present the first high-resolution, soft-X-ray spectrum of the prototypical Seyfert 2 galaxy, NGC 1068. This spectrum was obtained with the XMM-Newton Reflection Grating Spectrometer. Emission lines from H-like and He-like low-Z ions (from C to Si) and Fe-L-shell ions dominate the spectrum. Strong, narrow radiative recombination continua (RRC) for several ions are also present, implying that most of the observed soft-X-ray emission arises in low-temperature (few eV) plasma. This plasma is photoionized by the inferred nuclear continuum (obscured along our line of sight), as in the unified model of active galactic nuclei (AGN). We find excess emission (compared with pure recombination) in all resonance lines (np to 1s) up to the photoelectric edge, demonstrating the importance of photoexcitation as well. We introduce a simple model of a cone of plasma irradiated by the nuclear continuum; the line emission we observe along our line of sight perpendicular to the cone is produced through recombination/radiative cascade following photoionization and radiative decay following photoexcitation. A remarkably good fit is obtained to the H-like/He-like ionic line series, with inferred radial ionic column densities consistent with recent observations of warm absorbers in Seyfert 1 galaxies. Previous Chandra imaging revealed a large (extending out to 500 pc) ionization cone containing most of the X-ray flux, implying that the warm absorber in NGC 1068 is a large-scale outflow. To explain the ionic column densities, a broad, flat distribution in the logarithm of the ionization parameter ($\\xi=L_X/n_e r^2$) is necessary, spanning $\\log\\xi=0$--3. This suggests either radially-stratified ionization zones or the existence of a broad density distribution (spanning a few orders of magnitude) at each radius.

A. Kinkhabwala; M. Sako; E. Behar; S. M. Kahn; F. Paerels; A. C. Brinkman; J. S. Kaastra; M. F. Gu; D. A. Liedahl

2002-03-19

204

Electrically-programmable diffraction grating  

DOEpatents

An electrically-programmable diffraction grating. The programmable grating includes a substrate having a plurality of electrodes formed thereon and a moveable grating element above each of the electrodes. The grating elements are electrostatically programmable to form a diffraction grating for diffracting an incident beam of light as it is reflected from the upper surfaces of the grating elements. The programmable diffraction grating, formed by a micromachining process, has applications for optical information processing (e.g. optical correlators and computers), for multiplexing and demultiplexing a plurality of light beams of different wavelengths (e.g. for optical fiber communications), and for forming spectrometers (e.g. correlation and scanning spectrometers).

Ricco, Antonio J. (Albuquerque, NM); Butler, Michael A. (Albuquerque, NM); Sinclair, Michael B. (Albuquerque, NM); Senturia, Stephen D. (Brookline, MA)

1998-01-01

205

ECHOMOP: Echelle data reduction package  

NASA Astrophysics Data System (ADS)

ECHOMOP extracts spectra from 2-D data frames. These data can be single-order spectra or multi-order echelle spectra. A substantial degree of automation is provided, particularly in the traditionally manual functions for cosmic-ray detection and wavelength calibration; manual overrides are available. Features include robust and flexible order tracing, optimal extraction, support for variance arrays, and 2-D distortion fitting and extraction. ECHOMOP is distributed as part of the Starlink software collection (ascl:1110.012).

Mills, Dave; Webb, John; Clayton, Martin; Gray, Norman

2014-05-01

206

A radial velocity spectrometer for the Automated Planet Finder Telescope at Lick Observatory  

NASA Astrophysics Data System (ADS)

The Ken and Gloria Levy Spectrometer is being constructed at the Instrument Development Laboratory (Technical Facilities) of UCO/ Lick Observatory for use on the 2.4 meter Automated Planet Finder Telescope at Mt. Hamilton. The mechanical design of the instrument has been optimized for precision Doppler measurements. A key component of the design is the space-frame structure that contains passive thermal compensation. Determinate hexapod structures are used to mount the collimator, prism, and echelle grating. In this paper we describe the instrument mechanical design and some features that will help it detect rocky planets in the habitable zone.

Radovan, Matthew V.; Cabak, Gerald F.; Laiterman, Lee H.; Lockwood, Christopher T.; Vogt, Steven S.

2010-07-01

207

A new grating X-ray spectrometer for 2-4 keV enabling a separate observation of In-L? and Sn-L? emissions of indium tin oxide.  

PubMed

A new multilayer-coated varied line-spaced grating, JS4000, was fabricated and tested for extending the upper limit of a grating X-ray spectrometer for electron microscopy. This grating was designed for 2-3.8 keV at a grazing incidence angle of 1.35. It was revealed that this new multilayer structure enables us to take soft-X-ray emission spectra continuously from 1.5 to 4.3 keV at the same optical setting. The full-width at half maximum of Te-L(?1,2) (3.8 keV) emission peak was 27 eV. This spectrometer was applied to indium tin oxide particles and clearly resolved Sn-L(?) (3444 eV) and In-L(?1) (3487 eV) peaks, which could not be resolved by a widely used energy-dispersive X-ray spectrometer. PMID:23307948

Terauchi, Masami; Takahashi, Hideyuki; Handa, Nobuo; Murano, Takanori; Koike, Masato; Kawachi, Tetsuya; Imazono, Takashi; Hasegawa, Noboru; Koeda, Masaru; Nagano, Tetsuya; Sasai, Hiroyuki; Oue, Yuki; Yonezawa, Zeno; Kuramoto, Satoshi

2013-06-01

208

Effective area calibration of the reflection grating spectrometers of XMM-Newton. II. X-ray spectroscopy of DA white dwarfs  

E-print Network

White dwarf spectra have been widely used as a calibration source for X-ray and EUV instruments. The in-flight effective area calibration of the reflection grating spectrometers (RGS) of XMM-Newton depend upon the availability of reliable calibration sources. We investigate how well these white dwarf spectra can be used as standard candles at the lowest X-ray energies in order to gauge the absolute effective area scale of X-ray instruments. We calculate a grid of model atmospheres for Sirius B and HZ 43A, and adjust the parameters using several constraints until the ratio of the spectra of both stars agrees with the ratio as observed by the low energy transmission grating spectrometer (LETGS) of Chandra. This ratio is independent of any errors in the effective area of the LETGS. We find that we can constrain the absolute X-ray spectrum of both stars with better than 5 % accuracy. The best-fit model for both stars is close to a pure hydrogen atmosphere, and we put tight limits to the amount of helium or the th...

Kaastra, J S; Hubeny, I; Paerels, F B S

2009-01-01

209

Spectroscopic evaluation of three different gratings used for a flat-field extreme ultraviolet spectrometer to monitor {delta}n=1 transitions from medium-Z impurities in 10-30 A  

SciTech Connect

Spectral characteristics of varied line spacing 2400 grooves/mm gratings used for a flat-field extreme ultraviolet spectrometer have been evaluated to monitor {delta}n=1 (n=2-3) transitions from medium-Z impurities in 10-30 A, where many spectral lines from metallic impurities closely exist. For this purpose emission spectra of the {delta}n=1 transitions from partially L-shell-ionized Ti and Fe have been measured in large helical device. At first, a ruled and a holographic grating were utilized for the comparative study. Both gratings suppressed higher order light effectively but spectral sensitivity was much higher for the holographic grating. The ruled grating, however, attained better spectral resolution (0.083 A at 18.97 A) in the 10-100 A range compared to that (0.130 A) of the holographic grating. After that a recently developed new holographic grating with different laminar shapes and line spacings has attempted to improve the spectral resolution. As a result, it has considerably improved the spectral resolution in the 10-30 A range, i.e., {approx}0.090 A. However, it is found that the experimentally obtained spectral resolution is quit poor compared to the computationally simulated one, suggesting a technical difficulty in manufacturing exactly the varied line spacing of the holographic grating at such a short wavelength range.

Chowdhuri, Malay Bikas [Department of Fusion Science, Graduate University for Advanced studies, Toki, Gifu 509-5292 (Japan); Morita, Shigeru; Goto, Motoshi [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Sasai, Hiroyuki [Shimadzu Corporation, Kyoto 604-8511 (Japan)

2008-10-15

210

Chandra\\/High Energy Transmission Grating Spectrometer Spectroscopy of the Galactic Black Hole GX 339-4: A Relativistic Iron Emission Line and Evidence for a Seyfert-like Warm Absorber  

Microsoft Academic Search

We observed the Galactic black hole GX 339-4 with the Chandra High Energy Transmission Grating Spectrometer (HETGS) for 75 ks during the decline of its 2002-2003 outburst. The sensitivity of this observation provides an unprecedented glimpse of a Galactic black hole at about a tenth of the luminosity of the outburst peak. The continuum spectrum is well described by a

J. M. Miller; J. Raymond; A. C. Fabian; J. Homan; M. A. Nowak; R. A. D. Wijnands; M. van der Klis; T. Belloni; J. A. Tomsick; D. M. Smith; P. A. Charles; W. H. G. Lewin

2004-01-01

211

Grating spectrometer system for beam emission spectroscopy diagnostics using high-energy negative-ion-based neutral beam injection on LHD  

SciTech Connect

A beam emission spectroscopy (BES) system was developed for density gradient and fluctuation diagnostics in the Large Helical Device (LHD). In order to cover the large Doppler shift of the H{alpha} beam emission because of the high-energy negative-ion-based neutral beam atom (acceleration voltage V{sub acc}=90-170 kV) and the large motional Stark splitting due to the large vxB field (magnetic field B=3.0 T), a grating spectrometer was used instead of a conventional interference filter system. The reciprocal linear dispersion is about 2 nm/mm, which is sufficient to cover the motional Stark effect spectra using an optical fiber with a diameter of 1 mm.

Kado, S. [School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Oishi, T. [Graduate School/School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Yoshinuma, M.; Ida, K. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

2010-10-15

212

High Resolution Spectroscopy of the X-ray Photoionized Wind in Cygnus X-3 with the Chandra High Energy Transmission Grating Spectrometer  

E-print Network

We present a preliminary analysis of the 1--10 keV spectrum of the massive X-ray binary Cyg X-3, obtained with the High Energy Transmission Grating Spectrometer on the Chandra X-ray Observatory. The source reveals a richly detailed discrete emission spectrum, with clear signatures of photoionization-driven excitation. Among the spectroscopic novelties in the data are the first astrophysical detections of a number of He-like 'triplets' (Si, S, Ar) with emission line ratios characteristic of photoionization equilibrium, fully resolved narrow radiative recombination continua of Mg, Si, and S, the presence of the H-like Fe Balmer series, and a clear detection of a ~ 800 km/s large scale velocity field, as well as a ~1500 km/s FWHM Doppler broadening in the source. We briefly touch on the implications of these findings for the structure of the Wolf-Rayet wind.

Frits Paerels; Jean Cottam; Masao Sako; Duane A. Liedahl; A. C. Brinkman; R. L. J. van der Meer; J. S. Kaastra; P. Predehl

2000-02-16

213

Correction of spectral deformation by second-order diffraction overlap in a mid-infrared range grating spectrometer using a PbSe array detector  

NASA Astrophysics Data System (ADS)

Conventional diffraction gratings suffer from order overlap problems, especially for a mid-infrared optical emission spectrometer (mid-IR OES) using a detector array. Because of diffraction order overlap, ambiguous spectroscopic data are inevitably acquired. This shortcoming motivated us to devise an order-sorting method. We predicted a second-order diffraction overlap and corrected the deformation of signal measured with a mid-IR OES using an array detector. It is found that the first-order signal separated from the overlapped spectrum fit well with the intrinsic signal of incident light. We determined the system response function of a mid-IR OES and confirmed the validity of the compensation method by comparing the measured spectrum with Plancks curve of blackbody radiation at two different temperatures. In addition, for accuracy verification, the uncertainty factors that could affect the compensation procedures were carefully considered.

Lee, Wondong; Lee, Hyungwoo; Hahn, Jae W.

2014-11-01

214

High sensitivity transient infrared spectroscopy: a UV/Visible transient grating spectrometer with a heterodyne detected infrared probe.  

PubMed

We describe here a high sensitivity means of performing time resolved UV/Visible pump, infrared probe spectroscopy using optically Heterodyne Detected UV-IR Transient Gratings. The experiment design employed is simple, robust and includes a novel means of generating phase locked pulse pairs that relies on only mirrors and a beamsplitter. A signal to noise ratio increase of 24 compared with a conventional pump-probe arrangement is demonstrated. PMID:22714305

Donaldson, Paul M; Strzalka, Halina; Hamm, Peter

2012-06-01

215

The Discovery of Broad P Cygni X-ray Lines from Circinus X-1 with the Chandra High Energy Transmission Grating Spectrometer  

E-print Network

We present the first grating-resolution X-ray spectra of the X-ray binary Cir X-1, obtained with the High Energy Transmission Grating Spectrometer on Chandra. These reveal a rich set of lines from H-like and/or He-like Ne, Mg, Si, S and Fe detected with a high signal-to-noise ratio. The lines are broad (+/- 2000 km/s) and show P Cygni profiles. The absorption components of the lines extend to low velocity, and they have about the same widths and strengths as the corresponding emission components. The widths of the X-ray P Cygni lines are comparable to that of the broad component of the strong, asymmetric H-alpha line from Cir X-1, suggesting that the two phenomena may be related. We discuss outflow models and propose that the P Cygni profiles may arise in the moderate temperature (5 x 10^6 K) region of the wind from an X-ray heated accretion disk. This basic picture strengthens the idea that the accretion disk in Cir X-1 is viewed in a relatively edge-on manner, and it suggests that Cir X-1 is the X-ray binary analog of a Broad Absorption Line quasar.

W. N. Brandt; N. S. Schulz

2000-07-26

216

Fabrication and testing of a silicon immersion grating for infrared spectroscopy  

SciTech Connect

Recent advances in silicon micromachining techniques (e.g. anisotropic etching) allow the fabrication of very coarse infrared echelle gratings. When used in immersion mode, the dispersion is increased proportionally to the refractive index. This permits a very significant reduction in the overall size of a spectrometer while maintaining the same resolution. We have fabricated a right triangular prism (30{times}60{times}67 mm with a rectangular entrance face 30{times}38 mm) from silicon with a grating etched into the face of the hypotenuse. The grating covers an area of 32 mm by 64 mm and has a 97.5 PM periodicity with a blaze angle of 63.4{sup o}. The groove surfaces are very smooth with a roughness of a few manometers. Random defects in the silicon are the dominant source of grating scatter ({approx} 12% at 3.39 {mu}m). We measure a grating ghost intensity of 1.2%. The diffraction peak is quite narrow, slightly larger than the Airy disc diameter at F/12. However due to wavefront aberrations, perhaps 15--20% of the diffracted power is in the peak with the rest distributed in a diameter roughly five times the Airy disc.

Kuzmenko, P.J.; Ciarlo, D.R.; Stevens, C.G.

1994-07-25

217

Far-ultraviolet imaging spectrograph and scanning grating spectrometers for the Remote Atmospheric and Ionospheric Detection System  

Microsoft Academic Search

The Remote Atmospheric and Ionospheric Detection System (RAIDS) experiment is an optical remote sensing platform consisting of eight sensors, (spectrographs, spectrometers, and photometers) covering the wavelength range 550 to 8744 [angstrom]. RAIDS employs a mechanical scan platform to view the Earth's limb and measure line-of-sight column emission from tangent altitudes from 50 to 750 km. These measurements provide vertical profiles

Robert P. McCoy; R. R. Meier; K. D. Wolfram; J. M. Picone; S. E. Thonnard; G. G. Fritz; J. S. Morrill; D. A. Hardin; A. B. Christensen; D. C. Kayser; J. B. Pranke; P. R. Straus

1994-01-01

218

An aureole-corrected Langley-plot method developed for the calibration of HiRES grating spectrometers  

Microsoft Academic Search

Ground-based sensors for the vicarious calibration of spaceborne Earth remote-sensing spectrometers must be Sun-calibrated for measurements of direct solar irradiance spectra. The best results for Sun calibration control gives the classical refined Langley-plot analysis at high altitude clean air sites. This analysis fails in general for near sea-level measurements due to unstable atmosphere and inhomogeneous layers during a calibration phase.

J. Nieke; B. Pflug; G. Zimmermann

1999-01-01

219

Transmission grating streaked spectrometer for the diagnosis of soft x-ray emission from ultrahigh intensity laser heated targets  

SciTech Connect

A free-standing gold transmission grating with a period of 5000 A has been coupled to a soft x-ray sensitive streak camera with a limiting temporal resolution of 10 ps. The streak camera is equipped with a caesium iodide transmission photocathode and observations have been made in the 10-100 A regime. For a small source (200 {mu}m diameter) the spectral resolution is predicted to be around 2.5 A. This has been confirmed by examination of the Lyman-{alpha} line in hydrogen-like laser heated boron. A recorded linewidth of 2.44 A is demonstrated. The instrument has been used to diagnose the soft x-ray emission from a plastic (CH) foil target heated by an ultra-intense (2x10{sup 20} W cm{sup -2}) laser pulse.

Eagleton, R.T.; James, S.F. [AWE Aldermaston, Reading, Berkshire, RG7 4PR (United Kingdom)

2004-10-01

220

Broad-spectral-range synchronized flat-top arrayed-waveguide grating applied in a 225-channel cascaded spectrometer.  

PubMed

We present a new synchronized design for flattening the passband of an arrayed-waveguide grating (AWG) over a broad wavelength range of 90 nm. A wavelength-insensitive 3-dB balanced coupler is designed to be used in duplicate in a Mach-Zehnder interferometer (MZI); the phase deviation created by one of the balanced couplers is cancelled by flipping the other coupler around. This MZI is arranged in tandem with the AWG such that the output signal of the MZI is the input signal of the AWG. We demonstrate a 5-channel, 18-nm-spacing AWG with a 0.5-dB bandwidth of 12 nm over a 90-nm spectral range. A low-loss cascaded AWG system is demonstrated by using the MZI-synchronized flat-top AWG as a primary filter. PMID:23038381

Akca, B I; Doerr, C R; Sengo, G; Wrhoff, K; Pollnau, M; de Ridder, R M

2012-07-30

221

Study of keV radiation properties of Mo and Ti X-pinch plasma sources using a pinhole transmission grating spectrometer  

SciTech Connect

The properties of keV x-ray radiations from Mo and Ti X-pinch plasma sources at the current of 800 kA were investigated by a pinhole transmission grating spectrometer. The spectrometer was characterized by a high linear dispersion rate (2.9 A/mm), and from its time-integrated diffraction images, rich information about the X-pinch sources (e.g., source number, source size, and absolute spectra) could be obtained. Multiple hot spots were produced in all the Mo tests with loads made of two or four 25 mum wires with or without a shunt wire, and obvious increases both in the radiation intensity and in the source size around the spectral region of 2.6 keV were observed. In Ti X-pinch tests, a single keV x-ray burst with a source size of approx200 mum and a time duration of approx200 ps in full width at half maximum was obtained using a load made of two 50 mum wires plus a shunt wire. The intensity of x-rays decreased sharply from approx10{sup 11} photon eV{sup -1} sr{sup -1} at 1 keV to approx10{sup 8} photon eV{sup -1} sr{sup -1} at 4 keV. The energy-dependent source size in the band of 1-4 keV is less than 100 mum and seemed to shrink quickly as x-ray energy increases.

Li Jing [Institute of Fluid Physics, CAEP, Mianyang 621900 (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China); Deng Jianjun; Xie Weiping; Huang Xianbin; Yang Libing; Zhou Shaotong; Duan Shuchao; Zhang Siqun; Dan Jiakun [Institute of Fluid Physics, CAEP, Mianyang 621900 (China); Zhu Xiaoli [Key Laboratory of Nano-Fabrication and Novel Devices Integrated Technology, Institute of Microelectronics, CAS, Beijing 100029 (China)

2010-07-15

222

First light measurements with the XMM-Newton reflection grating spectrometers: Evidence for an inverse first ionisation potential effect and anomalous Ne abundance in the Coronae of HR 1099  

Microsoft Academic Search

The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton observatory in February 2000 as its first-light target. A total of 570 ks of exposure time was accumulated with the Reflection Grating Spectrometers (RGS). The integrated X-ray spectrum between 5-35 is of unprecedented quality and shows numerous features attributed to transitions of the elements C, N,

A. C. Brinkman; E. Behar; M. Gdel; M. Audard; A. J. F. den Boggende; G. Branduardi-Raymont; J. Cottam; C. Erd; J. W. den Herder; F. Jansen; J. S. Kaastra; S. M. Kahn; R. Mewe; F. B. S. Paerels; J. R. Peterson; A. P. Rasmussen; I. Sakelliou; C. de Vries

2001-01-01

223

First Light Measurements with the XMM-Newton Reflection Grating Spectrometers: Evidence for an Inverse First Ionisation Potential Effect and Anomalous Ne A bundance in the Coronae of HR 1099  

Microsoft Academic Search

The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton\\u000aobservatory in February 2000 as its first-light target. A total of 570 ks of\\u000aexposure time was accumulated with the Reflection Grating Spectrometers (RGS).\\u000aThe integrated X-ray spectrum between 5-35 Angstrom is of unprecedented quality\\u000aand shows numerous features attributed to transitions of the elements C, N,

A. C. Brinkman; E. Behar; M. Audard; A. J. F. den Boggende; G. Branduardi-Raymont; J. Cottam; C. Erd; J. W. den Herder; F. Jansen; J. S. Kaastra; S. M. Kahn; R. Mewe; F. B. S. Paerels; J. R. Peterson; A. P. Rasmussen; I. Sakelliou; C. de Vries

2000-01-01

224

High resolution soft X-ray spectroscopy of the elliptical galaxy NGC 5044. Results from the reflection grating spectrometer on-board XMM-Newton  

E-print Network

The results from an X-ray spectroscopic study of the giant elliptical galaxy NGC5044 in the center of a galaxy group are presented. The line dominated soft X-ray spectra (mainly Fe-L and O VIII Ly_a) from the diffuse gas are resolved for the first time in this system with the Reflection Grating Spectrometers on-board XMM-Newton and provide a strong constraint on the temperature structure. The spectra integrated over 2' (\\sim 20kpc) in full-width can be described by a two temperature plasma model of 0.7keV and 1.1keV. Most of the latter component is consistent with originating from off-center regions. Compared to the isobaric cooling flow prediction, the observation shows a clear cut-off below a temperature of 0.6 +-0.1keV. Furthermore, the Fe and O abundances within the central 10--20kpc in radius are accurately measured to be 0.55+-0.05 and 0.25+-0.1 times the solar ratios, respectively. The observed cut-off temperature of this galaxy and other central galaxies in galaxy groups and clusters are compared with the scale of the galaxy and properties of the surrounding intra-cluster medium. Based on this comparison, the origin of the lack of predicted cool emission is discussed.

T. Tamura; J. S. Kaastra; K. Makishima; I. Takahashi

2002-11-27

225

Effective area calibration of the Reflection Grating Spectrometers of XMM-Newton. I. X-ray spectroscopy of the Crab nebula  

E-print Network

The Crab nebula and pulsar have been widely used as a calibration source for X-ray instruments. The in-flight effective area calibration of the Reflection Grating Spectrometers (RGS) of XMM-Newton depend upon the availability of reliable calibration sources. We investigate how the absolute effective area calibration of RGS can be obtained using Crab as a standard candle. We have analysed RGS observations of the Crab using different instrument configurations and spatial offsets, and made use of previous determinations of the continuum spectrum of the nebula plus pulsar. Due to the high spectral resolution of the RGS, we resolve the main absorption edges and detect the strong 1s-2p absorption lines of neutral oxygen. We get an excellent fit to the Crab spectrum using this fixed continuum and the absorption spectrum determined by RGS. We get accurate column densities for the neutral atoms of H, N, O, Ne, Mg, and Fe, as well as a clear detection of Fe II and firm upper limits for other ions. Our data are in good ...

Kaastra, J S; Costantini, E; Herder, J W A den

2009-01-01

226

Electrically-programmable diffraction grating  

DOEpatents

An electrically-programmable diffraction grating is disclosed. The programmable grating includes a substrate having a plurality of electrodes formed thereon and a moveable grating element above each of the electrodes. The grating elements are electrostatically programmable to form a diffraction grating for diffracting an incident beam of light as it is reflected from the upper surfaces of the grating elements. The programmable diffraction grating, formed by a micromachining process, has applications for optical information processing (e.g. optical correlators and computers), for multiplexing and demultiplexing a plurality of light beams of different wavelengths (e.g. for optical fiber communications), and for forming spectrometers (e.g. correlation and scanning spectrometers). 14 figs.

Ricco, A.J.; Butler, M.A.; Sinclair, M.B.; Senturia, S.D.

1998-05-26

227

Noise analysis of spectrometers based on speckle pattern reconstruction  

E-print Network

compare the accuracy of a speckle-based spectrometer to a traditional grating-based spectrometer comparable performance to a grating-based spectrometer when measuring intense or narrowband probe signals Traditional spectrometers rely on a grating or prism to provide one-to-one spectral to spatial mapping

Cao, Hui

228

MODELING THE TRIPLET SPECTRAL REGION CAPELLA WITH THE CHANDRA AND XMMNEWTON GRATINGS  

E-print Network

Transmission Grating Spectrometer (HETGS; 155 Energy Transmission Grating Spectrometer (LETGS; 219 and Reflection Grating Spectrometer (RGS; comparative analysis, focusing triplet around 13.5 , regionMODELING THE TRIPLET SPECTRAL REGION CAPELLA WITH THE CHANDRA AND XMM­NEWTON GRATINGS Jan

Ness, Jan-Uwe

229

Development of off-plane gratings for WHIMex and IXO Randall L. McEntaffer*a  

E-print Network

-plane grating spectrometers consist of an array of gratings capable of reaching resolutions above 3000 (/). Concept designs have been made for the International X-ray Observatory X-ray Grating Spectrometer. More) baseline configuration includes an X-ray Grating Spectrometer (XGS) instrument. The purpose of the IXO XGS

230

Educational Multiwavelength Atomic Emission Spectrometer  

E-print Network

Educational Multiwavelength Atomic Emission Spectrometer Alexander Y. Nazarenko* Chemistry multiwavelength emission instrument utilizing a commercial grating monochromator, a fiber optic sensor to collect visualization makes the spectrometer a useful educational tool. Key Words: Atomic emission spectroscopy; CCD

Nazarenko, Alexander

231

CHIRON - A Fiber Fed Spectrometer for Precise Radial Velocities  

NASA Astrophysics Data System (ADS)

The CHIRON optical high-resolution echelle spectrometer was commissioned at the 1.5 m telescope at CTIO in 2011. The instrument was designed for high throughput and stability, with the goal of monitoring radial velocities of bright stars with high precision and high cadence for the discovery of low-mass exoplanets. Spectral resolution of R = 79 000 is attained when using a slicer with a total (including telescope and detector) efficiency of 6% or higher, while a resolution of R = 136 000 is available for bright stars. A fixed spectral range of 415--880 nm is covered. The echelle grating is housed in a vacuum enclosure and the instrument temperature is stabilized to 0.2. Stable illumination is provided by an octagonal multimode fiber with excellent light-scrambling properties. An iodine cell is used for wavelength calibration. We describe the main optics, fiber feed, detector, exposure-meter, and other aspects of the instrument, as well as the observing procedure and data reduction.

Tokovinin, Andrei; Fischer, Debra A.; Bonati, Marco; Giguere, Matthew J.; Moore, Peter; Schwab, Christian; Spronck, Julien F. P.; Szymkowiak, Andrew

2013-11-01

232

THE ACCRETION DISK CORONA AND DISK ATMOSPHERE OF 4U 1624-490 AS VIEWED BY THE CHANDRA-HIGH ENERGY TRANSMISSION GRATING SPECTROMETER  

SciTech Connect

We present a detailed spectral study (photoionization modeling and variability) of the 'Big Dipper' 4U 1624-490 based on a Chandra-High Energy Transmission Grating Spectrometer (HETGS) observation over the {approx}76 ks binary orbit of 4U 1624-490 . While the continuum spectrum can be modeled using a blackbody plus power law, a slightly better fit is obtained using a single {gamma} = 2.25 power-law partially (71%) covered by a local absorber of column density N{sub H,Local}=8.1{sub -0.6}{sup +0.7}x10{sup 22} cm{sup -2}. The data show a possible quasi-sinusoidal modulation with period 43{sup +13} {sub -9} ks that might be due to changes in local obscuration. Photoionization modeling with the XSTAR code and variability studies of the observed strong Fe XXV and Fe XXVI absorption lines point to a two-temperature plasma for their origin: a highly ionized component of ionization parameter {xi}{sub hot} {approx} 10{sup 4.3} erg cm s{sup -1} (T {approx} 3.0 x 10{sup 6} K) associated with an extended accretion disk corona of radius R {approx} 3 x 10{sup 10} cm, and a less-ionized more variable component of {xi} {approx} 10{sup 3.4} erg cm s{sup -1} (T {approx} 1.0 x 10{sup 6} K) and {xi}{approx}10{sup 3.1} erg cm s{sup -1} (T {approx} 0.9 x 10{sup 6} K) coincident with the accretion disk rim. We use this, with the observed Fe XXV and Fe XXVI absorption line variations (in wavelength, strength, and width) to construct a viewing geometry that is mapped to changes in plasma conditions over the 4U 1624-490 orbital period.

Xiang Jingen; Lee, Julia C. [Department of Astronomy (a part of the Harvard-Smithsonian Center for Astrophysics), Harvard University, 60 Garden Street, Cambridge, MA 02138 (United States); Nowak, Michael A.; Schulz, Norbert S. [Massachusetts Institute of Technology, Kavli Center, 77 Massachusetts Avenue NE80, Cambridge, MA 02139 (United States); Wilms, Joern [Dr. Karl-Remeis-Observatory and Erlangen Centre for Astroparticle Physics, University of Erlangen-Nuremberg, Sternwartstrasse 7, 96049 Bamberg (Germany)], E-mail: jxiang@cfa.harvard.edu, E-mail: jclee@cfa.harvard.edu

2009-08-20

233

The FIRE infrared spectrometer at Magellan: construction and commissioning  

E-print Network

We describe the construction and commissioning of FIRE, a new 0.8-2.5?m echelle spectrometer for the Magellan/ Baade 6.5 meter telescope. FIRE delivers continuous spectra over its full bandpass with nominal spectral ...

Simcoe, Robert A.

234

The assembly, calibration, and preliminary results from the Colorado high-resolution Echelle stellar spectrograph (CHESS)  

NASA Astrophysics Data System (ADS)

The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) is a far ultraviolet (FUV) rocket-borne experiment designed to study the atomic-to-molecular transitions within translucent interstellar clouds. CHESS is an objective echelle spectrograph operating at f/12.4 and resolving power of 120,000 over a band pass of 100 - 160 nm. The echelle flight grating is the product of a research and development project with LightSmyth Inc. and was coated at Goddard Space Flight Center (GSFC) with Al+LiF. It has an empirically-determined groove density of 71.67 grooves/mm. At the Center for Astrophysics and Space Astronomy (CASA) at the University of Colorado (CU), we measured the efficiencies of the peak and adjacent dispersion orders throughout the 90 - 165 nm band pass to characterize the behavior of the grating for pre-flight calibrations and to assess the scattered-light behavior. The crossdispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, low line density (351 grooves/mm), powered optic with a toroidal surface curvature. The CHESS cross-disperser was also coated at GSFC; Cr+Al+LiF was deposited to enhance far-UV efficiency. Results from final efficiency and reflectivity measurements of both optics are presented. We utilize a cross-strip anode microchannel plate (MCP) detector built by Sensor Sciences to achieve high resolution (25 ?m spatial resolution) and data collection rates (~ 106 photons/second) over a large format (40mm round, digitized to 8k x 8k) for the first time in an astronomical sounding rocket flight. The CHESS instrument was successfully launched from White Sands Missile Range on 24 May 2014. We present pre-flight sensitivity, effective area calculations, lab spectra and calibration results, and touch on first results and post-flight calibration plans.

Hoadley, Keri; France, Kevin; Nell, Nicholas; Kane, Robert; Schultz, Ted; Beasley, Matthew; Green, James; Kulow, Jen; Kersgaard, Eliot; Fleming, Brian

2014-07-01

235

MODELING THE Ne ix TRIPLET SPECTRAL REGION OF CAPELLA WITH THE CHANDRA AND XMM-NEWTON GRATINGS  

E-print Network

gathered together all available data of the High Energy Transmission Grating Spectrometer (HETGS; 155 ks), Low Energy Transmission Grating Spectrometer (LETGS; 219 ks), and Reflection Grating Spectrometer (RGSMODELING THE Ne ix TRIPLET SPECTRAL REGION OF CAPELLA WITH THE CHANDRA AND XMM-NEWTON GRATINGS Jan

Ness, Jan-Uwe

236

The ORFEUS II Echelle spectrum of HD 93521: A reference for interstellar molecular hydrogen  

NASA Astrophysics Data System (ADS)

During the second flight of the ORFEUS-SPAS mission in November/December 1996, the Echelle spectrometer was used extensively by the Principal and Guest Investigator teams as one of the two focal plane instruments of the ORFEUS telescope. The spectrum of HD 93521 was obtained during this mission with a total integration time of 1740 s. This spectrum shows numerous sharp interstellar absorption lines. We identified 198 lines of molecular hydrogen including at least 7 lines with a high velocity component. Also most of the 67 identified interstellar metal lines are visible with a high velocity component. We present plots of the complete ORFEUS II Echelle spectrum together with tables of all identified interstellar absorption lines including all 14 detectable H I lines. In addition several identified stellar lines, partially with narrow absorption components, and stellar wind lines are given in a separate table.

Barnstedt, J.; Gringel, W.; Kappelmann, N.; Grewing, M.

2000-04-01

237

Development of lightweight blazed transmission gratings and large-area soft x-ray spectrographs  

E-print Network

-ray band can only be achieved with a state-of-the-art diffraction grating spectrometer, comprised of large of higher diffraction orders). Several new mission concepts containing CAT grating based spectrometers resolving power (R = / > 3000) x-ray grating spectrometer (XGS)4,5 with more than an order of magnitude

238

Precision Shaping, Assembly and Metrology of Foil Optics for X-ray Reflection Gratings  

E-print Network

cQED Technologies, Inc., Rochester, NY 14607 ABSTRACT The proposed Reflection Grating Spectrometer spectrometer flown on the X-ray Multi-Mirror (XMM) mission. Off-plane, or conical, gratings require much higher, wavefront sensing, magneto-rheologic finishing, MRF 1. INTRODUCTION The Reflection Grating Spectrometer (RGS

239

The Constellation-X RGS options: Raytrace Modeling of the Off-plane Gratings  

E-print Network

The Reflection Grating Spectrometer of the Constellation-X mission has two strong candidate configurations-resolution spectral coverage is provided by a reflection grating spectrometer (RGS) and the X-Ray Microcalorimeter. The Reflection Grating Spectrometer (RGS) of Constellation-X provides high resolution X-ray spectra over 0

240

Off-plane gratings for Constellation-X R. McEntaffer  

E-print Network

for Astrophysics and Space Astronomy, University of Colorado ABSTRACT A reflection grating spectrometer featuring-X, Reflection Grating Spectrometer, off-plane mount, high spectral resolution 1. INTRODUCTION The Constellation ­ a calorimeter and a reflection grating spectrometer (RGS). The calorimeter is optimized for spectroscopy from 1

Cash, Webster

241

Modulated optical solid-state spectrometer applications in plasma diagnostics  

E-print Network

, and inexpensive and offers a number of advantages over conventional grating based spectrometers. Most importantly the MOSS spectrometer is an inexpensive and powerful alternative to multichannel grating spectrometersModulated optical solid-state spectrometer applications in plasma diagnostics John Howard Plasma

Howard, John

242

A planar lightwave circuit based micro interrogator and its applications to the interrogation of multiplexed optical fiber Bragg grating sensors  

Microsoft Academic Search

Optical fiber Bragg grating sensors have found potential applications in many fields, but the lack of a simple, field deployable and low cost interrogation system is hindering their deployment. To tackle this, we have developed a micro optical sensor interrogator using a monolithically integrated planar lightwave circuit based echelle diffractive grating demultiplexer and a detector array. The design and development

Gaozhi Xiao; Nezih Mrad; Honglei Guo; Zhiyi Zhang; Jianping Yao

2008-01-01

243

Electromagnetic diffraction efficiencies for plane reflection diffraction gratings  

NASA Technical Reports Server (NTRS)

The theory and computer programs, based on electromagnetic theory, for the analysis and design of echelle gratings were developed. The gratings are designed for instruments that operate in the ultraviolet portion of the spectrum. The theory was developed so that the resulting computer programs will be able to analyze deep (up to 30 wavelengths) gratings by including as many as 100 real or homogeneous diffraction orders. The program calculates the complex amplitude coefficient for each of the diffracted orders. A check on the numerical method used to solve the integral equations is provided by a conservation of energy calculation.

Marathay, A. S.; Shrode, T. E.

1974-01-01

244

First Light Measurements with the XMM-Newton Reflection Grating Spectrometers: Evidence for an Inverse First Ionization Potential Effect and Anomalous Ne Abundance in the Coronae of HR 1099  

NASA Technical Reports Server (NTRS)

The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton observatory in February 2000 as its first-light target. A total of 570 ks of exposure time was accumulated with the Reflection Grating Spectrometers (RGS). The integrated X-ray spectrum between 5-38A is of unprecedented quality and shows numerous features attributed to transitions of the elements C, N, O, Ne, Mg, Si, S, Fe. Ni, and probably others. We perform an in-depth study of the elemental composition of the average corona of this system, and find that the elemental abundances strongly depend on the first ionisation potential (FIP) of the elements. But different from the solar coronal case, we find an inverse FIP effect, i.e., the abundances (relative to oxygen) increase with increasing FIP. Possible scenarios, e.g., selective enrichment due to Ne-rich flare-like events, are discussed.

Brinkman, A. C.; Behar, E.; Guedel, M.; Audard, M.; denBoggende, A. J. F.; Branduardi-Raymont, G.; Cottam, J.; Erd, C.; denHerder, J. W.; Jensen, F.

2000-01-01

245

First Light Measurements with the XMM-Newton Reflection Grating Spectrometers: Evidence for an Inverse First Ionisation Potential Effect and Anomalous Ne A bundance in the Coronae of HR 1099  

E-print Network

The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton observatory in February 2000 as its first-light target. A total of 570 ks of exposure time was accumulated with the Reflection Grating Spectrometers (RGS). The integrated X-ray spectrum between 5-35 Angstrom is of unprecedented quality and shows numerous features attributed to transitions of the elements C, N, O, Ne, Mg, Si, S, Fe, and Ni. We perform an in-depth study of the elemental composition of the average corona of this system, and find that the elemental abundances strongly depend on the first ionisation potential (FIP) of the elements. But different from the solar coronal case, we find an inverse FIP effect, i.e., the abundances (relative to oxygen) increase with increasing FIP. Possible scenarios, e.g., selective enrichment due to Ne-rich flare-like events, are discussed.

A. C. Brinkman; E. Behar; M. Guedel; M. Audard; A. J. F. den Boggende; G. Branduardi-Raymont; J. Cottam; C. Erd; J. W. den Herder; F. Jansen; J. S. Kaastra; S. M. Kahn; R. Mewe; F. B. S. Paerels; J. R. Peterson; A. P. Rasmussen; I. Sakelliou; C. de Vries

2000-11-01

246

A soft X-ray study of type I active galactic nuclei observed with Chandra high-energy transmission grating spectrometer  

Microsoft Academic Search

We present the results of a uniform analysis of the soft X-ray spectra of 15 type I active galactic nuclei (AGN) observed with the high-resolution X-ray gratings onboard Chandra. We found that 10 out of the 15 AGN exhibit signatures of an intrinsic ionized absorber. The absorbers are photoionized and outflowing, with velocities in the range ~101 - 103 km

B. McKernan; T. Yaqoob; C. S. Reynolds

2007-01-01

247

WAVELENGTH CALIBRATION OF THE HAMILTON ECHELLE SPECTROGRAPH  

SciTech Connect

We present the wavelength calibration of the Hamilton Echelle Spectrograph at Lick Observatory. The main problem with the calibration of this spectrograph arises from the fact that thorium lines are absent in the spectrum of the presumed ThAr hollow-cathode lamp now under operation; numerous unknown strong lines, which have been identified as titanium lines, are present in the spectrum. We estimate the temperature of the lamp's gas which permits us to calculate the intensities of the lines and to select a large number of relevant Ti I and Ti II lines. The resulting titanium line list for the Lick hollow-cathode lamp is presented. The wavelength calibration using this line list was made with an accuracy of about 0.006 .

Pakhomov, Yu. V. [Institute of Astronomy, Russian Academy of Sciences, Moscow (Russian Federation); Zhao, G., E-mail: pakhomov@inasan.ru [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2013-10-01

248

NRES: the network of robotic Echelle spectrographs  

NASA Astrophysics Data System (ADS)

Las Cumbres Observatory Global Network (LCOGT) is building the Network of Robotic Echelle Spectrographs (NRES), which will consist of six identical, optical (390 - 860 nm) high-precision spectrographs, each fiber-fed simultaneously by two 1 meter telescopes and a thorium argon calibration source, one at each of our observatory sites in the Northern and Southern hemispheres. Thus, NRES will be a single, globally-distributed, autonomous observing facility using twelve 1-m telescopes. Simulations suggest we will achieve long-term precision of better than 3 m/s in less than an hour for stars brighter than V = 12. We have been fully funded with an NSF MRI grant, and expect our first spectrograph to be deployed in Spring of 2015, with the full network operation of all 6 units beginning in Spring of 2016. We discuss the NRES design, goals, and robotic operation, as well as the early results from our prototype spectrograph.

Eastman, Jason D.; Brown, Timothy M.; Hygelund, John; van Eyken, Julian; Tufts, Joseph R.; Barnes, Stuart

2014-07-01

249

Engineering of the passband function of a generalized spectrometer  

E-print Network

engineering of a grating spectrometer. Through spatial masking of the input beam and translation of diffraction grating-based spectrometers [1], surprising new be- havior is found to arise in even the simplestEngineering of the passband function of a generalized spectrometer J.D. McKinney and A.M. Weiner

Purdue University

250

Efficiency of a grazing-incidence off-plane grating in the soft-x-ray region  

E-print Network

- Newton Reflection Grating Spectrometer and Chan- dra. Off-plane grating efficiencies were first measuredEfficiency of a grazing-incidence off-plane grating in the soft-x-ray region J. F. Seely, L. I-incidence diffraction grating in the off-plane mount were performed using polarized synchrotron radiation. The grating

251

Modeling the Chandra High Energy Transmission Gratings below 2 keV  

E-print Network

The High Energy Transmission Grating Spectrometer of the Chandra X-Ray Observatory is a high spectral The High Energy Transmission Grating Spectrometer (HETGS) of the Chandra X-Ray Observatory is a highModeling the Chandra High Energy Transmission Gratings below 2 keV K.A. Flanagana, T.H. Markerta, J

252

Off-plane grating mount tolerances for Constellation-X Webster Cash and Ann Shipley  

E-print Network

-plane approach to the Reflection Grating Spectrometer of the Constellation-X Mission. In this paper we discuss two instruments ­ a calorimeter and a reflection grating spectrometer (RGS). The calorimeterOff-plane grating mount tolerances for Constellation-X Webster Cash and Ann Shipley University

Cash, Webster

253

Color Perception with Diffraction Gratings.  

ERIC Educational Resources Information Center

Describes an experiment enabling students to apply concept of diffraction, determine limits of their color perception, learn how to measure wavelength with a simple apparatus, observe continuous and line spectra, and associate colors with corresponding wavelengths. The homemade diffraction-grating spectrometer used is easily constructed. (JN)

Kruglak, Haym; Campbell, Don

1983-01-01

254

High-resolution grazing-incidence grating spectrometer for temperature measurements of low-Z ions emitting in the 100-300 spectral banda)  

NASA Astrophysics Data System (ADS)

We have constructed a high-resolution grazing-incidence spectrometer designed for measuring the ion temperature of low-Z elements, such as Li+ or Li2 +, which radiate near 199 and 135 , respectively. Based on measurements at the Livermore Electron Beam Ion Trap we have shown that the instrumental resolution is better than 48 m at the 200 setting and better than 40 m for the 135- range. Such a high spectral resolution corresponds to an instrumental limit for line-width based temperature measurements of about 45 eV for the 199 Li+ and 65 eV for the 135 Li2 + lines. Recently obtained survey spectra from the Lithium Tokamak Experiment at the Princeton Plasma Physics Laboratory show the presence of these lithium emission lines and the expected core ion temperature of approximately 70 eV is sufficiently high to demonstrate the feasibility of utilizing our high-resolution spectrometer as an ion-temperature diagnostic.

Widmann, K.; Beiersdorfer, P.; Magee, E. W.; Boyle, D. P.; Kaita, R.; Majeski, R.

2014-11-01

255

A combined laser-induced breakdown and Raman spectroscopy Echelle system for elemental and molecular microanalysis  

NASA Astrophysics Data System (ADS)

Raman and laser-induced breakdown spectroscopy is integrated into a single system for molecular and elemental microanalyses. Both analyses are performed on the same ~ 0.002 mm 2 sample spot allowing the assessment of sample heterogeneity on a micrometric scale through mapping and scanning. The core of the spectrometer system is a novel high resolution dual arm Echelle spectrograph utilized for both techniques. In contrast to scanning Raman spectroscopy systems, the Echelle-Raman spectrograph provides a high resolution spectrum in a broad spectral range of 200-6000 cm - 1 without moving the dispersive element. The system displays comparable or better sensitivity and spectral resolution in comparison to a state-of-the-art scanning Raman microscope and allows short analysis times for both Raman and laser induced breakdown spectroscopy. The laser-induced breakdown spectroscopy performance of the system is characterized by ppm detection limits, high spectral resolving power (15,000), and broad spectral range (290-945 nm). The capability of the system is demonstrated with the mapping of heterogeneous mineral samples and layer by layer analysis of pigments revealing the advantages of combining the techniques in a single unified set-up.

Hoehse, Marek; Mory, David; Florek, Stefan; Weritz, Friederike; Gornushkin, Igor; Panne, Ulrich

2009-11-01

256

Fiber-coupled high resolution infrared array spectrometer for the Kuiper Airborne Observatory  

NASA Technical Reports Server (NTRS)

A novel cryogenic grating spectrometer (FCAS) is being designed for observations of volatiles in cometary and planetary atmospheres, and in newly forming planetary systems. The instrument features two-dimensional detector arrays coupled to a high-dispersion echelle by infrared fibers, and will achieve a spectral resolving power of about 40,000. The primary observational platform for this instrument will be the Kuiper Airborne Observatory, but it will also be configured for use at ground-based observatories. Initially, the spectrometer will use a 58 x 62, 1- to 5-micron InSb array. Larger-format IR arrays and arrays of different composition, will later be incorporated as they become available. The instrument will be used in two modes. The first uses a large format IR array in the spectral image plane for the customary one-dimensional spectral-one-dimensional spatial coverage. In the second mode, a massive, coherent bundle of infrared transmitting ZrF4 fibers will be installed after the dispersive element, to reformat the two-dimensional array into an elongated one-dimensional array for wide spectral coverage, allowing multiple lines to be measured in a single integration with high sensitivity. The overall instrument design is discussed, and the system sensitivity is estimated.

Glenar, D. A.; Reuter, D.; Mumma, M. J.; Chin, G.; Wiedemann, G.; Jennings, D.

1990-01-01

257

[Design method of convex master gratings for replicating flat-field concave gratings].  

PubMed

Flat-field concave diffraction grating is the key device of a portable grating spectrometer with the advantage of integrating dispersion, focusing and flat-field in a single device. It directly determines the quality of a spectrometer. The most important two performances determining the quality of the spectrometer are spectral image quality and diffraction efficiency. The diffraction efficiency of a grating depends mainly on its groove shape. But it has long been a problem to get a uniform predetermined groove shape across the whole concave grating area, because the incident angle of the ion beam is restricted by the curvature of the concave substrate, and this severely limits the diffraction efficiency and restricts the application of concave gratings. The authors present a two-step method for designing convex gratings, which are made holographically with two exposure point sources placed behind a plano-convex transparent glass substrate, to solve this problem. The convex gratings are intended to be used as the master gratings for making aberration-corrected flat-field concave gratings. To achieve high spectral image quality for the replicated concave gratings, the refraction effect at the planar back surface and the extra optical path lengths through the substrate thickness experienced by the two divergent recording beams are considered during optimization. This two-step method combines the optical-path-length function method and the ZEMAX software to complete the optimization with a high success rate and high efficiency. In the first step, the optical-path-length function method is used without considering the refraction effect to get an approximate optimization result. In the second step, the approximate result of the first step is used as the initial value for ZEMAX to complete the optimization including the refraction effect. An example of design problem was considered. The simulation results of ZEMAX proved that the spectral image quality of a replicated concave grating is comparable with that of a directly recorded concave grating. PMID:19839358

Zhou, Qian; Li, Li-Feng

2009-08-01

258

HIRDES The High-Resolution Double-Echelle Spectrograph for WSO-UV  

E-print Network

- resolution echelle spectrographs ­ the High-Resolution Double-Echelle Spectrograph (HIRDES) ­ and a low-dispersion Observatory (WSO-UV) will provide future access to high-resolution far-UV spectroscopy. WSO

Barnstedt, Jürgen

259

Development of the Colorado High-resolution Echelle Stellar Spectrograph (CHESS)  

NASA Astrophysics Data System (ADS)

A key astrophysical theme that will drive future UV/optical space missions is the life cycle of cosmic matter, from the flow of intergalactic gas into galaxies to the formation and evolution of exoplanetary systems. Spectroscopic systems capable of delivering high resolution with low backgrounds will be essential to addressing these topics. Towards this end, we are developing a rocket-borne instrument that will serve as a pathfinder for future high-sensitivity, highresolution UV spectrographs. The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) will provide 2 km s-1 velocity resolution (R = 150,000) over the 100 - 160 nm bandpass that includes key atomic and molecular spectral diagnostics for the intergalactic medium (H I Lyman-series, O VI, N V, and C IV), exoplanetary atmospheres (H I Lyman-alpha, O I, and C II), and protoplanetary disks (H2 and CO electronic band systems). CHESS uses a novel mechanical collimator comprised of an array of 10 mm x 10 mm stainless steel tubes to feed a low-scatter, 69 grooves mm-1 echelle grating. The cross-disperser is a holographically ruled toroid, with 351 grooves mm-1. The spectral orders can be recorded with either a 40 mm cross-strip microchannel plate detector or a 3.5k x 3.5k ?-doped CCD. The microchannel plate will deliver 30 ?m spatial resolution and employs new 64 amp/axis electronics to accommodate high count rate observations of local OB stars. CHESS is scheduled to be launched aboard a NASA Terrier/Black Brant IX sounding rocket from White Sands Missile Range in the summer of 2013.

France, Kevin; Beasley, Matthew; Kane, Robert; Nell, Nicholas; Burgh, Eric B.; Green, James C.

2012-09-01

260

The Polychromator: A programmable MEMS diffraction grating for synthetic spectra  

SciTech Connect

The authors report here the design, fabrication and demonstration of an electrostatically actuated MEMS diffractive optical device, the Polychromator grating. The Polychromator grating enables a new type of correlation spectrometer for remote detection of a wide range of chemical species, offering electronic programmability, high specificity and sensitivity, fast response and ruggedness. Significant results include: (1) The first demonstrations of user-defined synthetic spectra in the 3-5 {micro}m wavelength regime based upon controlled deflection of individual grating elements in the Polychromator grating; (2) The first demonstration of gas detection by correlation spectroscopy using synthetic spectra generated by the Polychromator grating.

HOCKER,G.B.; YOUNGNER,D.; BUTLER,MICHAEL A.; SINCLAIR,MICHAEL B.; PLOWMAN,THOMAS E.; DEUTSCH,E.; VOLPICELLI,A.; SENTURIA,S.; RICCO,A.J.

2000-04-17

261

Normal incidence spectrophotometer using high density transmission grating technology and highly efficiency silicon photodiodes for absolute solar EUV irradiance measurements  

Microsoft Academic Search

New developments in transmission grating and photodiode technology now make it possible to realize spectrometers in the extreme ultraviolet (EUV) spectral region (wavelengths less than 1000 A) which are expected to be virtually constant in their diffraction and detector properties. Time dependent effects associated with reflection gratings are eliminated through the use of free standing transmission gratings. These gratings together

H. S. Ogawa; D. McMullin; D. L. Judge; R. Korde

1992-01-01

262

IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 52, NO. 3, MARCH 2005 419 Silicon-Based Micro-Fourier Spectrometer  

E-print Network

concepts were transferred from the macro to the microscale like grating spectrometers [1], [2], Fabry on a sensor chip. Grating spectrometers and classical Fourier spectrometer do not allow for the dense-Fourier Spectrometer Dietmar Knipp, Member, IEEE, Helmut Stiebig, Sameer R. Bhalotra, Student Member, IEEE, Eerke Bunte

Miller, David A. B.

263

Development of Off-Plane Reflection Grating Alignment Fixtures  

NASA Astrophysics Data System (ADS)

Currently, grating spectrometers are used onboard the Chandra X-ray Observatory and XMM-Newton in orbit around the Earth. However, future goals of greater spectral resolving power and greater effective areas necessitate a new generation of high-quality spectrometers. Off-plane reflection gratings can be used to provide high throughput and spectral resolution in the 0.3-2.0 keV band, allowing for unprecedented diagnostics of energetic astrophysical processes. A grating spectrometer consists of multiple aligned gratings intersecting the converging beam of a Wolter-I telescope. Each grating will be aligned such that the diffracted spectra overlap at the focal plane. Misalignments will degrade both spectral resolution and effective area. With analytical alignment tolerances calculated, laboratory techniques to achieve these tolerances for flight-like optics must be developed. We present the results from our first and second generation alignment fixtures, as well as wavefront stitching methods.

Donovan, Benjamin D; Allured, Ryan; McEntaffer, Randall L.

2014-06-01

264

H.O.R.S. a new visiting instrument for G.T.C. based on the Utrecht Echelle Spectrograph  

NASA Astrophysics Data System (ADS)

The High Optical Resolution Spectrograph (HORS) is a proposed high-resolution spectrograph for the 10-m Gran Telescopio Canarias (GTC) based on components from UES, a spectrograph which was in use at the 4.2-m William Herschel Telescope (WHT) between 1992 and 2001. HORS is designed as a cross-dispersed echelle spectrograph to observe in the range 380-800 nm with a FWHM resolving power of about 50,000. HORS would operate on the GTC as a general-purpose high-resolution spectrograph, and it would serve as a test-bed for some of the technologies proposed for ESPRESSO - an ultra-high stability spectrograph planned for the Very Large Telescope (VLT) of the European Southern Observatory. The HORS spectrograph will be placed in the Coud room, where it can enjoy excellent thermal and mechanical stability, fiber fed from the Nasmyth focus, which is shared with OSIRIS. Inside the spectrograph, incoming light will hit a small folder mirror before reaching the collimator. After a second folder, the light will go through a set of three prisms and an Echelle grating before entering the spectrograph camera and, finally, reaching the detector. This manuscript contains a summary of the whole process that has transformed UES into HORS, with all the mechanical and optical modifications that have been introduced to reach the final layout.

Peate, Jos; Gracia, Felix; Allende, Carlos; Calvo, Juan; Santana, Samuel

2014-07-01

265

An Extreme Ultraviolet Spectrometer Leonid V. Didkovsky, Darrell L. Judge, and Andrew R. Jones  

E-print Network

Grating Spectrometer (EGS) is a normal incidence Rowland circle spectrograph with a spectral range of 25. A typical transmission grating spectrometer for EUV measurements from a sounding rocket was basedAn Extreme Ultraviolet Spectrometer Leonid V. Didkovsky, Darrell L. Judge, and Andrew R. Jones

Didkovsky, Leonid

266

Evaluation of gratings for the Extreme Ultraviolet Explorer  

NASA Technical Reports Server (NTRS)

Extensive grating calibration facilities have been developed at the Space Sciences Laboratory at Berkley, which are now being used for the evaluation of the gratings for the spectrometer on the Extreme Ultraviolet Explorer. Measurements of efficiency scattering and imaging quality can be made at wavelengths from 44A to 2500A.

Mrowka, Stan; Martin, Chris; Bowyer, Stuart; Malina, Roger F.

1986-01-01

267

Echelle spectra image processing for the International Ultraviolet Explorer  

NASA Technical Reports Server (NTRS)

This paper presents the techniques needed to convert the International Ultraviolet Explorer (IUE) high-resolution echelle spectra into useful scientific data. The image is obtained with a digitally controlled vidicon camera system. The processes that must be carried out on the image include: noise removal, correction for geometric and optical distortion, nonuniform photometric corrections, and two-dimensional wavelength determination. Results from the breadboard camera system are presented.

Klinglesmith, D. A.; Dunford, E.

1975-01-01

268

Athermalized low-loss echelle-grating-based multimode dense wavelength division demultiplexer  

E-print Network

. Qiao jie@alumni.utexas.net is now with LNL Technologies, One Broadway, 14th Floor, Cambridge, Massachusetts 02139. J. W. Horwitz and W. W. Morey were with Radiant Photonics Incorporated, 12100 Tech- nology

Chen, Ray

269

The AXAF CCD imaging spectrometer  

NASA Technical Reports Server (NTRS)

The current status of the instrument design and the status of the CCDs being fabricated for the AXAF CCD Imaging Spectrometer (ACIS) are summarized. The instrument consists of an image recording array of CCDs and a linear arrangement of CCDs to record the spectra formed by the objective grating spectrometer. Both arrays employ CCDs with pixel dimensions which correspond to about 0.5 arcsec samples of the image. The CCDs provide moderate spectral resolution and good detection efficiency over the energy range 0.5 to 10 keV. Spectral resolution of 200 or more is achievable using the objective grating with the grating array. Radiation damage effects are shown to degrade the energy resolution of CCDs. Specially designed CCD pixel architecture is employed together with shielding and low temperature operation to slow the effects of radiation damage.

Garmire, G. P.; Ricker, G. R.; Bautz, M. W.; Burke, B.; Burrows, D. N.; Collins, S. A.; Doty, J. P.; Gendreau, K.; Lumb, D. H.; Nousek, J. A.

1992-01-01

270

Temporal dispersion of a spectrometer.  

PubMed

The temporal dispersion of an optical spectrometer has been characterized for a variety of conditions related to optical diagnostics to be fielded at the National Ignition Facility (e.g., full-aperture backscatter station, Thomson scattering). Significant time smear is introduced into these systems by the path length difference through the spectrometer. The temporal resolution is shown to depend only on the order of the grating, wavelength, and the number of grooves illuminated. To enhance the temporal resolution, the spectral gratings can be masked limiting the number of grooves illuminated. Experiments have been conducted to verify these calculations. The size and shape of masks are investigated and correlated with the exact shape of the temporal instrument function, which is required when interpreting temporally resolved data. The experiments used a 300 fs laser pulse and a picosecond optical streak camera to determine the temporal dispersion. This was done for multiple spectral orders, gratings, and optical masks. PMID:19044687

Visco, A; Drake, R P; Froula, D H; Glenzer, S H; Pollock, B B

2008-10-01

271

Atmospheric chemistry suite (ACS): a set of infrared spectrometers for atmospheric measurements on board ExoMars trace gas orbiter  

NASA Astrophysics Data System (ADS)

The ACS package for ExoMars Trace Gas Orbiter is a part of Russian contribution to ExoMars ESA-Roscosmos mission. On the Orbiter it complements NOMAD investigation and is intended to recover in much extent the science lost with the cancellation of NASA MATMOS and EMCS infrared sounders. ACS includes three separate spectrometers, sharing common mechanical, electrical, and thermal interfaces. NIR is a versatile spectrometer for the spectral range of 0.7-1.6 ?m with resolving power of ~20000. It is conceived on the principle of RUSALKA/ISS or SOIR/Venus Express experiments combining an echelle spectrometer and an AOTF (Acousto-Optical Tuneable Filter) for order selection. Up to 8 diffraction orders, each 10-20 nm wide can be measured in one sequence record. NIR will be operated principally in nadir, but also in solar occultations, and possibly on the limb. MIR is a high-resolution echelle instrument exclusively dedicated to solar occultation measurements in the range of 2.2-4.4 ?m targeting the resolving power of 50000. The order separation is done by means of a steerable grating cross-disperser, allowing instantaneous coverage of up to 300-nm range of the spectrum for one or two records per second. MIR is dedicated to sensitive measurements of trace gases, approaching MATMOS detection thresholds for many species. TIRVIM is a 2- inch double pendulum Fourier-transform spectrometer for the spectral range of 1.7-17 ?m with apodized resolution varying from 0.2 to 1.6 cm-1. TIRVIM is primarily dedicated to monitoring of atmospheric temperature and aerosol state in nadir, and would contribute in solar occultation to detection/reducing of upper limits of some components absorbing beyond 4 ?m, complementing MIR and NOMAD. Additionally, TIRVIM targets the methane mapping in nadir, using separate detector optimized for 3.3-?m range. The concept of the instrument and in more detail the optical design and the expected parameters of its three parts, channel by channel are described.

Korablev, Oleg; Grigoriev, Alexei V.; Trokhimovsky, Alexander; Ivanov, Yurii S.; Moshkin, Boris; Shakun, Alexei; Dziuban, Ilia; Kalinnikov, Yurii K.; Montmessin, Franck

2013-09-01

272

Holographic optical grating and method for optimizing monochromator configuration  

DOEpatents

This invention comprises a novel apparatus for recording a holographic groove pattern on a diffraction grating blank. The recording apparatus is configured using newly developed groups of analytical equations. The invention further comprises the novel holographic diffraction grating made with the inventive recording apparatus. The invention additionally comprises monochromators and spectrometers equipped with the inventive holographic diffraction grating. Further, the invention comprises a monochromator configured to reduce aberrations using a newly developed group of analytical equations. Additionally, the invention comprises a method to reduce aberrations in monochromators and spectrometers using newly developed groups of analytical equations.

Koike, Masato (Moraga, CA)

1999-01-01

273

Multiple order common path spectrometer  

NASA Technical Reports Server (NTRS)

The present invention relates to a dispersive spectrometer. The spectrometer allows detection of multiple orders of light on a single focal plane array by splitting the orders spatially using a dichroic assembly. A conventional dispersion mechanism such as a defraction grating disperses the light spectrally. As a result, multiple wavelength orders can be imaged on a single focal plane array of limited spectral extent, doubling (or more) the number of spectral channels as compared to a conventional spectrometer. In addition, this is achieved in a common path device.

Newbury, Amy B. (Inventor)

2010-01-01

274

Mathematical Simulation for Integrated Linear Fresnel Spectrometer Chip  

NASA Technical Reports Server (NTRS)

A miniaturized solid-state optical spectrometer chip was designed with a linear gradient-gap Fresnel grating which was mounted perpendicularly to a sensor array surface and simulated for its performance and functionality. Unlike common spectrometers which are based on Fraunhoffer diffraction with a regular periodic line grating, the new linear gradient grating Fresnel spectrometer chip can be miniaturized to a much smaller form-factor into the Fresnel regime exceeding the limit of conventional spectrometers. This mathematical calculation shows that building a tiny motionless multi-pixel microspectrometer chip which is smaller than 1 cubic millimter of optical path volume is possible. The new Fresnel spectrometer chip is proportional to the energy scale (hc/lambda), while the conventional spectrometers are proportional to the wavelength scale (lambda). We report the theoretical optical working principle and new data collection algorithm of the new Fresnel spectrometer to build a compact integrated optical chip.

Park, Yeonjoon; Yoon, Hargoon; Lee, Uhn; King, Glen C.; Choi, Sang H.

2012-01-01

275

Research directed toward improved echelles for the ultraviolet  

NASA Technical Reports Server (NTRS)

Research was undertaken to demonstrate that improved efficiencies for low frequency gratings are obtainable with the careful application of present technology. The motivation for the study was the desire to be assured that the grating-efficiency design goals for potential Space Telescope spectrographs can be achieved. The work was organized to compare gratings made with changes in the three specific parameters: the ruling tool profile, the coating material, and the lubricants used during the ruling process. A series of coatings and test gratings were fabricated and were examined for surface smoothness with a Nomarski Differential Interference Microscope and an electron microscope. Photomicrographs were obtained to show the difference in smoothness of the various coatings and rulings. Efficiency measurements were made for those test rulings that showed good groove characteristics: smoothness, proper ruling depth, and absence of defects. The intuitive feeling that higher grating efficiency should be correlated with the degree of smoothness of both the coating and the grating is supported by the results.

1977-01-01

276

ORFEUS II Echelle spectra: molecular hydrogen at high velocities toward HD 93521  

NASA Astrophysics Data System (ADS)

Absorption lines of interstellar molecular hydrogen in the far ultraviolet (FUV) have been observed in the spectrum of the O9.5 halo star HD 93521, located some 1500 pc from the Galactic plane. During the second ORFEUS-SPAS mission a spectrum with the Echelle spectrometer has been recorded with a total integration time of 1740 s. The resolution achieved was about lambda /Delta lambda >= 10.000 with a signal-to-noise ratio of up to 25. For the first time two components of molecular hydrogen have been observed in absorption at velocities of =~ -12 km s-1 in the Galactic disk and at =~ -62 km s-1 located presumably in the Galactic halo. The column densities derived from a standard curve of growth analysis were found to be N(H2) = 1017.0 cm-2 for the disk component and N(H2) = 1014.6 cm-2 respectively for the component located in the Galactic halo.

Gringel, W.; Barnstedt, J.; de Boer, K. S.; Grewing, M.; Kappelmann, N.; Richter, P.

2000-06-01

277

ESPRESSO: the Echelle spectrograph for rocky exoplanets and stable spectroscopic observations  

Microsoft Academic Search

ESPRESSO, the Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, will combine the efficiency of modern echelle spectrograph design with extreme radial-velocity precision. It will be installed on ESO's VLT in order to achieve a gain of two magnitudes with respect to its predecessor HARPS, and the instrumental radialvelocity precision will be improved to reach cm\\/s level. Thanks to

Francesco A. Pepe; Stefano Cristiani; Rafael Rebolo Lopez; Nuno C. Santos; Antonio Amorim; Gerardo Avila; Willy Benz; Piercarlo Bonifacio; Alexandre Cabral; Pedro Carvas; Roberto Cirami; Joo Coelho; Maurizio Comari; Igor Coretti; Vincenzo de Caprio; Hans Dekker; Bernard Delabre; Paolo di Marcantonio; Valentina D'Odorico; Michel Fleury; Ramn Garca; Jos Miguel Herreros Linares; Ian Hughes; Olaf Iwert; Jorge Lima; Jean-Louis Lizon; Gaspare Lo Curto; Christophe Lovis; Antonio Manescau; Carlos Martins; Denis Mgevand; Andr Moitinho; Paolo Molaro; Mario Monteiro; Manuel Monteiro; Luca Pasquini; Christoph Mordasini; Didier Queloz; Jos L. Rasilla; Jos M. Rebordo; Samuel Santana Tschudi; Paolo Santin; Danuta Sosnowska; Paolo Span; Fabio Tenegi; Stphane Udry; Eros Vanzella; Matteo Viel; Maria Rosa Zapatero Osorio; Filippo Zerbi

2010-01-01

278

Design Study of an Adaptive Optics Visual Echelle Spectrograph and Imager for the VLT  

E-print Network

Design Study of an Adaptive Optics Visual Echelle Spectrograph and Imager for the VLT R study for an adaptive optics visual echelle spectrograph and imager/coronograph for use as parallel instrument of the Nasmyth Adaptive Optics System (NAOS) on unit UT3 (Melipal) of the VLT. The spectrograph

279

[The integrative design for imaging spectrometer].  

PubMed

The hyperspectrum imaging spectrometer will achieve miniaturization and high spectrum resolution and high space resolution along with development of the hyperspectrum imaging technology that is becoming a trend. This trend requires the designers to improve and optimize their designing constantly in designing the instruments. The present paper carried out a method of integrative design for imaging spectrometer. This method suggested that the design and optimization work of the disperse systems of imaging spectrometers would take into account the whole systems, but not consider themselves only. It would get a perfect result by using this method. This paper also explained in details how the method can be used in the design course of imaging spectrometer with convex grating which has been used widely recently. Finally, this paper validated the method by testing the imaging spectrometer with convex grating, which was developed using this method. PMID:22582665

Cui, Ji-cheng; Liu, Yu-juan; Pan, Ming-zhong; Tang, Yu-guo

2012-03-01

280

Multilayer coated gratings for phase-contrast computed tomography (CT)  

NASA Astrophysics Data System (ADS)

By using the principle of grating interferometry, X-ray phase contrast imaging can now be performed with incoherent radiation from standard X-ray tube. This approach is in stark contrast with imaging methods using coherent synchrotron X-ray sources or micro-focus sources to improve contrast. The gratings interferometer imaging technique is capable of measuring the phase shift of hard X-rays travelling through a sample, which greatly enhances the contrast of low absorbing specimen compared to conventional amplitude contrast images. The key components in this approach are the gratings which consists of alternating layers of high and low Z (atomic number) materials fabricated with high aspect ratios. Here we report on a novel method of fabricating the grating structures using the technique of electron-beam (ebeam) thin film deposition. Alternating layers of silicon (Z=14) and tungsten (Z=74) were deposited, each measuring 100 nm each, on a specially designed echelle substrate, which resulted in an aspect ratio of ~100:1. Fabrication parameters related to the thin film deposition such as geometry, directionality, film adhesion, stress and the resulting scanning electron micrographs will be discussed in detail. Using e-beam method large-area gratings with precise multilayer coating thicknesses can be fabricated economically circumventing the expensive lithography steps.

Marton, Zsolt; Bhandari, Harish B.; Wen, Harold H.; Nagarkar, Vivek V.

2014-03-01

281

November 1, 2001 / Vol. 26, No. 21 / OPTICS LETTERS 1645 Transform spectrometer based on measuring the periodicity  

E-print Network

spectrometer, including Fabry­Perot inter- ferometers,1 grating-based spectrometers,2 Michelson spectrometers,3November 1, 2001 / Vol. 26, No. 21 / OPTICS LETTERS 1645 Transform spectrometer based on measuring a compact transform spectrometer based on measuring the periodicity of Talbot self-images. The system has

Miller, David A. B.

282

A compact multichannel spectrometer for Thomson scattering.  

PubMed

The availability of high-efficiency volume phase holographic (VPH) gratings and intensified CCD (ICCD) cameras have motivated a simplified, compact spectrometer for Thomson scattering detection. Measurements of T(e) < 100 eV are achieved by a 2971 l?mm VPH grating and measurements T(e) > 100 eV by a 2072 l?mm VPH grating. The spectrometer uses a fast-gated (~2 ns) ICCD camera for detection. A Gen III image intensifier provides ~45% quantum efficiency in the visible region. The total read noise of the image is reduced by on-chip binning of the CCD to match the 8 spatial channels and the 10 spectral bins on the camera. Three spectrometers provide a minimum of 12 spatial channels and 12 channels for background subtraction. PMID:23126988

Schoenbeck, N L; Schlossberg, D J; Dowd, A S; Fonck, R J; Winz, G R

2012-10-01

283

Varied line-space gratings: past, present and future  

SciTech Connect

A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs.

Hettrick, M.C.

1985-08-01

284

MEMS-based Ultra-Spectrometer (MEMUS): Status Report  

NASA Technical Reports Server (NTRS)

Micro-electromechanical system technology (MEMS) is allowing the development of a radical new design for compact spectrometers that provide both a survey and high resolution spectrograph in one instrument without mechanically changing gratings.

Castracane, J.; Schultz, P. H.; Gutin, M. A.; Gutin, O. N.

2000-01-01

285

Development of Multiple-Element Flame Emission Spectrometer Using CCD Detection  

ERIC Educational Resources Information Center

The full wavelength coverage of charge coupled device (CCD) detector when coupled with an echelle spectrography, the system allows for simultaneously multiple element spectroscopy to be performed. The multiple-element flame spectrometer was built and characterized through the analysis of environmentally significant elements such as Ca, K, Na, Cu,

Seney, Caryn S.; Sinclair, Karen V.; Bright, Robin M.; Momoh, Paul O.; Bozeman, Amelia D.

2005-01-01

286

Monolithic spectrometer  

DOEpatents

A monolithic spectrometer is disclosed for use in spectroscopy. The spectrometer is a single body of translucent material with positioned surfaces for the transmission, reflection and spectral analysis of light rays.

Rajic, Slobodan (Knoxville, TN); Egert, Charles M. (Oak Ridge, TN); Kahl, William K. (Knoxville, TN); Snyder, Jr., William B. (Knoxville, TN); Evans, III, Boyd M. (Oak Ridge, TN); Marlar, Troy A. (Knoxville, TN); Cunningham, Joseph P. (Oak Ridge, TN)

1998-01-01

287

Catwalk grate lifting tool  

DOEpatents

A device is described for lifting catwalk grates comprising an elongated bent member with a handle at one end and a pair of notched braces and a hook at the opposite end that act in conjunction with each other to lock onto the grate and give mechanical advantage in lifting the grate. 10 figs.

Gunter, L.W.

1992-08-11

288

Miniature spectrometers for biochemical analysis  

Microsoft Academic Search

Miniature spectrometers have been demonstrated by mounting micromachined diffraction gratings onto CCD imaging devices. Two implementations are tested: one for high-dispersion and -sensitivity applications, and the other for low-cost consumer applications. The first system shows a dispersion of 1.7 nm\\/pixel and a resolution of 74.4 for the bandwidth of interest. The free spectral range of the device is designed to

Gaylin M Yee; Nadim I Maluf; Paul A Hing; Michael Albin; Gregory T. A Kovacs

1997-01-01

289

Transmission Grating Measurements of Undulator K  

SciTech Connect

This study was undertaken to understand the practicalities of determine K differences in the undulator modules by measuring single-shot x-ray spectra of the spontaneous radiation with a transmissive grating spectrometer under development to measure FEL spectra. Since the quality of the FEL is dependent on a uniform K value in all the undulator modules, being able to measure the relative undulator K values is important. Preliminary results were presented in a presentation, ''Use of FEL Off-Axis Zone Plate Spectrometer to Measure Relative K by the Pinhole/Centroid Method'', at the ''LCLS Beam-Based Undulator K Measurements Workshop'' on November 14, 2005 (UCRL-PRES-217281). This study applies equally well to reflective gratings of the appropriate period and inclinations.

Bionta, R M; Ott, L L

2006-05-15

290

Transmission Grating Measurements of Undulator K  

SciTech Connect

This study was undertaken to understand the practicalities of determine K differences in the undulator modules by measuring single-shot x-ray spectra of the spontaneous radiation with a transmissive grating spectrometer under development to measure FEL spectra. Since the quality of the FEL is dependent on a uniform K value in all the undulator modules, being able to measure the relative undulator K values is important. Preliminary results were presented in a presentation, 'Use of FEL Off-Axis Zone Plate Spectrometer to Measure Relative K by the Pinhole/Centroid Method', at the 'LCLS Beam-Based Undulator K Measurements Workshop' on November 14, 2005 (UCRL-PRES-217281). This study applies equally well to reflective gratings of the appropriate period and inclinations.

Bionta, R. M.

2010-12-01

291

The Polar Environment Atmospheric Research Laboratory UVvisible Ground-Based Spectrometer: First measurements of O3, NO2, BrO,  

E-print Network

­visible, triple-grating spectrometer and is very similar to the UT-GBS (University of Toronto- GBS), which has of the refurbishment of PEARL, a UV­visible diffraction grating spectrometer, the PEARL-GBS (PEARL-Ground- BasedThe Polar Environment Atmospheric Research Laboratory UV­visible Ground-Based Spectrometer: First

Strong, Kimberly

292

Multilayer dielectric diffraction gratings  

DOEpatents

The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described.

Perry, Michael D. (Livermore, CA); Britten, Jerald A. (Oakley, CA); Nguyen, Hoang T. (Livermore, CA); Boyd, Robert (Livermore, CA); Shore, Bruce W. (Livermore, CA)

1999-01-01

293

Spectrometer and scanner with optofluidic configuration.  

PubMed

We present a spectrometer and scanner based on optofluidic configurations. The main optical component of the spectrometer is a compound optical element consisting of an optofluidic lens and standard blazed diffraction grating. The spectrum size can be changed by filling the lens cavity with different liquids. The scanner comprises two hollow 45 angle prisms oriented at 90 to each other. By changing the liquid inside the prisms, two-dimensional light beam scanning can be performed. PMID:23338199

Calixto, Sergio; Rosete-Aguilar, Martha; Sanchez-Morales, Maria Eugenia; Calixto-Solano, Margarita

2013-01-20

294

[Design of concave grating for ultraviolet-spectrum].  

PubMed

Ultraviolet-spectrum technology is a kind of low signal and multianalysis technology. For taking full advantage of spectral information and reducing the volume of spectrometer, we used high efficiency spectroscopy structure based on concave grating. Based on concave grating theory and optic design software ZEMAX, a flat field concave grating for ultraviolet spectrophotometer was designed from primary structure, which relied on global optimization of the software. The contradiction between wide spectrum bound and limited spectrum extension was resolved, aberrations were reduced successfully, spectrum information was utilized fully, and the optic structure of spectrometer was highly efficient. For better preference of this spectrophotometer, after get the structure parameter, combine grating fabrication condition with practice working condition, grating diffractive theory, holographic optics theory and software PCG rate was used for diffraction efficiency design and improve. A paradigm of flat field concave grating is given, it works between 190 nm to 410 nm, the diameter of the concave grating is 20 mm, and F/# is 0.21. The design result was analyzed and evaluated. It was showed that if the slit source, whose width is 50 microm, is used to reconstruction, the theoretic resolution capacity is better than 3 nm. PMID:22870673

Luo, Biao; Wen, Zhi-Yu; Wen, Zhong-Quan; Zeng, Tian-Ling

2012-06-01

295

Toroidal Varied-Line Space (TVLS) Gratings  

NASA Technical Reports Server (NTRS)

It is a particular challenge to develop a stigmatic spectrograph for XUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar EUV (Extreme Ultraviolet) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrometers based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Thomas, Roger J.; Oegerle, William (Technical Monitor)

2002-01-01

296

Sub-nm resolution cavity enhanced micro-spectrometer  

E-print Network

Sub-nm resolution cavity enhanced micro- spectrometer Bernardo B. C. Kyotoku1,2 , Long Chen1: A novel on-chip spectrometer device using combined functionalities of a micro-ring resonator and a planar diffraction grating is proposed. We investigate the performance of this architecture by implementing

Lipson, Michal

297

Noise analysis of spectrometers based on speckle pattern reconstruction.  

PubMed

Speckle patterns produced by a disordered medium or a multimode fiber can be used as a fingerprint to uniquely identify the input light frequency. Reconstruction of a probe spectrum from the speckle pattern has enabled the realization of compact, low-cost, and high-resolution spectrometers. Here we investigate the effects of experimental noise on the accuracy of the reconstructed spectra. We compare the accuracy of a speckle-based spectrometer to a traditional grating-based spectrometer as a function of the probe signal intensity and bandwidth. We find that the speckle-based spectrometers provide comparable performance to a grating-based spectrometer when measuring intense or narrowband probe signals, whereas the accuracy degrades in the measurement of weak or broadband signals. These results are important to identify the applications that would most benefit from this new class of spectrometer. PMID:24514126

Redding, Brandon; Popoff, Sebastien M; Bromberg, Yaron; Choma, Michael A; Cao, Hui

2014-01-20

298

Reflective diffraction grating  

DOEpatents

Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

Lamartine, Bruce C. (Los Alamos, NM)

2003-06-24

299

CD Spectrometer  

NSDL National Science Digital Library

In this activity, learners use a compact disc to make a spectrometer, an instrument used to measure properties of light. Learners use their spectrometer to view a continuous spectrum produced by fluorescent light. This lesson guide also includes instructions on how to build a spectroscope from a cereal box.

Doherty, Paul

2000-01-01

300

Frequency comb based spectrometer for in situ and real time measurements of IO, BrO, NO?, and H?CO at pptv and ppqv levels.  

PubMed

We report an instrument designed for trace gas measurement of highly reactive halogenated radicals, such as bromine oxide and iodine oxide, as well as for nitrogen dioxide and formaldehyde. This compact and robust spectrometer relies on an alternated injection of a frequency-doubled femtosecond radiation at 338 and 436 nm into two parallel high-finesse cavities, for measuring BrO + H(2)CO, and IO + NO(2), respectively. The transmission of the broadband radiation through the cavity is analyzed with a high resolution, compact spectrograph consisting of an echelle grating and a high sensitivity CCD camera. The transportable instrument fits on a breadboard 120 60 cm size and is suitable for in situ and real time measurements of these species. A field campaign at the Marine Boundary Layer in Roscoff (in the northwest of France, 48.7N, 4.0W) during June 2011 illustrates the outstanding performance of the instrument, which reaches a bandwidth normalized minimum absorption coefficient of 1.3 10(-11) cm(-1) Hz(-1/2) per spectral element, and provides detection levels as low as 20 parts per quadrillion of IO in 5 min of acquisition. PMID:22889080

Grilli, Roberto; Mjean, Guillaume; Kassi, Samir; Ventrillard, Irne; Abd-Alrahman, Chadi; Romanini, Daniele

2012-10-01

301

Mariner 10 ultraviolet spectrometer - Airglow experiment  

NASA Technical Reports Server (NTRS)

An extreme ultraviolet airglow spectrometer was flown on Mariner 10 to examine the atmosphere of Venus and Mercury. An objective grating spectrometer was used with channel electron multipliers at fixed positions in the image plane to continuously monitor the resonance-scattered emission rate of expected atomic atmospheric constituents He, H, A, Ne, O and C. A mechanical collimator placed in the entrance aperture of the spectrometer provided spectral separation of 19 A over the wavelength range from He/+/ at 304 A to C at 1657 A and provided spatial separation of 0.125 deg consistent with the spacecraft and trajectory capabilities. The calibration techniques are discussed.

Broadfoot, A. L.; Clapp, S. S.; Stuart, F. E.

1977-01-01

302

Biopolymer holographic diffraction gratings  

NASA Astrophysics Data System (ADS)

Surface-relief diffraction gratings are holographically recorded in dextran sensitized with ammonium dichromate (DCD). DCD was exposed with single-frequency 200 mW diode pumped ND-YAG laser, at 532 nm. The diffraction grating profiles were analyzed by atomic force microscopy (AFM). It was found that different surface profiles could be obtained. Gratings with 330 lines/mm spatial frequencies were made. Existence of higher harmonics in Fourier Transform of non-sinusoidal profiles shows that DCD is capable of recording spatial frequencies up to 1320 lines/mm (four times fundamental frequency). The measured maximum relief depth of the DCD grating is 402 nm.

Savi? evi?, Svetlana; Panteli?, Dejan

2008-03-01

303

Micro spectrometer for parallel light and method of use  

NASA Technical Reports Server (NTRS)

A spectrometer system includes an optical assembly for collimating light, a micro-ring grating assembly having a plurality of coaxially-aligned ring gratings, an aperture device defining an aperture circumscribing a target focal point, and a photon detector. An electro-optical layer of the grating assembly may be electrically connected to an energy supply to change the refractive index of the electro-optical layer. Alternately, the gratings may be electrically connected to the energy supply and energized, e.g., with alternating voltages, to change the refractive index. A data recorder may record the predetermined spectral characteristic. A method of detecting a spectral characteristic of a predetermined wavelength of source light includes generating collimated light using an optical assembly, directing the collimated light onto the micro-ring grating assembly, and selectively energizing the micro-ring grating assembly to diffract the predetermined wavelength onto the target focal point, and detecting the spectral characteristic using a photon detector.

Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor)

2011-01-01

304

Design of high-resolution grazing-incidence echelle monochromators  

SciTech Connect

A grazing-incidence configuration to achieve high spectral resolution in the extreme ultraviolet and soft x-ray regions is presented. It adopts a grating in the off-plane mount operated at high diffracted orders. Resolutions in the 10{sup 5} range can be achieved in a relatively compact size. The monochromator can be tuned in a complete octave by using different diffracted orders without changing the geometrical parameters of the configuration. The optical design of the configuration and the application to a beamline for free-electron-laser radiation centered at 120 eV are discussed.

Poletto, Luca; Frassetto, Fabio

2009-10-01

305

Deformed ellipsoidal diffraction grating blank  

NASA Technical Reports Server (NTRS)

The Deformed Ellipsoidal Grating Blank (DEGB) is the primary component in an ultraviolet spectrometer. Since one of the major concerns for these instruments is throughput, significant efforts are made to reduce the number of components and subsequently reflections. Each reflection results in losses through absorption and scattering. It is these two sources of photon loss that dictated the requirements for the DEGB. The first goal is to shape the DEGB in such a way that the energy at the entrance slit is focused as well as possible on the exit slit. The second goal is to produce a surface smooth enough to minimize the photon loss due to scattering. The program was accomplished in three phases. The first phase was the fabrication planning. The second phase was the actual fabrication and initial testing. The last phase was the final testing of the completed DEGB.

Decew, Alan E., Jr.

1994-01-01

306

Development of off-plane gratings for WHIMex and IXO  

NASA Astrophysics Data System (ADS)

Future X-ray astronomical missions will need to address a number of important goals such as studying the dynamics of clusters of galaxies, determining how elements are created in the explosions of massive stars, and revealing most of the "normal" matter in the universe which is currently thought to be hidden in hot filaments of gas stretching between galaxies. In order to achieve these goals, spectrometers capable of high resolution and high throughput are necessary for the lowest X-ray energies, 0.3-1.0 keV. We present recent progress in the development of off-plane reflection grating technology for use on upcoming missions. Off-plane grating spectrometers consist of an array of gratings capable of reaching resolutions above 3000 (?/??). Concept designs have been made for the International X-ray Observatory X-ray Grating Spectrometer. More recently however, we have designed an Optics Module Assembly for WHIMex, an Explorer mission concept that incorporates a Wolter telescope, steering flats, and an array of gratings. This paper will discuss these designs and the application of off-plane arrays for the future.

McEntaffer, Randall L.; Cash, Webster; Lillie, Chuck; Casement, Suzanne; Zhang, Will; Holland, Andrew; Murray, Neil; O'Dell, Stephen; Schattenburg, Mark; Heilmann, Ralf; Tsunemi, Hiroshi

2011-09-01

307

High-resolution crystal spectrometer for the 1060 extreme ultraviolet region  

E-print Network

in the soft x-ray region below 25 ?. Above this wavelength grating spectrometers have been used, but oftenHigh-resolution crystal spectrometer for the 10­60 ? extreme ultraviolet region P. Beiersdorfer spectrometer with nominal resolving power approaching 1000 is described for measuring emission lines

Wargelin, Bradford J.

308

In situ calibration of an extreme ultraviolet spectrometer for attosecond transient  

E-print Network

- periments. Generally, an XUV spectrometer consists of a grazing incidence flat-field grating (FFGIn situ calibration of an extreme ultraviolet spectrometer for attosecond transient absorption January 2013 We report a method for calibrating an extreme ultraviolet spectrometer based on a flat

Van Stryland, Eric

309

Using a multimode fiber as a high-resolution, low-loss spectrometer  

E-print Network

the ca- libration data. This approach allows the grating in a tra- ditional spectrometer to be replacedUsing a multimode fiber as a high-resolution, low-loss spectrometer Brandon Redding and Hui Cao as a high-resolution, low-loss spec- trometer. The proposed spectrometer consists only of the fiber

Cao, Hui

310

Integrating fiber Bragg grating sensors with sensor networks  

Microsoft Academic Search

Optical fiber Bragg grating sensors exhibit specialized sensing characteristics for harsh environments. The most common interrogation methods for FBGs require high resolution spectrometers that are not well suited to some embedded test situations. We have developed a compact, high speed, Ethernet-enabled interrogator that consumes less than 10 Watts. We describe the conventions used to convert from the optical domain to

Wesley Kunzler; Zixu Zhu; Richard Selfridge; Stephen Schultz; Michael Wirthlin

2008-01-01

311

ISO observations of Titan with SWS/grating  

NASA Technical Reports Server (NTRS)

The observations of Titan performed by the Infrared Space Observatory (ISO) short wavelength spectrometer (SWS), in the 2 micrometer to 45 micrometer region using the grating mode, are reported on. Special attention is given to data from Titan concerning 7 micrometer to 45 micrometer spectral resolution. Future work for improving Titan's spectra investigation is suggested.

Coustenis, A.; Encrenaz, T.; Salama, A.; Lellouch, E.; Gautier, D.; Kessler, M. F.; deGraauw, T.; Samuelson, R. E.; Bjoraker, G.; Orton, G.

1997-01-01

312

Precise angular positioning at 6K: the FIFI-LS grating assembly  

NASA Astrophysics Data System (ADS)

The Field Imaging Far Infrared Line Spectrometer (FIFI-LS) obtains spectral data within two wavelength ranges. The observed wavelengths are set by rotating the two diffraction gratings to specific angles. This paper describes on the grating assemblies, designed to rotate and stabilize the gratings. First the assembly itself and its special environment inside FIFI-LS is explained. Then a method is layed out how to monitor the performance of the drive and how to detect upcoming failures before they happen. The last chapter is dedicated to first inflight measurements of the position stability of the grating.

Rebell, Felix; Raab, Walfried; Colditz, Sebastian; Beckmann, Simon; Bryant, Aaron; Fischer, Christian; Fumi, Fabio; Geis, Norbert; Hnle, Rainer; Klein, Randolf; Krabbe, Alfred; Looney, Leslie; Poglitsch, Albrecht; Ragan, Sarah; Savage, Maureen

2014-07-01

313

Performance of high spatial frequency X-ray transmission gratings  

NASA Technical Reports Server (NTRS)

The performance of high spatial frequency 'phased' X-ray transmission gratings developed for the High Energy Transmission Grating Spectrometer on the Advanced X-ray Astrophysics FAcility (AXAF) is examined. The gratings tested here nominally consist of 1-micron-thick gold lines of 0.2 micron period covering approximately 5 sq cm of a polyimide membrane. A table-top setup at MIT employs the gratings in reflection to diffract UV (325 nm) laser light. It is used to measure grating periods and indicates that period variations within and between gratings are a few parts in 10,000. Tests performed at the Marshall Space Flight Center 304 m X-ray Facility using 1.5 keV X-rays in transmission corroborate the UV measurements and demonstrate geometrically-limited resolving powers of E/Delta E about 750. Finally, X-ray transmission tests performed in the MIT 25 m X-ray facility provide measurements of period, line thickness, space-to-period ratio, tilt of grating lines, and efficiency.

Fischbach, K. F.; Levine, A. M.; Schattenburg, M. L.; Dewey, D.; Renshaw, R. L.

1988-01-01

314

Resolution-enhanced Mapping Spectrometer  

NASA Technical Reports Server (NTRS)

A familiar mapping spectrometer implementation utilizes two dimensional detector arrays with spectral dispersion along one direction and spatial along the other. Spectral images are formed by spatially scanning across the scene (i.e., push-broom scanning). For imaging grating and prism spectrometers, the slit is perpendicular to the spatial scan direction. For spectrometers utilizing linearly variable focal-plane-mounted filters the spatial scan direction is perpendicular to the direction of spectral variation. These spectrometers share the common limitation that the number of spectral resolution elements is given by the number of pixels along the spectral (or dispersive) direction. Resolution enhancement by first passing the light input to the spectrometer through a scanned etalon or Michelson is discussed. Thus, while a detector element is scanned through a spatial resolution element of the scene, it is also temporally sampled. The analysis for all the pixels in the dispersive direction is addressed. Several specific examples are discussed. The alternate use of a Michelson for the same enhancement purpose is also discussed. Suitable for weight constrained deep space missions, hardware systems were developed including actuators, sensor, and electronics such that low-resolution etalons with performance required for implementation would weigh less than one pound.

Kumer, J. B.; Aubrun, J. N.; Rosenberg, W. J.; Roche, A. E.

1993-01-01

315

Reduction of spectra exposed by the fiber-fed echelle spectrograph HEROS  

NASA Astrophysics Data System (ADS)

We present a manual for the reduction of data exposed by the fiber-fed echelle spectrograph HEROS. As the reduction process is really not trivial in fiber echelle spectrography (mainly due to instabilities leading to wave-like patterns in merged spectrum), we remind and discuss the most important influences (if they are known) evoking cited instabilities. Nevertheless, the main accent is put on the reduction process description, list of MIDAS commands, and finally on the description of HEROS arrangement of some MIDAS routines.

Skoda, Petr; Slechta, Miroslav

316

HyTES: Thermal Imaging Spectrometer Development  

NASA Technical Reports Server (NTRS)

The Jet Propulsion Laboratory has developed the Hyperspectral Thermal Emission Spectrometer (HyTES). It is an airborne pushbroom imaging spectrometer based on the Dyson optical configuration. First low altitude test flights are scheduled for later this year. HyTES uses a compact 7.5-12 micrometer m hyperspectral grating spectrometer in combination with a Quantum Well Infrared Photodetector (QWIP) and grating based spectrometer. The Dyson design allows for a very compact and optically fast system (F/1.6). Cooling requirements are minimized due to the single monolithic prism-like grating design. The configuration has the potential to be the optimal science-grade imaging spectroscopy solution for high altitude, lighter-than-air (HAA, LTA) vehicles and unmanned aerial vehicles (UAV) due to its small form factor and relatively low power requirements. The QWIP sensor allows for optimum spatial and spectral uniformity and provides adequate responsivity which allows for near 100mK noise equivalent temperature difference (NEDT) operation across the LWIR passband. The QWIP's repeatability and uniformity will be helpful for data integrity since currently an onboard calibrator is not planned. A calibration will be done before and after eight hour flights to gage any inconsistencies. This has been demonstrated with lab testing. Further test results show adequate NEDT, linearity as well as applicable earth science emissivity target results (Silicates, water) measured in direct sunlight.

Johnson, William R.; Hook, Simon J.; Mouroulis, Pantazis; Wilson, Daniel W.; Gunapala, Sarath D.; Realmuto, Vincent; Lamborn, Andy; Paine, Chris; Mumolo, Jason M.; Eng, Bjorn T.

2011-01-01

317

Aluminum nitride grating couplers.  

PubMed

Grating couplers in sputtered aluminum nitride, a piezoelectric material with low loss in the C band, are demonstrated. Gratings and a waveguide micromachined on a silicon wafer with 600 nm minimum feature size were defined in a single lithography step without partial etching. Silicon dioxide (SiO(2)) was used for cladding layers. Peak coupling efficiency of -6.6 dB and a 1 dB bandwidth of 60 nm have been measured. This demonstration of wire waveguides and wideband grating couplers in a material that also has piezoelectric and elasto-optic properties will enable new functions for integrated photonics and optomechanics. PMID:22695653

Ghosh, Siddhartha; Doerr, Christopher R; Piazza, Gianluca

2012-06-10

318

The reduction of fiber-fed echelle spectrograph data: Methods and an IDL-based solution procedure  

NASA Astrophysics Data System (ADS)

Echelle spectrograph data present several challenges in data reduction. In this paper we address the general problem of accurately extracting spectra from a night's worth of raw charge coupled devices (CCD) fiber-fed echelle data frames. We first briefly review echelle spectroscopy; properties of the basic echelle spectrograph, how the orders are arranged on the CCD, and what demands and constraints this data format places on reduction algorithms. We then discuss solutions to the various problems for fiber-fed data, with particular emphasis on the removal of the scattered-light background. Finally, we discuss our implementation of these solutions. We have written a package using the Interactive Data Language (IDL) that uses the methods described in this paper to give accurate extractions of spectra from fiber-fed echelle frames with any number of spectral orders of arbitrary tilt and curvature. We describe how interested persons may obtain the package through anonymous FTP.

Hall, Jeffrey C.; Fulton, Eliza E.; Huenemoerder, David P.; Welty, Alan D.; Neff, James E.

1994-03-01

319

Performance of volume phase holographic transmission grating recorded in DCG for PGP  

NASA Astrophysics Data System (ADS)

The volume phase holographic (VPH) transmission grating recorded in dichromate gelatin (DCG) with a specific spectral coverage from 420 nm to 760 nm is designed for a novel prism-grating-prism imaging spectrometer. Based on the Rigorous Coupled-Wave Analysis, its performances are predicted and analyzed. The grating is manufactured and its properties are measured experimentally. The diffraction efficiency over the spectral range, the bandwidth, and the angular selectivity of the grating is measured, analyzed and compared with that of the theoretical ones. The results show that by adjusting and controlling the preparation conditions of DCG plates, the exposure time and the post-processing technique of the grating, the VPH transmission grating with high diffraction efficiency approximate to the design requirement can be obtained. The measured peak diffraction efficiency reaches nearly 85% at central wavelength of 590 nm while the average diffraction efficiency is larger than 75% over the required spectral range from 420 nm to 760 nm.

Li, Ming; Tang, Minxue; Xia, Haohan; Fang, Chunhuan; Wu, Jianhong; Zhao, Xunjie

2010-11-01

320

New family of reflective spectrometers  

NASA Astrophysics Data System (ADS)

Three kinds of spectrometers based on off-axis Schmidt and Schmidt-Cassegrain cameras are presented; they have been used for several instruments studies, mainly for European Space Agency and Agenzia Spaziale Italiana. Both dispersive prism and grating based configurations have interesting characteristics, such as: simplicity, low cost, high efficiency, small volume and weight, very low sensitivity to polarization and great flexibility also in multichannel (wavebands) configurations. The image quality is high, even with low relative apertures and great fields of view, allowing a very good correction of smile and keystone. The compensation of the slit curvature induced by a prism disperser is also demonstrated. This family of spectrometers was the topic of three patents, belonging to Selex-Galileo, while the intellectual property belongs to A. Romali et al.

Romoli, Andrea; Simonetti, Francesca; Gambicorti, Lisa; Marchi, Alessandro Zuccaro

2011-01-01

321

Subwavelength gratings and applications  

NASA Astrophysics Data System (ADS)

This Ph. D thesis investigates the fabrication and applications of subwavelength gratings. The first objective of this study is aimed at finding low-cost, high throughput fabrication techniques that are capable of producing high-quality nano-scale gratings over a relatively large scale. The second objective is to explore the applications of nano-scale gratings in subwavelength optical elements (SOE), a new type of compact, highly efficient optical devices that are compatible with semiconductor device fabrication technologies and have the potential to be suitable for integration. This thesis is divided into 5 chapters. Chapter 1 is an introduction to the subject of gratings. A brief review of the evolution of different grating fabrication methods and applications is included in this chapter. Chapters 2, 3, and Chapter 4 of the thesis are devoted to the question of nano-scale grating fabrication. Technologies concerning the generation of high spatial-frequency periodic patterns over a large scale using interference lithography (IL) are covered in Chapter 2. The role of nanoimprint lithography (NIL) as a low-cost replication tool for the production of nano-gratings is discussed in detail in Chapters 3 and 4. More specifically: Chapter 3 presents several NIL-based technologies that are used to overcome some of the limitations inherent with the interference lithography fabrication process; Chapter 4 presents a novel mask technology promising for the large-scale production of gratings by NIL. Finally, several applications of nano-scale gratings in subwavelength optical elements (SOE) are discussed in Chapter 5. Most of the SOE devices investigated in this study are based on the birefringence and the index-averaging effects of nano-gratings in the long-wavelength domain. A brief summary of the general theory 103--104 proposed by P.Yeh et al. concerning the optical properties of subwavelength gratings can be found in Appendix A. Since the orientation-dependent wet chemical etching of silicon was used extensively in this research, a relatively detailed discussion of this technique is also included in Appendix B of this dissertation.

Yu, Zhaoning

322

Color separation gratings  

NASA Technical Reports Server (NTRS)

In this paper, we describe the theory, fabrication and test of a binary optics 'echelon'. The echelon is a grating structure which separates electromagnetic radiation of different wavelengths, but it does so according to diffraction order rather than by dispersion within one diffraction order, as is the case with conventional gratings. A prototype echelon, designed for the visible spectrum, is fabricated using the binary optics process. Tests of the prototype show good agreement with theoretical predictions.

Farn, Michael W.; Knowlden, Robert E.

1993-01-01

323

Alignment of the grating wheel mechanism for a ground-based cryogenic near-infrared astronomy instrument  

Microsoft Academic Search

We describe the population, optomechanical alignment, and alignment verification of near-infrared gratings on the grating wheel mechanism (GWM) for the Infrared Multi-Object Spectrometer (IRMOS). IRMOS is a cryogenic (80 K), principle investigator-class instrument for the 2.1 m and Mayall 3.8 m telescopes at Kitt Peak National Observatory, and a MEMS spectrometer concept demonstrator for the James Webb Space Telescope. The

Sharon M. Gutkowski; Raymond G. Ohl; Jason E. Hylan; John G. Hagopian; Stephen E. Kraft; J. E. Mentzell; Joseph A. Connelly; Joseph P. Schepis; Leroy M. Sparr; Matthew A. Greenhouse; John W. MacKenty

2003-01-01

324

Performance characteristics of the new Keck Observatory echelle spectrograph and imager  

Microsoft Academic Search

The Echelle Spectrograph and Imager (ESI) is a multipurpose instrument which has been delivered by the Instrument Development Laboratory of Lick Observatory for use at the Cassegrain focus of the Keck II telescope. ESI saw first light on August 29, 1999. The optical performance of the instrument has been measured using artificial calibration sources and starlight. Measurements of the average

Andrew I. Sheinis; Joseph S. Miller; Michael Bolte; Brian M. Sutin

2000-01-01

325

Unexpected effects of a trap in CCD echelle spectra of B-type stars  

NASA Astrophysics Data System (ADS)

Because of the nature of echelle spectra, cosmetic defects such as traps may mimic real spectral features. An example from spectra taken at CTIO with a GEC CCD is presented, and it is shown how the affected pixels can be eliminated from the reduced spectrum, at a slight cost in signal-to-noise ratio.

Morrison, Nancy D.; Zimba, Jason R.

1990-06-01

326

Unexpected effects of a trap in CCD echelle spectra of B-type stars  

NASA Technical Reports Server (NTRS)

Because of the nature of echelle spectra, cosmetic defects such as traps may mimic real spectral features. An example from spectra taken at CTIO with a GEC CCD is presented, and it is shown how the affected pixels can be eliminated from the reduced spectrum, at a slight cost in signal-to-noise ratio.

Morrison, Nancy D.; Zimba, Jason R.

1990-01-01

327

HIRDES The High-Resolution Double-Echelle Spectrograph for the World  

E-print Network

-Resolution Double-Echelle Spectrograph, HIRDES) and a low-dispersion long-slit instrument. Within HIRDES the 102-UV spectroscopy. WSO/UV is an international collaboration led by Russia (Roscosmos) to build a UV (102­310 nm is spectroscopy, high spatial-resolution UV imaging instruments are foreseen. Additionally, a direct imager which

Barnstedt, Jürgen

328

FIES: A high resolution FIber fed Echelle Spectro-graph for NOT  

E-print Network

;nancial problems and change of the responsible group for the construction, an instrument has only seen the ESO 1.5m) responsible A. Kaufer at Heidelberg. FIES is a cross dispersed (large prism) Echelle. This unit is being redesigned to make it simpler and easy to modify. Details follow later. 2. Two o#11;-axis

Frandsen, Søren

329

HISS spectrometer  

SciTech Connect

This talk describes the Heavy Ion Spectrometer System (HISS) facility at the Lawrence Berkeley Laboratory's Bevalac. Three completed experiments and their results are illustrated. The second half of the talk is a detailed discussion of the response of drift chambers to heavy ions. The limitations of trajectory measurement over a large range in incident particle charge are presented.

Greiner, D.E.

1984-11-01

330

High performance Si immersion gratings patterned with electron beam lithography  

NASA Astrophysics Data System (ADS)

Infrared spectrographs employing silicon immersion gratings can be significantly more compact than spectro- graphs using front-surface gratings. The Si gratings can also offer continuous wavelength coverage at high spectral resolution. The grooves in Si gratings are made with semiconductor lithography techniques, to date almost entirely using contact mask photolithography. Planned near-infrared astronomical spectrographs require either finer groove pitches or higher positional accuracy than standard UV contact mask photolithography can reach. A collaboration between the University of Texas at Austin Silicon Diffractive Optics Group and the Jet Propulsion Laboratory Microdevices Laboratory has experimented with direct writing silicon immersion grating grooves with electron beam lithography. The patterning process involves depositing positive e-beam resist on 1 to 30 mm thick, 100 mm diameter monolithic crystalline silicon substrates. We then use the facility JEOL 9300FS e-beam writer at JPL to produce the linear pattern that defines the gratings. There are three key challenges to produce high-performance e-beam written silicon immersion gratings. (1) E- beam field and subfield stitching boundaries cause periodic cross-hatch structures along the grating grooves. The structures manifest themselves as spectral and spatial dimension ghosts in the diffraction limited point spread function (PSF) of the diffraction grating. In this paper, we show that the effects of e-beam field boundaries must be mitigated. We have significantly reduced ghost power with only minor increases in write time by using four or more field sizes of less than 500 ?m. (2) The finite e-beam stage drift and run-out error cause large-scale structure in the wavefront error. We deal with this problem by applying a mark detection loop to check for and correct out minuscule stage drifts. We measure the level and direction of stage drift and show that mark detection reduces peak-to-valley wavefront error by a factor of 5. (3) The serial write process for typical gratings yields write times of about 24 hours- this makes prototyping costly. We discuss work with negative e-beam resist to reduce the fill factor of exposure, and therefore limit the exposure time. We also discuss the tradeoffs of long write-time serial write processes like e-beam with UV photomask lithography. We show the results of experiments on small pattern size prototypes on silicon wafers. Current prototypes now exceed 30 dB of suppression on spectral and spatial dimension ghosts compared to monochromatic spectral purity measurements of the backside of Si echelle gratings in reflection at 632 nm. We perform interferometry at 632 nm in reflection with a 25 mm circular beam on a grating with a blaze angle of 71.6. The measured wavefront error is 0.09 waves peak to valley.

Gully-Santiago, Michael A.; Jaffe, Daniel T.; Brooks, Cynthia B.; Wilson, Daniel W.; Muller, Richard E.

2014-07-01

331

Ultraviolet spectrometer experiment for the Voyager mission  

NASA Technical Reports Server (NTRS)

An objective grating spectrometer covering the wavelength range of 500 to 1700 A with a 10-A resolution is employed for the Voyager ultraviolet spectrometer experiment. In determining the composition and structure of the atmospheres of Saturn, Jupiter and several satellites, the ultraviolet spectrometer will rely on airglow mode observations to measure radiation from the atmospheres due to resonant scattering of solar flux, and the occultation mode for assessments of the atmospheric extinction of solar or stellar radiation as the spacecraft enters shadow zones. Since it is capable of prolonged stellar observations in the 500 to 1000 A wavelength range, the spectrometer is expected to make important contributions to exploratory studies of UV sources.

Broadfoot, A. L.; Sandel, B. R.; Shemansky, D. E.; Atreya, S. K.; Donahue, T. M.; Moos, H. W.; Bertaux, J. L.; Blamont, J. E.; Ajello, J. M.; Strobel, D. F.

1977-01-01

332

Miniaturized MOEMS spectrometer for NIR applications  

NASA Astrophysics Data System (ADS)

Optical spectroscopy is a common tool for many applications. Micro systems most often use fixed gratings and array detectors. In the infrared wavelength range above the limit for Si-detectors (1100nm) and Ge-detectors (1700nm) respectively, this is either very expensive or almost impossible. Micro opto electro mechanical systems (MOEMS) offer very promising options. A movable grating can be realized by a silicon chip, using the technology of a well established scanner mirror chips in combination with the realization of a reflective grating either through etching of the aluminium mirror layer or even a more sophisticated technology. The patented resonant drive realizes a mechanical angle of +/-7 with CMOS compatible voltages of approximately 20V. This technology leads to the realization of a set up close to a classical Czerny-Turner spectrometer using a single detector only. The device offers the capability to be scaled down to the size of a cigarette box. The spectrometer presented here was adjusted to 900...2500nm range. The scanning grating chip has either 500, 625 or 714 lines/mm. As detector serves a fast InGaAs photodiode, read out through a 12 Bit AD converter. The sinusoidal movement is unfolded by a signal processor (TI TMS320F2812) which also computes the spectrum. Acquired data can be shown by a display or transmitted to a host PC. System tests have been performed using infrared LEDs. Wavelengths have been 1300, 1400 or 1550nm for example. The spectrometer is working accurately. First result of micro shaped grating structures to enhance the sensitivity are presented.

Grueger, Heinrich; Heberer, Andreas; Zimmer, Fabian; Wolter, Alexander; Schenk, Harald

2005-08-01

333

[Development of X-ray Reflection Grating Technology for the Constellation-X Mission  

NASA Technical Reports Server (NTRS)

This Grant supports MIT technology development of x-ray reflection gratings for the Constellation-X Reflection Grating Spectrometer (RGS). Since the start of the Grant MIT has extended its previously-developed patterning and super-smooth, blazed grating fabrication technology to ten-times smaller grating periods and ten-times larger blaze angles to demonstrate feasibility and performance in the off-plane grating geometry. In the past year we have focused our efforts on extending our Nanoruler grating fabrication tool to enable it to perform variable-period scanning-beam interference lithography (VP-SBIL). This new capability required extensive optical and mechanical improvements to the system. The design phase of this work is largely completed and key components are now on order and assembly has begun. Over the next several months the new VP-SBIL Nanoruler system will be completed and testing begun. We have also demonstrated a new technique for patterning gratings using the Nanoruler called Doppler mode, which will be important for patterning the radial groove gratings for the RGS using the new VP-SBIL system. Flat and thin grating substrates will be critical for the RGS. In the last year we demonstrated a new technique for flattening thin substrates using magneto-rheologic fluid polishing (MRF) and achieved 2 arcsecond flatness with a 0.5 mm-thick substrate-a world's record. This meets the Con X requirement for grating substrate flatness.

Schattenburg, Mark L.

2005-01-01

334

Imaging IR spectrometer, phase 2  

NASA Technical Reports Server (NTRS)

The development is examined of a prototype multi-channel infrared imaging spectrometer. The design, construction and preliminary performance is described. This instrument is intended for use with JPL Table Mountain telescope as well as the 88 inch UH telescope on Mauna Kea. The instrument is capable of sampling simultaneously the spectral region of 0.9 to 2.6 um at an average spectral resolution of 1 percent using a cooled (77 K) optical bench, a concave holographic grating and a special order sorting filter to allow the acquisition of the full spectral range on a 128 x 128 HgCdTe infrared detector array. The field of view of the spectrometer is 0.5 arcsec/pixel in mapping mode and designed to be 5 arcsec/pixel in spot mode. The innovative optical design has resulted in a small, transportable spectrometer, capable of remote operation. Commercial applications of this spectrometer design include remote sensing from both space and aircraft platforms as well as groundbased astronomical observations.

Gradie, Jonathan; Lewis, Ralph; Lundeen, Thomas; Wang, Shu-I

1990-01-01

335

The Bragg crystal spectrometer for AXAF  

NASA Technical Reports Server (NTRS)

The goal of MIT's high resolution X-ray spectrometry investigation on the Advanced X-ray Astrophysics Facility is to study the physical conditions in celestial sources by means of detailed measurements of their X-ray spectra. The investigation involves two complimentary dispersive instruments, a Bragg crystal spectrometer (BCS) and a high energy transmission grating spectrometer. Particular attention is given to the BCS which will be used to measure the strengths of individual lines from both point and extended objects in order to apply plasma diagnostic techniques to the study of cosmic X-ray sources.

Canizares, C. R.; Markert, T. H.; Clark, G. W.

1986-01-01

336

An Extreme Ultraviolet Optics-Free Spectrometer With Improved Spectral Resolution and High Signal-to-Noise Ratio  

E-print Network

the spectral resolution of typical EUV grating spectrometers designed for spaceflight applications. ModeledAn Extreme Ultraviolet Optics-Free Spectrometer With Improved Spectral Resolution and High Signal (EUV) spectrometer based on a gas ionization chamber and on flight experience of the Optics Free

Didkovsky, Leonid

337

Pupil aberrations in Offner spectrometers.  

PubMed

The light path function (LPF) of an Offner spectrometer is presented. The evaluation of the LPF of this spectrometer enables its imaging properties to be studied for arbitrary object and image positions, while avoiding the more complicated analysis of intermediate images generated by the diffraction grating, which is often involved. A power series expansion of the LPF on the grating coordinates directly determines pupil aberrations of the generated spectrum and facilitates the search for configurations with small low-order aberrations. This analysis not only confirms the possibility of reducing low-order aberrations in Rowland-type mounts, namely astigmatism and coma, as predicted in previous studies, but also proves that all third-order terms in the series expansion of the aberration function can be canceled at the image of the design point and for the corresponding design wavelength, when the design point is located on a plane orthogonal to the optical axis. Furthermore, fourth-order terms are computed and shown to represent the most relevant contribution to image blurring. Third- and fourth-order aberrations are also evaluated for Rowland mounts with the design point located outside the aforementioned plane. The study described in this manuscript is not restricted to small angles of incidence, and, therefore, it goes beyond Seidel and Buchdahl aberrations. PMID:22472819

Gonzlez-Nez, Hctor; Prieto-Blanco, Xess; de la Fuente, Ral

2012-04-01

338

Calibration of a High Resolution Soft X-ray Spectrometer  

SciTech Connect

A high resolution grating spectrometer (HRGS) with 2400 line/mm variable line spacing grating for the 10-50 {angstrom} wavelength range has been designed for laser-produced plasma experiments at the Lawrence Livermore National Laboratory (LLNL). The spectrometer has a large radius of curvature, R=44.3 m, is operated at a 2{sup o} grazing angle and can record high signal-to-noise spectra when used with a low-noise, cooled, charge-coupled device detector. The instrument can be operated with a 10-25 {micro}m wide slit to achieve the best spectral resolving power on laser plasma sources, approaching 2000, or in slitless mode with a small symmetrical emission source. Results will be presented for the spectral response of the spectrometer cross-calibrated at the LLNL Electron Beam Ion Trap facility using the broadband x-ray energy EBIT Calorimeter Spectrometer (ECS).

Dunn, J; Beiersdorfer, P; Brown, G V; Magee, E W

2010-01-26

339

Fiber Bragg grating sensor and waveguide grating sensor  

Microsoft Academic Search

Several new designes of different type fiber Bragg grating(FBG) sensors, including long range strain sensor, pressure sensor, and displacement sensor, have been introduced. A new concept of sliced fiber Bragg grating as free space optical element has been presented. Some new waveguide Bragg grating writing technologies have been introduced.

Pin Long

2011-01-01

340

Birefringence Bragg Binary (3B) grating, quasi-Bragg grating and immersion gratings  

NASA Astrophysics Data System (ADS)

A volume phase holographic (VPH) grating achieves high angular dispersion and very high diffraction efficiency for the first diffraction order and for S or P polarization. However the VPH grating could not achieve high diffraction efficiency for non-polarized light at a large diffraction angle because properties of diffraction efficiencies for S and P polarizations are different. Furthermore diffraction efficiency of the VPH grating extinguishes toward a higher diffraction order. A birefringence binary Bragg (3B) grating is a thick transmission grating with optically anisotropic material such as lithium niobate or liquid crystal. The 3B grating achieves diffraction efficiency up to 100% for non-polarized light by tuning of refractive indices for S and P polarizations, even in higher diffraction orders. We fabricated 3B grating with liquid crystal and evaluated the performance of the liquid crystal grating. A quasi-Bragg (QB) grating, which consists long rectangle mirrors aligned in parallel precisely such as a window shade, also achieves high diffraction efficiency toward higher orders. We fabricated QB grating by laminating of silica glass substrates and glued by pressure fusion of gold films. A quasi-Bragg immersion (QBI) grating has smooth mirror hypotenuse and reflector array inside the hypotenuse, instead of step-like grooves of a conventional immersion grating. An incident beam of the QBI grating reflects obliquely at a reflector, then reflects vertically at the mirror surface and reflects again at the same reflector. We are going to fabricate QBI gratings by laminating of mirror plates as similar to fabrication of the QB grating. We will also fabricate silicon and germanium immersion gratings with conventional step-like grooves by means of the latest diamond machining methods. We introduce characteristics and performance of these gratings.

Ebizuka, Noboru; Morita, Shin-ya; Yamagata, Yutaka; Sasaki, Minoru; Bianco, Andorea; Tanabe, Ayano; Hashimoto, Nobuyuki; Hirahara, Yasuhiro; Aoki, Wako

2014-07-01

341

Charged particle accelerator grating  

DOEpatents

A readily disposable and replaceable accelerator grating for a relativistic particle accelerator. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams into the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

Palmer, Robert B. (Shoreham, NY)

1986-01-01

342

Circular Fibonacci gratings.  

PubMed

We introduce circular Fibonacci gratings (CFGs) that combine the concept of circular gratings and Fibonacci structures. Theoretical analysis shows that the diffraction pattern of CFGs is composed of fractal distributions of impulse rings. Numerical simulations are performed with two-dimensional fast Fourier transform to reveal the fractal behavior of the diffraction rings. Experimental results are also presented and agree well with the numerical results. The fractal nature of the diffraction field should be of great theoretical interest, and shows potential to be further developed into practical applications, such as in laser measurement with wideband illumination. PMID:22086040

Gao, Nan; Zhang, Yuchao; Xie, Changqing

2011-11-01

343

Research directed toward improved echelles for the ultraviolet. [large space teslescope spectrographs  

NASA Technical Reports Server (NTRS)

Low frequency gratings obtainable with present technology, can meet the grating-efficiency design goals for potential space telescope spectrographs. Gratings made with changes in the three specific parameters: the ruling tool profile, the coating material, and the lubricants used during the ruling process were compared. A series of coatings and test gratings were fabricated and were examined for surface smoothness with a Nomarski differential interference microscope and an electron microsocope. Photomicrographs were obtained to show the difference in smoothness of the various coatings and rulings. Efficiency measurements were made for those test rulings that showed good groove characteristics: smoothness, proper ruling depth, and absence of defects (e.g., streaks, feathered edges and rough sides). Higher grating efficiency should be correlated with the degree of smoothness of both the coating and the grating groove.

1977-01-01

344

Designing an acousto-optical spectrometer for Guillermo Haro Astrophysical Observatory  

NASA Astrophysics Data System (ADS)

The Guillermo Haro astrophysical observatory (Mexico) realizes investigations in the visible and near-infrared range . Actually, the classical grating spectrometer with mechanically removable optical filters and diffraction gratings is exploited there. Unfortunately, the regular process of changing the diffraction gratings with different resolutions and recalibrating the spectrometer is inconvenient and wastes expensive time for observations. This is why exploiting an acousto-optical cell as a dynamic dispersive element is practically desirable, because potentially it realizes tuning the spectral resolution and the range of observation electronically and excludes filters. Some aspects of inserting just one dynamic acousto-optical diffraction grating instead of a set of the traditional static diffraction gratings are preliminarily considered.

Shcherbakov, Alexandre S.; Arellanes Bernabe, Adan Omar; Chavushyan, Vahram

2013-09-01

345

Raman spectroscopy with an integrated arrayed-waveguide grating.  

PubMed

An integrated arrayed-waveguide grating fabricated in silicon-oxynitride technology is applied to Raman spectroscopy. After its validation by reproducing the well-known spectrum of cyclohexane, polarized Raman spectra are measured of extracted human teeth containing localized initial carious lesions. Excellent agreement is obtained between the spectra of healthy and carious tooth enamel measured with our integrated device and spectra recorded using a conventional Raman spectrometer. Our results represent a step toward the realization of compact, hand-held, integrated spectrometers, e.g. for the detection of dental caries at an early stage. PMID:22139265

Ismail, N; Choo-Smith, L-P; Wrhoff, K; Driessen, A; Baclig, A C; Caspers, P J; Puppels, G J; de Ridder, R M; Pollnau, M

2011-12-01

346

Performance characteristics of the new Keck Observatory echelle spectrograph and imager  

Microsoft Academic Search

The Echelle Spectrograph and Imager (ESI) is a multipurpose instrument which\\u000ahas been delivered by the Instrument Development Laboratory of Lick Observatory\\u000afor use at the Cassegrain focus of the Keck II telescope. ESI saw first light\\u000aon August 29, 1999. The optical performance of the instrument has been measured\\u000ausing artificial calibration sources and starlight. Measurements of the average

A. I. Sheinis; J. Miller; M. Bolte; B. Sutin

2000-01-01

347

Total reduction of distorted echelle spectrograms - An automatic procedure. [for computer controlled microdensitometer  

NASA Technical Reports Server (NTRS)

A total reduction procedure, notable for its use of a computer-controlled microdensitometer for semi-automatically tracing curved spectra, is applied to distorted high-dispersion echelle spectra recorded by an image tube. Microdensitometer specifications are presented and the FORTRAN, TRACEN and SPOTS programs are outlined. The intensity spectrum of the photographic or electrographic plate is plotted on a graphic display. The time requirements are discussed in detail.

Peterson, R. C.; Title, A. M.

1975-01-01

348

StarCAT: A CATALOG OF SPACE TELESCOPE IMAGING SPECTROGRAPH ULTRAVIOLET ECHELLE SPECTRA OF STARS  

Microsoft Academic Search

StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as 'stars', recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2 Ms. For many of the objects, broad ultraviolet coverage has been achieved by

Thomas R. Ayres; Thomas R

2010-01-01

349

PRELIMINARY RESULTS FROM THE HAYABUSA NEAR INFRARED SPECTROMETER (NIRS) OF ASTEROID (25143) ITOKAWA. M. Abe1  

E-print Network

PRELIMINARY RESULTS FROM THE HAYABUSA NEAR INFRARED SPECTROMETER (NIRS) OF ASTEROID (25143) ITOKAWA Bay Area Blvd., Houston, TX 77058, USA). Introduction: NIRS is a near-infrared spectrometer on,000 spectra of Itokawa. NIRS has a 64-channel InGaAs photodiode array detector and a grism grating system [2

Hiroi, Takahiro

350

OBSERVATIONS WITH NEAR INFRARED SPECTROMETER FOR HAYABUSA MISSION IN THE CRUISING PHASE. M. Abe1  

E-print Network

OBSERVATIONS WITH NEAR INFRARED SPECTROMETER FOR HAYABUSA MISSION IN THE CRUISING PHASE. M. Abe1@ithaca.edu). Introduction: NIRS is a near infrared spectrometer on-board the spacecraft HAYABUSA, which aims to return (grating ­ prism) system. Spectral resolution is 23.6nm/channel. The field of view is 0.1 x 0.1 degrees

Hiroi, Takahiro

351

An EUV spectrometer for mapping the heliopause and solar wind , J.Edelsteina  

E-print Network

An EUV spectrometer for mapping the heliopause and solar wind M.Lamptona , J.Edelsteina , T limitation on the mapping rate at high signal-to-noise ratio. We have developed a spectrometer configuration combines a conventional normal-incidence Rowland mount grating and an efficient multilayer coating

California at Berkeley, University of

352

CHARACTERISTICS AND CURRENT STATUS OF NEAR INFRARED SPECTROMETER FOR HAYABUSA MISSION. M. Abe1  

E-print Network

CHARACTERISTICS AND CURRENT STATUS OF NEAR INFRARED SPECTROMETER FOR HAYABUSA MISSION. M. Abe1 , Y materials. Combining with the data from asteroid multiband imaging camera (AMICA) and X-ray spectrometer as a detec- tor and a grism (grating ­ prism) system. Spectral reso- lution is 23.6nm/channel. The second

Hiroi, Takahiro

353

SPICAV on Venus Express: Three spectrometers to study the global structure and composition of the Venus atmosphere  

NASA Astrophysics Data System (ADS)

Spectroscopy for the investigation of the characteristics of the atmosphere of Venus (SPICAV) is a suite of three spectrometers in the UV and IR range with a total mass of 13.9 kg flying on the Venus Express (VEX) orbiter, dedicated to the study of the atmosphere of Venus from ground level to the outermost hydrogen corona at more than 40,000 km. It is derived from the SPICAM instrument already flying on board Mars Express (MEX) with great success, with the addition of a new IR high-resolution spectrometer, solar occultation IR (SOIR), working in the solar occultation mode. The instrument consists of three spectrometers and a simple data processing unit providing the interface of these channels with the spacecraft. A UV spectrometer (118-320 nm, resolution 1.5 nm) is identical to the MEX version. It is dedicated to nadir viewing, limb viewing and vertical profiling by stellar and solar occultation. In nadir orientation, SPICAV UV will analyse the albedo spectrum (solar light scattered back from the clouds) to retrieve SO 2, and the distribution of the UV-blue absorber (of still unknown origin) on the dayside with implications for cloud structure and atmospheric dynamics. On the nightside, ? and ? bands of NO will be studied, as well as emissions produced by electron precipitations. In the stellar occultation mode the UV sensor will measure the vertical profiles of CO 2, temperature, SO 2, SO, clouds and aerosols. The density/temperature profiles obtained with SPICAV will constrain and aid in the development of dynamical atmospheric models, from cloud top (60 km) to 160 km in the atmosphere. This is essential for future missions that would rely on aerocapture and aerobraking. UV observations of the upper atmosphere will allow studies of the ionosphere through the emissions of CO, CO +, and CO 2+, and its direct interaction with the solar wind. It will study the H corona, with its two different scale heights, and it will allow a better understanding of escape mechanisms and estimates of their magnitude, crucial for insight into the long-term evolution of the atmosphere. The SPICAV VIS-IR sensor (0.7-1.7 ?m, resolution 0.5-1.2 nm) employs a pioneering technology: an acousto-optical tunable filter (AOTF). On the nightside, it will study the thermal emission peeping through the clouds, complementing the observations of both VIRTIS and Planetary Fourier Spectrometer (PFS) on VEX. In solar occultation mode this channel will study the vertical structure of H 2O, CO 2, and aerosols. The SOIR spectrometer is a new solar occultation IR spectrometer in the range ?=2.2-4.3 ?m, with a spectral resolution ?/? ?>15,000, the highest on board VEX. This new concept includes a combination of an echelle grating and an AOTF crystal to sort out one order at a time. The main objective is to measure HDO and H 2O in solar occultation, in order to characterize the escape of D atoms from the upper atmosphere and give more insight about the evolution of water on Venus. It will also study isotopes of CO 2 and minor species, and provides a sensitive search for new species in the upper atmosphere of Venus. It will attempt to measure also the nightside emission, which would allow a sensitive measurement of HDO in the lower atmosphere, to be compared to the ratio in the upper atmosphere, and possibly discover new minor atmospheric constituents.

Bertaux, Jean-Loup; Nevejans, D.; Korablev, O.; Villard, E.; Qumerais, E.; Neefs, E.; Montmessin, F.; Leblanc, F.; Dubois, J. P.; Dimarellis, E.; Hauchecorne, A.; Lefvre, F.; Rannou, P.; Chaufray, J. Y.; Cabane, M.; Cernogora, G.; Souchon, G.; Semelin, F.; Reberac, A.; Van Ransbeek, E.; Berkenbosch, S.; Clairquin, R.; Muller, C.; Forget, F.; Hourdin, F.; Talagrand, O.; Rodin, A.; Fedorova, A.; Stepanov, A.; Vinogradov, I.; Kiselev, A.; Kalinnikov, Yu.; Durry, Georges; Sandel, B.; Stern, A.; Grard, J. C.

2007-10-01

354

Miniature lamellar grating interferometer based on silicon technology  

Microsoft Academic Search

We present a lamellar grating interferometer realized with microelectromechanical system technology. It is used as a time-scanning Fourier-transform spectrometer. The motion is carried out by an electrostatic comb drive actuator fabricated by silicon micromachining, particularly by silicon-on-insulator technology. For the first time to our knowledge, we measure the spectrum of an extended white-light source with a resolution of 1.6 nm

Omar Manzardo; Roland Michaely; Felix Schdelin; Wilfried Noell; Thomas Overstolz; Nico de Rooij; Hans Peter Herzig

2004-01-01

355

Performance characteristics of the new Keck Observatory echelle spectrograph and imager  

E-print Network

The Echelle Spectrograph and Imager (ESI) is a multipurpose instrument which has been delivered by the Instrument Development Laboratory of Lick Observatory for use at the Cassegrain focus of the Keck II telescope. ESI saw first light on August 29, 1999. The optical performance of the instrument has been measured using artificial calibration sources and starlight. Measurements of the average image FWHM in echelle mode are 22 microns (0.22 arcseconds), 16 to 18 microns (0.16 to 0.18 arcseconds) in broad band imaging mode, and comparable in the low-dispersion prismatic mode (LDP). Images on the sky, under best seeing conditions show FWHM sizes of 34 microns (0.34 arcseconds). Maximum efficiencies are measured to be 30% for echelle and anticipated to be greater than 38% for low dispersion prismatic mode including atmospheric, telescope and detector losses. In this paper we describe the instrument and its specifications. We discuss the testing that led to the above conclusions.

A. I. Sheinis; J. Miller; M. Bolte; B. Sutin

2000-10-04

356

Optical system for high resolution spectrometer/monochromator  

DOEpatents

An optical system for use in a spectrometer or monochromator employing a mirror which reflects electromagnetic radiation from a source to converge with same in a plane is disclosed. A straight grooved, varied-spaced diffraction grating receives the converging electromagnetic radiation from the mirror and produces a spectral image for capture by a detector, target or like receiver. 11 figs.

Hettrick, M.C.; Underwood, J.H.

1988-10-11

357

Optical system for high resolution spectrometer/monochromator  

DOEpatents

An optical system for use in a spectrometer or monochromator employing a mirror which reflects electromagnetic radiation from a source to converge with same in a plane. A straight grooved, varied-spaced diffraction grating receives the converging electromagnetic radiation from the mirror and produces a spectral image for capture by a detector, target or like receiver.

Hettrick, Michael C. (Berkeley, CA); Underwood, James H. (Walnut Creek, CA)

1988-01-01

358

High accuracy wavelength calibration for a scanning visible spectrometer  

SciTech Connect

Spectroscopic applications for plasma velocity measurements often require wavelength accuracies {<=}0.2 A. An automated calibration, which is stable over time and environmental conditions without the need to recalibrate after each grating movement, was developed for a scanning spectrometer to achieve high wavelength accuracy over the visible spectrum. This method fits all relevant spectrometer parameters using multiple calibration spectra. With a stepping-motor controlled sine drive, an accuracy of {approx}0.25 A has been demonstrated. With the addition of a high resolution (0.075 arc sec) optical encoder on the grating stage, greater precision ({approx}0.005 A) is possible, allowing absolute velocity measurements within {approx}0.3 km/s. This level of precision requires monitoring of atmospheric temperature and pressure and of grating bulk temperature to correct for changes in the refractive index of air and the groove density, respectively.

Scotti, Filippo; Bell, Ronald E. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2010-10-15

359

The evaluation of a deformable diffraction grating for a stigmatic EUV spectroheliometer  

NASA Technical Reports Server (NTRS)

A high-efficiency, extreme ultraviolet (EUV) imaging spectrometer is constructed and tested. The spectrometer employs a concave toroidal grating illuminated at normal incidence in a Rowland circle mounting and has only one reflecting surface. The toroidal grating has been fabricated by a new technique employing an elastically-deformable sub-master grating replicated in a spherical form and then mechanically distorted to produce the desired aspect ratio of the toroidal surface for stigmatic imaging over the selected wavelength range. The fixed toroidal grating used in the spectrometer is then replicated from this surface. Photographic tests and initial photoelectric tests with a two-dimensional, pulse-counting detector system verify the image quality of the toroidal grating at wavelengths near 600 A. The results of these tests and the basic designs of two instruments which could employ the imaging spectrometer for astrophysical investigations in space are described; i.e., a high-resolution EUV spectroheliometer for studies of the solar chromosphere, transition region, and corona; and an EUV spectroscopic telescope for studies of non-solar objects.

Timothy, J. G.

1987-01-01

360

Design of the CHIRON high-resolution spectrometer at CTIO  

NASA Astrophysics Data System (ADS)

Small telescopes coupled to high resolution spectrometers are powerful tools for Doppler planet searches. They allow for high cadence observations and flexible scheduling; yet there are few such facilities. We present an innovative and inexpensive design for CHIRON, a high resolution (R~80.000) Echelle spectrometer for the 1.5m telescope at CTIO. Performance and throughput are very good, over the whole spectral range from 410 to 870nm, with a peak efficiency of 15% in the iodine absorption region. The spectrograph will be fibre-fed, and use an iodine cell for wavelength calibration. An image slicer permits a moderate beam size. We use commercially available, high performance optical components, which is key for quick and efficient implementation. We discuss the optical design, opto-mechanical tolerances and resulting image quality.

Schwab, Christian; Spronck, Julien F. P.; Tokovinin, Andrei; Fischer, Debra A.

2010-07-01

361

Fabrication of large-area and low mass critical-angle x-ray transmission gratings  

NASA Astrophysics Data System (ADS)

Soft x-ray spectroscopy of celestial sources with high resolving power R = E/?E and large collecting area addresses important science listed in the Astro2010 Decadal Survey New Worlds New Horizons, such as the growth of the large scale structure of the universe and its interaction with active galactic nuclei, the kinematics of galactic outflows, as well as coronal emission from stars and other topics. Numerous studies have shown that a transmission grating spectrometer based on lightweight critical-angle transmission (CAT) gratings can deliver R = 3000-5000 and large collecting area with high efficiency and minimal resource requirements, providing spectroscopic figures of merit at least an order of magnitude better than grating spectrometers on Chandra and XMM-Newton, as well as future calorimeter-based missions. The recently developed CAT gratings combine the advantages of transmission gratings (low mass, relaxed figure and alignment tolerances) and blazed reflection gratings (high broad band diffraction efficiency, utilization of higher diffraction orders). Their working principle based on blazing through reflection off the smooth, ultra-high aspect ratio grating bar sidewalls has previously been demonstrated on small samples with x rays. For larger gratings (area greater than 1 inch square) we developed a fabrication process for grating membranes with a hierarchy of integrated low-obscuration supports. The fabrication involves a combination of advanced lithography and highly anisotropic dry and wet etching techniques. We report on the latest fabrication results of free-standing, large-area CAT gratings with polished sidewalls and preliminary x-ray tests.

Heilmann, Ralf K.; Bruccoleri, Alex R.; Guan, Dong; Schattenburg, Mark L.

2014-07-01

362

The double grating monochromator's design for pure rotational Raman lidar  

NASA Astrophysics Data System (ADS)

The pure rotational Raman lidar temperature measurement system is usually used for retrieval of atmospheric temperature according to the echo signal ratio of high and low-level quantum numbers of N2 molecules which are consistent with the exponential relationship. An effective method to detect the rotational Raman spectrum is taking a double grating monochromator. In this paper the detection principle and the structure of the dual-grating monochromator are described, with analysis of rotational Raman's Stokes and anti-Stokes spectrums of N2 molecule, the high order and lower order quantum number of the probe spectrum are resolved, then the specific design parameters are presented. Subsequently spectral effect is simulated with Zemax software. The simulation result indicates that under the condition of the probe laser wavelength of 532nm and using double-grating spectrometer which is comprised by two blazed gratings, Raman spectrums of 529.05nm, 530.40nm, 533.77nm, 535.13nm can be separated well, and double-grating monochromator has high diffraction efficiency.

Ge, Xian-ying; Chen, He; Zhang, Yin-chao; Chen, Si-ying; Guo, Pan; Mu, Tao-tao; Bu, Zhi-chao; Yang, Jian

2013-09-01

363

Pinhole transmission grating spectrometer of X-ray picosecond frame  

Microsoft Academic Search

The structure principle and performance of the measure system of three-dimensional resolution of time, space and spectrum\\u000a for laser-produced plasma are presented. The typical experimental results are also given.

Jinxiu Cheng; Tianshu Wen; Cunbang Yang; Zhijian Zheng; Jiabin Chen; Shuping Liu; Shaojun Fu; Yiling Hong

1998-01-01

364

Electron-multiplying CCDs for future soft X-ray spectrometers  

Microsoft Academic Search

CCDs have been used in several high resolution soft X-ray spectrometers for both space and terrestrial applications such as the Reflection Grating Spectrometer on XMM-Newton and the Super Advanced X-ray Emission Spectrometer at the Paul Scherrer Institut in Switzerland. However, with their ability to use multiplication gain to amplify signal and suppress readout noise, EM-CCDs are being considered instead of

J H Tutt; A D Holland; N J Murray; R D Harriss; D J Hall; M Soman

2012-01-01

365

Charged particle accelerator grating  

DOEpatents

A readily disposable and replaceable accelerator grating for a relativistic particle accelerator is described. The grating is formed for a plurality of liquid droplets that are directed in precisely positioned jet streams to periodically dispose rows of droplets along the borders of a predetermined particle beam path. A plurality of lasers are used to direct laser beams onto the droplets, at predetermined angles, thereby to excite the droplets to support electromagnetic accelerating resonances on their surfaces. Those resonances operate to accelerate and focus particles moving along the beam path. As the droplets are distorted or destroyed by the incoming radiation, they are replaced at a predetermined frequency by other droplets supplied through the jet streams.

Palmer, R.B.

1985-09-09

366

Test of prototype ITER vacuum ultraviolet spectrometer and its application to impurity study in KSTAR plasmasa)  

NASA Astrophysics Data System (ADS)

To optimize the design of ITER vacuum ultraviolet (VUV) spectrometer, a prototype VUV spectrometer was developed. The sensitivity calibration curve of the spectrometer was calculated from the mirror reflectivity, the grating efficiency, and the detector efficiency. The calibration curve was consistent with the calibration points derived in the experiment using the calibrated hollow cathode lamp. For the application of the prototype ITER VUV spectrometer, the prototype spectrometer was installed at KSTAR, and various impurity emission lines could be measured. By analyzing about 100 shots, strong positive correlation between the O VI and the C IV emission intensities could be found.

Seon, C. R.; Hong, J. H.; Jang, J.; Lee, S. H.; Choe, W.; Lee, H. H.; Cheon, M. S.; Pak, S.; Lee, H. G.; Biel, W.; Barnsley, R.

2014-11-01

367

Compact transform spectrometer based on sampling a standing wave H. L. Kung, S. R. Bhalotra, J. D. Mansell and D. A. B. Miller  

E-print Network

, including Fabry-Perot interferometers,1 grating based spectrometers2 and Michelson FourierCompact transform spectrometer based on sampling a standing wave H. L. Kung, S. R. Bhalotra, J. D demonstrate a Fourier-transform spectrometer based on a large-displacement MEMS mirror and sampling an optical

Miller, David A. B.

368

98 IEEE JOURNAL ON SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 8, NO. 1, JANUARY/FEBRUARY 2002 Standing-Wave Transform Spectrometer  

E-print Network

­Pérot interferometers [1], grating-based spectrometers [2], and Michelson spectrom- eters [3]. Of these designs, only Standing-Wave Transform Spectrometer Based on Integrated MEMS Mirror and Thin-Film Photodetector Helen L, we report a novel, miniature Fourier transform spectrometer with a linear architecture that works

Miller, David A. B.

369

Grating-structured metallic microsprings.  

PubMed

We fabricate grating-structured metallic microsprings with well-defined helical angles and diameters, which are self-rolled from strained nanomembranes patterned with gratings. The grating structures on the metal membrane, replicated from the imprinted polymer layer beneath, give rise to the controlled rolling direction after selective etching of the underlying sacrificial layer. The rolling direction of the grating-structured thin metal film is always perpendicular to the long side edge of gratings, offering a good way to roll up strained strips into well controlled three-dimensional (3D) microsprings simply by altering the dimension and orientation of the structured strips. The mechanical elasticity of these grating-structured metallic microsprings is verified for the potential application as a flow rate sensor. Our work may stimulate rigorous synthesis of highly functional and complex 3D helical micro and nanostructures, and hint a broad range of applications such as environmental sensors, micro-/nanoscale robots, metamaterials, etc. PMID:24728100

Huang, Tao; Liu, Zhaoqian; Huang, Gaoshan; Liu, Ran; Mei, Yongfeng

2014-08-21

370

Holographic grating formation in photopolymers  

NASA Astrophysics Data System (ADS)

We introduce a model describing real-time grating formation in holographic photopolymers, assuming that the diffusion of free monomers is much faster than the grating formation. This model, which combines polymerization kinetics with results from coupled-wave theory, indicates that the grating formation time depends sublinearly on the average holographic recording intensity and the beam intensity ratio controls the grating index modulation at saturation. We validate the model by comparing its predictions with the results of experiments in which DuPont HRF-150X001 photopolymer was used.

Piazzolla, Sabino; Jenkins, B. Keith

1996-07-01

371

Inexpensive photonic crystal spectrometer for colorimetric sensing applications.  

PubMed

Photonic crystal spectrometers possess significant size and cost advantages over traditional grating-based spectrometers. In a previous work [Pervez, et al, Opt. Express 18, 8277 (2010)] we demonstrated a proof of this concept by implementing a 9-element array photonic crystal spectrometer with a resolution of 20 nm. Here we demonstrate a photonic crystal spectrometer with improved performance. The dependence of the spectral recovery resolution on the number of photonic crystal arrays and the width of the response function from each photonic crystal is investigated. A mathematical treatment, regularization based on known information of the spectrum, is utilized in order to stabilize the spectral estimation inverse problem and achieve improved spectral recovery. Colorimetry applications, the measurement of CIE 1931 chromaticities and the color rendering index, are demonstrated with the improved spectrometer. PMID:23481975

Bryan, Kurt M; Jia, Zhang; Pervez, Nadia K; Cox, Marshall P; Gazes, Michael J; Kymissis, Ioannis

2013-02-25

372

A Fourier transform Raman spectrometer with visible laser excitation  

E-print Network

We present the development and performance of a Fourier transformation (FT) based Raman spectrometer working with visible laser (532 nm) excitation. It is generally thought that FT-Raman spectrometers are not viable in the visible range where shot-noise limits the detector performance and therein they are outperformed by grating based, dispersive ones. We show that contrary to this common belief, the recent advances of high-performance interference filters makes the FT-Raman design a valid alternative to dispersive Raman spectrometers for samples which do not luminesce. We critically compare the performance of our spectrometer to two dispersive ones: a home-built single channel and a state-of-the-art CCD based instruments. We demonstrate a similar or even better sensitivity than the CCD based dispersive spectrometer particularly when the laser power density is considered. The instrument possesses all the known advantages of the FT principle of spectral accuracy, high throughput, and economic design. We also d...

Dzsaber, S; Bernth, B; Gyre, B; Fehr, T; Kramberger, C; Pichler, T; Simon, F

2014-01-01

373

Interfacing a Two-Stage Image Intensifier Tube to an Echelle Spectrograph  

NASA Technical Reports Server (NTRS)

An Echelle spectrograph has been in use at the Marshall Space Flight Center for a number of years. Research has been carried out in the study of the internal motions of ionized gas clouds in the interstellar medium. In order to extend the ability of the spectrograph to allow investigations of the faint outer regions of the gas clouds and to make possible the initiatiion of new research programs dealing with the study of sunspots and the zodiacal light, a two-stage image intensifier tube was incorporated into the instrument. The objective of this work was to interface the image tube with the spectrograph.

Flesch, T. R.

1983-01-01

374

FIES: The high-resolution Fiber-fed Echelle Spectrograph at the Nordic Optical Telescope  

NASA Astrophysics Data System (ADS)

FIES is a cross-dispersed high-resolution echelle spectrograph at the 2.56 m Nordic Optical Telescope (NOT), and was optimised for throughput and stability in 2006. The major 2006 upgrade involved the relocation of FIES to a stable environment and development of a fiber bundle that offers 3 different resolution modes, and made FIES an attractive tool for the user community of the NOT. Radial-velocity stability is achieved through double-chamber active temperature control. A dedicated data reduction tool, FIEStool, was developed. As a result of these upgrades, FIES is now one of the work-horse instruments at the NOT.

Telting, J. H.; Avila, G.; Buchhave, L.; Frandsen, S.; Gandolfi, D.; Lindberg, B.; Stempels, H. C.; Prins, S.; NOT staff

2014-01-01

375

[Optimum design of imaging spectrometer based on toroidal uniform-line-spaced (TULS) spectrometer].  

PubMed

Based on the geometrical aberration theory, a optimum-design method for designing an imaging spectrometer based on toroidal uniform grating spectrometer is proposed. To obtain the best optical parameters, twice optimization is carried out using genetic algorithm(GA) and optical design software ZEMAX A far-ultraviolet(FUV) imaging spectrometer is designed using this method. The working waveband is 110-180 nm, the slit size is 50 microm x 5 mm, and the numerical aperture is 0.1. Using ZEMAX software, the design result is analyzed and evaluated. The results indicate that the MTF for different wavelengths is higher than 0.7 at Nyquist frequency 10 lp x mm(-1), and the RMS spot radius is less than 14 microm. The good imaging quality is achieved over the whole working waveband, the design requirements of spatial resolution 0.5 mrad and spectral resolution 0.6 nm are satisfied. It is certificated that the optimum-design method proposed in this paper is feasible. This method can be applied in other waveband, and is an instruction method for designing grating-dispersion imaging spectrometers. PMID:23905368

Xue, Qing-Sheng; Wang, Shu-Rong

2013-05-01

376

Flat field concave holographic grating with broad spectral region and moderately high resolution.  

PubMed

In order to deal with the conflicts between broad spectral region and high resolution in compact spectrometers based on a flat field concave holographic grating and line array CCD, we present a simple and practical method to design a flat field concave holographic grating that is capable of imaging a broad spectral region at a moderately high resolution. First, we discuss the principle of realizing a broad spectral region and moderately high resolution. Second, we provide the practical method to realize our ideas, in which Namioka grating theory, a genetic algorithm, and ZEMAX are used to reach this purpose. Finally, a near-normal-incidence example modeled in ZEMAX is shown to verify our ideas. The results show that our work probably has a general applicability in compact spectrometers with a broad spectral region and moderately high resolution. PMID:22307123

Wu, Jian Fen; Chen, Yong Yan; Wang, Tai Sheng

2012-02-01

377

Chirped diffraction grating optical switching  

NASA Astrophysics Data System (ADS)

While fiber optic Bragg grating sensors have emerged as a viable commercial product and principle component within numerous fiber optic components, they possess the inherent inflexibility that once written, the nonstressed grating spacing is fixed. An alternative method of fabricating Bragg gratings where a photosensitive fiber core material (similar to that used in photogrey sunglasses) exists at the grating site along the fiber has been examined. As opposed to a conventional grating writing method using lateral illumination of the fiber core, in this instance the diffraction rating is written via a deliberate intensity variation in the light which is injected into the fiber. The slight difference in refractive index between the photogrey section of the core and the regular fiber causes an internal Fabry-Perot resonator cavity to be established. By using an intensity-modulated high power laser, the illuminating modulation pattern reflects back and forth within this cavity establishing a standing wave pattern. Different patterns may be launched into the fiber resulting in a grating spacing which is variable. This standing wave pattern effectively illuminates the photogrey section nonuniformly with the high power portions of the standing wave pattern causing more darkening - thereby in essence creating the Bragg diffraction grating. Removal of this illumination source results in a grating that fades away yielding a re-writable component. An examination of this type or re-writable component will be reported along with its suitability for 100- and 5-GHz DWDM applications.

Fuhr, Peter L.; Spremo, Stevan

2002-05-01

378

Normal incidence spectrophotometer using high density transmission grating technology and highly efficiency silicon photodiodes for absolute solar EUV irradiance measurements  

NASA Technical Reports Server (NTRS)

New developments in transmission grating and photodiode technology now make it possible to realize spectrometers in the extreme ultraviolet (EUV) spectral region (wavelengths less than 1000 A) which are expected to be virtually constant in their diffraction and detector properties. Time dependent effects associated with reflection gratings are eliminated through the use of free standing transmission gratings. These gratings together with recently developed and highly stable EUV photodiodes have been utilized to construct a highly stable normal incidence spectrophotometer to monitor the variability and absolute intensity of the solar 304 A line. Owing to its low weight and compactness, such a spectrometer will be a valuable tool for providing absolute solar irradiance throughout the EUV. This novel instrument will also be useful for cross-calibrating other EUV flight instruments and will be flown on a series of Hitchhiker Shuttle Flights and on SOHO. A preliminary version of this instrument has been fabricated and characterized, and the results are described.

Ogawa, H. S.; Mcmullin, D.; Judge, D. L.; Korde, R.

1992-01-01

379

First application close measurements applying the new hybrid integrated MEMS spectrometer  

NASA Astrophysics Data System (ADS)

Grating spectrometers have been designed in many different configurations. Now potential high volume applications ask for extremely miniaturized and low cost systems. By the use of integrated MEMS (micro electro mechanical systems) scanning grating devices a less expensive single detector can be used in the NIR instead of the array detectors required for fixed grating systems. Meanwhile the design of a hybrid integrated MEMS scanning grating spectrometer has been drawn. The MEMS device was fabricated in the Fraunhofer IPMS own clean room facility. This chip is mounted on a small circuit board together with the detector and then stacked with spacer and mirror substrate. The spectrometer has been realized by stacking several planar substrates by sophisticated mounting technologies. The spectrometer has been designed for the 950nm - 1900nm spectral range and 9nm spectral resolution with organic matter analysis in mind. First applications are considered in the food quality analysis and food processing technology. As example for the use of a spectrometer with this performance the grill process of steak was analyzed. Similar measurement would be possible on dairy products, vegetables or fruit. The idea is a mobile spectrometer for in situ and on site analysis applications in or attached to a host system providing processing, data access and input-output capabilities, disregarding this would be a laptop, tablet, smart phone or embedded platform.

Grger, Heinrich; Pgner, Tino; Knobbe, Jens; Schenk, Harald

2013-05-01

380

The Berkeley EUV spectrometer for ORFEUS  

NASA Technical Reports Server (NTRS)

A novel EUV spectrometer is presented for the ORFEUS-SPAS mission. It uses a set of four varied line-space spherical diffraction gratings to obtain high-resolution spectra of point sources at wavelengths between 390 and 1200 A. The spectra are recorded with two detector units, each containing curved-surface microchannel plates and a delay-line anode-readout system. An independent optical system detects the image of the source in the entrance aperture and tracks the source as it drifts during an observation, enabling a reconstruction of the spectra postflight. The overall system performance is discussed and illustrated by synthetic spectra.

Hurwitz, M.; Bowyer, S.

1991-01-01

381

Self-heated fiber Bragg grating sensors  

Microsoft Academic Search

This letter demonstrates an approach for tuning fiber Bragg grating sensors with optical energy carried in the same optical fiber. Optical energy carried in the optical fiber was used to heat in-fiber Bragg gratings in order to alter the grating's optical response to surrounding media. The functional enhancement of optically heated Bragg gratings as sensor devices is demonstrated by a

Kevin P. Chen; Ben McMillen; Michael Buric; Chuck Jewart; Wei Xu

2005-01-01

382

Thermal and Structural Analysis of FIMS Grating  

Microsoft Academic Search

Far ultraviolet IMaging Spectrograph (FIMS) should be designed to maintain its structural stability and to minimize optical performance degradation in launch and in operation enviroments. The structural and thermal analyzes of grating and grating mount system, which are directly related to FIMS optical performance, was performed using finite element method. The grating mount was made to keep the grating stress

K.-I. Seon; I.-S. Yuk; K.-S. Ryu; J.-H. Park; K. Kang; H. Jin; U.-W. Nam; W. Han; K.-W. Min; W.-B. Lee; J. Edelstein; E. Korpela

2001-01-01

383

Measurements on the Zeeman-splitting of analytical lines by means of a continuum source graphite furnace atomic absorption spectrometer with a linear charge coupled device array  

Microsoft Academic Search

A spectrometer for time-resolved high-resolution spectroscopic measurements of line splittings in inverse Zeeman effect corrected atomic absorption spectrometry is presented. The system consists of a continuum source, a longitudinal Zeeman-THGA module, a high-resolution double echelle monochromator, and a linear CCD array. Splitting patterns of atomic lines in a magnetic field have been determined and are compared with theory. The continuum

U. Heitmann; M. Schutz; H. Beckerrob; S. Florek

1996-01-01

384

Tropospheric Emission Spectrometer and Airborne Emission Spectrometer  

NASA Technical Reports Server (NTRS)

The Tropospheric Emission Spectrometer (TES) is an instrument being developed for the NASA Earth Observing System Chemistry Platform. TES will measure the distribution of ozone and its precursors in the lower atmosphere. The Airborne Emission Spectrometer (AES) is an aircraft precursor to TES. Applicable descriptions are given of instrument design, technology challenges, implementation and operations for both.

Glavich, T.; Beer, R.

1996-01-01

385

High resolution extreme ultraviolet spectrometer for an electron beam ion trap  

SciTech Connect

An extreme ultraviolet spectrometer has been developed for spectroscopic studies of highly charged ions with an electron beam ion trap. It has a slit-less configuration with a spherical varied-line-spacing grating that provides a flat focal plane for grazing incidence light. Alternative use of two different gratings enables us to cover the wavelength range 1-25 nm. Test observations with the Tokyo electron beam ion trap demonstrate the high performance of the present spectrometer such as a resolving power of above 1000.

Ohashi, Hayato; Yatsurugi, Junji; Nakamura, Nobuyuki [Institute for Laser Science, University of Electro-Communications, Chofu, Tokyo 182-8585 (Japan); Sakaue, Hiroyuki A. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2011-08-15

386

[Small imaging spectrometer for the inspection of fruit quality].  

PubMed

Imaging spectrometer can acquire spatial and spectral information of the target at the same time, achieve high-precision, non-destructive, non-contamination and large area instantaneous inspection of the fruit. In order to get the imaging spectrum of the fruit, compact imaging spectrometer with convex grating produced by self was designed, it has the advantages of good performance, small volume and low weight, its resolution at 578 nm is 2.1 nm, and spectral line bend and chromatic distortion are both smaller than 0.6%. Laboratory test of the imaging spectrometer and the experiment of getting the imaging spectrum of apple were done, and the result shows that the imaging spectrometer satisfies the design requirement and can acquire the imaging spectrum of apple rapidly with high precision for inspection of fruit quality. PMID:22497177

Liu, Yu-juan; Tang, Yu-guo; Cui, Ji-cheng; Bayanheshig

2012-01-01

387

Coastal Research Imaging Spectrometer  

NASA Technical Reports Server (NTRS)

The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly. Both the visible and infrared subsystems scan in pushbroom mode: that is, an aircraft carrying the system moves along a ground track, the system is aimed downward, and image data are acquired in across-track linear arrays of pixels. Both subsystems operate at a frame rate of 30 Hz. The infrared and visible-light optics are adjusted so that both subsystems are aimed at the same moving swath, which has across-track angular width of 15 . Data from the infrared and visible imaging subsystems are stored in the same file along with aircraft- position data acquired by a Global Positioning System receiver. The combination of the three sets of data is used to construct infrared and hyperspectral maps of scanned areas (see figure). The visible subsystem is based on a grating spectrograph and a rapid-readout charge-coupled-device camera. Images of the swatch are acquired in 256 spectral bands at wavelengths from 400 to 800 nm. The infrared subsystem, which is sensitive in a single wavelength band of 8 to 10 m, is based on a focal-plane array of HgCdTe photodetectors that are cooled to an operating temperature of 77 K by use of a closed-Stirling-cycle mechanical cooler. The nonuniformities of the HgCdTe photodetector array are small enough that the raw pixel data from the infrared subsystem can be used to recognize temperature differences on the order of 1 C. By use of a built-in blackbody calibration source that can be switched into the field of view, one can obtain bias and gain offset terms for individual pixels, making it possible to offset the effects of nonuniformities sufficiently to enable the measurement of temperature differences as small as 0.1 C.

Lucey, Paul G.; Williams, Timothy; Horton, Keith A.

2004-01-01

388

Mars Airborne Prospecting Spectrometer  

NASA Astrophysics Data System (ADS)

One novel approach towards addressing the need for innovative instrumentation and investigation approaches is the integration of a suite of four spectrometer systems to form the Mars Airborne Prospecting Spectrometers (MAPS) for prospecting on Mars.

Steinkraus, J. M.; Wright, M. W.; Rheingans, B. E.; Steinkraus, D. E.; George, W. P.; Aljabri, A.; Hall, J. L.; Scott, D. C.

2012-06-01

389

[Current status and prospects of portable NIR spectrometer].  

PubMed

Near-infrared spectroscopy (NIRS) is a reliable, rapid, and non-destructive analytical method widely applied in as a number of fields such as agriculture, food, chemical and oil industry. In order to suit different applications, near-infrared spectrometers are now varied. Portable near-infrared spectrometers are needed for rapid on-site identification and analysis. Instruments of this kind are rugged, compact and easy to be transported. In this paper, the current states of portable near-infrared spectrometers are reviewed. Portable near-infrared spectrometers are built of different monochromator systems: filter, grating, Fourier-transform methods, acousto-optic tunable filter (AOTF) and a large number of new methods based on micro-electro-mechanical systems (MEMS). The first part focuses on working principles of different monochromator systems. Advantages and disadvantages of different systems are also briefly mentioned. Descriptions of each method are given in turn. Typical spectrometers of each kind are introduced, and some parameters of these instruments are listed. In the next part we discuss sampling adapters, display, power supply and some other parts, which are designed to make the spectrometer more portable and easier to use. In the end, the current states of portable near-infrared spectrometers are summarized. Future trends of development of portable near-infrared spectrometers in China and abroad are discussed. PMID:24555365

Yu, Xin-Yang; Lu, Qi-Peng; Gao, Hong-Zhi; Peng, Zhong-Qi

2013-11-01

390

Approaching ultimate resolution for soft x-ray spectrometers.  

PubMed

We explore the potential performance of soft x-ray spectrometers based on the use of varied-line-spacing spherical diffraction gratings (VLS-SG). The quantitative assessment is based on an optimization procedure to obtain both negligible optical aberrations at full illumination of the grating and a quasi linear focal curve. It involves high-order optical aberration cancellation to calculate the focal curves. We also examine the validity of small divergence closed-form formulas describing the light path function. Optimizing the optical and geometric parameters gives an ultimate resolving power, at 930 eV, of between 10,800 for a 3 m long instrument and 34,000 for an 11 m spectrometer according to the Rayleigh criterion. Typical fabrication tolerances would scale these values down by about 10%. The findings are validated by ray-tracing simulations. PMID:22781243

Chiuzb?ian, Sorin G; Hague, Coryn F; Lning, Jan

2012-07-10

391

A visible-infrared imaging spectrometer for planetary missions  

NASA Technical Reports Server (NTRS)

This final report summarizes the design effort for the construction of a visible-infrared imaging spectrometer for planetary missions, funded by NASA under the Planetary Instrument Definition and Development Program. The goal was to design and develop a prototype brassboard pushbroom imaging spectrometer covering the 0.35 gm to 2.5 gm spectral region using a simplified optical layout that would minimize the size, mass and parts count of the instrument by using a single holographic grating to disperse and focus light from a single slit onto both the infrared and visible focal plane arrays. Design approaches are presented and analyzed, along with problems encountered and recommended solutions to those problems. In particular, a new type of grating, incorporating two sets of rulings and a filter in a layered structure, is presented for further development.

McCord, Thomas (Principal Investigator); Voelker, Mark; Owensby, Pam; Warren, Cris; Mooradian, Greg

1996-01-01

392

ORFEUS focal plane instrumentation: The Berkeley spectrometer  

NASA Technical Reports Server (NTRS)

A spectrograph for the ORFEUS mission that incorporates four varied line-space, spherically figured diffraction gratings was designed. The ORFEUS, a 1-m normal incidence telescope is equipped with 2 focal plane spectrographs. The Berkeley spectrograph was developed with an optimizing raytracing computer code. Each grating accepts the light from 20 percent of the aperture of the telescope primary mirror and has a unique set of characteristics to cover a sub-bandpass within the 390 to 1200 A spectral range. Two photon-counting detectors incorporating a time delay readout system are used to record the spectra from all four gratings simultaneously. The nominal design achieves a spectral resolution (FWHM) in excess of 5500 at all wavelengths within the bandpass. The resolution is limited primarily by the detector spatial resolution. The 1 sigma astigmatism of this design varies between 13 and 150 micrometer on the same focal surface. An independent, direct imaging system tracks the drift of the target within the spectrometer aperture and allows measurement of the misalignment between the telescope optical axis and that of the external star tracker. The resolution and astigmatism achievable with this design are superior to those of a standard Rowland spectrograph designed with the same constraints.

Hurwitz, Mark; Bowyer, Stuart

1988-01-01

393

Grating profiles in dichromated gelatin  

Microsoft Academic Search

The modulation profiles of gratings recorded in dichromated gelatin are derived using a simple theory. The effects of nonlinear recording at high exposure levels and varying beam ratios are considered.

L. T. Blair; L. Solymar

1990-01-01

394

Fiber Grating Environmental Sensing System  

DOEpatents

Fiber grating environmental measurement systems are comprised of sensors that are configured to respond to changes in moisture or chemical content of the surrounding medium through the action of coatings and plates inducing strain that is measured. These sensors can also be used to monitor the interior of bonds for degradation due to aging, cracking, or chemical attack. Means to multiplex these sensors at high speed and with high sensitivity can be accomplished by using spectral filters placed to correspond to each fiber grating environmental sensor. By forming networks of spectral elements and using wavelength division multiplexing arrays of fiber grating sensors may be processed in a single fiber line allowing distributed high sensitivity, high bandwidth fiber optic grating environmental sensor systems to be realized.

Schulz, Whitten L. (Fairview, OR); Udd, Eric (Fairview, OR)

2003-07-29

395

Optical design of a coastal ocean imaging spectrometer.  

PubMed

We present an optical design for an airborne imaging spectrometer that addresses the unique constraints imposed by imaging the coastal ocean region. A fast (F/1.8) wide field system (36 degrees) with minimum polarization dependence and high response uniformity is required, that covers the spectral range 350-1050 nm with 3 nm sampling. We show how these requirements can be achieved with a two-mirror telescope and a compact Dyson spectrometer utilizing a polarization-insensitive diffraction grating. PMID:18545620

Mouroulis, Pantazis; Green, Robert O; Wilson, Daniel W

2008-06-01

396

[A two-dimensional double dispersed hadamard transform spectrometer].  

PubMed

A kind of two-dimensional hadamard transform spectrometer was developed. A grating was used for chromatic dispersion of orders and a prism was used for spectral dispersion. Quite different from traditional CCD detection method, a digital micromirror device (DMD) was applied for optical modulation, and a simple point detector was used as the sensor. Compared with traditional two-dimensional spectrometer, it has the advantage of high resolution and signal-noise-ratio, which was proved by theoretical calculation and computer simulation. PMID:22870674

Liu, Jia; Shi, Lei; Li, Kai; Zheng, Xin-Wen; Zeng, Li-Bo; Wu, Qiong-Shui

2012-06-01

397

Galileo Ultraviolet Spectrometer experiment  

Microsoft Academic Search

The Galileo ultraviolet spectrometer experiment uses data obtained by the Ultraviolet Spectrometer (UVS) mounted on the pointed orbiter scan platform and from the Extreme Ultraviolet Spectrometer (EUVS) mounted on the spinning part of the orbiter with the field of view perpendicular to the spin axis. The UVS is a Ebert-Fastie design that covers the range 113432 nm with a wavelength

C. W. Hord; A. I. F. Stewart; C. A. Barth; L. W. Esposito; G. E. Thomas; B. R. Sandel; D. M. Hunten; A. L. Broadfoot; D. E. Shemansky; J. M. Ajello; R. A. West

1992-01-01

398

Compact Two-Dimensional Spectrometer Optics  

NASA Technical Reports Server (NTRS)

The figure is a simplified depiction of a proposed spectrometer optical unit that would be suitable for incorporation into a remote-sensing instrumentation system. Relative to prior spectrometer optical assemblies, this unit would be compact and simple, largely by virtue of its predominantly two-dimensional character. The proposed unit would be a combination of two optical components. One component would be an arrayed-waveguide grating (AWG) an integrated-optics device, developed for use in wavelength multiplexing in telecommunications. The other component would be a diffraction grating superimposed on part of the AWG. The function of an AWG is conceptually simple. Input light propagates along a single-mode optical waveguide to a point where it is split to propagate along some number (N) of side-by-side waveguides. The lengths of the optical paths along these waveguides differ such that, considering the paths in a sequence proceeding across the array of waveguides, the path length increases linearly. These waveguides launch quasi-free-space waves into a planar waveguide-coupling region. The waves propagate through this region to interfere onto an array of output waveguides. Through proper choice of key design parameters (waveguide lengths, size and shape of the waveguide coupling region, and lateral distances between waveguides), one can cause the input light to be channeled into wavelength bins nominally corresponding to the output waveguides.

Hong, John

2008-01-01

399

MEMS Bragg grating force sensor.  

PubMed

We present modeling, design, fabrication and characterization of a new type of all-optical frequency modulated MEMS force sensor based on a mechanically amplified double clamped waveguide beam structure with integrated Bragg grating. The sensor is ideally suited for force measurements in harsh environments and for remote and distributed sensing and has a measured sensitivity of -14 nm/N, which is several times higher than what is obtained in conventional fiber Bragg grating force sensors. PMID:21996861

Reck, Kasper; Thomsen, Erik V; Hansen, Ole

2011-09-26

400

Phase gratings with subwavelength structures  

NASA Astrophysics Data System (ADS)

Polarization-selective gratings are designed by use of rigorous electromagnetic diffraction theory. The polarizing effects are attained by special surface-relief structures. We present a scheme for coding two different optical functions in one diffractive element. It is based on a combination of the scalar diffraction theory and the effective-medium theory. The diffractive element may be regarded as a combination of a phase element and a subwavelength grating. Copyright (c) 1995 Optical Society of America

Schmitz, Martin; Bruer, Ralf; Bryngdahl, Olof

1995-11-01

401

Durable silver thin film coating for diffraction gratings  

DOEpatents

A durable silver film thin film coated non-planar optical element has been developed to replace Gold as a material for fabricating such devices. Such a coating and resultant optical element has an increased efficiency and is resistant to tarnishing, can be easily stripped and re-deposited without modifying underlying grating structure, improves the throughput and power loading of short pulse compressor designs for ultra-fast laser systems, and can be utilized in variety of optical and spectrophotometric systems, particularly high-end spectrometers that require maximized efficiency.

Wolfe, Jesse D. (Discovery Bay, CA); Britten, Jerald A. (Oakley, CA); Komashko, Aleksey M. (San Diego, CA)

2006-05-30

402

Development of an ultra-high resolution diffraction grating forsoft x-rays  

SciTech Connect

Resonant Inelastic X-ray Scattering (RIXS) is the one of themost powerful methods for investigation of the electronic structure ofmaterials, specifically of excitations in correlated electron systems.However the potential of the RIXS technique has not been fully exploitedbecause conventional grating spectrometers have not been capable ofachieving the extreme resolving powers that RIXS can utilize. State ofthe art spectrometers in the soft x-ray energy range achieve ~;0.25 eVresolution, compared to the energy scales of soft excitations andsuperconducting gap openings down to a few meV. Development ofdiffraction gratings with super high resolving power is necessary tosolve this problem. In this paper we study the possibilities offabrication of gratings of resolving power of up to 106 for the 0.5 1.5KeV energy range. This energy range corresponds to all or most of theuseful dipole transitions for elements of interest in most correlatedelectronic systems, i.e., oxygen K-edge of relevance to all oxides, thetransition metal L2,3 edges, and the M4,5 edges of the rare earths.Various approaches based on different kinds of diffraction gratings suchas deep-etched multilayer gratings, and multilayer coated echelettes arediscussed. We also present simulations of diffraction efficiency for suchgratings, and investigate the necessary fabricationtolerances.

Voronov, Dmitriy L.; Cambie, Rossana; Feshchenko, Ruslan M.; Gullikson, Eric M.; Padmore, Howard A.; Vinogradov, Alexander V.; Yashchuk, Valeriy V.

2007-08-21

403

A Compact, Fast, Wide-Field Imaging Spectrometer System  

NASA Technical Reports Server (NTRS)

We present test results from a compact, fast (F/1.4) imaging spectrometer system with a 33 degree field of view, operating in the 450-1650 nm wavelength region with an extended response InGaAs detector array. The system incorporates a simple two-mirror telescope and a steeply concave bilinear groove diffraction grating made with gray scale x-ray lithography techniques. High degree of spectral and spatial uniformity (97%) is achieved.

Mouroulis, Pantazis; VanGorp, Byron E.; White, Victor E.; Mumolo, Jason M.; Hebert, Daniel; Feldman, Martin

2011-01-01

404

A compact, fast, wide-field imaging spectrometer system  

NASA Astrophysics Data System (ADS)

We present test results from a compact, fast (F/1.4) imaging spectrometer system with a 33 field of view, operating in the 450-1650 nm wavelength region with an extended response InGaAs detector array. The system incorporates a simple two-mirror telescope and a steeply concave bilinear groove diffraction grating made with gray scale x-ray lithography techniques. High degree of spectral and spatial uniformity (97%) is achieved.

Mouroulis, Pantazis; Van Gorp, Byron E.; White, Victor E.; Mumolo, Jason M.; Hebert, Daniel; Feldman, Martin

2011-06-01

405

Happy New Year 2004 from SSX-FRC! I guess the big news from 2003 is that our regular DOE grant (that  

E-print Network

. The McPherson spectrometer will be used with a 316 g/mm echelle grating blazed for at 5664 nm to achieve phase of operation. The centerpiece in the next phase is a new ion doppler spectrometer that Chris) spectrometer for use in an ion doppler spectroscopy system on SSX. This purchase was made through our main DOE

Brown, Michael R.

406

Off-plane anastigmatic imaging in Offner spectrometers.  

PubMed

In this paper, the imaging performance of an Offner concentric imaging spectrometer is analyzed when the spectrometer entrance slit is disposed arbitrarily on the plane that is parallel to the grating grooves and contains the common center of curvature. Astigmatism-corrected designs are obtained for off-plane incidence on the grating if one point on the slit is located on the Rowland circle of the primary mirror. In this case, the combined system of primary mirror plus diffraction grating provides two astigmatic line images oriented parallel and orthogonal to the plane of diffraction, with the former located on the same plane as the slit. Consequently, these images can be brought to a single focus on this plane by the tertiary mirror if its radius of curvature is chosen properly. In addition, coma aberration is simultaneously removed. These results can be applied to the design of two-mirror or three-mirror spectrometers, generalizing the concept of the best imaging circle and providing solutions to get anastigmatic imaging for two object points and two wavelengths. PMID:22048301

Prieto-Blanco, Xess; Gonzlez-Nuez, Hctor; de la Fuente, Ral

2011-11-01

407

Diffraction gratings for optical sensing  

NASA Astrophysics Data System (ADS)

The following document summarizes a journey through the world of diffraction gratings, covering topics such as their history, fabrication, metrology, and uses in some of the most precise scientific experiments ever proposed. Though diffraction gratings have long been used for spectroscopy and pulse compression, it was not until recently that researchers have explored their ability to split and recombine single-frequency CW laser sources for high-precision interferometry. Gravitational-wave detection, one of the most challenging sensing applications to date, is being investigated by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Laser Interferometer Space Antenna (LISA) projects. Future generations of LIGO and LISA detectors may incorporate gratings as key optical components. This thesis describes the ways gratings can improve interferometer performance by simplifying thermal management and discusses the essential challenges that must be overcome before they can be adopted. The use of gratings requires new interferometer geometries. We show cases where these can be implemented simply and compactly. Gravitational-wave interferometry imposes many requirements on grating components. Using improved metrology methods, we demonstrate that large dielectric gratings with uniformly high efficiency can be fabricated and validated. In particular, we measure the diffraction efficiency of two 20-cm-scale gratings over their entire apertures. The values taken from across their surfaces collectively had means and standard deviations of mu = 99.293% and sigma = 0.164%, and mu =99.084% and sigma =0.079%. We also present simplified models of thermal distortions in gratings, and show them to be in good agreement with measurements conducted by a wavefront sensor. Special focus is given to experimental demonstrations that have achieved highly precise measurements of translational and rotational motion, also known as displacement and angular sensing. For the former, resonant-cavity methods that have achieved both high sensitivity and high dynamic range (10 pm/?Hz at 1 Hz over 620 nm) are described. For the latter, a novel device known as the grating angular sensor that has achieved a sensitivity level of 0.2 nrad/?Hz at 1 kHz is presented.

Lu, Patrick P.

408

Monitoring of Laser Material Welding Process Using UV-Visible Spectrometer  

SciTech Connect

UV-Visible spectrometer is used to record emission from magnesium and titanium metal plates during laser welding processing. Geometrically corrected Czerny-Turner configurations nearly eliminate defocusing problem. The Optikwerks software is used to find the optimum Czerny-Turner configuration and to choose optical elements such as grating types, mirrors focal length and diameter, and slit width. The design parameters of the uv-visible spectrometer in the wavelength range 200-1100 nm for monitoring laser material welding processing.

Genc, B.; Kacar, E.; Akman, E.; Demir, A. [University of Kocaeli, Laser Technologies Research and Application Center, Kocaeli (Turkey)

2007-04-23

409

On-chip spectrometer with a circular-hole defect for optical sensing applications.  

PubMed

We propose an optical sensor by integrating a circular-hole defect with an etched diffraction grating spectrometer based on amorphous silicon photonic platforms. There are some superiorities of this device, such as high sensitivity (~10000 nm/RIU), and ability to deliver component analysis from the near-infrared spectrum by using the integrated spectrometer. As application example, the chip is used for distinguishing similar biodiesel types and accurately determining their concentrations in a diesel oil mixture. PMID:23038564

Song, Jun; Zhou, Xiang; Li, Yuan-zhou; Li, Xuan

2012-08-13

410

Ray tracing method for the grazing incidence flat-field imaging soft X-ray spectrometer  

NASA Astrophysics Data System (ADS)

A ray tracing method is introduced for helping adjustment and spectra analysis of the grazing incidence flat-field imaging soft X-ray spectrometer. For a single point source, the spectra images obtained by separate components, the toroidal mirror, and the grazing incidence flat-field concave grating with varied line spaces are given respectively. The calculated spectral images of the single point source by the spectrometer are also given for comparison with measurements with different experimental alignments.

Dong, Quan-Li; Liu, Yun-Quan; Teng, Hao; Li, Ying-Jun; Zhang, Jie

2014-06-01

411

Holographic Gratings for Optical Processing  

NASA Technical Reports Server (NTRS)

Investigation of astronomical objects and tracking of man-made space objects lead to generation of huge amount of information for optical processing. Traditional big-size optical elements (such as optical telescopes) have a tendency for increasing aperture size in order to improve sensitivity. This tendency leads to increasing of weight and costs of optical systems and stimulate search for the new, more adequate technologies. One approach to meet these demands is based on developing of holographic optical elements using new polymeric materials. We have investigated possibility to use new material PQ-PMMA (phenantrenequinone-doped PMMA (Polymethyl Methacrylate)) for fabrication of highly selective optical filters and fast spatial-temporal light modulators. This material was originally developed in Russia and later was tested in CalTech as a candidate material for optical storage. Our theoretical investigation predicts the possibility of realization of fast spatial and temporal light modulation, using volume reflection-type spectral filter. We have developed also model of holographic-grating recording in PQ-PMMA material, based on diffusional amplification. This mechanism of recording allow to receive high diffraction efficiency during recording of reflection-type volume holographic grating (holographic mirror). We also investigated recording of dynamic gratings in the photorefractive crystals LiNbO3 (LN) for space-based spectroscopy and for adaptive correction of aberrations in the telescope's mirrors. We have shown, that specific 'photogalvanic' mechanism of holographic grating recording in LN allow to realize recording of blazed gratings for volume and surface gratings. Possible applications of dynamic gratings in LN for amplification of images, transmitted through an imaging fiber guide was also demonstrated.

Kukhtarev, Nickolai

2002-01-01

412

First results from a next-generation off-plane X-ray diffraction grating  

NASA Astrophysics Data System (ADS)

Future NASA X-ray spectroscopy missions will require high throughput, high resolving power grating spectrometers. Off-plane reflection gratings are capable of meeting the performance requirements needed to realize the scientific goals of these missions. We have identified a novel grating fabrication method that utilizes common lithographic and microfabrication techniques to produce the high fidelity groove profile necessary to achieve this performance. Application of this process has produced an initial pre-master that exhibits a radial (variable line spacing along the groove dimension), high density (> 6000 grooves/mm), laminar profile. This pre-master has been tested for diffraction efficiency at the BESSY II synchrotron light facility and diffracts up to 55 % of incident light into usable spectral orders. Furthermore, tests of spectral resolving power show that these gratings are capable of obtaining resolving powers well above 1300 ( ?/? ?) with limitations due to the test apparatus, not the gratings. Obtaining these results has provided confidence that this fabrication process is capable of producing off-plane reflection gratings for the next generation of X-ray observatories.

McEntaffer, Randall; DeRoo, Casey; Schultz, Ted; Gantner, Brennan; Tutt, James; Holland, Andrew; O'Dell, Stephen; Gaskin, Jessica; Kolodziejczak, Jeffrey; Zhang, William W.; Chan, Kai-Wing; Biskach, Michael; McClelland, Ryan; Iazikov, Dmitri; Wang, Xinpeng; Koecher, Larry

2013-08-01

413

Osmium coated diffraction grating in the Space Shuttle environment - Performance  

NASA Technical Reports Server (NTRS)

Samples coated with osmium were flown on the early Shuttle test flights, and on the return of these samples, the osmium coating was found to have disappeared, evidently due to the oxidation of the material in the atomic oxygen atmosphere. An instrument flown on the Spacelab 1 mission comprised an array of five spectrometers covering the extreme ultraviolet (EUV) to near-IR wavelengths. The EUV spectrometer contained an osmium-coated reflective grating located fairly deep within the instruments. Here, results of an assessment of the reflectivity and stability of the osmium surface over the course of the ten-day mission are reported. It is concluded that the osmium reflective coating remained stable relative to the spectrometer coated with MgF2 over the course of the mission. In addition, the ratio of sensitivity of these two spectrometers did not change in any major way from the time of the laboratory calibration until the time of flight two years later. Any changes are within the 50-percent calibration uncertainty.

Torr, M. R.

1985-01-01

414

Sampled chirped fiber gratings as distributed pressure sensors  

Microsoft Academic Search

Fiber gratings have been studied for their applications in sensing and communications. Many sensing applications of the uniform fiber Bragg grating, chirped fiber grating and long period grating have been studied, proposed and commercialized. Sampled chirped gratings have been studied for multichannel dispersion compensation in DWDM systems. In this paper, we show that the sampled chirped fiber grating can be

Swee Chuan Tjin; Lipi Mohanty; Nam Quoc Ngo

2004-01-01

415

Sampled chirped fiber gratings as distributed pressure sensors  

Microsoft Academic Search

Fiber gratings have been studied for their applications in sensing and communications. Many sensing applications of the uniform fiber Bragg grating, chirped fiber grating and long period grating have been studied, proposed and commercialized. Sampled chirped gratings have been studied for multichannel dispersion compensation in DWDM systems. In this paper, we show that the sampled chi rped fiber grating can

Swee Chuan Tjin; Lipi Mohanty; Nam Quoc Ngo

416

Fabrication of extremely smooth blazed diffraction gratings  

E-print Network

High efficiency diffraction gratings are important in a variety of applications, such as optical telecommunications, lithography, and spectroscopy. Special interest has been placed on blazed diffraction gratings for their ...

Chang, Chih-Hao, 1980-

2004-01-01

417

Terahertz surface plasmon on chirped groove grating  

Microsoft Academic Search

The excitation of terahertz surface plasmon on metallized chirped groove gratings is studied in time- and frequency-domain. These gratings have a potential to launch and decouple broadband terahertz surface plasmon necessary for integrated optical circuits.

M. Martl; J. Darmo; K. Unterrainer; E. Gornik

2008-01-01

418

Chirped fiber-optic Bragg grating interrogator in a multiplexed Bragg grating sensor configuration  

Microsoft Academic Search

This paper presents a chirped grating interrogator for fiber Bragg grating sensors. The interrogator uses the wavelength dependence of the phase group-delay response of a chirped fiber Bragg grating to determine the Bragg wavelength of the sensor. The sensitivity of the interrogator is determined by the selection of the grating length and the bandwidth. The experimental results demonstrated strain measurements

Anatoli A. Chtcherbakov; Pieter L. Swart

2004-01-01

419

Pseudoheterodyne demodulation technique for fiber Bragg grating sensors using two matched gratings  

Microsoft Academic Search

A pseudoheterodyne, open-loop demodulation technique for detecting wavelength shifts in wavelength encoded fiber Bragg grating sensors is presented. The scheme uses a processing Bragg grating that is identical to one used as a sensor. When the processing fiber grating is stretched periodically, the system of two gratings produces a carrier at this frequency with its phase modulated by the measurand

L. A. Ferreira; J. L. Santos; F. Farahi

1997-01-01

420

Application of Diffraction Grating Theory to Analysis and Fabrication of Waveguide Gratings  

Microsoft Academic Search

This dissertation includes three separate studies of related waveguide grating phenomena. These studies deal with a numerical improvement of the integral method of diffraction grating theory, the theoretical analysis of waveguide gratings, and fabrication techniques for photoresist grating masks. The first topic addresses the acceleration of the convergence of the integral kernels. To improve the performance of the integral method

Lifeng Li

1988-01-01

421

A high-throughput, high-resolution spectrometer for mapping the heliopause and 3-D Solar Wind using He+ 30.4nm  

E-print Network

A high-throughput, high-resolution spectrometer for mapping the heliopause and 3-D Solar Wind using Entrance slit farm with ~ 1000 slits Photon counting imager Concave grating used near normal incidence Rowland mount spectrometer with improvements for high throughput 1. Entrance slit => 1-D coded aperture 2

California at Berkeley, University of

422

Design of camera and spectrometer dual-use system  

NASA Astrophysics Data System (ADS)

Imaging spectrometers based on prism-grating-prism (PGP) have advantage of direct vision, as a basis for the design of an optical system for a spectrometer and camera dual-use, the system can plug the light splitting element to switch between the spectrometer and camera. This paper has discussed the working principles and structure of the PGP and spectrometer, collimating and focusing lens design principles, then the design result has been presented. The spectral range of the system is 400-800nm, the pixel size of CCD used is 10um 10um, 1010 1018 pixels, the object space numerical aperture is 0.1. In order to reduce the cost and eliminate aberration, collimating lens and focusing lens have symmetric structure, in order to improve the diffraction efficiency, PGP uses the volume phase holographic transmission grating. After optimization the design by ZEMAX software, the whole spectral range resolution is better than 1nm in average, the MTF at Nyquist frequency is greater than 0.7, the length of the whole system is 87mm.

Qi, Yong-hong; Xue, Bin; Zhao, Yi-yi; Tao, Jin-you

2013-08-01

423

Grating polarizers in waveguide miter bends  

NASA Astrophysics Data System (ADS)

Rectangular grooved gratings have been fabricated on mirrors of waveguide miter bends. When the HE11 mode was propagated in corrugated waveguide with diameter equal to approximately 12 wavelengths, these gratings performed in the same manner as predicted using plane wave theory. Two gratings with different groove depths in successive miter bends are sufficient to generate a rather wide range of polarizations. These gratings are particularly convenient in waveguide, which offers ease of alignment, compact transverse dimensions, and the possibility of vacuum operation.

Doane, John L.

1992-11-01

424

Analysis of the focal pattern distortion of a cylindrical concave micro-grating in a slab waveguide and the mechanism of spatial resolution recovery  

NASA Astrophysics Data System (ADS)

With modern lithographic technology, a compact spectrometer is designed to include a blazed micro-grating with cylindrical concave grating profile. In order to restrict the sagittal beam divergence and to reduce the size of the spectrometer, the micro-grating is embedded inside a pair of planar mirrors used as a slab waveguide. In the simulations for the effect of the waveguide, we discover that the focal pattern distortion introduced by the waveguide causes a blunted and side-tailed peak in the spectrum. The distortion can be managed by allowing some gap between the edge of the waveguide and the image sensor. Such a configuration has greatly improved the resolving power of the micro-grating in this compact system.

Ko, Cheng-Hao; Lin, Jian-Shian; Chen, Nien-Po; Chen, Chang-Tai; Shen, Ji-Lin

2010-01-01

425

[Study on an optical system of small ultraviolet imaging spectrometer with high resolution in broadband].  

PubMed

An ultraviolet imaging spectrometer was studied based on the principle of the small scale ultraviolet spectral instrument. The scheme composed of an off-axis parabolic mirror telescope and a single toroidal grating spectral imaging system was designed. The optimization of the optical system is the optimum processing for the parameters of the toroidal grating. The optical path function and the aberration equations of the grating were analyzed. The perfect anastigmatism conditions and imaging conditions of the single toroidal grating system were obtained. These two conditions that cannot be satisfied by the algebra calculation method limit the field of view and waveband of the spectrometer. The genetic algorithm was introduced to solve the problem. A solar-blind ultraviolet imaging spectrometer for 200-280 nm was designed to verify the design method. The optimum initial configuration was calculated and simulated. A system with F/# 5.7, focal length 102 mm and high spatial resolution was designed. The modulation transfer functions (MTF) of all fields of view are more than 0.65 in the waveband in the required Nyquist frequency (20 1p x mm(-1)). The design results indicate that the optical system theory can be applied to the small scale ultraviolet imaging spectrometer with high resolution and spectral broadband. PMID:23697155

Cong, Hai-Fang; Wang, Chun-Hui; Wang, Yu

2013-02-01

426

Design of imaging spectrometer based on Czerny-Turner in FUV  

Microsoft Academic Search

It is the astigmatism that leads the traditional imaging spectrometer based on Czerny-Turner to have low spatial resolution. And it is discovered that when the distance between concave mirror and grating, x, is equal to the twice of focal length, ?, of the mirror, SII = SIII = 0 and the aberration is the least as well as the astigmatism

Jianpeng Liu; Yi Tang; Yan Wu; Zhige Zhang; Guoqiang Ni

2010-01-01

427

Subaru IR Echelle Spectroscopy of Herbig-Haro Driving Sources. I. H2 and [Fe II] Emission  

Microsoft Academic Search

We present infrared echelle spectroscopy of three Herbig-Haro (HH) driving sources (SVS 13, B5-IRS 1, and HH 34 IRS) using Subaru IRCS. The large diameter of the telescope and wide spectral coverage of the spectrograph allowed us to detect several H2 and [Fe II] lines in the H and K bands. These include H2 lines arising from v=1-3 and J=1-11,

M. Takami; A. Chrysostomou; T. P. Ray; C. J. Davis; W. R. F. Dent; J. Bailey; M. Tamura; H. Terada; T. S. Pyo

2006-01-01

428

Near-IR echelle spectroscopy of Class I protostars: Mapping Forbidden Emission-Line (FEL) regions in [FeII  

Microsoft Academic Search

Near-IR echelle spectra in [FeII] 1.644 mu m emission trace Forbidden Emission Line (FEL) regions towards seven Class I HH energy sources (SVS 13, B5-IRS1, IRAS 04239+2436, L1551-IRS5, HH 34-IRS, HH 72-IRS and HH 379-IRS) and three classical T Tauri stars (AS 353A, DG Tau and RW Aur). The parameters of these FEL regions are compared to the characteristics of

C. J. Davis; E. Whelan; T. P. Ray; A. Chrysostomou

2003-01-01

429

A geostationary imaging spectrometer TOMS instrument  

NASA Technical Reports Server (NTRS)

One design for a geostationary Total Ozone Mapping Spectrometer (TOMS) with many desirable features is an imaging spectrometer. A preliminary study makes use of a 0.25 m Czerny-Turner spectrometer with which the Earth is imaged on a charge-coupled device (CCD) in dispersed light. The wavelength is determined by a movable grating which can be set arbitrarily by ground control. The signal integration time depends on wavelength but this system allows arbitrary timing by command. Special circumstances such as a requirement to track a low-lying sulfur dioxide cloud or a need to discriminate high level ozone from total ozone at midlatitudes could be obtained by adding a particular wavelength to the normally pre-programmed time sequence. The incident solar irradiance is measured by deploying a diffuser plate in the field of view. Individual detector elements correspond to scene elements in which the several wavelengths are serially sampled and the Earth radiance is compared to the incident sunlight. Thus the problem of uncorrelated drift of multiple detectors is removed.

Krueger, Arlin J.; Maloy, J. Owen; Roeder, H. B.

1987-01-01

430

Multiplexing of fiber optic Bragg grating sensors  

Microsoft Academic Search

The main objective of this project was to develop a novel technique for multiplexing fiber Bragg grating sensors for strain measurements. Multiplexing is a very important issue for fiber Bragg grating sensors, as it allows them to be used for distributed sensing where their greatest impact is anticipated. Three types of multiplexed fiber Bragg grating sensor system prototypes were developed

Kok Cheung Peter Chan

2000-01-01

431

Electromagnetic Absorption by Metamaterial Grating System  

Microsoft Academic Search

Total absorption of electromagnetic waves is demonstrated in a system composed of zero-order metamaterial grating and rearward metamaterial wall. The grating and the wall are separated by an air gap. Two mechanisms are shown to account for this absorption. The flrst one is due to the existence of standing waves in both the grooves of the grating and the air

Xiaobing Cai; Gengkai Hu

2008-01-01

432

Diffraction gratings used as identifying markers  

DOEpatents

A finely detailed defraction grating is applied to an object as an identifier or tag which is unambiguous, difficult to duplicate, or remove and transfer to another item, and can be read and compared with prior readings with relative ease. The exact pattern of the defraction grating is mapped by diffraction moire techniques and recorded for comparison with future readings of the same grating.

Deason, Vance A. (Idaho Falls, ID); Ward, Michael B. (Idaho Falls, ID)

1991-01-01

433

Grating polarizers in waveguide miter bends  

Microsoft Academic Search

Rectangular grooved gratings have been fabricated on mirrors of waveguide miter bends. When the HE11 mode was propagated in corrugated waveguide with diameter equal to approximately 12 wavelengths, these gratings performed in the same manner as predicted using plane wave theory. Two gratings with different groove depths in successive miter bends are sufficient to generate a rather wide range of

John L. Doane; General Atomics

1992-01-01

434

HiJaK: the high-resolution J, H and K spectrometer  

NASA Astrophysics Data System (ADS)

We present the science drivers, design requirements and a preliminary design for a high-resolution, broad- bandwidth, slit-fed cross-dispersed near-infrared spectrometer for 5-meter-class telescopes. Our concept, called the High-Resolution J, H and K Spectrometer, or HiJaK, utilizes an R6 echelle in a white-pupil design to achieve high resolution in a compact configuration with a 2048 x 2048 pixel infrared detector. We present a preliminary ray-traced optical design matched to the new 4.3-meter Discovery Channel Telescope in Happy Jack, Arizona. We also discuss mechanical and cryogenic options to house our optical design.

Muirhead, Philip S.; Hall, Zachary J.; Veyette, Mark J.

2014-08-01

435

Sub-wavelength GaN-based membrane high contrast grating reflectors.  

PubMed

The GaN-based membrane high contrast grating (HCG) reflectors have been fabricated and investigated. The structural parameters including grating periods, grating height, filling factors and air-gap height were calculated to realize high reflectivity spectra with broad bandwidth by the rigorous coupled-wave analysis and finite-difference time-domain method. Based on the optimized simulation results, the GaN-based membrane HCGs were fabricated by e-beam lithography and focused-ion beam process. The fabricated GaN-based membrane HCG reflectors revealed high reflectivity at 460 nm band with large stopband width of 60 nm in the TE polarization measured by using the micro-reflectivity spectrometer. The experimental results also showed a good agreement with simulated ones. We believe this study will be helpful for development of the GaN-based novel light emitting devices in the blue or UV region. PMID:23037102

Wu, Tzeng Tsong; Syu, Yu Cheng; Wu, Shu Hsien; Chen, Wei Ting; Lu, Tien Chang; Wang, Shing Chung; Chiang, Hai Pang; Tsai, Din Ping

2012-08-27

436

A search for lithium in Pleiades brown dwarf candidates using the Keck hires echelle  

NASA Technical Reports Server (NTRS)

We report Keck Observatory high-resolution echelle spectra of lithium at 670.8 nm in two of the lowest luminosity brown dwarf candidates in the Pleiades. These objects have estimated masses of 0.055 to 0.059 solar mass from their location on a color-magnitude diagram relative to theoretical isochrones. Stellar interior models predict that Li has not burned in them. However, we find no evidence of the Li line, at limits 100 to 1000 times below the initial abundance. This indicates that Li has in fact been depleted, presumably by nuclear processing as occurs in Pleiades stars. Interior models suggest that such large Li depletion occurs only for objects with M greater than 0.09 solar mass at the age of the Pleiades. Thus, it is unlikely that the candidates are brown dwarfs. The brown dwarf candidates present a conflict: either they have masses greater than suggested from their placement on the H-R diagram, or they do have the very low suggested masses but are nonetheless capable of destroying Li, in only 70 Myr. Until this dilemma is resolved, the photometric identification of brown dwarfs will remain difficult. Resolution may reside in higher T(sub eff) derived from optical and IR colors or in lower T(sub eff) in the interior models.

Marcy, Geoffrey W.; Basri, Gibor; Graham, James R.

1994-01-01

437

StarCAT: A CATALOG OF SPACE TELESCOPE IMAGING SPECTROGRAPH ULTRAVIOLET ECHELLE SPECTRA OF STARS  

SciTech Connect

StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as 'stars', recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2 Ms. For many of the objects, broad ultraviolet coverage has been achieved by splicing echellegrams taken in two or more FUV (1150-1700 A) and/or NUV (1600-3100 A) settings. In cases of multiple pointings on conspicuously variable sources, spectra were separated into independent epochs. Otherwise, different epochs were combined to enhance the signal-to-noise ratio (S/N). A post-facto correction to the calstis pipeline data sets compensated for subtle wavelength distortions identified in a previous study of the STIS calibration lamps. An internal 'fluxing' procedure yielded coherent spectral energy distributions (SEDs) for objects with broadly overlapping wavelength coverage. The best StarCAT material achieves 300 m s{sup -1} internal velocity precision; absolute accuracy at the 1 km s{sup -1} level; photometric accuracy of order 4%; and relative flux precision several times better (limited mainly by knowledge of SEDs of UV standard stars). While StarCAT represents a milestone in the large-scale post-processing of STIS echellegrams, a number of potential improvements in the underlying 'final' pipeline are identified.

Ayres, Thomas R. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States)], E-mail: Thomas.Ayres@Colorado.edu

2010-03-01

438

Grazing-incidence spectrometer on the SSPX spheromak  

SciTech Connect

The Silver Flat Field Spectrometer (SFFS) is a high-resolution grazing-incidence diagnostic for magnetically confined plasmas. It covers the wavelength range of 25-450 {angstrom} with a resolution of {Delta}{lambda} = 0.3 {angstrom} FWHM. The SFFS employs a spherical 1200 lines/mm grating for flat-field focusing. The imaging is done using a back-illuminated Photometrics CCD camera allowing a bandwidth of around 200 {angstrom} per spectrum. The spectrometer has been used for atomic spectroscopy on electron beam ion traps and for plasma spectroscopy on magnetic confinement devices. The design of the SFFS and the spectrometer setup at the Sustained Spheromak Physics Experiment (SSPX) in Livermore will be presented.

Clementson, J; Beiersdorfer, P; Magee, E W

2008-05-02

439

Calibration of a high resolution grating soft x-ray spectrometera)  

NASA Astrophysics Data System (ADS)

The calibration of the soft x-ray spectral response of a large radius of curvature, high resolution grating spectrometer (HRGS) with a back-illuminated charge-coupled device detector is reported. The instrument is cross-calibrated for the 10-50 waveband at the Lawrence Livermore National Laboratory electron beam ion trap (EBIT) x-ray source with the EBIT calorimeter spectrometer. The HRGS instrument is designed for laser-produced plasma experiments and is important for making high dynamic range measurements of line intensities, line shapes, and x-ray sources.

Magee, E. W.; Dunn, J.; Brown, G. V.; Cone, K. V.; Park, J.; Porter, F. S.; Kilbourne, C. A.; Kelley, R. L.; Beiersdorfer, P.

2010-10-01

440

Modified Schwarzschild imaging spectrometer with a low F-number and a long slit.  

PubMed

A modified Schwarzschild imaging spectrometer utilizing three nonconcentric aspheric mirrors and a plane grating is designed that can handle low F-number, long slit, and broad spectral range. Based on the geometrical aberration theory and Rowland circle condition, the astigmatism-correcting method of the Schwarzschild imaging spectrometer is analyzed. The design procedure of initial parameters is programmed using Matlab software. As an example, a modified Schwarzschild imaging spectrometer operating in 400-1000 nm waveband with F-number of 2.5 and slit length of 13 mm is designed, and good imaging quality is obtained. PMID:24085210

Xue, Qingsheng

2013-10-01

441

A Fourier transform spectrometer for visible and near ultra-violet measurements of atmospheric absorption  

NASA Technical Reports Server (NTRS)

The development of a prototype, ground-based, Sun-pointed Michelson interferometric spectrometer is described. Its intended use is to measure the atmospheric amount of various gases which absorb in the near-infrared, visible, and near-ultraviolet portions of the electromagnetic spectrum. Preliminary spectra which contain the alpha, 0.8 micrometer, and rho sigma tau water vapor absorption bands in the near-infrared are presented to indicate the present capability of the system. Ultimately, the spectrometer can be used to explore the feasible applications of Fourier transform spectroscopy in the ultraviolet where grating spectrometers were used exclusively.

Parsons, C. L.; Gerlach, J. C.; Whitehurst, M.

1982-01-01

442

Experimental Studies of Photoresist Gratings.  

National Technical Information Service (NTIS)

Recently a new technique of making photoresist masks by simultaneous exposure and development (SED) of a positive photoresist was proposed. This new technique has been applied to making gratings with shipley AZ-1350J in the submicrometer-period range. Exc...

W. T. Tsang, S. Wang

1974-01-01

443

Holographic Grating Study. Volume 1.  

National Technical Information Service (NTIS)

The two primary goals of the study were to demonstrate the feasibility of fabricating low and high-efficiency ion-machined holographic gratings and, by means of optical analysis, to establish their suitability for use in practical high-energy laser system...

J. O. Garvey, R. J. Withrington, O. G. Ramer, A. A. Livanos, A. C. Livanos

1979-01-01

444

Electromagnetically induced grating with maximal atomic coherence  

SciTech Connect

We describe theoretically an atomic diffraction grating that combines an electromagnetically induced grating with a coherence grating in a double-{Lambda} atomic system. With the atom in a condition of maximal coherence between its lower levels, the combined gratings simultaneously diffract both the incident probe beam as well as the signal beam generated through four-wave mixing. A special feature of the atomic grating is that it will diffract any beam resonantly tuned to any excited state of the atom accessible by a dipole transition from its ground state.

Carvalho, Silvania A.; Araujo, Luis E. E. de [Instituto de Fisica ''Gleb Wataghin'', Universidade Estadual de Campinas, Campinas-SP, 13083-859 Sao Paulo (Brazil)

2011-10-15

445

One-dimensional space resolving flat-field holographic grating soft x-ray framing camera spectrograph for laser plasma diagnostics  

SciTech Connect

A 1D space resolving x-ray spectrum diagnostic system has been developed to study the radiation opacity of hot plasma on SG-II laser facility. The diagnostic system consists of a 2400 lines/mm flat-field holographic grating and a gated microchannel plate coupled with an optical CCD and covers the wavelength range of 5-50 A. The holographic grating was compared with a ruled one by measuring the emission spectra from a laser-produced molybdenum plasma. The results indicate that the holographic grating possesses better sensitivity than the ruled grating having nearly similar spectral resolution. The spectrograph has been used in radiative opacity measurement of Fe plasma. Simultaneous measurements of the backlight source and the transmission spectrum in appointed time range in one shot have been accomplished successfully with the holographic grating spectrometer. The 2p-3d transition absorption of Fe plasma near 15.5A in has been observed clearly.

Xiong Gang; Hu Zhimin; Li Hang; Zhao Yang; Shang Wanli; Zhu Tuo; Wei Minxi; Yang Guohong; Zhang Jiyan; Yang Jiamin [Research Center of Laser Fusion, China Academy of Engineering Physics, P.O. Box 919-986, Mianyang 621900 (China)

2011-04-15

446

Optical apparatus for forming correlation spectrometers and optical processors  

DOEpatents

Optical apparatus is disclosed for forming correlation spectrometers and optical processors. The optical apparatus comprises one or more diffractive optical elements formed on a substrate for receiving light from a source and processing the incident light. The optical apparatus includes an addressing element for alternately addressing each diffractive optical element thereof to produce for one unit of time a first correlation with the incident light, and to produce for a different unit of time a second correlation with the incident light that is different from the first correlation. In preferred embodiments of the invention, the optical apparatus is in the form of a correlation spectrometer; and in other embodiments, the apparatus is in the form of an optical processor. In some embodiments, the optical apparatus comprises a plurality of diffractive optical elements on a common substrate for forming first and second gratings that alternately intercept the incident light for different units of time. In other embodiments, the optical apparatus includes an electrically-programmable diffraction grating that may be alternately switched between a plurality of grating states thereof for processing the incident light. The optical apparatus may be formed, at least in part, by a micromachining process. 24 figs.

Butler, M.A.; Ricco, A.J.; Sinclair, M.B.; Senturia, S.D.

1999-05-18

447

Optical apparatus for forming correlation spectrometers and optical processors  

DOEpatents

Optical apparatus for forming correlation spectrometers and optical processors. The optical apparatus comprises one or more diffractive optical elements formed on a substrate for receiving light from a source and processing the incident light. The optical apparatus includes an addressing element for alternately addressing each diffractive optical element thereof to produce for one unit of time a first correlation with the incident light, and to produce for a different unit of time a second correlation with the incident light that is different from the first correlation. In preferred embodiments of the invention, the optical apparatus is in the form of a correlation spectrometer; and in other embodiments, the apparatus is in the form of an optical processor. In some embodiments, the optical apparatus comprises a plurality of diffractive optical elements on a common substrate for forming first and second gratings that alternately intercept the incident light for different units of time. In other embodiments, the optical apparatus includes an electrically-programmable diffraction grating that may be alternately switched between a plurality of grating states thereof for processing the incident light. The optical apparatus may be formed, at least in part, by a micromachining process.

Butler, Michael A. (Albuquerque, NM); Ricco, Antonio J. (Albuquerque, NM); Sinclair, Michael B. (Albuquerque, NM); Senturia, Stephen D. (Brookline, MA)

1999-01-01

448

A cryogenically cooled, multidetector spectrometer for infrared astronomy  

NASA Technical Reports Server (NTRS)

A liquid helium-cooled, 24 detector grating spectrometer was developed and used for low resolution astronomical observations in the 5 to 14 micron spectral range. The instrument operated on the 91 cm Kuiper Airborne Observatory, the 3 m IRTF (Mauna Kea), the 3 m Shane telescope (Lick Observatory), and the 152 cm NASA and University of Arizona telescope. The detectors are discrete Si:Bi photoconductors with individual metal oxide semiconductor field effect transistor preamplifiers operating at 4 K. The system uses a liquid helium-cooled slit, order-sorter filter, collimator mirror, grating, and camera mirror arranged in a Czerny-Turner configuration with a cold stop added between the collimator mirror and the grating. The distances between components are chosen so that the collimator mirror images the secondary mirror of the telescope onto the cold stop, thus providing a very effective baffle. Scattered radiation is effectively reduced by using liquid helium-cooled, black baffles to divide the spectrometer into three separate compartments. The system noise-equivalent flux density, when used on the 152 cm telescope from 8 to 13 microns with a resolving power of 50, is 4.4 x 10 to the minus 17th power W/sq cm micron square root of Hz. The main applications are for measuring continuum radiation levels and solid state emission and absorption features in regions of star and planet formation.

Witteborn, F. C.; Bregman, J. D.

1985-01-01

449

[Research on key technologies of all fiber optic Fourier transform spectrometer].  

PubMed

A noval all fiber optic Fourier transform spectrometer based on single mode fiber Mach-Zehnder interferometer is reported. The authors designed a piezoelectric optical phase modulator with two centimeter scan scale, which was used to replace the moving mirror of traditonal Fourier transform spectrometer. The 1 310 nm DFB laser was used as reference light source to make equal interval sampling of test light source's interferogram, and to eliminate errors of nonlinear modulation. Through making the inverse Fourier transform to test light source's interferogram, the authors obtained the spectrum of test source. The spectrum of ASE broadband light source was measured by FFTS system, and the experiment result agrees with that tested by grating spectrometer. Finally, the authors utilized fiber grating as sample to measure the resolution of FFTS system, and the spectral resolution is 0.78 cm(-1). PMID:19798938

Wang, An; Zhu, Ling; Zhang, Long; Liu, Yong; Zhu, Zhen; Li, Zhi-Gang; Wu, Jian-Dong; Fan, Yan-Ping

2009-07-01

450

Instrument design and test results of the new all-reflection spatial heterodyne spectrometer  

NASA Technical Reports Server (NTRS)

An all-reflection spatial heterodyne spectrometer (SHS) has been recently developed. The advantages over conventional high-resolution grating spectrometers are that the SHS requires no mechanical scanning, a self-compensating optical design permits easy alignment, and it is much smaller than other spectrometers of comparable resolution. Since all beam-splits and recombinations occur by reflection off of a diffraction grating, the interferometer is capable of operating well into the extreme ultraviolet (EUV) and possibly into the soft