Optical Characterization of the SPT-3G Camera

NASA Astrophysics Data System (ADS)

Pan, Z.; Ade, P. A. R.; Ahmed, Z.; Anderson, A. J.; Austermann, J. E.; Avva, J. S.; Thakur, R. Basu; Bender, A. N.; Benson, B. A.; Carlstrom, J. E.; Carter, F. W.; Cecil, T.; Chang, C. L.; Cliche, J. F.; Cukierman, A.; Denison, E. V.; de Haan, T.; Ding, J.; Dobbs, M. A.; Dutcher, D.; Everett, W.; Foster, A.; Gannon, R. N.; Gilbert, A.; Groh, J. C.; Halverson, N. W.; Harke-Hosemann, A. H.; Harrington, N. L.; Henning, J. W.; Hilton, G. C.; Holzapfel, W. L.; Huang, N.; Irwin, K. D.; Jeong, O. B.; Jonas, M.; Khaire, T.; Kofman, A. M.; Korman, M.; Kubik, D.; Kuhlmann, S.; Kuo, C. L.; Lee, A. T.; Lowitz, A. E.; Meyer, S. S.; Michalik, D.; Montgomery, J.; Nadolski, A.; Natoli, T.; Nguyen, H.; Noble, G. I.; Novosad, V.; Padin, S.; Pearson, J.; Posada, C. M.; Rahlin, A.; Ruhl, J. E.; Saunders, L. J.; Sayre, J. T.; Shirley, I.; Shirokoff, E.; Smecher, G.; Sobrin, J. A.; Stark, A. A.; Story, K. T.; Suzuki, A.; Tang, Q. Y.; Thompson, K. L.; Tucker, C.; Vale, L. R.; Vanderlinde, K.; Vieira, J. D.; Wang, G.; Whitehorn, N.; Yefremenko, V.; Yoon, K. W.; Young, M. R.

2018-05-01

The third-generation South Pole Telescope camera is designed to measure the cosmic microwave background across three frequency bands (centered at 95, 150 and 220 GHz) with ˜ 16,000 transition-edge sensor (TES) bolometers. Each multichroic array element on a detector wafer has a broadband sinuous antenna that couples power to six TESs, one for each of the three observing bands and both polarizations, via lumped element filters. Ten detector wafers populate the detector array, which is coupled to the sky via a large-aperture optical system. Here we present the frequency band characterization with Fourier transform spectroscopy, measurements of optical time constants, beam properties, and optical and polarization efficiencies of the detector array. The detectors have frequency bands consistent with our simulations and have high average optical efficiency which is 86, 77 and 66% for the 95, 150 and 220 GHz detectors. The time constants of the detectors are mostly between 0.5 and 5 ms. The beam is round with the correct size, and the polarization efficiency is more than 90% for most of the bolometers.

Functional Description of Read-out Electronics for Time-Domain Multiplexed Bolometers for Millimeter and Sub-millimeter Astronomy

NASA Astrophysics Data System (ADS)

Battistelli, E. S.; Amiri, M.; Burger, B.; Halpern, M.; Knotek, S.; Ellis, M.; Gao, X.; Kelly, D.; Macintosh, M.; Irwin, K.; Reintsema, C.

2008-05-01

We have developed multi-channel electronics (MCE) which work in concert with time-domain multiplexors developed at NIST, to control and read signals from large format bolometer arrays of superconducting transition edge sensors (TESs). These electronics were developed as part of the Submillimeter Common-User Bolometer Array-2 (SCUBA2 ) camera, but are now used in several other instruments. The main advantages of these electronics compared to earlier versions is that they are multi-channel, fully programmable, suited for remote operations and provide a clean geometry, with no electrical cabling outside of the Faraday cage formed by the cryostat and the electronics chassis. The MCE is used to determine the optimal operating points for the TES and the superconducting quantum interference device (SQUID) amplifiers autonomously. During observation, the MCE execute a running PID-servo and apply to each first stage SQUID a feedback signal necessary to keep the system in a linear regime at optimal gain. The feedback and error signals from a ˜1000-pixel array can be written to hard drive at up to 2 kHz.

Investigation of the Neutral Gas Pressure Effect on the Metal Resistive Bolometer

NASA Astrophysics Data System (ADS)

Zhang, D.; Giannone, L.; Grulke, O.; Piechotka, M.; Windisch, T.; Stark, A.; Klinger, T.

2008-03-01

The bolometer system planned for W7-X consists mainly of metal (Au) resistive detector arrays. All the detectors are exposed to neutral gas environment. The thin bolometer foil used for detecting the radiated power loss may be sensitive to the neutral gas pressure due to the strain gauge effect. Recently, a prototype of this kind of bolometer camera consisting of 12 channels has been installed on the cylindrical plasma device VINETA in order to investigate the influences of the neutral gas pressure on the bolometer signals. Experiments are carried out for Ar-discharges under different gas pressure conditions. It is found that the pressure effect of the neutral gas can make considerable contributions, thus inducing non-negligible errors of the results in most of the investigated cases. Using the VINETA plasmas (Ar, Te<10 eV, ne<10-19 m-3) as examples, the paper demonstrates and discusses how to minimize the neutral gas effects, especially in the data analysis process. The radiated power and the radiation intensity profile obtained in helicon discharges are presented.

Uncooled Terahertz real-time imaging 2D arrays developed at LETI: present status and perspectives

NASA Astrophysics Data System (ADS)

Simoens, François; Meilhan, Jérôme; Dussopt, Laurent; Nicolas, Jean-Alain; Monnier, Nicolas; Sicard, Gilles; Siligaris, Alexandre; Hiberty, Bruno

2017-05-01

As for other imaging sensor markets, whatever is the technology, the commercial spread of terahertz (THz) cameras has to fulfil simultaneously the criteria of high sensitivity and low cost and SWAP (size, weight and power). Monolithic silicon-based 2D sensors integrated in uncooled THz real-time cameras are good candidates to meet these requirements. Over the past decade, LETI has been studying and developing such arrays with two complimentary technological approaches, i.e. antenna-coupled silicon bolometers and CMOS Field Effect Transistors (FET), both being compatible to standard silicon microelectronics processes. LETI has leveraged its know-how in thermal infrared bolometer sensors in developing a proprietary architecture for THz sensing. High technological maturity has been achieved as illustrated by the demonstration of fast scanning of large field of view and the recent birth of a commercial camera. In the FET-based THz field, recent works have been focused on innovative CMOS read-out-integrated circuit designs. The studied architectures take advantage of the large pixel pitch to enhance the flexibility and the sensitivity: an embedded in-pixel configurable signal processing chain dramatically reduces the noise. Video sequences at 100 frames per second using our 31x31 pixels 2D Focal Plane Arrays (FPA) have been achieved. The authors describe the present status of these developments and perspectives of performance evolutions are discussed. Several experimental imaging tests are also presented in order to illustrate the capabilities of these arrays to address industrial applications such as non-destructive testing (NDT), security or quality control of food.

Infrared-Bolometer Arrays with Reflective Backshorts

NASA Technical Reports Server (NTRS)

Miller, Timothy M.; Abrahams, John; Allen, Christine A.

2011-01-01

Integrated circuits that incorporate square arrays of superconducting-transition- edge bolometers with optically reflective backshorts are being developed for use in image sensors in the spectral range from far infrared to millimeter wavelengths. To maximize the optical efficiency (and, thus, sensitivity) of such a sensor at a specific wavelength, resonant optical structures are created by placing the backshorts at a quarter wavelength behind the bolometer plane. The bolometer and backshort arrays are fabricated separately, then integrated to form a single unit denoted a backshort-under-grid (BUG) bolometer array. In a subsequent fabrication step, the BUG bolometer array is connected, by use of single-sided indium bump bonding, to a readout device that comprises mostly a superconducting quantum interference device (SQUID) multiplexer circuit. The resulting sensor unit comprising the BUG bolometer array and the readout device is operated at a temperature below 1 K. The concept of increasing optical efficiency by use of backshorts at a quarter wavelength behind the bolometers is not new. Instead, the novelty of the present development lies mainly in several features of the design of the BUG bolometer array and the fabrication sequence used to implement the design. Prior to joining with the backshort array, the bolometer array comprises, more specifically, a square grid of free-standing molybdenum/gold superconducting-transition-edge bolometer elements on a 1.4- m-thick top layer of silicon that is part of a silicon support frame made from a silicon-on-insulator wafer. The backshort array is fabricated separately as a frame structure that includes support beams and contains a correspond - ing grid of optically reflective patches on a single-crystal silicon substrate. The process used to fabricate the bolometer array includes standard patterning and etching steps that result in the formation of deep notches in the silicon support frame. These notches are designed to interlock with the support beams on the backshort-array structure to provide structural support and precise relative positioning. The backshort-array structure is inserted in the silicon support frame behind the bolometer array, and the notches in the frame serve to receive the support beams of the backshort-array structure and thus determine the distance between the backshort and bolometer planes. The depth of the notches and, thus, the distance between the backshort and bolometer planes, can be tailored to a value between 25 to 300 m adjusting only a few process steps. The backshort array is designed so as not to interfere with the placement of indium bumps for subsequent indium bump-bonding to the multiplexing readout circuitry

Low-cost far infrared bolometer camera for automotive use

NASA Astrophysics Data System (ADS)

Vieider, Christian; Wissmar, Stanley; Ericsson, Per; Halldin, Urban; Niklaus, Frank; Stemme, Göran; Källhammer, Jan-Erik; Pettersson, Håkan; Eriksson, Dick; Jakobsen, Henrik; Kvisterøy, Terje; Franks, John; VanNylen, Jan; Vercammen, Hans; VanHulsel, Annick

2007-04-01

A new low-cost long-wavelength infrared bolometer camera system is under development. It is designed for use with an automatic vision algorithm system as a sensor to detect vulnerable road users in traffic. Looking 15 m in front of the vehicle it can in case of an unavoidable impact activate a brake assist system or other deployable protection system. To achieve our cost target below €100 for the sensor system we evaluate the required performance and can reduce the sensitivity to 150 mK and pixel resolution to 80 x 30. We address all the main cost drivers as sensor size and production yield along with vacuum packaging, optical components and large volume manufacturing technologies. The detector array is based on a new type of high performance thermistor material. Very thin Si/SiGe single crystal multi-layers are grown epitaxially. Due to the resulting valence barriers a high temperature coefficient of resistance is achieved (3.3%/K). Simultaneously, the high quality crystalline material provides very low 1/f-noise characteristics and uniform material properties. The thermistor material is transferred from the original substrate wafer to the read-out circuit using adhesive wafer bonding and subsequent thinning. Bolometer arrays can then be fabricated using industry standard MEMS process and materials. The inherently good detector performance allows us to reduce the vacuum requirement and we can implement wafer level vacuum packaging technology used in established automotive sensor fabrication. The optical design is reduced to a single lens camera. We develop a low cost molding process using a novel chalcogenide glass (GASIR®3) and integrate anti-reflective and anti-erosion properties using diamond like carbon coating.

Antenna-Coupled Bolometer Arrays for Astrophysics

NASA Astrophysics Data System (ADS)

Bock, James

Bolometers offer the best sensitivity in the far-infrared to millimeter-wave region of the electromagnetic spectrum. We are developing arrays of feedhorn-coupled bolometers for the ESA/NASA Planck Surveyor and Herschel Space Observatory. Advances in the format and sensitivity of bolometric focal plane array enables future astrophysics mission opportunities, such as CMB polarimetry and far-infrared/submillimeter spectral line surveys. Compared to bolometers with extended area radiation absorbers, antenna-coupled bolometers offer active volumes that are orders of magnitude smaller. Coupled to lithographed micro-strip filters and antennas, antenna-coupled bolometer arrays allow flexible focal plane architectures specialized for imaging, polarimetry, and spectroscopy. These architectures greatly reduce the mass of sub-Kelvin bolometer focal planes that drive the design of bolometric instrumentation.

Antenna-coupled TES bolometers used in BICEP2, Keck Array, and SPIDER

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

Ade, P. A. R.; Aikin, R. W.; Amiri, M.

We have developed antenna-coupled transition-edge sensor bolometers for a wide range of cosmic microwave background (CMB) polarimetry experiments, including Bicep2, Keck Array, and the balloon borne Spider. These detectors have reached maturity and this paper reports on their design principles, overall performance, and key challenges associated with design and production. Our detector arrays repeatedly produce spectral bands with 20%–30% bandwidth at 95, 150, or 230 GHz. The integrated antenna arrays synthesize symmetric co-aligned beams with controlled side-lobe levels. Cross-polarized response on boresight is typicallymore » $$\\sim 0.5\\%$$, consistent with cross-talk in our multiplexed readout system. End-to-end optical efficiencies in our cameras are routinely 35% or higher, with per detector sensitivities of NET ~ 300 $$\\mu {{\\rm{K}}}_{\\mathrm{CMB}}\\sqrt{{\\rm{s}}}$$. Thanks to the scalability of this design, we have deployed 2560 detectors as 1280 matched pairs in Keck Array with a combined instantaneous sensitivity of $$\\sim 9\\;\\mu {{\\rm{K}}}_{\\mathrm{CMB}}\\sqrt{{\\rm{s}}}$$, as measured directly from CMB maps in the 2013 season. Furthermore, similar arrays have recently flown in the Spider instrument, and development of this technology is ongoing.« less

Antenna-coupled TES bolometers used in BICEP2, Keck Array, and SPIDER

DOE PAGES

Ade, P. A. R.; Aikin, R. W.; Amiri, M.; ...

2015-10-20

We have developed antenna-coupled transition-edge sensor bolometers for a wide range of cosmic microwave background (CMB) polarimetry experiments, including Bicep2, Keck Array, and the balloon borne Spider. These detectors have reached maturity and this paper reports on their design principles, overall performance, and key challenges associated with design and production. Our detector arrays repeatedly produce spectral bands with 20%–30% bandwidth at 95, 150, or 230 GHz. The integrated antenna arrays synthesize symmetric co-aligned beams with controlled side-lobe levels. Cross-polarized response on boresight is typicallymore » $$\\sim 0.5\\%$$, consistent with cross-talk in our multiplexed readout system. End-to-end optical efficiencies in our cameras are routinely 35% or higher, with per detector sensitivities of NET ~ 300 $$\\mu {{\\rm{K}}}_{\\mathrm{CMB}}\\sqrt{{\\rm{s}}}$$. Thanks to the scalability of this design, we have deployed 2560 detectors as 1280 matched pairs in Keck Array with a combined instantaneous sensitivity of $$\\sim 9\\;\\mu {{\\rm{K}}}_{\\mathrm{CMB}}\\sqrt{{\\rm{s}}}$$, as measured directly from CMB maps in the 2013 season. Furthermore, similar arrays have recently flown in the Spider instrument, and development of this technology is ongoing.« less

Ultralow-Background Large-Format Bolometer Arrays

NASA Technical Reports Server (NTRS)

Benford, Dominic; Chervenak, Jay; Irwin, Kent; Moseley, S. Harvey; Oegerle, William (Technical Monitor)

2002-01-01

In the coming decade, work will commence in earnest on large cryogenic far-infrared telescopes and interferometers. All such observatories - for example, SAFIR, SPIRIT, and SPECS - require large format, two dimensional arrays of close-packed detectors capable of reaching the fundamental limits imposed by the very low photon backgrounds present in deep space. In the near term, bolometer array architectures which permit 1000 pixels - perhaps sufficient for the next generation of space-based instruments - can be arrayed efficiently. Demonstrating the necessary performance, with Noise Equivalent Powers (NEPs) of order 10-20 W/square root of Hz, will be a hurdle in the coming years. Superconducting bolometer arrays are a promising technology for providing both the performance and the array size necessary. We discuss the requirements for future detector arrays in the far-infrared and submillimeter, describe the parameters of superconducting bolometer arrays able to meet these requirements, and detail the present and near future technology of superconducting bolometer arrays. Of particular note is the coming development of large format planar arrays with absorber-coupled and antenna-coupled bolometers.

GISMO, a 2 mm Bolometer Camera Optimized for the Study of High Redshift Galaxies

NASA Technical Reports Server (NTRS)

Staguhn, J.

2007-01-01

The 2mm spectral range provides a unique terrestrial window enabling ground based observations of the earliest active dusty galaxies in the universe and thereby allowing a better constraint on the star formation rate in these objects. We present a progress report for our bolometer camera GISMO (the Goddard-IRAM Superconducting 2-Millimeter Observer), which will obtain large and sensitive sky maps at this wavelength. The instrument will be used at the IRAM 30 m telescope and we expect to install it at the telescope in 2007. The camera uses an 8 x 16 planar array of multiplexed TES bolometers, which incorporates our recently designed Backshort Under Grid (BUG) architecture. GISMO will be very efficient at detecting sources serendipitously in large sky surveys. With the background limited performance of the detectors, the camera provides significantly greater imaging sensitivity and mapping speed at this wavelength than has previously been possible. The major scientific driver for the instrument is to provide the IRAM 30 m telescope with the capability to rapidly observe galactic and extragalactic dust emission, in particular from high-zeta ULI RGs and quasar s, even in the summer season. The instrument will fill in the SEDs of high redshift galaxies at the Rayleigh-Jeans part of the dust emission spectrum, even at the highest redshifts. Our source count models predict that GISMO will serendipitously detect one galaxy every four hours on the blank sky, and that one quarter of these galaxies will be at a redshift of zeta 6.5.

Superconducting Bolometer Array Architectures

NASA Technical Reports Server (NTRS)

Benford, Dominic; Chervenak, Jay; Irwin, Kent; Moseley, S. Harvey; Shafer, Rick; Staguhn, Johannes; Wollack, Ed; Oegerle, William (Technical Monitor)

2002-01-01

The next generation of far-infrared and submillimeter instruments require large arrays of detectors containing thousands of elements. These arrays will necessarily be multiplexed, and superconducting bolometer arrays are the most promising present prospect for these detectors. We discuss our current research into superconducting bolometer array technologies, which has recently resulted in the first multiplexed detections of submillimeter light and the first multiplexed astronomical observations. Prototype arrays containing 512 pixels are in production using the Pop-Up Detector (PUD) architecture, which can be extended easily to 1000 pixel arrays. Planar arrays of close-packed bolometers are being developed for the GBT (Green Bank Telescope) and for future space missions. For certain applications, such as a slewed far-infrared sky survey, feedhorncoupling of a large sparsely-filled array of bolometers is desirable, and is being developed using photolithographic feedhorn arrays. Individual detectors have achieved a Noise Equivalent Power (NEP) of -10(exp 17) W/square root of Hz at 300mK, but several orders of magnitude improvement are required and can be reached with existing technology. The testing of such ultralow-background detectors will prove difficult, as this requires optical loading of below IfW. Antenna-coupled bolometer designs have advantages for large format array designs at low powers due to their mode selectivity.

Wide-field Imaging Survey of Dust Continuum Emissions at lambda = 1.1 mm toward the Chamaeleon and Lupus Regions with AzTEC on ASTE

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

Momose, Munetake; Hiramatsu, Masaaki; Tsukagoshi, Takashi

2009-08-05

We carried out an imaging survey of dust continuum emissions toward the Chamaeleon and Lupus regions. Observations were made with the 144-element bolometer array camera AzTEC mounted on the 10-meter sub-millimeter telescope ASTE during 2007-2008. The preliminary results of disk search and the cloud structure of Lupus III are presented.

The Polarization-Sensitive Bolometers for SPICA and their Potential Use for Ground-Based Application

NASA Astrophysics Data System (ADS)

Reveret, Vincent

2018-01-01

CEA is leading the development of Safari-POL, an imaging-polarimeter aboard the SPICA space observatory (ESA M5). SPICA will be able to reach unprecedented sensitivities thanks to its cooled telescope and its ultra-sensitive detectors. The detector assembly of Safari-POL holds three arrays that are cooled down to 50 mK and correspond to three spectral bands : 100, 200 and 350 microns. The detectors (silicon bolometers), benefit from the Herschel/PACS legacy and are also a big step forward in term of sensitivity (improved by two orders of magnitude compared to PACS bolometers) and for polarimetry capabilities. Indeed, each pixel is intrinsically sensitive to two polarization components (Horizontal and Vertical). We will present the Safari-POL concept, the first results of measurements made on the detectors, and future plans for possible ground-based instruments using this technology. We will also present the example of the ArTéMiS camera, installed at APEX, that was developped as a ground-based conterpart of the PACS photometer.

Two-dimensional array of cold-electron bolometers for high-sensitivity polarization measurements

NASA Astrophysics Data System (ADS)

Kuzmin, L. S.

2012-01-01

A new concept of a two-dimensional array of cold-electron bolometers with distributed dipole antennas in the focal plane for high-sensitivity polarization measurements is proposed. The concept gives a unique combination of high polarization resolution due to a large uniforms array of cold-electron bolometers and optimal matching with junction field effect transistor (JFET) amplifiers because of flexibility in direct-current connections. The noise characteristics are improved due to arriving-signal power distribution among numerous cold-electron bolometers and an increase in their response. This should lead to a significant increase in the sensitivity and dynamic range compared with competing alternative bolometer technologies. The reliability of the twodimensional array significantly increases due to a series-parallel connection of a large number of cold-electron bolometers. High polarization resolution should be ensured due to uniform covering of a substrate by a two-dimensional array over a large area and the absence of the beam compression to small lumped elements. The fundamental sensitivity limit of the cold-electron bolometer array is smaller than photon noise which is considered to be the ultimate level restricted by the background radiation. Estimates of noise of bolometers with the JFET reading system show the possibility of realizing the ultimate sensitivity below the photon-noise level 5 ・10-17 W/Hz1/2 at a frequency of 350 GHz for an optical load with a power of 5 pW. These parameters correspond to the requirements to the receiving system of a BOOMERanG balloon telescope.

A 65 nm CMOS LNA for Bolometer Application

NASA Astrophysics Data System (ADS)

Huang, Tom Nan; Boon, Chirn Chye; Zhu, Forest Xi; Yi, Xiang; He, Xiaofeng; Feng, Guangyin; Lim, Wei Meng; Liu, Bei

2016-04-01

Modern bolometers generally consist of large-scale arrays of detectors. Implemented in conventional technologies, such bolometer arrays suffer from integrability and productivity issues. Recently, the development of CMOS technologies has presented an opportunity for the massive production of high-performance and highly integrated bolometers. This paper presents a 65-nm CMOS LNA designed for a millimeter-wave bolometer's pre-amplification stage. By properly applying some positive feedback, the noise figure of the proposed LNA is minimized at under 6 dB and the bandwidth is extended to 30 GHz.

Frequency multiplexed superconducting quantum interference device readout of large bolometer arrays for cosmic microwave background measurements.

PubMed

Dobbs, M A; Lueker, M; Aird, K A; Bender, A N; Benson, B A; Bleem, L E; Carlstrom, J E; Chang, C L; Cho, H-M; Clarke, J; Crawford, T M; Crites, A T; Flanigan, D I; de Haan, T; George, E M; Halverson, N W; Holzapfel, W L; Hrubes, J D; Johnson, B R; Joseph, J; Keisler, R; Kennedy, J; Kermish, Z; Lanting, T M; Lee, A T; Leitch, E M; Luong-Van, D; McMahon, J J; Mehl, J; Meyer, S S; Montroy, T E; Padin, S; Plagge, T; Pryke, C; Richards, P L; Ruhl, J E; Schaffer, K K; Schwan, D; Shirokoff, E; Spieler, H G; Staniszewski, Z; Stark, A A; Vanderlinde, K; Vieira, J D; Vu, C; Westbrook, B; Williamson, R

2012-07-01

A technological milestone for experiments employing transition edge sensor bolometers operating at sub-Kelvin temperature is the deployment of detector arrays with 100s-1000s of bolometers. One key technology for such arrays is readout multiplexing: the ability to read out many sensors simultaneously on the same set of wires. This paper describes a frequency-domain multiplexed readout system which has been developed for and deployed on the APEX-SZ and South Pole Telescope millimeter wavelength receivers. In this system, the detector array is divided into modules of seven detectors, and each bolometer within the module is biased with a unique ∼MHz sinusoidal carrier such that the individual bolometer signals are well separated in frequency space. The currents from all bolometers in a module are summed together and pre-amplified with superconducting quantum interference devices operating at 4 K. Room temperature electronics demodulate the carriers to recover the bolometer signals, which are digitized separately and stored to disk. This readout system contributes little noise relative to the detectors themselves, is remarkably insensitive to unwanted microphonic excitations, and provides a technology pathway to multiplexing larger numbers of sensors.

Imaging bolometer

DOEpatents

Wurden, G.A.

1999-01-19

Radiation-hard, steady-state imaging bolometer is disclosed. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas. 2 figs.

Imaging bolometer

DOEpatents

Wurden, Glen A.

1999-01-01

Radiation-hard, steady-state imaging bolometer. A bolometer employing infrared (IR) imaging of a segmented-matrix absorber of plasma radiation in a cooled-pinhole camera geometry is described. The bolometer design parameters are determined by modeling the temperature of the foils from which the absorbing matrix is fabricated by using a two-dimensional time-dependent solution of the heat conduction equation. The resulting design will give a steady-state bolometry capability, with approximately 100 Hz time resolution, while simultaneously providing hundreds of channels of spatial information. No wiring harnesses will be required, as the temperature-rise data will be measured via an IR camera. The resulting spatial data may be used to tomographically investigate the profile of plasmas.

Enhancing the spectral response of filled bolometer arrays for submillimeter astronomy.

PubMed

Revéret, Vincent; Rodriguez, Louis; Agnèse, Patrick

2010-12-10

Future missions for astrophysical studies in the submillimeter region will need detectors with very high sensitivity and large fields of view. Bolometer arrays can fulfill these requirements over a very broad band. We describe a technique that enables bolometer arrays that use quarter-wave cavities to have a high spectral response over most of the submillimeter band. This technique is based on the addition on the front of the array of an antireflecting dielectric layer. The optimum parameters (layer thickness and distance to the array) are determined by a 2D analytic code. This general principle is applied to the case of Herschel PACS bolometers (optimized for the 60 to 210 μm band). As an example, we demonstrate experimentally that a PACS array covered by a 138 μm thick silicon layer can improve the spectral response by a factor of 1.7 in the 450 μm band.

Bolometers for millimeter-wave Cosmology

NASA Astrophysics Data System (ADS)

Bock, James J.

2002-05-01

Bolometers offer high sensitivity for observations of the cosmic microwave background, Sunyaev-Zel'Dovich effect in clusters, and far-infrared galaxies. Near background-limited performance may be realized even under the low background conditions available from a space-borne platform. We discuss the achieved performance of silicon nitride micromesh (`spider web') bolometers readout by NTD Ge thermistors. We are developing arrays of such bolometers coupled to single-mode feedhorns. CMB polarization may be studies using a new absorber geometry allowing simultaneous detection of both linear polarizations in a single feedhorn with two individual detectors. Finally we discuss a new bolometer architecture consisting of an array of slot antennae coupled to filters and bolometers via superconducting microstrip. .

Diagnostics for Z-pinch implosion experiments on PTS

NASA Astrophysics Data System (ADS)

Ren, X. D.; Huang, X. B.; Zhou, S. T.; Zhang, S. Q.; Dan, J. K.; Li, J.; Cai, H. C.; Wang, K. L.; Ouyang, K.; Xu, Q.; Duan, S. C.; Chen, G. H.; Wang, M.; Feng, S. P.; Yang, L. B.; Xie, W. P.; Deng, J. J.

2014-12-01

The preliminary experiments of wire array implosion were performed on PTS, a 10 MA z-pinch driver with a 70 ns rise time. A set of diagnostics have been developed and fielded on PTS to study pinch physics and implosion dynamics of wire array. Radiated power measurement for soft x-rays was performed by multichannel filtered x-ray diode array, and flat spectral responses x-ray diode detector. Total x-ray yield was measured by a calibrated, unfiltered nickel bolometer which was also used to obtain pinch power. Multiple time-gated pinhole cameras were used to produce spatial-resolved images of x-ray self-emission from plasmas. Two time-integrated pinhole cameras were used respectively with 20-μm Be filter and with multilayer mirrors to record images produced by >1-keV and 277±5 eV self-emission. An optical streak camera was used to produce radial implosion trajectories, and an x-ray streak camera paired with a horizontal slit was used to record a continuous time-history of emission with one-dimensional spatial resolution. A frequency-doubled Nd:YAG laser (532 nm) was used to produce four frame laser shadowgraph images with 6 ns time interval. We will briefly describe each of these diagnostics and present some typical results from them.

Comparison of the Effects of Magnetic Field on Low Noise MoAu and TiAu TES Bolometers

NASA Astrophysics Data System (ADS)

Hijmering, R. A.; Khosropanah, P.; Ridder, M.; Gao, J. R.; Hoevers, H.; Jackson, B.; Goldie, D.; Withington, S.; Kozorezov, A. G.

2014-08-01

Recently we have reported on the effects of magnetic field on our low noise (NEP = 4 W/Hz) [1] TiAu TES bolometers that are being developed at SRON for the SAFARI FIR Imaging Spectrometer on SPICA telescope that will be operated in three different wavelength bands: S-band for 30-60 , M-band for 60-110 and L-band for 110-210 . The arrays for the S- and M- band will be based on TiAu TES bolometer arrays, developed by SRON. The L-band array will be based on a MoAu TES bolometer developed by University of Cambridge. We have investigated the effect of the magnetic field on the current, responsivity, speed and critical current for both the TiAu and MoAu TES bolometers in our high accuracy magnetic field set-up. A clear difference in weak link behavior is observed between the two types of TES bolometers in both strength of the effect and period of the oscillations.

Arrays of membrane isolated yttrium-barium-copper-oxide kinetic inductance bolometers

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

Lindeman, M. A., E-mail: mark.a.lindeman@jpl.nasa.gov; Bonetti, J. A.; Bumble, B.

We are developing of arrays of membrane isolated resonator-bolometers, each with a kinetic inductance device (KID) to measure the temperature of the membrane. The KIDs are fabricated out of the high temperature superconductor YBCO to allow operation at relatively high temperatures. The bolometers are designed to offer higher sensitivity than sensors operating at 300 K, but they require less expensive and lighter weight cooling than even more sensitive conventional superconducting detectors operating at lower temperatures. The bolometer arrays are applicable as focal planes in infrared imaging spectrometers, such as for planetary science missions or earth observing satellites. We describe the devicesmore » and present measurements of their sensitivity.« less

CCAM: A novel millimeter-wave instrument using a close-packed TES bolometer array

NASA Astrophysics Data System (ADS)

Lau, Judy M.

This thesis describes CCAM, an instrument designed to map the Cosmic Microwave Background (CMB), and also presents some of the initial measurements made with CCAM on the Atacama Cosmology Telescope (ACT). CCAM uses a CCD-like camera of millimeter-wave TES bolometers. It employs new detector technology, read-out electronics, cold re-imaging optics, and cryogenics to obtain high sensitivity CMB anisotropy measurements. The free-standing 8×32 close-packed array of pop- up TES detectors is the first of its kind to observe the sky at 145 GHz. We present the design of the receiver including the antireflection coated silicon lens re-imaging system, construction and optimization of the pulse tube/ sorption refrigerator cryogenic system, as well as the technology developed to integrate eight 1×32 TES columns and accompanying read-out electronics in to an array of 256 millimeter-wave detectors into a focal plane area of 3.5 cm 2. The performance of the detectors and optics prior to deployment at the ACT site in Chile are reported as well as preliminary performance results of the instrument when optically paired with the ACT telescope in the summer of 2007. Here, we also report on the feasibility of the TES detector array to measure polarization when coupled to a rotating birefringent sapphire half wave plate and wire-grid polarizer.

Attempt to the detection of small wildfire by the uncooled micro bolometer camera onboard 50 kg class satellite

NASA Astrophysics Data System (ADS)

Fukuhara, T.; Kouyama, T.; Kato, S.; Nakamura, R.

2016-12-01

University International Formation Mission (UNIFORM) in Japan started in 2011 is an ambitious project that specialized to surveillance of small wildfire to contribute to provide fire information for initial suppression. Final aim of the mission is to construct a constellation with several 50 kg class satellites for frequent and exclusive observation. The uncooled micro-bolometer camera with 640 x 480 pixels based on commercial products has been newly developed for the first satellite. It has been successfully launched on 24 May 2014 and injected to the Sun-Synchronous orbit at local time of 12:00 with altitude of 628 km. The camera has been detected considerable hotspots not only wildfire but also volcanoes. Brightness temperature observed on orbit has been verified and scale of observed wildfire has been roughly presumed; the smallest wildfire ever detected has flame zone less than 2 x 103 m2. It is one tenth of initial requirement estimated in design process; our camera has enough ability to discover small wildfire and to provide beneficial information for fire control with low cost and quick fabrication; it would contribute to practical utility especially in developing nations. A next camera is available for new wildfire mission with satellite constellation; it has already developed for flight. Pixel arrays increasing to 1024 x 768, spatial resolution becomes fine to detect smaller wildfire whereas the swath of image is kept. This camera would be applied to the future planetary mission for Mars and Asteroid explore, too. When it observes planetary surface, thermal inertia can be estimated from continuous observation. When it observes atmosphere, cloud-top altitude can be estimated from horizontal temperature distribution.

Kilopixel Pop-Up Bolometer Arrays for the Atacama Cosmology Telescope

NASA Technical Reports Server (NTRS)

Chervenak, J. A.; Wollack, E.; Henry, R.; Moseley, S. H.; Niemack, M.; Staggs, S.; Page, L.; Doriese, R.; Hilton, G. c.; Irwin, K. D.

2007-01-01

The recently deployed Atacama Cosmology Telescope (ACT) anticipates first light on its kilopixel array of close-packed transition-edge-sensor bolometers in November of 2007. The instrument will represent a full implementation of the next-generation, large format arrays for millimeter wave astronomy that use superconducting electronics and detectors. Achieving the practical construction of such an array is a significant step toward producing advanced detector arrays for future SOFIA instruments. We review the design considerations for the detector array produced for the ACT instrument. The first light imager consists of 32 separately instrumented 32-channel pop-up bolometer arrays (to create a 32x32 filled array of mm-wave sensors). Each array is instrumented with a 32-channel bias resistor array, Nyquist filter array, and time-division SQUID multiplexer. Each component needed to be produced in relatively large quantities with suitable uniformity to meet tolerances for array operation. An optical design was chosen to maximize absorption at the focal plane while mitigating reflections and stray light. The pop-up geometry (previously implemented with semiconducting detectors and readout on the SHARC II and HAWC instruments) enabled straightforward interface of the superconducting bias and readout circuit with the 2D array of superconducting bolometers. The array construction program balanced fabrication challenges with assembly challenges to deliver the instrument in a timely fashion. We present some of the results of the array build and characterization of its performance.

Infrared technology for satellite power conversion. [antenna arrays and bolometers

NASA Technical Reports Server (NTRS)

Campbell, D. P.; Gouker, M. A.; Gallagher, J. J.

1984-01-01

Successful fabrication of bismuth bolometers led to the observation of antenna action rom array elements. Fabrication of the best antennas arrays was made more facile with finding that increased argon flow during the dc sputtering produced more uniform bismuth films and bonding to antennas must be done with the substrate temperaure below 100 C. Higher temperatures damaged the bolometers. During the testing of the antennas, it was found that the use of a quasi-optical system provided a uniform radiation field. Groups of antennas were bonded in series and in parallel with the parallel configuration showing the greater response.

New technologies for the detection of millimeter and submillimeter waves

NASA Technical Reports Server (NTRS)

Richards, P. L.; Clarke, J.; Gildemeister, J. M.; Lanting, T.; Lee, A. T.

2001-01-01

Voltage-biased superconducting bolometers have many operational advantages over conventional bolometer technology including sensitivity, linearity, speed, and immunity from environmental disturbance. A review is given of the Berkeley program for developing this new technology. Developments include fully lithographed individual bolometers in the spiderweb configuration, arrays of 1024 close-packed absorber-coupled bolometers, antenna-coupled bolometers, and a frequency-domain SQUID (superconducting quantum interference device) readout multiplexer.

NIKA2, a dual-band millimetre camera on the IRAM 30 m telescope to map the cold universe

NASA Astrophysics Data System (ADS)

Désert, F.-X.; Adam, R.; Ade, P.; André, P.; Aussel, H.; Beelen, A.; Benoît, A.; Bideaud, A.; Billot, N.; Bourrion, O.; Calvo, M.; Catalano, A.; Coiffard, G.; Comis, B.; Doyle, S.; Goupy, J.; Kramer, C.; Lagache, G.; Leclercq, S.; Lestrade, J.-F.; Macías-Pérez, J. F.; Maury, A.; Mauskopf, P.; Mayet, F.; Monfardini, A.; Pajot, F.; Pascale, E.; Perotto, L.; Pisano, G.; Ponthieu, N.; Revéret, V.; Ritacco, A.; Rodriguez, L.; Romero, C.; Roussel, H.; Ruppin, F.; Soler, J.; Schuster, K.; Sievers, A.; Triqueneaux, S.; Tucker, C.; Zylka, R.

2016-12-01

A consortium led by Institut Néel (Grenoble) has just finished installing a new powerful millimetre camera NIKA2 on the IRAM 30 m telescope. It has an instantaneous field-of-view of 6.5 arcminutes at both 1.2 and 2.0 mm with polarimetric capabilities at 1.2 mm. NIKA2 provides a near diffraction-limited angular resolution (resp. 12 and 18 arcseconds). The 3 detector arrays are made of more than 1000 KIDs each. KIDs are new superconducting devices emerging as an alternative to bolometers. The commissionning is ongoing in 2016 with a likely opening to the IRAM community in early 2017. NIKA2 is a very promising multi-purpose instrument which will enable many scientific discoveries in the coming decade.

Design and Fabrication Highlights Enabling a 2 mm, 128 Element Bolometer Array for GISMO

NASA Technical Reports Server (NTRS)

Allen, Christine; Benford, Dominic; Miller, Timothy; Staguhn, Johannes; Wollack, Edward; Moseley, Harvey

2007-01-01

The Backshort-Under-Grid (BUG) superconducting bolometer array architecture is intended to be highly versatile, operating in a large range of wavelengths and background conditions. We have undertaken a three-year program to develop key technologies and processes required to build kilopixel arrays. To validate the basic array design and to demonstrate its applicability for future kilopixel arrays, we have chosen to demonstrate a 128 element bolometer array optimized for 2 mm wavelength using a newly built Goddard instrument, GISMO (Goddard /RAM Superconducting 2-millimeter Observer). The arrays are fabricated using batch wafer processing developed and optimized for high pixel yield, low noise, and high uniformity. The molybdenum-gold superconducting transition edge sensors are fabricated using batch sputter deposition and are patterned using dry etch techniques developed at Goddard. With a detector pitch of 2 mm 8x16 array for GISMO occupies nearly one half of the processing area of a 100 mm silicon-on-insulator starting wafer. Two such arrays are produced from a single wafer along with witness samples for process characterization. To provide thermal isolation for the detector elements, at the end of the process over 90% of the silicon must be removed using deep reactive ion etching techniques. The electrical connections for each bolometer element are patterned on the top edge of the square grid supporting the array. The design considerations unique to GISMO, key fabrication challenges, and laboratory experimental results will be presented.

Infrared Spectroscopy Data Reduction with ORAC-DR

NASA Astrophysics Data System (ADS)

Economou, F.; Jenness, T.; Cavanagh, B.; Wright, G. S.; Bridger, A. B.; Kerr, T. H.; Hirst, P.; Adamson, A. J.

ORAC-DR is a flexible and extensible data reduction pipeline suitable for both on-line and off-line use. Since its development it has been in use on-line at UKIRT for data from the infrared cameras UFTI and IRCAM and at JCMT for data from the sub-millimetre bolometer array SCUBA. We have now added a suite of on-line reduction recipes that produces publication quality (or nearly so) data from the CGS4 near-infrared spectrometer and the MICHELLE mid-infrared Echelle spectrometer. As an example, this paper briefly describes some pipeline features for one of the more commonly used observing modes.

5,120 Superconducting Bolometers for the PIPER Balloon-Borne CMB Polarization Experiment

NASA Technical Reports Server (NTRS)

Benford, Dominic J.; Chuss, David T.; Hilton, Gene C.; Irwin, Kent D.; Jethava, Nikhil; Jhabvala, Christine A.; Kogut, Alan J.; Miller, Timothy M.; Moseley, S. Harvey; Rostem, Karwan;

Backshort-Under-Grid arrays for infrared astronomy

NASA Astrophysics Data System (ADS)

Allen, C. A.; Benford, D. J.; Chervenak, J. A.; Chuss, D. T.; Miller, T. M.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

2006-04-01

We are developing a kilopixel, filled bolometer array for space infrared astronomy. The array consists of three individual components, to be merged into a single, working unit; (1) a transition edge sensor bolometer array, operating in the milliKelvin regime, (2) a quarter-wave backshort grid, and (3) superconducting quantum interference device multiplexer readout. The detector array is designed as a filled, square grid of suspended, silicon bolometers with superconducting sensors. The backshort arrays are fabricated separately and will be positioned in the cavities created behind each detector during fabrication. The grids have a unique interlocking feature machined into the walls for positioning and mechanical stability. The spacing of the backshort beneath the detector grid can be set from ˜30 300 μm, by independently adjusting two process parameters during fabrication. The ultimate goal is to develop a large-format array architecture with background-limited sensitivity, suitable for a wide range of wavelengths and applications, to be directly bump bonded to a multiplexer circuit. We have produced prototype two-dimensional arrays having 8×8 detector elements. We present detector design, fabrication overview, and assembly technologies.

The Herschel Space Observatory, Opening the Far Infrared

NASA Astrophysics Data System (ADS)

Pearson, John C.

2009-06-01

The Herschel Space Observatory (Herschel) is a multi user observatory operated by the European Space Agency with a significant NASA contribution. Herschel features a passively cooled 3.5 meter telescope expected to operate near 78 Kelvin and three cryogenic instruments covering the 670 to 57 μm spectral region. The mission life time, determined by the consumption of 2500 liters of liquid helium, is expected to be at least 3.5 years with at least 3 years of operational lifetime in an L2 orbit. The three payload instruments are the Spectral and Photometric Imaging Receiver (SPIRE), Photodetector Array Camera and Spectrometer (PACS), and the Heterodyne Instrument for Far Infrared (HIFI). SPIRE covers 200-670 μm and is a three band bolometer based photometer and a two band imaging Martin-Puplett FTS with a spectral resolution of up to 600. PACS covers 57-200 μm and is a three band bolometer based photometer and a grating slit spectrometer illuminating photoconductor arrays in two bands with a resolution of up to 5000. HIFI covers 480-1272 GHz and 1440-1910 GHz and is a series of seven dual polarization heterodyne receivers with a spectral resolution up to 5×10^6. The observatory performance, selected science program and upcoming opportunities will be discussed.

Commissioning of the FTS-2 Data Reduction Pipeline

NASA Astrophysics Data System (ADS)

Sherwood, M.; Naylor, D.; Gom, B.; Bell, G.; Friberg, P.; Bintley, D.

2015-09-01

FTS-2 is the intermediate resolution Fourier Transform Spectrometer coupled to the SCUBA-2 facility bolometer camera at the James Clerk Maxwell Telescope in Hawaii. Although in principle FTS instruments have the advantage of relatively simple optics compared to other spectrometers, they require more sophisticated data processing to compute spectra from the recorded interferogram signal. In the case of FTS-2, the complicated optical design required to interface with the existing telescope optics introduces performance compromises that complicate spectral and spatial calibration, and the response of the SCUBA-2 arrays introduce interferogram distortions that are a challenge for data reduction algorithms. We present an overview of the pipeline and discuss new algorithms that have been written to correct the noise introduced by unexpected behavior of the SCUBA-2 arrays.

The detector calibration system for the CUORE cryogenic bolometer array

DOE PAGES

Cushman, Jeremy S.; Dally, Adam; Davis, Christopher J.; ...

2016-11-14

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of 130Te and other rare events. The CUORE detector consists of 988 TeO 2 bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires themore » placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. In conclusion, this paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.« less

Far infrared through millimeter backshort-under-grid arrays

NASA Astrophysics Data System (ADS)

Allen, Christine A.; Abrahams, John; Benford, Dominic J.; Chervenak, James A.; Chuss, David T.; Staguhn, Johannes G.; Miller, Timothy M.; Moseley, S. Harvey; Wollack, Edward J.

2006-06-01

We are developing a large-format, versatile, bolometer array for a wide range of infrared through millimeter astronomical applications. The array design consists of three key components - superconducting transition edge sensor bolometer arrays, quarter-wave reflective backshort grids, and Superconducting Quantum Interference Device (SQUID) multiplexer readouts. The detector array is a filled, square grid of bolometers with superconducting sensors. The backshort arrays are fabricated separately and are positioned in the etch cavities behind the detector grid. The grids have unique three-dimensional interlocking features micromachined into the walls for positioning and mechanical stability. The ultimate goal of the program is to produce large-format arrays with background-limited sensitivity, suitable for a wide range of wavelengths and applications. Large-format (kilopixel) arrays will be directly indium bump bonded to a SQUID multiplexer circuit. We have produced and tested 8×8 arrays of 1 mm detectors to demonstrate proof of concept. 8×16 arrays of 2 mm detectors are being produced for a new Goddard Space Flight Center instrument. We have also produced models of a kilopixel detector grid and dummy multiplexer chip for bump bonding development. We present detector design overview, several unique fabrication highlights, and assembly technologies.

Feedhorn-Coupled Transition-Edge Superconducting Bolometer Arrays for Cosmic Microwave Background Polarimetry

NASA Technical Reports Server (NTRS)

Hubmayr, J.; Austermann, J.; Beall, J.; Becker, D.; Cho, H.-M.; Datta, R.; Duff, S. M.; Grace, E.; Halverson, N.; Henderson, S. W.;

Fabricating interlocking support walls, with an adjustable backshort, in a TES bolometer array for far-infrared astronomy

NASA Astrophysics Data System (ADS)

Miller, Timothy M.; Abrahams, John H.; Allen, Christine A.

2006-04-01

We report a fabrication process for deep etching silicon to different depths with a single masking layer, using standard masking and exposure techniques. Using this technique, we have incorporated a deep notch in the support walls of a transition-edge-sensor (TES) bolometer array during the detector back-etch, while simultaneously creating a cavity behind the detector. The notches serve to receive the support beams of a separate component, the Backshort-Under-Grid (BUG), an array of adjustable height quarter-wave backshorts that fill the cavities behind each pixel in the detector array. The backshort spacing, set prior to securing to the detector array, can be controlled from 25 to 300 μm by adjusting only a few process steps. In addition to backshort spacing, the interlocking beams and notches provide positioning and structural support for the ˜1 mm pitch, 8×8 array. This process is being incorporated into developing a TES bolometer array with an adjustable backshort for use in far-infrared astronomy. The masking technique and machining process used to fabricate the interlocking walls will be discussed.

Improved signal to noise ratio and sensitivity of an infrared imaging video bolometer on large helical device by using an infrared periscope

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

Pandya, Shwetang N., E-mail: pandya.shwetang@LHD.nifs.ac.jp; Sano, Ryuichi; Peterson, Byron J.

An Infrared imaging Video Bolometer (IRVB) diagnostic is currently being used in the Large Helical Device (LHD) for studying the localization of radiation structures near the magnetic island and helical divertor X-points during plasma detachment and for 3D tomography. This research demands high signal to noise ratio (SNR) and sensitivity to improve the temporal resolution for studying the evolution of radiation structures during plasma detachment and a wide IRVB field of view (FoV) for tomography. Introduction of an infrared periscope allows achievement of a higher SNR and higher sensitivity, which in turn, permits a twofold improvement in the temporal resolutionmore » of the diagnostic. Higher SNR along with wide FoV is achieved simultaneously by reducing the separation of the IRVB detector (metal foil) from the bolometer's aperture and the LHD plasma. Altering the distances to meet the aforesaid requirements results in an increased separation between the foil and the IR camera. This leads to a degradation of the diagnostic performance in terms of its sensitivity by 1.5-fold. Using an infrared periscope to image the IRVB foil results in a 7.5-fold increase in the number of IR camera pixels imaging the foil. This improves the IRVB sensitivity which depends on the square root of the number of IR camera pixels being averaged per bolometer channel. Despite the slower f-number (f/# = 1.35) and reduced transmission (τ{sub 0} = 89%, due to an increased number of lens elements) for the periscope, the diagnostic with an infrared periscope operational on LHD has improved in terms of sensitivity and SNR by a factor of 1.4 and 4.5, respectively, as compared to the original diagnostic without a periscope (i.e., IRVB foil being directly imaged by the IR camera through conventional optics). The bolometer's field of view has also increased by two times. The paper discusses these improvements in apt details.« less

A superconducting bolometer camera for APEX

NASA Astrophysics Data System (ADS)

Jethava, N.; Kreysa, E.; Siringo, G.; Esch, W.; Gemünd, H.-P.; May, T.; Anders, S.; Fritzsch, L.; Boucher, R.; Zakosarenko, V.; Meyer, H.-G.

2006-06-01

We present the experimental results of voltage-biased superconducting bolometers (VSB) on silicon nitride (Si 3N 4) membranes with niobium wiring developed in collaboration between the Institut fur Physikalische Hochtechnologie (IPHT), Jena, Germany and the Max-Planck-Institut fur Radioastronomie (MPIfR), Bonn, Germany. The bolometer current is measured with the superconducting quantum interference device (SQUID), and as expected, the current responsivity is proportional to the inverse of the bias voltage. The experiments were performed with bilayer gold-palladium molybdenum thermistor at 300 mK 3He cooled cryostat and the desired transition temperature of T c = 450 mK is achieved. The strong negative electro-thermal feedback of the VSB maintains the constant bolometer temperature and reduces the response time from 4 ms to 100 μs. We have tested thermistors of various size and shape on a continuous membrane and achieved a noise equivalent power (NEP) of 3.5 × 10 -16 W/√Hz. The measured NEP is relatively high due to the comparatively high background and high thermal conductance of the unstructured silicon nitride (Si 3N 4) membrane. We have fabricated 8-leg spider structured membranes in three different geometries and the relation between the geometry and the thermal conductance (G) is studied. Using the COSMOS finite element analysis tool, we have modeled the TES bolometers to determine the thermal conductance for different geometries and calculated the various parameters. Due to the demands of large number pixel bolometer camera we plan to implement multiplex readout with integrated SQUIDs in our design.

Indium Hybridization of Large Format TES Bolometer Arrays to Readout Multiplexers for Far-Infrared Astronomy

NASA Technical Reports Server (NTRS)

Miller, Timothy M.; Costen, Nick; Allen, Christine

2007-01-01

This conference poster reviews the Indium hybridization of the large format TES bolometer arrays. We are developing a key technology to enable the next generation of detectors. That is the Hybridization of Large Format Arrays using Indium bonded detector arrays containing 32x40 elements which conforms to the NIST multiplexer readout architecture of 1135 micron pitch. We have fabricated and hybridized mechanical models with the detector chips bonded after being fully back-etched. The mechanical support consists of 30 micron walls between elements Demonstrated electrical continuity for each element. The goal is to hybridize fully functional array of TES detectors to NIST readout.

A report on the laboratory performance of the spectroscopic detector arrays for SPIRE/HSO

NASA Astrophysics Data System (ADS)

Nguyen, Hien T.; Bock, James J.; Ringold, Peter; Battle, John; Elliott, Steven C.; Turner, Anthony D.; Weilert, Mark; Hristov, Viktor V.; Schulz, Bernhard; Ganga, Ken; Zhang, L.; Beeman, Jeffrey W.; Ade, Peter A. R.; Hargrave, Peter C.

2004-10-01

We report the performance of the flight bolometer arrays for the Spectral and Photometric Imaging REceiver (SPIRE) instrument to be on board of the Herschel Space Observatory (HSO). We describe the test setup for the flight Bolometric Detector Assembly (BDA) that allows the characterization of its performance, both dark and optical, in one instrument's cool down. We summarize the laboratory procedure to measure the basic bolometer parameters, optical response time, optical efficiency of bolometer and feedhorn, dark and optical noise, and the overall thermal conductance of the BDA unit. Finally, we present the test results obtained from the two flight units, Spectroscopic Long Wavelength (SLW) and Spectroscopic Short Wavelength (SSW).

Very large scale heterogeneous integration (VLSHI) and wafer-level vacuum packaging for infrared bolometer focal plane arrays

NASA Astrophysics Data System (ADS)

Forsberg, Fredrik; Roxhed, Niclas; Fischer, Andreas C.; Samel, Björn; Ericsson, Per; Hoivik, Nils; Lapadatu, Adriana; Bring, Martin; Kittilsland, Gjermund; Stemme, Göran; Niklaus, Frank

2013-09-01

Imaging in the long wavelength infrared (LWIR) range from 8 to 14 μm is an extremely useful tool for non-contact measurement and imaging of temperature in many industrial, automotive and security applications. However, the cost of the infrared (IR) imaging components has to be significantly reduced to make IR imaging a viable technology for many cost-sensitive applications. This paper demonstrates new and improved fabrication and packaging technologies for next-generation IR imaging detectors based on uncooled IR bolometer focal plane arrays. The proposed technologies include very large scale heterogeneous integration for combining high-performance, SiGe quantum-well bolometers with electronic integrated read-out circuits and CMOS compatible wafer-level vacuum packing. The fabrication and characterization of bolometers with a pitch of 25 μm × 25 μm that are arranged on read-out-wafers in arrays with 320 × 240 pixels are presented. The bolometers contain a multi-layer quantum well SiGe thermistor with a temperature coefficient of resistance of -3.0%/K. The proposed CMOS compatible wafer-level vacuum packaging technology uses Cu-Sn solid-liquid interdiffusion (SLID) bonding. The presented technologies are suitable for implementation in cost-efficient fabless business models with the potential to bring about the cost reduction needed to enable low-cost IR imaging products for industrial, security and automotive applications.

ORAC-DR: One Pipeline for Multiple Telescopes

NASA Astrophysics Data System (ADS)

Cavanagh, B.; Hirst, P.; Jenness, T.; Economou, F.; Currie, M. J.; Todd, S.; Ryder, S. D.

ORAC-DR, a flexible and extensible data reduction pipeline, has been successfully used for real-time data reduction from UFTI and IRCAM (infrared cameras), CGS4 (near-infrared spectrometer), Michelle (mid-infrared imager and echelle spectrometer), at UKIRT; and SCUBA (sub-millimeter bolometer array) at JCMT. We have now added the infrared imaging spectrometers IRIS2 at the Anglo-Australian Telescope and UIST at UKIRT to the list of officially supported instruments. We also present initial integral field unit support for UIST, along with unofficial support for the imager and multi-object spectrograph GMOS at Gemini. This paper briefly describes features of the pipeline along with details of adopting ORAC-DR for other instruments on telescopes around the world.

Integrated Electron-tunneling Refrigerator and TES Bolometer for Millimeter Wave Astronomy

NASA Technical Reports Server (NTRS)

Silverberg, R. F.; Benford, D. J.; Chen, T. C.; Chervenak, J.; Finkbeiner, F.; Moseley, S. H.; Duncan, W.; Miller, N.; Schmidt, D.; Ullom, J.

2005-01-01

We describe progress in the development of a close-packed array of bolometers intended for use in photometric applications at millimeter wavelengths from ground- based telescopes. Each bolometer in the may uses a proximity-effect Transition Edge Sensor (TES) sensing element and each will have integrated Normal-Insulator-Superconductor (NIS) refrigerators to cool the bolometer below the ambient bath temperature. The NIS refrigerators and acoustic-phonon-mode-isolated bolometers are fabricated on silicon. The radiation-absorbing element is mechanically suspended by four legs, whose dimensions are used to control and optimize the thermal conductance of the bolometer. Using the technology developed at NIST, we fabricate NIS refrigerators at the base of each of the suspension legs. The NIS refrigerators remove hot electrons by quantum-mechanical tunneling and are expected to cool the biased (approx.10 pW) bolometers to <170 mK while the bolometers are inside a pumped 3He-cooled cryostat operating at approx.280 mK. This significantly lower temperature at the bolometer allows the detectors to approach background-limited performance despite the simple cryogenic system.

Passive stand-off terahertz imaging with 1 hertz frame rate

NASA Astrophysics Data System (ADS)

May, T.; Zieger, G.; Anders, S.; Zakosarenko, V.; Starkloff, M.; Meyer, H.-G.; Thorwirth, G.; Kreysa, E.

2008-04-01

Terahertz (THz) cameras are expected to be a powerful tool for future security applications. If such a technology shall be useful for typical security scenarios (e.g. airport check-in) it has to meet some minimum standards. A THz camera should record images with video rate from a safe distance (stand-off). Although active cameras are conceivable, a passive system has the benefit of concealed operation. Additionally, from an ethic perspective, the lack of exposure to a radiation source is a considerable advantage in public acceptance. Taking all these requirements into account, only cooled detectors are able to achieve the needed sensitivity. A big leap forward in the detector performance and scalability was driven by the astrophysics community. Superconducting bolometers and midsized arrays of them have been developed and are in routine use. Although devices with many pixels are foreseeable nowadays a device with an additional scanning optic is the straightest way to an imaging system with a useful resolution. We demonstrate the capabilities of a concept for a passive Terahertz video camera based on superconducting technology. The actual prototype utilizes a small Cassegrain telescope with a gyrating secondary mirror to record 2 kilopixel THz images with 1 second frame rate.

Integrated focal plane arrays for millimeter-wave astronomy

NASA Astrophysics Data System (ADS)

Bock, James J.; Goldin, Alexey; Hunt, Cynthia; Lange, Andrew E.; Leduc, Henry G.; Day, Peter K.; Vayonakis, Anastasios; Zmuidzinas, Jonas

2002-02-01

We are developing focal plane arrays of bolometric detectors for sub-millimeter and millimeter-wave astrophysics. We propose a flexible array architecture using arrays of slot antennae coupled via low-loss superconducting Nb transmission line to microstrip filters and antenna-coupled bolometers. By combining imaging and filtering functions with transmission line, we are able to realize unique structures such as a multi-band polarimeter and a planar, dispersive spectrometer. Micro-strip bolometers have significantly smaller active volume than standard detectors with extended absorbers, and can realize higher sensitivity and speed of response. The integrated array has natural immunity to stray radiation or spectral leaks, and minimizes the suspended mass operating at 0.1-0.3 K. We also discuss future space-borne spectroscopy and polarimetry applications. .

Multicolor Detectors for Ultrasensitive Long-Wave Imaging Cameras

NASA Technical Reports Server (NTRS)

Brown, Ari; Benford, Dominic; Chervenak, James; Wollack, Edward

2012-01-01

A document describes a zeptobolometer for ultrasensitive, long-wavelength sensors. GSFC is developing pixels based on the zeptobolometer design that sense three THz wavelengths simultaneously. Two innovations are described in the document: (1) a quasiparticle (QO) filter arrangement that enables a compact multicolor spectrum at the focal plane, and (2) a THz antenna readout by up to three bolometers. The innovations enable high efficiency by greatly reducing high, frequency-dependent microstrip losses, and pixel compactness by eliminating the need for bulky filters in the focal plane. The zeptobolometer is a small TES bolometer, on the scale of a few microns, which can be readily coupled through an impedance-matching resistor to a metal or dielectric antenna. The bolometer is voltage-biased in its superconducting transition, allowing the use of superconducting RF multiplexers to read out large arrays. The antenna is geometrically tapped at three locations so as to efficiently couple radiation of three distinct wavelengths to the individual TESs. The transition edge hot electrons in metals offer a simple, compact arrangement for antenna readout, which can be crucial in the THz where line losses at high frequencies can be substantial. A metallic grill filter acts as a high-pass filter and directs the low-frequency components to a location where they will be absorbed. The absorption spectrum shows that three well-separated THz bands are feasible. The filters can be made from high-purity dielectrics such as float zone silicon or sapphire.

Antenna-coupled Superconducting Bolometers for Observations of the Cosmic Microwave Background Polarization

NASA Astrophysics Data System (ADS)

Myers, Michael James

We describe the development of a novel millimeter-wave cryogenic detector. The device integrates a planar antenna, superconducting transmission line, bandpass filter, and bolometer onto a single silicon wafer. The bolometer uses a superconducting Transition-Edge Sensor (TES) thermistor, which provides substantial advantages over conventional semiconductor bolometers. The detector chip is fabricated using standard micro-fabrication techniques. This highly-integrated detector architecture is particularly well-suited for use in the de- velopment of polarization-sensitive cryogenic receivers with thousands of pixels. Such receivers are needed to meet the sensitivity requirements of next-generation cosmic microwave background polarization experiments. The design, fabrication, and testing of prototype array pixels are described. Preliminary considerations for a full array design are also discussed. A set of on-chip millimeter-wave test structures were developed to help understand the performance of our millimeter-wave microstrip circuits. These test structures produce a calibrated transmission measurement for an arbitrary two-port circuit using optical techniques, rather than a network analyzer. Some results of fabricated test structures are presented.

5,120 Superconducting Bolometers for the PIPER Balloon-Borne CMB Polarization Experiment

NASA Technical Reports Server (NTRS)

Benford, Dominic J.; Chuss, David T.; Hilton, Gene C.; Irwin, Kent D.; Jethava, Nikhil S.; Jhabvala, Christine A.; Kogut, Alan J.; Miller, Timothy M.; Mirel, Paul; Moseley, S. Harvey;

High-performance ferroelectric and magnetoresistive materials for next-generation thermal detector arrays

NASA Astrophysics Data System (ADS)

Todd, Michael A.; Donohue, Paul P.; Watton, Rex; Williams, Dennis J.; Anthony, Carl J.; Blamire, Mark G.

2002-12-01

This paper discusses the potential thermal imaging performance achievable from thermal detector arrays and concludes that the current generation of thin-film ferroelectric and resistance bolometer based detector arrays are limited by the detector materials used. It is proposed that the next generation of large uncooled focal plane arrays will need to look towards higher performance detector materials - particularly if they aim to approach the fundamental performance limits and compete with cooled photon detector arrays. Two examples of bolometer thin-film materials are described that achieve high performance from operating around phase transitions. The material Lead Scandium Tantalate (PST) has a paraelectric-to-ferroelectric phase transition around room temperature and is used with an applied field in the dielectric bolometer mode for thermal imaging. PST films grown by sputtering and liquid-source CVD have shown merit figures for thermal imaging a factor of 2 to 3 times higher than PZT-based pyroelectric thin films. The material Lanthanum Calcium Manganite (LCMO) has a paramagnetic to ferromagnetic phase transition around -20oC. This paper describes recent measurements of TCR and 1/f noise in pulsed laser-deposited LCMO films on Neodymium Gallate substrates. These results show that LCMO not only has high TCR's - up to 30%/K - but also low 1/f excess noise, with bolometer merit figures at least an order of magnitude higher than Vanadium Oxide, making it ideal for the next generation of microbolometer arrays. These high performance properties come at the expense of processing complexities and novel device designs will need to be introduced to realize the potential of these materials in the next generation of thermal detectors.

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

Hattori, K.; Akiba, Y.; Arnold, K.

The readout of transition-edge sensor (TES) bolometers with a large multiplexing factor is key for the next generation cosmic microwave background (CMB) experiment, Polarbear-2, having 7588 TES bolometers. To enable the large arrays, we have been developing a readout system with a multiplexing factor of 40 in the frequency domain. Extending that architecture to 40 bolometers requires an increase in the bandwidth of the SQUID electronics, above 4 MHz. This paper focuses on cryogenic readout and shows how it affects cross talk and the responsivity of the TES bolometers. A series resistance, such as equivalent series resistance of capacitors formore » LC filters, leads to non-linear response of the bolometers. A wiring inductance modulates a voltage across the bolometers and causes cross talk. They should be controlled well to reduce systematic errors in CMB observations. As a result, we have been developing a cryogenic readout with a low series impedance and have tuned bolometers in the middle of their transition at a high frequency (>3 MHz).« less

Development of a prototype infrared imaging bolometer for NSTX-U

NASA Astrophysics Data System (ADS)

van Eden, G. G.; Delgado-Aparicio, L. F.; Gray, T. K.; Jaworski, M. A.; Morgan, T. W.; Peterson, B. J.; Reinke, M. L.; Sano, R.; Mukai, K.; Differ/Pppl Collaboration; Nifs/Pppl Collaboration

2015-11-01

Measurements of the radiated power in fusion reactors are of high importance for studying detachment and the overall power balance. A prototype Infrared Video Bolometer (IRVB) is being developed for NSTX-U complementing resistive bolometer and AXUV diode diagnostics. The IRVB has proven to be a powerful tool on LHD and JT-60U for its 2D imaging quality and reactor environment compatibility. For NSTX-U, a poloidal view of the lower center stack and lower divertor are envisaged for the 2016 run campaign. The IRVB concept images radiation from the plasma onto a 2.5 μm thick 9 x 7 cm2 calibrated Pt foil and monitors its temperature evolution using an IR camera (SB focal plane, 2-12 μm, 128x128 pixels, 1.6 kHz). The power incident on the foil is calculated by solving the 2D +time heat diffusion equation. Benchtop characterization is presented, demonstrating a sensitivity of approximately 20 mK and a noise equivalent power density of 71.5 μW cm-2 for 4x20 bolometer super-pixels and a 50 Hz time response. The hardware design, optimization of camera and detector settings as well as first results of both synthetic and experimental origin are discussed.

Neutron transmutation doped Ge bolometers

NASA Technical Reports Server (NTRS)

Haller, E. E.; Kreysa, E.; Palaio, N. P.; Richards, P. L.; Rodder, M.

1983-01-01

Some conclusions reached are as follow. Neutron Transmutation Doping (NTD) of high quality Ge single crystals provides perfect control of doping concentration and uniformity. The resistivity can be tailored to any given bolometer operating temperature down to 0.1 K and probably lower. The excellent uniformity is advantaged for detector array development.

The 160 TES bolometer read-out using FDM for SAFARI

NASA Astrophysics Data System (ADS)

Hijmering, R. A.; den Hartog, R. H.; van der Linden, A. J.; Ridder, M.; Bruijn, M. P.; van der Kuur, J.; van Leeuwen, B. J.; van Winden, P.; Jackson, B.

2014-07-01

For the read out of the Transition Edge Sensors (TES) bolometer arrays of the SAFARI instrument on the Japanese background-limited far-IR SPICA mission SRON is developing a Frequency Domain Multiplexing (FDM) read-out system. The next step after the successful demonstration of the read out of 38 TES bolometers using FDM was to demonstrate the FDM readout of the required 160 TES bolometers. Of the 160 LC filter and TES bolometer chains 151 have been connected and after cooldown 148 of the resonances could be identified. Although initial operation and locking of the pixels went smoothly the experiment revealed several complications. In this paper we describe the 160 pixel FDM set-up, show the results and discuss the issues faced during operation of the 160 pixel FDM experiment.

[Contrast of Z-Pinch X-Ray Yield Measure Technique].

PubMed

Li, Mo; Wang, Liang-ping; Sheng, Liang; Lu, Yi

2015-03-01

Resistive bolometer and scintillant detection system are two mainly Z-pinch X-ray yield measure techniques which are based on different diagnostic principles. Contrasting the results from two methods can help with increasing precision of X-ray yield measurement. Experiments with different load material and shape were carried out on the "QiangGuang-I" facility. For Al wire arrays, X-ray yields measured by the two techniques were largely consistent. However, for insulating coating W wire arrays, X-ray yields taken from bolometer changed with load parameters while data from scintillant detection system hardly changed. Simulation and analysis draw conclusions as follows: (1) Scintillant detection system is much more sensitive to X-ray photons with low energy and its spectral response is wider than the resistive bolometer. Thus, results from the former method are always larger than the latter. (2) The responses of the two systems are both flat to Al plasma radiation. Thus, their results are consistent for Al wire array loads. (3) Radiation form planar W wire arrays is mainly composed of sub-keV soft X-ray. X-ray yields measured by the bolometer is supposed to be accurate because of the nickel foil can absorb almost all the soft X-ray. (4) By contrast, using planar W wire arrays, data from scintillant detection system hardly change with load parameters. A possible explanation is that while the distance between wires increases, plasma temperature at stagnation reduces and spectra moves toward the soft X-ray region. Scintillator is much more sensitive to the soft X-ray below 200 eV. Thus, although the total X-ray yield reduces with large diameter load, signal from the scintillant detection system is almost the same. (5) Both Techniques affected by electron beams produced by the loads.

Submillimeter video imaging with a superconducting bolometer array

NASA Astrophysics Data System (ADS)

Becker, Daniel Thomas

Millimeter wavelength radiation holds promise for detection of security threats at a distance, including suicide bombers and maritime threats in poor weather. The high sensitivity of superconducting Transition Edge Sensor (TES) bolometers makes them ideal for passive imaging of thermal signals at millimeter and submillimeter wavelengths. I have built a 350 GHz video-rate imaging system using an array of feedhorn-coupled TES bolometers. The system operates at standoff distances of 16 m to 28 m with a measured spatial resolution of 1.4 cm (at 17 m). It currently contains one 251-detector sub-array, and can be expanded to contain four sub-arrays for a total of 1004 detectors. The system has been used to take video images that reveal the presence of weapons concealed beneath a shirt in an indoor setting. This dissertation describes the design, implementation and characterization of this system. It presents an overview of the challenges associated with standoff passive imaging and how these problems can be overcome through the use of large-format TES bolometer arrays. I describe the design of the system and cover the results of detector and optical characterization. I explain the procedure used to generate video images using the system, and present a noise analysis of those images. This analysis indicates that the Noise Equivalent Temperature Difference (NETD) of the video images is currently limited by artifacts of the scanning process. More sophisticated image processing algorithms can eliminate these artifacts and reduce the NETD to 100 mK, which is the target value for the most demanding passive imaging scenarios. I finish with an overview of future directions for this system.

Design of 280 GHz feedhorn-coupled TES arrays for the balloon-borne polarimeter SPIDER

NASA Astrophysics Data System (ADS)

Hubmayr, Johannes; Austermann, Jason E.; Beall, James A.; Becker, Daniel T.; Benton, Steven J.; Bergman, A. Stevie; Bond, J. Richard; Bryan, Sean; Duff, Shannon M.; Duivenvoorden, Adri J.; Eriksen, H. K.; Filippini, Jeffrey P.; Fraisse, A.; Galloway, Mathew; Gambrel, Anne E.; Ganga, K.; Grigorian, Arpi L.; Gualtieri, Riccardo; Gudmundsson, Jon E.; Hartley, John W.; Halpern, M.; Hilton, Gene C.; Jones, William C.; McMahon, Jeffrey J.; Moncelsi, Lorenzo; Nagy, Johanna M.; Netterfield, C. B.; Osherson, Benjamin; Padilla, Ivan; Rahlin, Alexandra S.; Racine, B.; Ruhl, John; Rudd, T. M.; Shariff, J. A.; Soler, J. D.; Song, Xue; Ullom, Joel N.; Van Lanen, Jeff; Vissers, Michael R.; Wehus, I. K.; Wen, Shyang; Wiebe, D. V.; Young, Edward

2016-07-01

We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure the large-scale B-mode polarization of the cosmic microwave background (cmb) in search of the cosmic-inflation, gravitational-wave signature. 280 GHz channels aid this science goal by constraining the level of B-mode contamination from galactic dust emission. We present the focal plane unit design, which consists of a 16x16 array of conical, corrugated feedhorns coupled to a monolithic detector array fabricated on a 150 mm diameter silicon wafer. Detector arrays are capable of polarimetric sensing via waveguide probe-coupling to a multiplexed array of transition-edge-sensor (TES) bolometers. The spider receiver has three focal plane units at 280 GHz, which in total contains 765 spatial pixels and 1,530 polarization sensitive bolometers. By fabrication and measurement of single feedhorns, we demonstrate 14.7° FHWM Gaussian-shaped beams with <1% ellipticity in a 30% fractional bandwidth centered at 280 GHz. We present electromagnetic simulations of the detection circuit, which show 94% band-averaged, single-polarization coupling efficiency, 3% reflection and 3% radiative loss. Lastly, we demonstrate a low thermal conductance bolometer, which is well-described by a simple TES model and exhibits an electrical noise equivalent power (NEP) = 2.6 x 10-17 W/√Hz, consistent with the phonon noise prediction.

Development of readout electronics for POLARBEAR-2 cosmic microwave background experiment

DOE PAGES

Hattori, K.; Akiba, Y.; Arnold, K.; ...

2016-01-06

The readout of transition-edge sensor (TES) bolometers with a large multiplexing factor is key for the next generation cosmic microwave background (CMB) experiment, Polarbear-2, having 7588 TES bolometers. To enable the large arrays, we have been developing a readout system with a multiplexing factor of 40 in the frequency domain. Extending that architecture to 40 bolometers requires an increase in the bandwidth of the SQUID electronics, above 4 MHz. This paper focuses on cryogenic readout and shows how it affects cross talk and the responsivity of the TES bolometers. A series resistance, such as equivalent series resistance of capacitors formore » LC filters, leads to non-linear response of the bolometers. A wiring inductance modulates a voltage across the bolometers and causes cross talk. They should be controlled well to reduce systematic errors in CMB observations. As a result, we have been developing a cryogenic readout with a low series impedance and have tuned bolometers in the middle of their transition at a high frequency (>3 MHz).« less

Advanced ACTPol Low-Frequency Array: Readout and Characterization of Prototype 27 and 39 GHz Transition Edge Sensors

NASA Astrophysics Data System (ADS)

Koopman, B. J.; Cothard, N. F.; Choi, S. K.; Crowley, K. T.; Duff, S. M.; Henderson, S. W.; Ho, S. P.; Hubmayr, J.; Gallardo, P. A.; Nati, F.; Niemack, M. D.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Vavagiakis, E. M.; Wollack, E. J.

2018-05-01

Advanced ACTPol (AdvACT) is a third-generation polarization upgrade to the Atacama Cosmology Telescope, designed to observe the cosmic microwave background (CMB). AdvACT expands on the 90 and 150 GHz transition edge sensor (TES) bolometer arrays of the ACT Polarimeter (ACTPol), adding both high-frequency (HF, 150/230 GHz) and low-frequency (LF, 27/39 GHz) multichroic arrays. The addition of the high- and low-frequency detectors allows for the characterization of synchrotron and spinning dust emission at the low frequencies and foreground emission from galactic dust and dusty star-forming galaxies at the high frequencies. The increased spectral coverage of AdvACT will enable a wide range of CMB science, such as improving constraints on dark energy, the sum of the neutrino masses, and the existence of primordial gravitational waves. The LF array will be the final AdvACT array, replacing one of the MF arrays for a single season. Prior to the fabrication of the final LF detector array, we designed and characterized prototype TES bolometers. Detector geometries in these prototypes are varied in order to inform and optimize the bolometer designs for the LF array, which requires significantly lower noise levels and saturation powers (as low as {˜ } 1 pW) than the higher-frequency detectors. Here we present results from tests of the first LF prototype TES detectors for AdvACT, including measurements of the saturation power, critical temperature, thermal conductance, and time constants. We also describe the modifications to the time-division SQUID readout architecture compared to the MF and HF arrays.

Micromachined poly-SiGe bolometer arrays for infrared imaging and spectroscopy

NASA Astrophysics Data System (ADS)

Leonov, Vladimir N.; Perova, Natalia A.; De Moor, Piet; Du Bois, Bert; Goessens, Claus; Grietens, Bob; Verbist, Agnes; Van Hoof, Chris A.; Vermeiren, Jan P.

2003-03-01

The state-of-the-art characteristics of micromachined polycrystalline SiGe microbolometer arrays are reported. An average NETD of 85 mK at a time constant of 14 ms is already achievable on typical self-supported 50 μm pixels in a linear 64-element array. In order to reach these values, the design optimization was performed based on the performance characteristics of linear 32-, 64- and 128-element arrays of 50-, 60- and 75-μm-pixel bolometers on several detector lots. The infrared and thermal modeling accounting for the read-out properties and self-heating effect in bolometers resulted in improved designs and competitive NETD values of 80 mK on 50 μm pixels in a 160x128 format at standard frame rates and f-number of 1. In parallel, the TCR-to-1/f noise ratio and the mechanical design of the pixels were improved making poly-SiGe a good candidate for a low-cost uncooled thermal array. The technological CMOS-based process possesses an attractive balance between characteristics and price, and allows the micromachining of thin structures, less than 0.2 μm. The resistance and TCR non-uniformity with σ/μ better than 0.2% combined with 99.93% yield are demonstrated. The first lots of fully processed linear arrays have already come from the IMEC process line and the results of characterization are presented. Next year, the first linear and small 2D arrays will be introduced on the market.

Design and characterization of a prototype divertor viewing infrared video bolometer for NSTX-U

DOE PAGES

van Eden, G. G.; Reinke, M. L.; Peterson, B. J.; ...

2016-07-12

The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 μm thick, 9 × 7 cm 2 Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solvingmore » the 2D+time heat diffusion equation, using the foil’s calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. Here, the optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.« less

Design and characterization of a prototype divertor viewing infrared video bolometer for NSTX-U

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

Eden, G. G. van; Morgan, T. W.; Reinke, M. L.

The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 μm thick, 9 × 7 cm{sup 2} Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solvingmore » the 2D+time heat diffusion equation, using the foil’s calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. The optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.« less

Design and characterization of a prototype divertor viewing infrared video bolometer for NSTX-U

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

van Eden, G. G.; Reinke, M. L.; Peterson, B. J.

The InfraRed Video Bolometer (IRVB) is a powerful tool to measure radiated power in magnetically confined plasmas due to its ability to obtain 2D images of plasma emission using a technique that is compatible with the fusion nuclear environment. A prototype IRVB has been developed and installed on NSTX-U to view the lower divertor. The IRVB is a pinhole camera which images radiation from the plasma onto a 2.5 μm thick, 9 × 7 cm 2 Pt foil and monitors the resulting spatio-temporal temperature evolution using an IR camera. The power flux incident on the foil is calculated by solvingmore » the 2D+time heat diffusion equation, using the foil’s calibrated thermal properties. An optimized, high frame rate IRVB, is quantitatively compared to results from a resistive bolometer on the bench using a modulated 405 nm laser beam with variable power density and square wave modulation from 0.2 Hz to 250 Hz. The design of the NSTX-U system and benchtop characterization are presented where signal-to-noise ratios are assessed using three different IR cameras: FLIR A655sc, FLIR A6751sc, and SBF-161. The sensitivity of the IRVB equipped with the SBF-161 camera is found to be high enough to measure radiation features in the NSTX-U lower divertor as estimated using SOLPS modeling. Here, the optimized IRVB has a frame rate up to 50 Hz, high enough to distinguish radiation during edge-localized-modes (ELMs) from that between ELMs.« less

Light curves of flat-spectrum radio sources (Jenness+, 2010)

NASA Astrophysics Data System (ADS)

Jenness, T.; Robson, E. I.; Stevens, J. A.

2010-05-01

Calibrated data for 143 flat-spectrum extragalactic radio sources are presented at a wavelength of 850um covering a 5-yr period from 2000 April. The data, obtained at the James Clerk Maxwell Telescope using the Submillimetre Common-User Bolometer Array (SCUBA) camera in pointing mode, were analysed using an automated pipeline process based on the Observatory Reduction and Acquisition Control - Data Reduction (ORAC-DR) system. This paper describes the techniques used to analyse and calibrate the data, and presents the data base of results along with a representative sample of the better-sampled light curves. A re-analysis of previously published data from 1997 to 2000 is also presented. The combined catalogue, comprising 10493 flux density measurements, provides a unique and valuable resource for studies of extragalactic radio sources. (2 data files).

Enhanced performance of VOx-based bolometer using patterned gold black absorber

NASA Astrophysics Data System (ADS)

Smith, Evan M.; Panjwani, Deep; Ginn, James; Warren, Andrew; Long, Christopher; Figuieredo, Pedro; Smith, Christian; Perlstein, Joshua; Walter, Nick; Hirschmugl, Carol; Peale, Robert E.; Shelton, David J.

2015-06-01

Patterned highly absorbing gold black film has been selectively deposited on the active surfaces of a vanadium-oxide-based infrared bolometer array. Patterning by metal lift-off relies on protection of the fragile gold black with an evaporated oxide, which preserves gold black's near unity absorption. This patterned gold black also survives the dry-etch removal of the sacrificial polyimide used to fabricate the air-bridge bolometers. Infrared responsivity is substantially improved by the gold black coating without significantly increasing noise. The increase in the time constant caused by the additional mass of gold black is a modest 14%.

Novel Multiplexing Technique for Detector and Mixer Arrays

NASA Technical Reports Server (NTRS)

Karasik, Boris S.; McGrath, William R.

2001-01-01

Future submillimeter and far-infrared space telescopes will require large-format (many 1000's of elements) imaging detector arrays to perform state-of-the-art astronomical observations. A crucial issue related to a focal plane array is a readout scheme which is compatible with large numbers of cryogenically-cooled (typically < 1 K) detectors elements. When the number of elements becomes of the order of thousands, the physical layout for individual readout amplifiers becomes nearly impossible to realize for practical systems. Another important concern is the large number of wires leading to a 0.1-0.3 K platform. In the case of superconducting transition edge sensors (TES), a scheme for time-division multiplexing of SQUID read-out amplifiers has been recently demonstrated. In this scheme the number of SQUIDs is equal to the number (N) of the detectors, but only one SQUID is turned on at a time. The SQUIDs are connected in series in each column of the array, so the number of wires leading to the amplifiers can be reduced, but it is still of the order of N. Another approach uses a frequency domain multiplexing scheme of the bolometer array. The bolometers are biased with ac currents whose frequencies are individual for each element and are much higher than the bolometer bandwidth. The output signals are connected in series in a summing loop which is coupled to a single SQUID amplifier. The total number of channels depends on the ratio between the SQUID bandwidth and the bolometer bandwidth and can be at least 100 according to the authors. An important concern about this technique is a contribution of the out-of-band Johnson noise which multiplies by factor N(exp 1/2) for each frequency channel. We propose a novel solution for large format arrays based on the Hadamard transform coding technique which requires only one amplifier to read out the entire array of potentially many 1000's of elements and uses approximately 10 wires between the cold stage and room temperature electronics. This can significantly reduce the complexity of the readout circuits.

First Astronomical Use of Multiplexed Transition Edge Sensor Bolometers

NASA Technical Reports Server (NTRS)

Staguhn, J. G.; Ames, T. A.; Benford, D. J.; Chervenak, J. A.; Grossman, E. N.; Irwin, K. D.; Khan, S. A.; Maffei, B.; Moseley, S. H.; Pajot, F.

2004-01-01

We present performance results based on the first astronomical use of multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer that achieved first light in June 2001 at the Caltech Submillimeter Observatory (CSO). FIBRE's detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing 5 orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering Delta lambda/lambda = 1/7 at a resolution of delta lambda/lambda approx. 1/1200 can be acquired. This spectral resolution is sufficient to resolve Doppler-broadened line emission from external galaxies. FIBRE operates in the 350 m and 450 m bands. These bands cover line emission from the important star formation tracers neutral carbon (CI) and carbon monoxide (CO). We have verified that the multiplexed bolometers are photon noise limited even with the low power present in moderate resolution spectrometry.

First Astronomical Use Of Multiplexed Transition Edge Bolometers

NASA Technical Reports Server (NTRS)

Benford, D. J.; Chervenak, J. A.; Grossman, E. N.; Irwin, K. D.; DeKotwara, S. A.; Maffei, B.; Moseley, S. H.; Pajot, F.; Phillips, T. G.; Reintsema, C. D.

2001-01-01

We present performance results based on the first astronomical use of multiplexed superconducting bolometers. The Fabry-Perot Interferometer Bolometer Research Experiment (FIBRE) is a broadband submillimeter spectrometer that achieved first light in June 2001 at the Caltech Submillimeter Observatory (CSO). FIBRE's detectors are superconducting transition edge sensor (TES) bolometers read out by a SQUID multiplexer. The Fabry-Perot uses a low resolution grating to order sort the incoming light. A linear bolometer array consisting of 16 elements detects this dispersed light, capturing five orders simultaneously from one position on the sky. With tuning of the Fabry-Perot over one free spectral range, a spectrum covering delta-lamda/lamda = 1/7 at a resolution of delta-lamda/lamda = 1/1200 can be acquired. This spectral resolution is sufficient to resolve doppler broadened line emission from external galaxies. FIBRE operates in the 350 micrometer and 450 micrometer bands. These bands cover line emission from the important PDR tracers neutral carbon [CI] and carbon monoxide (CO). We have verified that the multiplexed bolometers are photon noise limited even with the low power present in moderate resolution spectrometry.

Development of imaging bolometers for magnetic fusion reactors (invited)

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

Peterson, Byron J.; Parchamy, Homaira; Ashikawa, Naoko

2008-10-15

Imaging bolometers utilize an infrared (IR) video camera to measure the change in temperature of a thin foil exposed to the plasma radiation, thereby avoiding the risks of conventional resistive bolometers related to electric cabling and vacuum feedthroughs in a reactor environment. A prototype of the IR imaging video bolometer (IRVB) has been installed and operated on the JT-60U tokamak demonstrating its applicability to a reactor environment and its ability to provide two-dimensional measurements of the radiation emissivity in a poloidal cross section. In this paper we review this development and present the first results of an upgraded version ofmore » this IRVB on JT-60U. This upgrade utilizes a state-of-the-art IR camera (FLIR/Indigo Phoenix-InSb) (3-5 {mu}m, 256x360 pixels, 345 Hz, 11 mK) mounted in a neutron/gamma/magnetic shield behind a 3.6 m IR periscope consisting of CaF{sub 2} optics and an aluminum mirror. The IRVB foil is 7 cmx9 cmx5 {mu}m tantalum. A noise equivalent power density of 300 {mu}W/cm{sup 2} is achieved with 40x24 channels and a time response of 10 ms or 23 {mu}W/cm{sup 2} for 16x12 channels and a time response of 33 ms, which is 30 times better than the previous version of the IRVB on JT-60U.« less

Three-meter balloon-borne telescope

NASA Technical Reports Server (NTRS)

Hoffmann, William F.; Fazio, G. G.; Harper, D. A.

1988-01-01

The Three-Meter Balloon-Borne Telescope is planned as a general purpose facility for making far-infrared and submillimeter astronomical observations from the stratosphere. It will operate throughout the spectral range 30 microns to 1 millimeter which is largely obscurred from the ground. The design is an f/13.5 Cassegrain telescope with an f/1.33 3-meter primary mirror supported with a 3-axis gimbal and stabilization system. The overall structure is 8.0 m high by 5.5 m in width by 4.0 m in depth and weighs 2000 kg. This low weight is achieved through the use of an ultra lightweight primary mirror of composite construction. Pointing and stabilization are achieved with television monitoring of the star field, flex-pivot bearing supports, gyroscopes, and magnetically levitated reaction wheels. Two instruments will be carried on each flight; generally a photometric camera and a spectrometer. A 64-element bolometer array photometric camera operating from 30 to 300 microns is planned as part of the facility. Additional instruments will be derived from KAO and other development programs.

The HERSCHEL/PACS early Data Products

NASA Astrophysics Data System (ADS)

Wieprecht, E.; Wetzstein, M.; Huygen, R.; Vandenbussche, B.; De Meester, W.

2006-07-01

ESA's Herschel Space Observatory to be launched in 2007, is the first space observatory covering the full far-infrared and submillimeter wavelength range (60 - 670 microns). The Photodetector Array Camera & Spectrometer (PACS) is one of the three science instruments. It contains two Ge:Ga photoconductor arrays and two bolometer arrays to perform imaging line spectroscopy and imaging photometry in the 60 - 210 micron wavelength band. The HERSCHEL ground segment (Herschel Common Science System - HCSS) is implemented using JAVA technology and written in a common effort by the HERSCHEL Science Center and the three instrument teams. The PACS Common Software System (PCSS) is based on the HCSS and used for the online and offline analysis of PACS data. For telemetry bandwidth reasons PACS science data are partially processed on board, compressed, cut into telemetry packets and transmitted to the ground. These steps are instrument mode dependent. We will present the software model which allows to reverse the discrete on board processing steps and evaluate the data. After decompression and reconstruction the detector data and instrument status information are organized in two main PACS Products. The design of these JAVA classes considers the individual sampling rates, data formats, memory and performance optimization aspects and comfortable user interfaces.

Optical and IR applications in astronomy and astrophysics

NASA Astrophysics Data System (ADS)

McLean, Ian S.

2009-06-01

The set comprising silicon charge-coupled devices, low band-gap infrared arrays and bolometer arrays provide astronomers with position-sensitive photon detectors from the X-ray to the sub-mm. In recent years the most significant advances have occurred in the near-infrared part of the spectrum because not only have the detector formats caught up with those of charge-coupled device (CCDs) but also because the advent of adaptive optics (AO) has meant that the very largest telescopes can achieve their diffraction limit in the near-infrared. Thus infrared cameras, spectrometers and hybrid instruments that measure spatial and spectral information simultaneously are now commanding the greatest attention on telescopes from 6.5 to 10 m in effective aperture. Scientific applications of these new infrared instruments span everything from the search for nearby solar systems to the orbital motions of stars about the massive black hole at the center of the Milky Way, and studies of the first galaxies to form in the high redshift Universe. Background, principles and applications of infrared array detectors to astronomy and astrophysics will be discussed with particular emphasis on work at the W.M. Keck 10-m telescope on Mauna Kea, Hawaii.

Spectroscopic Capabilities and Possibilities of the Far Infrared and Submillimeter Telescope Mission

NASA Technical Reports Server (NTRS)

Pearson, J. C.

2000-01-01

The Far Infrared and Submillimeter Telescope (FIRST) mission is the fourth European Space Agency corner stone mission. FIRST will be an observatory with a passively cooled (80 Kelvin) 3.5 meter class telescope and three cryogenic instruments covering the 670 to 80 mm spectral region. The mission is slated for a 4.5 year operational lifetime in an L2 orbit. It will share an Arian 5 launch with PLANCK in early 2007. The three payload instruments include the Spectral and Photometric Imaging Receiver (SPIRE), which is a bolometer array with Martin-Puplett FTS for 200-670 microns, the Photoconductor Array Camera and Spectrometer (PACS), which is a photoconductor array with a grating spectrometer for 80-210 microns and the Heterodyne Instrument for FIRST (HIFI), which is a series of seven heterodyne receivers covering 480-1250 GHz and portions of 1410-1910 GHz and 2400-2700 GHz. FIRST will make many detailed spectral surveys of a wide variety of objects previously obscured by the atmosphere and in regions of the spectrum seldom used for astronomical observations, With all of the spectroscopic capability on FIRST a great deal of laboratory spectroscopic support will be needed for accurate interpretation of the spectral data.

Broadband Direct Detection Submillimeter Spectrometer with Multiplexed Superconducting Transition Edge Thermometer Bolometers

NASA Technical Reports Server (NTRS)

Benford, D. J.; Ames, T. A.; Chervenak, J. A.; Moseley, S. H.; Shafer, R. A.; Staguhn, J. G.; Voellmer, G. M.; Pajot, F.; Rioux, C.; Phillips, T. G.;

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

Cushman, Jeremy S.; Dally, Adam; Davis, Christopher J.

The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale cryogenic experiment designed to search for neutrinoless double-beta decay of 130Te and other rare events. The CUORE detector consists of 988 TeO 2 bolometers operated underground at 10 mK in a dilution refrigerator at the Laboratori Nazionali del Gran Sasso. Candidate events are identified through a precise measurement of their energy. The absolute energy response of the detectors is established by the regular calibration of each individual bolometer using gamma sources. The close-packed configuration of the CUORE bolometer array combined with the extensive shielding surrounding the detectors requires themore » placement of calibration sources within the array itself. The CUORE Detector Calibration System is designed to insert radioactive sources into and remove them from the cryostat while respecting the stringent heat load, radiopurity, and operational requirements of the experiment. In conclusion, this paper describes the design, commissioning, and performance of this novel source calibration deployment system for ultra-low-temperature environments.« less

Electromagnetic Considerations for Planar Bolometer Arrays in the Single Mode Limit

NASA Technical Reports Server (NTRS)

Wollack, Edward J.; Chuss, David T.; Moseley, Samuel

2006-01-01

Filled arrays of planar bolometers are finding astronomical applications at wavelengths as long as several millimeters. In an effort to keep focal planes to a reasonable size while maintaining large numbers of detectors, a common strategy is to push these arrays to operate close to or at the single mode limit. Doing so introduces several new challenges that are not experienced in the multi-mode case of far-infrared detectors having similar pixel sizes. First, diffractive effects of the pixels themselves are no longer insignificant and will ultimately contribute to the resolution limit of the optical system in which they reside. We use the method of Withlngton et al. (2003) to model the polarized diffraction in this limit. Second, it is necessary to re-examine the coupling between the radiation and the absorbing element that is thermally connected to the bolometers. The small f-numbers that are often employed to make use of large focal planes makes backshort construction problematic. We introduce a new strategy to increase detector efficiency that uses an antireflective layer on the front side of the detector array. In addition, typical methods for stray light control that rely on multiple reflections in a lossy medium fail due to physical size constraints. For this application, we find that resonant absorbers are a more effective strategy that can be implemented in the space available.

Bolometric Array Detectors for Space-Borne Astronomy

NASA Technical Reports Server (NTRS)

Lange, Andrew E.

2000-01-01

Funding from the NASA Innovative Research Grant was used to develop bolometric detectors. As described in the proposal, silicon nitride micromesh ('spider-web') absorbers had been demonstrated at U.C. Berkeley but not developed to be flight-worthy devices. We proceeded to first fabricate bolometers with Neutron Transmutation Doped (NTD) Ge thermistors that demonstrated high optical coupling (Church et al. 1996) and were developed for a ground-based millimeter-wave receiver (Mauskopf et al. 1997). The next generation of devices used In bump-bonded thermistors to achieve devices with performance product NEP*sqrt(tau) = 3e - 18 j at 300 mK, demonstrating a full order of magnitude improvement over pervious devices. These devices achieved an NEP = 1e-18 W/rtHz (Murray et al. 1996) as promised in the proposal. Sensitivities as good as 1e - 19 W/rtHz appear achievable with the silicon nitride architecture (Bock et al. 1997). Finally, arrays of micromesh bolometers were shown to be feasible in the last year of the program by etching a large number of devices on a single silicon wafer (75 mm). Full arrays were subsequently demonstrated for selection on the ESA/NASA Far-Infrared Space Telescope (FIRST) in competition with detectors provided by CEA in France and GSFC in the US Micromesh bolometer arrays are now baselined for both the ESA/NASA Planck and FIRST missions.

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

Thompson, M. C., E-mail: mthompson@trialphaenergy.com; Gota, H.; Putvinski, S.

The C-2U experiment at Tri Alpha Energy studies the evolution of field-reversed configuration (FRC) plasmas sustained by neutral beam injection. Data on the FRC plasma performance are provided by a comprehensive suite of diagnostics that includes magnetic sensors, interferometry, Thomson scattering, spectroscopy, bolometry, reflectometry, neutral particle analyzers, and fusion product detectors. While many of these diagnostic systems were inherited from the preceding experiment C-2, C-2U has a variety of new and upgraded diagnostic systems: multi-chord far-infrared polarimetry, multiple fast imaging cameras with selectable atomic line filters, proton detector arrays, and 100 channel bolometer units capable of observing multiple regions ofmore » the spectrum simultaneously. In addition, extensive ongoing work focuses on advanced methods of measuring separatrix shape and plasma current profile that will facilitate equilibrium reconstruction and active control of the FRC plasma.« less

Superconducting noise bolometer with microwave bias and readout for array applications

NASA Astrophysics Data System (ADS)

Kuzmin, A. A.; Semenov, A. D.; Shitov, S. V.; Merker, M.; Wuensch, S. H.; Ustinov, A. V.; Siegel, M.

2017-07-01

We present a superconducting noise bolometer for terahertz radiation, which is suitable for large-format arrays. It is based on an antenna-coupled superconducting micro-bridge embedded in a high-quality factor superconducting resonator for a microwave bias and readout with frequency-division multiplexing in the GHz range. The micro-bridge is kept below its critical temperature and biased with a microwave current of slightly lower amplitude than the critical current of the micro-bridge. The response of the detector is the rate of superconducting fluctuations, which depends exponentially on the concentration of quasiparticles in the micro-bridge. Excess quasiparticles are generated by an incident THz signal. Since the quasiparticle lifetime increases exponentially at lower operation temperature, the noise equivalent power rapidly decreases. This approach allows for large arrays of noise bolometers operating above 1 K with sensitivity, limited by 300-K background noise. Moreover, the response of the bolometer always dominates the noise of the readout due to relatively large amplitude of the bias current. We performed a feasibility study on a proof-of-concept device with a 1.0 × 0.5 μm2 micro-bridge from a 9-nm thin Nb film on a sapphire substrate. Having a critical temperature of 5.8 K, it operates at 4.2 K and is biased at the frequency 5.6 GHz. For the quasioptical input at 0.65 THz, we measured the noise equivalent power ≈3 × 10-12 W/Hz1/2, which is close to expectations for this particular device in the noise-response regime.

TES development for a frequency selective bolometer camera.

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

Datesman, A. M.; Downes, T. P.; Perera, T. A.

2009-06-01

We discuss the development, at Argonne National Laboratory (ANL), of a four-pixel camera with four spectral channels centered at 150, 220, 270, and 360 GHz. The scientific motivation involves photometry of distant dusty galaxies located by Spitzer and SCUBA, as well as the study of other millimeter-wave sources such as ultra-luminous infrared galaxies, the Sunyaev-Zeldovich effect in clusters, and galactic dust. The camera incorporates Frequency Selective Bolometer (FSB) and superconducting Transition-Edge Sensor (TES) technology. The current generation of TES devices we examine utilizes proximity effect superconducting bilayers of Mo/Au, Ti, or Ti/Au as TESs, located along with frequency selective absorbingmore » structures on silicon nitride membranes. The detector incorporates lithographically patterned structures designed to address both TES device stability and detector thermal transport concerns. The membrane is not perforated, resulting in a detector which is comparatively robust mechanically. In this paper, we report on the development of the superconducting bilayer TES technology, the design and testing of the detector thermal transport and device stability control structures, optical and thermal test results, and the use of new materials.« less

Indium Hybridization of Large Format TES Bolometer Arrays to Readout Multiplexers for Far-Infrared Astronomy

NASA Technical Reports Server (NTRS)

Miller, Timothy M.; Costen, Nick; Allen, Christine

2007-01-01

The advance of new detector technologies combined with enhanced fabrication methods has resulted in an increase in development of large format arrays. The next generation of scientific instruments will utilize detectors containing hundreds to thousands of elements providing a more efficient means to conduct large area sky surveys. Some notable detectors include a 32x32 x-ray microcalorimeter for Constellation-X, an infrared bolometer called SAFIRE to fly on the airborne observatory SOFIA, and the sub-millimeter bolometer SCUBA-2 to be deployed at the JCMT which will use more than 10,000 elements for two colors, each color using four 32x40 arrays. Of these detectors, SCUBA-2 is farthest along in development and uses indium hybridization to multiplexers for readout of the large number of elements, a technology that will be required to enable the next generation of large format arrays. Our current efforts in working toward large format arrays have produced GISMO, the Goddard IRAM Superconducting 2-Millimeter observer. GISMO is a far infrared instrument to be field tested later this year at the IRAM 30 meter telescope in Spain. GISMO utilizes transition edge sensor (TES) technology in an 8x16 filled array format that allows for typical fan-out wiring and wire-bonding to four 1x32 NIST multiplexers. GISMO'S electrical wiring is routed along the tops of 30 micron walls which also serve as the mechanical framework for the array. This architecture works well for the 128 element array, but is approaching the limit for routing the necessary wires along the surface while maintaining a high fill factor. Larger format arrays will benefit greatly from making electrical connections through the wafer to the backside, where they can be hybridized to a read-out substrate tailored to handling the wiring scheme. The next generation array we are developing is a 32x40 element array on a pitch of 1135 microns that conforms to the NIST multiplexer, already developed for the SCUBA-2 instrument This architecture will utilize electrical connections that route from the TES to the support frame and through the wafer. The detector chip will then be hybridized to the NIST multiplexer via indium bump bonding. In our development scheme we are using substrates that allow for diagnostic testing of electrical continuity across the entire array and we are testing our process to minimize or eliminate any contact resistance at metal interfaces. Our goal is hybridizing a fully functional 32x40 array of TES bolometers to a NIST multiplexer. The following work presents our current progress toward enabling this technology.

Comparison of Thermal Detector Arrays for Off-Axis THz Holography and Real-Time THz Imaging

PubMed Central

Hack, Erwin; Valzania, Lorenzo; Gäumann, Gregory; Shalaby, Mostafa; Hauri, Christoph P.; Zolliker, Peter

2016-01-01

In terahertz (THz) materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8–14 μm wavelength range, but are based on different absorber materials (i) vanadium oxide; (ii) amorphous silicon; (iii) a micro-bolometer array optimized for recording THz radiation based on silicon nitride; and (iv) a pyroelectric array detector for THz beam profile measurements. THz wavelengths of 96.5 μm, 118.8 μm, and 393.6 μm from a powerful far infrared laser were used to assess the technical performance in terms of signal to noise ratio, detector response and detectivity. The usefulness of the detectors for beam profiling and digital holography is assessed. Finally, the potential and limitation for real-time digital holography are discussed. PMID:26861341

Comparison of Thermal Detector Arrays for Off-Axis THz Holography and Real-Time THz Imaging.

PubMed

Hack, Erwin; Valzania, Lorenzo; Gäumann, Gregory; Shalaby, Mostafa; Hauri, Christoph P; Zolliker, Peter

2016-02-06

In terahertz (THz) materials science, imaging by scanning prevails when low power THz sources are used. However, the application of array detectors operating with high power THz sources is increasingly reported. We compare the imaging properties of four different array detectors that are able to record THz radiation directly. Two micro-bolometer arrays are designed for infrared imaging in the 8-14 μm wavelength range, but are based on different absorber materials (i) vanadium oxide; (ii) amorphous silicon; (iii) a micro-bolometer array optimized for recording THz radiation based on silicon nitride; and (iv) a pyroelectric array detector for THz beam profile measurements. THz wavelengths of 96.5 μm, 118.8 μm, and 393.6 μm from a powerful far infrared laser were used to assess the technical performance in terms of signal to noise ratio, detector response and detectivity. The usefulness of the detectors for beam profiling and digital holography is assessed. Finally, the potential and limitation for real-time digital holography are discussed.

Strong Electron Self-Cooling in the Cold-Electron Bolometers Designed for CMB Measurements

NASA Astrophysics Data System (ADS)

Kuzmin, L. S.; Pankratov, A. L.; Gordeeva, A. V.; Zbrozhek, V. O.; Revin, L. S.; Shamporov, V. A.; Masi, S.; de Bernardis, P.

2018-03-01

We have realized cold-electron bolometers (CEB) with direct electron self-cooling of the nanoabsorber by SIN (Superconductor-Insulator-Normal metal) tunnel junctions. This electron self-cooling acts as a strong negative electrothermal feedback, improving noise and dynamic properties. Due to this cooling the photon-noise-limited operation of CEBs was realized in array of bolometers developed for the 345 GHz channel of the OLIMPO Balloon Telescope in the power range from 10 pW to 20 pW at phonon temperature Tph =310 mK. The negative electrothermal feedback in CEB is analogous to TES but instead of artificial heating we use cooling of the absorber. The high efficiency of the electron self-cooling to Te =100 mK without power load and to Te=160 mK under power load is achieved by: - a very small volume of the nanoabsorber (0.02 μm3) and a large area of the SIN tunnel junctions, - effective removal of hot quasiparticles by arranging double stock at both sides of the junctions and close position of the normal metal traps, - self-protection of the 2D array of CEBs against interferences by dividing them between N series CEBs (for voltage interferences) and M parallel CEBs (for current interferences), - suppression of Andreev reflection by a thin layer of Fe in the AlFe absorber. As a result even under high power load the CEBs are working at electron temperature Te less than Tph . To our knowledge, there is no analogue in the bolometers technology in the world for bolometers working at electron temperature colder than phonon temperature.

Mechanical Design and Development of TES Bolometer Detector Arrays for the Advanced ACTPol Experiment

NASA Technical Reports Server (NTRS)

Ward, Jonathan T.; Austermann, Jason; Beall, James A.; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark J.; Duff, Shannon M.; Gallardo, Patricio M.; Henderson, Shawn W.; Ho, Shuay-Pwu Patty;

Mechanical designs and development of TES bolometer detector arrays for the Advanced ACTPol experiment

NASA Astrophysics Data System (ADS)

Ward, Jonathan T.; Austermann, Jason; Beall, James A.; Choi, Steve K.; Crowley, Kevin T.; Devlin, Mark J.; Duff, Shannon M.; Gallardo, Patricio A.; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; Hilton, Gene; Hubmayr, Johannes; Khavari, Niloufar; Klein, Jeffrey; Koopman, Brian J.; Li, Dale; McMahon, Jeffrey; Mumby, Grace; Nati, Federico; Niemack, Michael D.; Page, Lyman A.; Salatino, Maria; Schillaci, Alessandro; Schmitt, Benjamin L.; Simon, Sara M.; Staggs, Suzanne T.; Thornton, Robert; Ullom, Joel N.; Vavagiakis, Eve M.; Wollack, Edward J.

2016-07-01

The next generation Advanced ACTPol (AdvACT) experiment is currently underway and will consist of four Transition Edge Sensor (TES) bolometer arrays, with three operating together, totaling 5800 detectors on the sky. Building on experience gained with the ACTPol detector arrays, AdvACT will utilize various new technologies, including 150 mm detector wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors includes a feedhorn array of stacked silicon wafers which form a spline profile leading to each pixel. This is then followed by a waveguide interface plate, detector wafer, back short cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured from high purity copper and then gold plated. In addition to the detector array assembly, the array package also encloses cryogenic readout electronics. We present the full mechanical design of the AdvACT high frequency (HF) detector array package along with a detailed look at the detector array stack assemblies. This experiment will also make use of extensive hardware and software previously developed for ACT, which will be modified to incorporate the new AdvACT instruments. Therefore, we discuss the integration of all AdvACT arrays with pre-existing ACTPol infrastructure.

Mapping TES Aerobreaking Data of The Martian Polar Caps

NASA Astrophysics Data System (ADS)

Altunaiji, E. S.; Edwards, C. S.; Smith, M. D.; AlShamsi, M. R.; AlJanaahi, A. A.

2016-12-01

The purpose of this paper is to create maps of the north and south Mars polar caps using Thermal Emission Spectrometer (TES) aerobreaking surface temperature data in south and north as well as Lambert albedo data in the south. TES is an instrument on board the Mars Global Surveyor (MGS) spacecraft. It has six detectors arranged in a 2x3 array with a nominal spot size of 3 × 6 km; however, given the elliptical nature of the orbit during aerobreaking the footprint can be significantly larger (10s of km), especially over the southern hemisphere. TES is a Fourier transform infrared spectrometer designed to study the Martian surface and atmosphere using thermal infrared emission spectroscopy. It is composed of 2 separate channels, a broadband visible/near-infrared bolometer and hyperspectral thermal infrared spectrometer with a broadband thermal infrared bolometer. TES aerobraking spectra were taken between Mars Year 23, Ls=180° and Mars Year 24, Ls=30°. To determine the footprint location on the surface, geometry is calculated using the Spacecraft Planet Instrument Camera Matrix and Event (SPICE) Toolkit. These data were then binned and mapped to surface in polar stereographic projection. While some early studies focused on these data, we have expanded upon the ranges, generated time-/seasonally-binned data, and re-examined this largely underutilized set of data from TES ultimately extending the record of polar science on Mars.

Large-format 17μm high-end VOx μ-bolometer infrared detector

NASA Astrophysics Data System (ADS)

Mizrahi, U.; Argaman, N.; Elkind, S.; Giladi, A.; Hirsh, Y.; Labilov, M.; Pivnik, I.; Shiloah, N.; Singer, M.; Tuito, A.; Ben-Ezra, M.; Shtrichman, I.

2013-06-01

Long range sights and targeting systems require a combination of high spatial resolution, low temporal NETD, and wide field of view. For practical electro-optical systems it is hard to support these constraints simultaneously. Moreover, achieving these needs with the relatively low-cost Uncooled μ-Bolometer technology is a major challenge in the design and implementation of both the bolometer pixel and the Readout Integrated Circuit (ROIC). In this work we present measured results from a new, large format (1024×768) detector array, with 17μm pitch. This detector meets the demands of a typical armored vehicle sight with its high resolution and large format, together with low NETD of better than 35mK (at F/1, 30Hz). We estimate a Recognition Range for a NATO target of better than 4 km at all relevant atmospheric conditions, which is better than standard 2nd generation scanning array cooled detector. A new design of the detector package enables improved stability of the Non-Uniformity Correction (NUC) to environmental temperature drifts.

Stray light suppression in the Goddard IRAM 2-Millimeter Observer (GISMO)

NASA Astrophysics Data System (ADS)

Sharp, E. H.; Benford, D. J.; Fixsen, D. J.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

2012-09-01

The Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) is an 8x16 Transition Edge Sensor (TES) array of bolometers built as a pathfinder for TES detector development efforts at NASA Goddard Space Flight Center. GISMO has been used annually at the Institut de Radioastronomie Millimétrique (IRAM) 30 meter telescope since 2007 under engineering time and was opened in the spring of 2012 to the general astronomical community. The spring deployment provided an opportunity to modify elements of the room temperature optics before moving the instrument to its new permanent position in the telescope receiver cabin. This allowed for the possibility to extend the cryostat, introduce improved cold baffling and thus further optimize the stray light performance for final astronomical use of the instrument, which has been completed and validated. We will demonstrate and discuss several of the methods used to quantify and limit the influence of stray light in the GISMO camera.

Stray Light Suppression in the Goddard IRAM 2-Millimeter Observer (GISMO)

NASA Technical Reports Server (NTRS)

Sharp, E. H.; Benford, D. J.; Fixsen, D. J.; Moseley, S. H.; Staguhn, J. G.; Wollack, E. J.

2012-01-01

The Goddard-IRAM Superconducting 2 Millimeter Observer (GISMO) is an 8xl6 Transition Edge Sensor (TES) array of bolometers built as a pathfinder for TES detector development efforts at NASA Goddard Space Flight Center. GISMO has been used annually at the Institut de Radioastronomie Millimetrique (IRAM) 30 meter telescope since 2007 under engineering time and was opened in the spring of 2012 to the general astronomical community. The spring deployment provided an opportunity to modify elements of the room temperature optics before moving the instrument to its new permanent position in the telescope receiver cabin. This allowed for the possibility to extend the cryostat, introduce improved cold baffling and thus further optimize the stray light performance for final astronomical use of the instrument, which has been completed and validated. We will demonstrate and discuss several of the methods used to quantify and limit the influence of stray light in the GISMO camera.

Observations of flat-spectrum radio sources at λ850μm from the James Clerk Maxwell Telescope II. April 2000 to June 2005

NASA Astrophysics Data System (ADS)

Jenness, T.; Robson, E. I.; Stevens, J. A.

2010-01-01

Calibrated data for 143 flat-spectrum extragalactic radio sources are presented at a wavelength of 850μm covering a 5-yr period from 2000 April. The data, obtained at the James Clerk Maxwell Telescope using the Submillimetre Common-User Bolometer Array (SCUBA) camera in pointing mode, were analysed using an automated pipeline process based on the Observatory Reduction and Acquisition Control - Data Reduction (ORAC-DR) system. This paper describes the techniques used to analyse and calibrate the data, and presents the data base of results along with a representative sample of the better-sampled light curves. A re-analysis of previously published data from 1997 to 2000 is also presented. The combined catalogue, comprising 10493 flux density measurements, provides a unique and valuable resource for studies of extragalactic radio sources.

Proceedings of the Second Infrared Detector Technology Workshop

NASA Technical Reports Server (NTRS)

Mccreight, C. R. (Compiler)

1986-01-01

The workshop focused on infrared detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers are organized into the following categories: discrete infrared detectors and readout electronics; advanced bolometers; intrinsic integrated infrared arrays; and extrinsic integrated infrared arrays. Status reports on the Space Infrared Telescope Facility (SIRTF) and Infrared Space Observatory (ISO) programs are also included.

Status and Integrated Focal Plane Characterization of Simons Array - Cosmic Microwave Background Polarimetry Experiment

NASA Astrophysics Data System (ADS)

Roberts, Hayley; POLARBEAR

2018-06-01

Simons Array is a cosmic microwave background (CMB) polarization experiment located at 5,200 meter altitude site in the Atacama desert in Chile. The science goals of the Simons Array are to characterize the CMB B-mode signal from gravitational lensing, and search for B-mode polarization generated from inflationary gravitational waves.In 2012, POLARBEAR-1 (PB-1) began observations and the POLARBEAR team has published the first measurements of non-zero polarization B-mode polarization angular power spectrum where gravitational lensing of CMB is the dominant signal.POLARBEAR-2A (PB-2A), the first of three receivers of Simons Array, will have 7,588 polarization sensitive Transition Edge Sensor (TES) bolometers with frequencies 90 GHz and 150 GHz. This represents a factor of 6 increase in detector count compared to PB-1. Once Simons Array is fully deployed, the focal plane array will consist 22,764 TES bolometers across 90 GHz, 150 GHz, 220 GHz, and 270 GHz with a projected instantaneous sensitivity of 2.5 µK√s. Here we present the status of PB-2A and characterization of the integrated focal plane to be deployed summer of 2018.

Progress on the FDM Development at SRON: Toward 160 Pixels

NASA Astrophysics Data System (ADS)

den Hartog, R. H.; Bruijn, M. P.; Clenet, A.; Gottardi, L.; Hijmering, R.; Jackson, B. D.; van der Kuur, J.; van Leeuwen, B. J.; van der Linden, A. J.; van Loon, D.; Nieuwenhuizen, A.; Ridder, M.; van Winden, P.

2014-08-01

SRON is developing the electronic read-out for arrays of transition edge sensors using frequency domain multiplexing in combination with base-band feedback. The astronomical applications of this system are the read-out of soft X-ray micro-calorimeters in a potential instrument on the European X-ray mission-under-study Athena+ and far-IR bolometers for the Safari instrument on the Japanese mission SPICA. In this paper we demonstrate the simultaneous read-out of 38 bolometer pixels at a 12 aW/Hz dark NEP level. The stability of the read-out is assessed over 400 s. time spans. Although some 1/f noise is present, there are several bolometers for which 1/f-free read-out can be demonstrated.

Challenges, constraints, and results of lens design for 17 micron-bolometer focal plane arrays in 8-12 micron waveband

NASA Astrophysics Data System (ADS)

Schuster, Norbert; Franks, John

2011-06-01

In the 8-12 micron waveband Focal Plane Arrays (FPA) are available with a 17 micron pixel pitch in different arrays sizes (e.g. 512 x 480 pixels and 320 x 240 pixels) and with excellent electrical properties. Many applications become possible using this new type of IR-detector which will become the future standard in uncooled technology. Lenses with an f-number faster than f/1.5 minimize the diffraction impact on the spatial resolution and guarantee a high thermal resolution for uncooled cameras. Both effects will be quantified. The distinction between Traditional f-number (TF) and Radiometric f-number (RF) is discussed. Lenses with different focal lengths are required for applications in a variety of markets. They are classified by their Horizontal field of view (HFOV). Respecting the requirements for high volume markets, several two lens solutions will be discussed. A commonly accepted parameter of spatial resolution is the Modulation Transfer Function (MTF)-value at the Nyquist frequency of the detector (here 30cy/mm). This parameter of resolution will be presented versus field of view. Wide Angle and Super Wide Angle lenses are susceptible to low relative illumination in the corner of the detector. Measures to reduce this drop to an acceptable value are presented.

Polarization measurements made on LFRA and OASIS emitter arrays

NASA Astrophysics Data System (ADS)

Geske, Jon; Sparkman, Kevin; Oleson, Jim; Laveigne, Joe; Sieglinger, Breck; Marlow, Steve; Lowry, Heard; Burns, James

2008-04-01

Polarization is increasingly being considered as a method of discrimination in passive sensing applications. In this paper the degree of polarization of the thermal emission from the emitter arrays of two new Santa Barbara Infrared (SBIR) micro-bolometer resistor array scene projectors was characterized at ambient temperature and at 77 K. The emitter arrays characterized were from the Large Format Resistive Array (LFRA) and the Optimized Arrays for Space-Background Infrared Simulation (OASIS) scene projectors. This paper reports the results of this testing.

Overview of APEX Capabilities

NASA Astrophysics Data System (ADS)

De Breuck, Carlos

2018-03-01

The APEX telescope has a range instruments that are highly complementary to ALMA. The single pixel heterodyne receivers cover virtually all atmospheric windows from 157 GHz to above 1 THz, augmented by 7-pixel heterodyne arrays covering 280 to 950 GHz, while the bolometer arrays cover the 870, 450 and 350µm bands.

Neutron Transmutation Doped (NTD) germanium thermistors for sub-mm bolometer applications

NASA Technical Reports Server (NTRS)

Haller, E. E.; Itoh, K. M.; Beeman, J. W.

1996-01-01

Recent advances in the development of neutron transmutation doped (NTD) semiconductor thermistors fabricated from natural and controlled isotopic composition germanium are reported. The near ideal doping uniformity that can be achieved with the NTD process, the device simplicity of NTD Ge thermistors and the high performance of cooled junction field effect transistor preamplifiers led to the widespread acceptance of these thermal sensors in ground-based, airborne and spaceborne radio telescopes. These features made possible the development of efficient bolometer arrays.

Bloch oscillating transistor as the readout element for hot electron bolometers

NASA Astrophysics Data System (ADS)

Hassel, Juha; Seppä, Heikki; Lindell, Rene; Hakonen, Pertti

2004-10-01

In this paper we analyse the properties of the Bloch oscillating transistor as a preamplifier in cryogenic devices. We consider here especially the readout of hot electron bolometers (HEBs) based on Normal-Superconductor-Insulator tunnel junctions, but the results also apply more generally. We show that one can get an equivalent noise voltage below 1 nV/√Hz with a single BOT. By using N BOTs in a parallel array configuration, a further reduction by factor √N may be achieved.

Experimental study of a SINIS detector response time at 350 GHz signal frequency

NASA Astrophysics Data System (ADS)

Lemzyakov, S.; Tarasov, M.; Mahashabde, S.; Yusupov, R.; Kuzmin, L.; Edelman, V.

2018-03-01

Response time constant of a SINIS bolometer integrated in an annular ring antenna was measured at a bath temperature of 100 mK. Samples comprising superconducting aluminium electrodes and normal-metal Al/Fe strip connected to electrodes via tunnel junctions were fabricated on oxidized Si substrate using shadow evaporation. The bolometer was illuminated by a fast black-body radiation source through a band-pass filter centered at 350 GHz with a passband of 7 GHz. Radiation source is a thin NiCr film on sapphire substrate. For rectangular 10÷100 μs current pulse the radiation front edge was rather sharp due to low thermal capacitance of NiCr film and low thermal conductivity of substrate at temperatures in the range 1-4 K. The rise time of the response was ~1-10 μs. This time presumably is limited by technical reasons: high dynamic resistance of series array of bolometers and capacitance of a long twisted pair wiring from SINIS bolometer to a room-temperature amplifier.

Auxiliary Components for Kilopixel Transition Edge Sensor Arrays

NASA Technical Reports Server (NTRS)

Brown, Ari-David; Chervenak, James A.; Chuss, David; Hilton Gene C.; Mikula, Vilem; Henry, ROss; Wollack, Edward; Zhao, Yue

2007-01-01

We have fabricated transition edge sensor bolometer focal plane arrays sensitive to mm-submillimeter (0.1-3 THz) radiation for the Atacama Cosmology Telescope (ACT), which will probe the cosmic microwave background at 0.147,0.215, and 0.279 GHz. Central to the performance of these bolometers is a set of auxiliary resistive components. Here we discuss shunt resistors, which allow for tight optimization of bolometer time constant and sensitivity. Our shunt resistors consist of AuPd strips grown atop of interdigitated superconducting MoN, wires. We can tailor the shunt resistance by altering the dimensions of the AuPd strips and the pitch and width of the MoN, wires and can fabricate over 1000 shunts on a single 4" wafer. By modeling the resistance dependence of these parameters, a variety of different 0.77 +I-0.13 mOhm shunt resistors have been fabricated. This variety includes different shunts possessing MoN, wires with wire width equal to 1.5 and 10 microns and pitch equal to 4.5 and 26 microns, respectively. Our ability to set the resistance of the shunts hints at the scalability of our design. We have also integrated a Si02 capping layer into our shunt resistor fabrication scheme, which inhibits metal corrosion and eventual degradation of the shunt. Consequently, their robustness coupled with their high packing density makes these resistive components attractive for future kilopixel detector arrays.

Mirror Illumination and Spillover Measurements of the Atacama Cosmology Telescope

NASA Technical Reports Server (NTRS)

Gallardo, Patricio; Dunner, Rolando; Wollack, Ed; Jerez-Hanckes, Carlos

2012-01-01

The Atacama Cosmology Telescope (ACT) is a 6 m telescope designed to map the Cosmic Microwave Background (CMB) simultaneously at 145 GHz, 220GHz and 280GHz, The receiver in ACT, the Millimeter Bolometer Array Camera, features 1000 TES bolometers in each band, The detector performance depends critically on the total optical loading, requiring the spmover contributions from the optics to be minimal. This inspired the use of a cold Lyot stop to limit the illumination of the primary and the use of guard rings surrounding the primary and secondary reflectors. Here, we present a direct measurement of the illumination aperture for both reflectors and of the attenuation level outside the main optical path. We used a 145 GHz, 1 m W source and a chopper wheel to produce a time-varying signal with a broad heam proflle, We sampled the response of the camera for different locations of the source, placed in front and beside the primary and secondary mirrors. The aperture of the primary was measured to be 5,72 plus or minus 0,17m in diameter (95 plus or minus 3% of its geometrical size), while the aperture of the secondary yielded 2 plus or minus 0.12m in diameter. Both apertures are consistent with the optical design. Comparing to previous measurements of the beam solid angle from planet observations, we estimate an optical efficiency of 72.3 plus or minus 4,8%. We found that the attenuation outside the primary aperture was -16 plus or minus 2dB, which is below the theoretical expectations, and -22 plus or minus 1 dB outside the secondary aperture, which is consistent with simulations. These results motivated the extension of the baffles surrounding the secondary mirror, with the following reduction in detector optical loading from 2,24 pW to 188pW.

Imaging antenna array at 119 microns. [for plasma diagnostics

NASA Technical Reports Server (NTRS)

Neikirk, N. P.; Tong, P. P.; Putledge, D. B.; Park, H.; Young, P. E.

1982-01-01

A focal-plane imaging antenna array has been demonstrated at 119 microns. The array is a line of evaporated silver bow-tie antennas with bismuth microbolometer detectors on a silicon substrate. Radiation is coupled into the array by a lens placed on the back of the substrate. The bolometers are thermally isolated from the silicon substrate with a half-micron layer of polyimide. The array performance is demonstrated by coherent imaging of a series of holes at half the diffraction-limited cut-off frequency.

Dual band sensitivity enhancements of a VO(x) microbolometer array using a patterned gold black absorber.

PubMed

Smith, Evan M; Panjwani, Deep; Ginn, James; Warren, Andrew P; Long, Christopher; Figuieredo, Pedro; Smith, Christian; Nath, Janardan; Perlstein, Joshua; Walter, Nick; Hirschmugl, Carol; Peale, Robert E; Shelton, David

2016-03-10

Infrared-absorbing gold black has been selectively patterned onto the active surfaces of a vanadium-oxide-based infrared bolometer array. Patterning by metal lift-off relies on protection of the fragile gold black with an evaporated oxide, which preserves much of gold black's high absorptance. This patterned gold black also survives the dry-etch removal of the sacrificial polyimide used to fabricate the air-bridge bolometers. For our fabricated devices, infrared responsivity is improved 22% in the long-wave IR and 70% in the mid-wave IR by the gold black coating, with no significant change in detector noise, using a 300°C blackbody and 80 Hz chopping rate. The increase in the time constant caused by the additional mass of gold black is ∼15%.

First array of enriched Zn$$^{82}$$Se bolometers to search for double beta decay

DOE PAGES

Artusa, D. R.; Balzoni, A.; Beeman, J. W.; ...

2016-07-01

The R&D activity performed during the last years proved the potential of ZnSe scintillating bolometers to the search for neutrino-less double beta decay, motivating the realization of the first large-mass experiment based on this technology: CUPID-0. The isotopic enrichment in 82Se, the Zn 82Se crystals growth, as well as the light detectors production have been accomplished, and the experiment is now in construction at Laboratori Nazionali del Gran Sasso (Italy). In this paper we present the results obtained testing the first three Zn 82Se crystals operated as scintillating bolometers, and we prove that their performance in terms of energy resolution,more » background rejection capability and intrinsic radio-purity complies with the requirements of CUPID-o.« less

Wire array K-shell sources on the SPHINX generator

NASA Astrophysics Data System (ADS)

D'Almeida, Thierry; Lassalle, Francis; Grunenwald, Julien; Maury, Patrick; Zucchini, Frédéric; Niasse, Nicolas; Chittenden, Jeremy

2014-10-01

The SPHINX machine is a LTD based Z-pinch driver operated by the CEA Gramat (France) and primarily used for studying K-shell radiation effects. We present the results of experiments carried out with single and nested large diameter aluminium wire array loads driven by a current of ~5 MA in ~800 ns. The dynamic of the implosion is studied with filtered X-UV time-integrated pin-hole cameras. The plasma electron temperature and the characteristics of the sources are estimated with time and spatially dependent spectrographs and PCDs. It is shown that Al K-shell yields (>1 keV) up to 27 kJ are obtained for a total radiation of ~ 230 kJ. These results are compared with simulations performed using the latest implementation of the non-LTE DCA code Spk in the 3D Eulerian MHD framework Gorgon developed at Imperial College. Filtered synthetic bolometers and PCD signals, time-dependent spatially integrated spectra and X-UV images are produced and show a good agreement with the experimental data. The capabilities of a prospective SPHINX II machine (20 MA ~ 800 ns) are also assessed for a wider variety of sources (Ti, Cu and W).

Fast Resistive Bolometry

NASA Astrophysics Data System (ADS)

Graham, Jeffrey

2005-10-01

A bolometer with microsecond scale response time is under construction for the Caltech spheromak experiment to measure radiation from a ˜20 μs duration plasma discharge emitting ˜10^2---10^3 kW/m^2. A gold film several micrometers thick absorbs the radiation, heats up, and the consequent change in resistance can be measured. The film itself is vacuum deposited upon a glass slide. Several geometries for the film are under consideration to optimize the amount of radiation absorbed, the response time and the signal-to-noise ratio. We measure the change in voltage across the film for a known current driven through it; a square pulse (3---30A, ˜20 μs) is used to avoid Joule heating. Results from prototypes tested with a UV flashlamp will be presented. After optimizing the bolometer design, the final vacuum-compatible diagnostic would consist of a plasma-facing bolometer and a reference in a camera obscura. This device could provide a design for fast resistive bolometry.

Carbon Nanotube Array for Infrared Detection

DTIC Science & Technology

2011-09-28

Scientific Progress Technology Transfer 1    Carbon Nanotube Array for Infrared Detection Final Report Jimmy Xu...devices. In contrast to photocarrier generation across a band gap, nature’s bolometers convert infrared radiation into heating of tissues thereby...been investigated. [5, 6] High TCR is, however, not the only important parameter for bolometric sensing. Heat capacity, thermal conductivity

Detailed in situ laser calibration of the infrared imaging video bolometer for the JT-60U tokamak

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

Parchamy, H.; Peterson, B. J.; Konoshima, S.

2006-10-15

The infrared imaging video bolometer (IRVB) in JT-60U includes a single graphite-coated gold foil with an effective area of 9x7 cm{sup 2} and a thickness of 2.5 {mu}m. The thermal images of the foil resulting from the plasma radiation are provided by an IR camera. The calibration technique of the IRVB gives confidence in the absolute levels of the measured values of the plasma radiation. The in situ calibration is carried out in order to obtain local foil properties such as the thermal diffusivity {kappa} and the product of the thermal conductivity k and the thickness t{sub f} of themore » foil. These quantities are necessary for solving the two-dimensional heat diffusion equation of the foil which is used in the experiments. These parameters are determined by comparing the measured temperature profiles (for kt{sub f}) and their decays (for {kappa}) with the corresponding results of a finite element model using the measured HeNe laser power profile as a known radiation power source. The infrared camera (Indigo/Omega) is calibrated by fitting the temperature rise of a heated plate to the resulting camera data using the Stefan-Boltzmann law.« less

Verification of the test stand for microbolometer camera in accredited laboratory

NASA Astrophysics Data System (ADS)

Krupiński, Michal; Bareła, Jaroslaw; Chmielewski, Krzysztof; Kastek, Mariusz

2017-10-01

Microbolometer belongs to the group of thermal detectors and consist of temperature sensitive resistor which is exposed to measured radiation flux. Bolometer array employs a pixel structure prepared in silicon technology. The detecting area is defined by a size of thin membrane, usually made of amorphous silicon (a-Si) or vanadium oxide (VOx). FPAs are made of a multitude of detector elements (for example 384 × 288 ), where each individual detector has different sensitivity and offset due to detector-to-detector spread in the FPA fabrication process, and additionally can change with sensor operating temperature, biasing voltage variation or temperature of the observed scene. The difference in sensitivity and offset among detectors (which is called non-uniformity) additionally with its high sensitivity, produces fixed pattern noise (FPN) on produced image. Fixed pattern noise degrades parameters of infrared cameras like sensitivity or NETD. Additionally it degrades image quality, radiometric accuracy and temperature resolution. In order to objectively compare the two infrared cameras ones must measure and compare their parameters on a laboratory test stand. One of the basic parameters for the evaluation of a designed camera is NETD. In order to examine the NETD, parameters such as sensitivity and pixels noise must be measured. To do so, ones should register the output signal from the camera in response to the radiation of black bodies at two different temperatures. The article presets an application and measuring stand for determining the parameters of microbolometers camera. Prepared measurements were compared with the result of the measurements in the Institute of Optoelectronics, MUT on a METS test stand by CI SYSTEM. This test stand consists of IR collimator, IR standard source, rotating wheel with test patterns, a computer with a video grabber card and specialized software. The parameters of thermals cameras were measure according to norms and method described in literature.

Phonon Recycling for Ultrasensitive Kinetic Inductance Detectors

NASA Astrophysics Data System (ADS)

Zmuidzinas, Jonas

Initially proposed (Day et al. 2003; Zmuidzinas 2012) in 1999 by our Caltech/JPL group, and thanks to strong support from NASA, the superconducting (microwave) kinetic inductance detector (MKID or KID) technology continues to develop rapidly as it transitions into applications. The development effort worldwide is intensifying and NASA's continued support of KID development is essential in order to keep pace. Here we propose to investigate and demonstrate a new, low-TRL concept, which we call phonon recycling, that promises to open broad new avenues in KID design and performance. Briefly, phonon recycling allows the detector designer to tailor the responsivity and sensitivity of a KID to match the needs of the application by using geometry to restrict the rate at which recombination phonons are allowed to escape from the detector. In particular, phonon recycling should allow very low noise-equivalent power (NEP) to be achieved without requiring very low operating tem- peratures. Phonon recycling is analogous to the use of micromachined suspension legs to control the flow of heat in a bolometer, as measured by the thermal conductivity G. However, phonon recycling exploits the non-thermal distribution of recombination phonons as well as their very slow decay in crystals at low temperatures. These properties translate to geometrical and mechanical requirements for a phonon-recycled KID that are considerably more relaxed than for a bolometer operating at the same temperature and NEP. Our ultimate goal is to develop detector arrays suitable for a far-infrared (FIR) space mission, which will impose strict requirements on the array sensitivity, yield, uniformity, multiplexing density, etc. Through previous NASA support under the Strategic Astrophysics Technology (SAT) program, we have successfully demonstrated the MAKO submillimeter camera at the Caltech Submillimeter Observatory and have become familiar with these practical issues. If our demonstration of phonon recycling is successful, we will have a path for continuously adapting the high-background, high-NEP detectors we have demonstrated on the ground to the ultralow-NEP detectors needed for space.

An FPGA-based bolometer for the MAST-U Super-X divertor.

PubMed

Lovell, Jack; Naylor, Graham; Field, Anthony; Drewelow, Peter; Sharples, Ray

2016-11-01

A new resistive bolometer system has been developed for MAST-Upgrade. It will measure radiated power in the new Super-X divertor, with millisecond time resolution, along 16 vertical and 16 horizontal lines of sight. The system uses a Xilinx Zynq-7000 series Field-Programmable Gate Array (FPGA) in the D-TACQ ACQ2106 carrier to perform real time data acquisition and signal processing. The FPGA enables AC-synchronous detection using high performance digital filtering to achieve a high signal-to-noise ratio and will be able to output processed data in real time with millisecond latency. The system has been installed on 8 previously unused channels of the JET vertical bolometer system. Initial results suggest good agreement with data from existing vertical channels but with higher bandwidth and signal-to-noise ratio.

The Atacama Cosmology Telescope: Development and preliminary results of point source observations

NASA Astrophysics Data System (ADS)

Fisher, Ryan P.

2009-06-01

The Atacama Cosmology Telescope (ACT) is a six meter diameter telescope designed to measure the millimeter sky with arcminute angular resolution. The instrument is currently conducting its third season of observations from Cerro Toco in the Chilean Andes. The primary science goal of the experiment is to expand our understanding of cosmology by mapping the temperature fluctuations of the Cosmic Microwave Background (CMB) at angular scales corresponding to multipoles up to [cursive l] ~ 10000. The primary receiver for current ACT observations is the Millimeter Bolometer Array Camera (MBAC). The instrument is specially designed to observe simultaneously at 148 GHz, 218 GHz and 277 GHz. To accomplish this, the camera has three separate detector arrays, each containing approximately 1000 detectors. After discussing the ACT experiment in detail, a discussion of the development and testing of the cold readout electronics for the MBAC is presented. Currently, the ACT collaboration is in the process of generating maps of the microwave sky using our first and second season observations. The analysis used to generate these maps requires careful data calibration to produce maps of the arcminute scale CMB temperature fluctuations. Tests and applications of several elements of the ACT calibrations are presented in the context of the second season observations. Scientific exploration has already begun on preliminary maps made using these calibrations. The final portion of this thesis is dedicated to discussing the point sources observed by the ACT. A discussion of the techniques used for point source detection and photometry is followed by a presentation of our current measurements of point source spectral indices.

VizieR Online Data Catalog: Selecting IRAC counterparts to SMGs (Alberts+, 2013)

NASA Astrophysics Data System (ADS)

Alberts, S.; Wilson, G. W.; Lu, Y.; Johnson, S.; Yun, M. S.; Scott, K. S.; Pope, A.; Aretxaga, I.; Ezawa, H.; Hughes, D. H.; Kawabe, R.; Kim, S.; Kohno, K.; Oshima, T.

2014-05-01

We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (~18"), this technique identifies ~85% of SMG counterparts. For much larger beam sizes (>~30"), we report identification rates of 33-49%. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope. (3 data files).

Implementation and performance of shutterless uncooled micro-bolometer cameras

NASA Astrophysics Data System (ADS)

Das, J.; de Gaspari, D.; Cornet, P.; Deroo, P.; Vermeiren, J.; Merken, P.

2015-06-01

A shutterless algorithm is implemented into the Xenics LWIR thermal cameras and modules. Based on a calibration set and a global temperature coefficient the optimal non-uniformity correction is calculated onboard of the camera. The limited resources in the camera require a compact algorithm, hence the efficiency of the coding is important. The performance of the shutterless algorithm is studied by a comparison of the residual non-uniformity (RNU) and signal-to-noise ratio (SNR) between the shutterless and shuttered correction algorithm. From this comparison we conclude that the shutterless correction is only slightly less performant compared to the standard shuttered algorithm, making this algorithm very interesting for thermal infrared applications where small weight and size, and continuous operation are important.

Cosmic evolution of star formation properties of galaxies

NASA Astrophysics Data System (ADS)

Kim, Sungeun

2014-01-01

Development of bolometer array and camera at submillimeter wavelength has played an important role in detecting submillimeter bright galaxies, so called submillimeter galaxies. These galaxies seem to be progenitors of present-day massive galaxies and account for their considerable contributions to the light from the early universe and their expected high star formation rates if there is a close link between the submillimeter galaxies and the star formation activities, and the interstellar dust in galaxies is mainly heated by the star light. We review assembly of submillimeter galaxies chosen from the AzTEC and the Herschel SPIRE/PACS data archives, and investigate their spectral energy distribution fits including the data at other wavelengths to deduce details about stellar parameters including star formation rates and parameters yielding the metallicity, composition and abundance in dust, and disc structure of these galaxies. This work has been supported in part by Mid-career Researcher Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology 2011-0028001.

Long-wave infrared profile feature extractor (PFx) sensor

NASA Astrophysics Data System (ADS)

Sartain, Ronald B.; Aliberti, Keith; Alexander, Troy; Chiu, David

2009-05-01

The Long Wave Infrared (LWIR) Profile Feature Extractor (PFx) sensor has evolved from the initial profiling sensor that was developed by the University of Memphis (Near IR) and the Army Research Laboratory (visible). This paper presents the initial signatures of the LWIR PFx for human with and without backpacks, human with animal (dog), and a number of other animals. The current version of the LWIR PFx sensor is a diverging optical tripwire sensor. The LWIR PFx signatures are compared to the signatures of the Profile Sensor in the visible and Near IR spectral regions. The LWIR PFx signatures were collected with two different un-cooled micro bolometer focal plane array cameras, where the individual pixels were used as stand alone detectors (a non imaging sensor). This approach results in a completely passive, much lower bandwidth, much longer battery life, low weight, small volume sensor that provides sufficient information to classify objects into human Vs non human categories with a 98.5% accuracy.

Measurements of the Optical Performance of Prototype TES Bolometers for SAFARI

NASA Astrophysics Data System (ADS)

Audley, M. D.; de Lange, G.; Ranjan, M.; Gao, J.-R.; Khosropanah, P.; Ridder, M. L.; Mauskopf, P. D.; Morozov, D.; Doherty, S.; Trappe, N.; Withington, S.

2014-09-01

We have measured the optical response of prototype detectors for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays, coupled with a Fourier transform spectrometer, will provide images of a 2'×2' field of view with spectral information over the wavelength range 34-210 μm. Each horn-coupled bolometer consists of a transition edge sensor (TES), with a transition temperature close to 100 mK, and a thin-film Ta absorber on a thermally-isolated silicon nitride membrane. SAFARI requires extremely sensitive detectors ( NEP˜2×10-19 W/), with correspondingly low saturation powers (˜5 fW), to take advantage of SPICA's cooled optics. To meet the challenge of testing such sensitive detectors we have constructed an ultra-low background test facility based on a cryogen-free high-capacity dilution refrigerator, paying careful attention to stray-light exclusion, shielding, and vibration isolation. For optical measurements the system contains internal cold (3-30 K) and hot (˜300 K) black-body calibration sources, as well as a light pipe for external illumination. We discuss our measurements of high optical efficiency in prototype SAFARI detectors and describe recent improvements to the test facility that will enable us to test the full SAFARI focal-plane arrays.

MgB2-Based Bolometer Array for Far Infra-Red Thermal Imaging and Fourier Transform Spectroscopy Applications

NASA Technical Reports Server (NTRS)

Lakew, B.; Aslam, S.; Brasunas, J.

2012-01-01

The mid-superconducting critical temperature (T(sub c) approximately 39 K) of the simple binary, intermetallic MgB, [1] makes it a very good candidate for the development of the next generation of electrooptical devices (e.g. [2]). In particular, recent advances in thin film deposition teclmiques to attain higb quality polycrystalline thin film MgB, deposited on SiN-Si substrates, with T(sub c) approximately 38K [3] coupled with the low voltage noise performance of the film [4] makes it higbly desirable for the development of moderately cooled bolometer arrays for integration into future space-bourne far infra-red (FIR) spectrometers and thermal mappers for studying the outer planets, their icy moons and other moons of interest in the 17-250 micrometer spectral wavelength range. Presently, commercially available pyroelectric detectors operating at 300 K have specific detectivity, D(*), around 7 x 10(exp 8) to 2 x 10(exp 9) centimeters square root of Hz/W. However, a MgB2 thin film based bolometer using a low-stress (less than 140 MPa) SiN membrane isolated from the substrate by a small thermal conductive link, operating at 38 K, promises to have two orders of magnitude higher specific detectivity [5][6].

Bolometeric detector arrays for CMB polarimetry

NASA Technical Reports Server (NTRS)

Kuo, C. L.; Bock, J. J.; Day, P.; Goldin, A.; Golwala, S.; Holmes, W.; Irwin, K.; Kenyon, M.; Lange, A. E.; LeDuc, H. G.;

The LUCIFER/CUPID-0 demonstrator: searching for the neutrinoless double-beta decay with Zn82Se scintillating bolometers

NASA Astrophysics Data System (ADS)

Artusa, D. R.; Balzoni, A.; Beeman, J. W.; Bellini, F.; Biassoni, M.; Brofferio, C.; Camacho, A.; Capelli, S.; Cardani, L.; Carniti, P.; Casali, N.; Cassina, L.; Clemenza, M.; Cremonesi, O.; Cruciani, A.; D'Addabbo, A.; Dafinei, I.; Di Domizio, S.; di Vacri, M. L.; Ferroni, F.; Gironi, L.; Giuliani, A.; Gotti, C.; Keppel, G.; Maino, M.; Mancuso, M.; Martinez, M.; Morganti, S.; Nagorny, S. S.; Nastasi, M.; Nisi, S.; Nones, C.; Orlandi, D.; Pagnanini, L.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Pirro, S.; Pozzi, S.; Previtali, E.; Puiu, A.; Rusconi, C.; Schäffner, K.; Tomei, C.; Vignati, M.; Zolotarova, A.

2017-09-01

Future experiments on neutrinoless double beta-decay with the aim of exploring the inverted hierarchy region have to employ detectors with excellent energy resolution and zero background in the energy region of interest. Cryogenic scintillating bolometers turn out to be a suitable candidate since they offer particle discrimination: the dual channel detection of the heat and the scintillation light signal allows for particle identification. In particular such detectors permit for a suppression of α-induced backgrounds, a key-issue for next-generation tonne-scale bolometric experiments. We report on the progress and current status of the LUCIFER/CUPID-0 demonstrator, the first array of scintillating bolometers based on enriched Zn82Se crystals which is expected to start data taking in 2016 and the potential of this detection technique for a future tonne-scale bolometric experiment after CUORE.

Thermal response of large area high temperature superconducting YBaCuO infrared bolometers

NASA Technical Reports Server (NTRS)

Khalil, Ali E.

1991-01-01

Thermal analysis of large area high temperature superconducting infrared detector operating in the equilibrium mode (bolometer) was performed. An expression for the temperature coefficient beta = 1/R(dR/dT) in terms of the thermal conductance and the thermal time constant of the detector were derived. A superconducting transition edge bolometer is a thermistor consisting of a thin film superconducting YBaCuO evaporated into a suitable thermally isolated substrate. The operating temperature of the bolometer is maintained close to the midpoint of the superconducting transition region where the resistance R has a maximum dynamic range. A detector with a strip configuration was analyzed and an expression for the temperature rise (delta T) above the ambient due to a uniform illumination with a source of power density was calculated. An expression for the thermal responsibility depends upon the spatial modulation frequency and the angular frequency of the incoming radiation. The problem of the thermal cross talk between different detector elements was addressed. In the case of monolithic HTS detector array with a row of square elements of dimensions 2a and CCD or CID readout electronics the thermal spread function was derived for different spacing between elements.

Developments in Time-Division Multiplexing of X-ray Transition-Edge Sensors

NASA Astrophysics Data System (ADS)

Doriese, W. B.; Morgan, K. M.; Bennett, D. A.; Denison, E. V.; Fitzgerald, C. P.; Fowler, J. W.; Gard, J. D.; Hays-Wehle, J. P.; Hilton, G. C.; Irwin, K. D.; Joe, Y. I.; Mates, J. A. B.; O'Neil, G. C.; Reintsema, C. D.; Robbins, N. O.; Schmidt, D. R.; Swetz, D. S.; Tatsuno, H.; Vale, L. R.; Ullom, J. N.

2016-07-01

Time-division multiplexing (TDM) is a mature scheme for the readout of arrays of transition-edge sensors (TESs). TDM is based on superconducting-quantum-interference-device (SQUID) current amplifiers. Multiple spectrometers based on gamma-ray and X-ray microcalorimeters have been operated with TDM readout, each at the scale of 200 sensors per spectrometer, as have several astronomical cameras with thousands of sub-mm or microwave bolometers. Here we present the details of two different versions of our TDM system designed to read out X-ray TESs. The first has been field-deployed in two 160-sensor (8 columns × 20 rows) spectrometers and four 240-sensor (8 columns × 30 rows) spectrometers. It has a three-SQUID-stage architecture, switches rows every 320 ns, and has total readout noise of 0.41 μ Φ 0 / surd Hz. The second, which is presently under development, has a two-SQUID-stage architecture, switches rows every 160 ns, and has total readout noise of 0.19 μ Φ 0 / surd Hz. Both quoted noise values are non-multiplexed and referred to the first-stage SQUID. In a demonstration of this new architecture, a multiplexed 1-column × 32-row array of NIST TESs achieved average energy resolution of 2.55± 0.01 eV at 6 keV.

Mechanical Design of a 4-Stage ADR for the PIPER mission

NASA Technical Reports Server (NTRS)

James, Bryan L.; Kimball, Mark O.; Shirron, Peter J.; Sampson, Michael A.; Letmate, Richard V.; Jackson, Michael L.

2017-01-01

The four 1,280 bolometer detector arrays that will fly on the balloon borne PIPER mission will be cooled by a 4-stage adiabatic demagnetization refrigerator (ADR). Two of the three mechanically independent ADR assemblies provide thermal isolation to their salt pills through Kevlar suspensions while the other provides thermal isolation to its salt pill through the use of bellows and Vespel material. The ADR integrates with the detector arrays and it sits in a large bucket Dewar containing superfluid liquid helium. This paper will describe the complex mechanical design of the PIPER ADR, and summarize the mechanical analysis done to validate the design.The four 1,280 bolometer detector arrays that will fly on the balloon borne PIPER mission will be cooled by a 4-stage adiabatic demagnetization refrigerator (ADR). Two of the three mechanically independent ADR assemblies provide thermal isolation to their salt pills through Kevlar suspensions while the other provides thermal isolation to its salt pill through the use of bellows and Vespel material. The ADR integrates with the detector arrays and it sits in a large bucket Dewar containing superfluid liquid helium. This paper will describe the complex mechanical design of the PIPER ADR, and summarize the mechanical analysis done to validate the design.

Submm/mm galaxy counterpart identification using a characteristic density distribution

NASA Astrophysics Data System (ADS)

Alberts, Stacey; Wilson, Grant W.; Lu, Yu; Johnson, Seth; Yun, Min S.; Scott, Kimberly S.; Pope, Alexandra; Aretxaga, Itziar; Ezawa, Hajime; Hughes, David H.; Kawabe, Ryohei; Kim, Sungeun; Kohno, Kotaro; Oshima, Tai

2013-05-01

We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (˜18 arcsec), this technique identifies ˜85 per cent of SMG counterparts. For much larger beam sizes (≳30 arcsec), we report identification rates of 33-49 per cent. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope.

The Green Bank Telescope: Transformational Science for the Next Decade.

NASA Astrophysics Data System (ADS)

Wootten, Al; GBO Staff

2018-01-01

The Robert C Byrd Green Bank Telescope has met its design goal of providing high-quality observations at 115 GHz. The accurate small beam of the telescope at high frequencies is leveraged by deployment of multi beam receivers. An overview is presented. Observers now have access to the new, 16-pixel, 3-mm Argus receiver, which is providing high-dynamic range images over wide fields for the multitude of spectral lines between 85 and 115 GHz. The successful performance of Argus, and its modular design, demonstrates that receivers with many more pixels could be built for the GBT. A 12 x 12 array of the Argus design would have mapping speeds about nine times faster than Argus without suffering any degradation in performance for the outer pixels in the array. The Observatory plans to build the next-generation Argus instrument (Argus+) with 144-pixels, a footprint 5'x5', and 7" resolution at 110 GHz. The project will be a collaboration between the Green Bank Observatory and university groups, who will supply key components. The key science drivers for Argus+ are studies of molecular filaments in the Milky Way, studies of molecular clouds in nearby galaxies, and the observations of rapidly evolving solar system objects. Observers also have access to MUSTANG-2, a 223-feedhorn bolometer camera which was commissioned on the GBT in spring 2016, and was offered for observations on a shared risk basis, in collaboration with the instrument team, in the 2018A GBO proposal call. Several features distinguish it from its predecessor, MUSTANG: A new, microstrip-coupled detector design yields higher sensitivity and less susceptibility to environmental microphonics. Detectors are feedhorn coupled, with the sum of two linear polarizations measured by a single TES per feed. The instantaneous field of view is 4 arcminutes (vs 42 arcseconds for MUSTANG) The receiver design incorporates a tilted refrigerator and receiver rotator, resulting in much lower dependence of cooling performance on telescope elevation. The detector readout is the first astronomical use of microwave resonators to multiplex TES bolometers. MUSTANG-2 has been developed by a collaboration including the University of Pennsylvania, NIST, NRAO, the University of Michigan, and Cardiff University. A 7-pixel K-band Feed Array covering 18-28 GHz with Dual polarization feeds and a noise temperature < 40-50 K has been available for several years. The array offers an instantaneous bandwidth/beam of 1.8 GHz. Future upgrade concepts under study envision increasing the number of beams by an order of magnitude.

ORAC-DR -- SCUBA Pipeline Data Reduction

NASA Astrophysics Data System (ADS)

Jenness, Tim; Economou, Frossie

ORAC-DR is a flexible data reduction pipeline designed to reduce data from many different instruments. This document describes how to use the ORAC-DR pipeline to reduce data taken with the Submillimetre Common-User Bolometer Array (SCUBA) obtained from the James Clerk Maxwell Telescope.

VizieR Online Data Catalog: Mass Distribution of Infrared Dark Clouds (Gomez+, 2014)

NASA Astrophysics Data System (ADS)

Gomez, L.; Wyrowski, F.; Shculler, F.; Menten, K. M.; Ballesteros-Paredes, J.

2014-01-01

Six southern hemisphere clouds with high extinction were observed on 2007-08-25/28 with the LABOCA (Large APEX BOlometer CAmera) instrument on the APEX 12m telescope, at a frequency of 345GHz and a bandwidth of 610GHz (for the instrument, see Siringo et al. 2009A&A...497..945S). (2 data files).

Optical performance of prototype horn-coupled TES bolometer arrays for SAFARI

NASA Astrophysics Data System (ADS)

Audley, Michael D.; de Lange, Gert; Gao, Jian-Rong; Khosropanah, Pourya; Hijmering, Richard; Ridder, Marcel L.

2016-07-01

The SAFARI Detector Test Facility is an ultra-low background optical testbed for characterizing ultra-sensitive prototype horn-coupled TES bolmeters for SAFARI, the grating spectrometer on board the proposed SPICA satellite. The testbed contains internal cold and hot black-body illuminators and a light-pipe for illumination with an external source. We have added reimaging optics to facilitate array optical measurements. The system is now being used for optical testing of prototype detector arrays read out with frequency-domain multiplexing. We present our latest optical measurements of prototype arrays and discuss these in terms of the instrument performance.

Imaging of breast cancer with mid- and long-wave infrared camera.

PubMed

Joro, R; Lääperi, A-L; Dastidar, P; Soimakallio, S; Kuukasjärvi, T; Toivonen, T; Saaristo, R; Järvenpää, R

2008-01-01

In this novel study the breasts of 15 women with palpable breast cancer were preoperatively imaged with three technically different infrared (IR) cameras - micro bolometer (MB), quantum well (QWIP) and photo voltaic (PV) - to compare their ability to differentiate breast cancer from normal tissue. The IR images were processed, the data for frequency analysis were collected from dynamic IR images by pixel-based analysis and from each image selectively windowed regional analysis was carried out, based on angiogenesis and nitric oxide production of cancer tissue causing vasomotor and cardiogenic frequency differences compared to normal tissue. Our results show that the GaAs QWIP camera and the InSb PV camera demonstrate the frequency difference between normal and cancerous breast tissue; the PV camera more clearly. With selected image processing operations more detailed frequency analyses could be applied to the suspicious area. The MB camera was not suitable for tissue differentiation, as the difference between noise and effective signal was unsatisfactory.

Study of Rare Nuclear Processes with CUORE

DOE PAGES

Alduino, C; Alfonso, K; III, FTA; ...

2018-03-30

TeO 2 bolometers have been used for many years to search for neutrinoless double beta decay in 130-Te. CUORE, a tonne-scale TeO 2 detector array, recently published the most sensitive limit on the half-life,more » $$T_{1/2}^{0\

Study of Rare Nuclear Processes with CUORE

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

Alduino, C; Alfonso, K; III, FTA

TeO 2 bolometers have been used for many years to search for neutrinoless double beta decay in 130-Te. CUORE, a tonne-scale TeO 2 detector array, recently published the most sensitive limit on the half-life,more » $$T_{1/2}^{0\

Commercialization of Micro-fabrication of Antenna-Coupled Transition Edge Sensor Bolometer Detectors for Studies of the Cosmic Microwave Background

NASA Astrophysics Data System (ADS)

Suzuki, Aritoki; Bebek, Chris; Garcia-Sciveres, Maurice; Holland, Stephen; Kusaka, Akito; Lee, Adrian T.; Palaio, Nicholas; Roe, Natalie; Steinmetz, Leo

2018-04-01

We report on the development of commercially fabricated multichroic antenna-coupled transition edge sensor (TES) bolometer arrays for cosmic microwave background (CMB) polarimetry experiments. CMB polarimetry experiments have deployed instruments in stages. Stage II experiments deployed with O(1000) detectors and reported successful detection of B-mode (divergence-free) polarization pattern in the CMB. Stage III experiments have recently started observing with O(10,000) detectors with wider frequency coverage. A concept for a stage IV experiment, CMB-S4, is emerging to make a definitive measurement of CMB polarization from the ground with O(400,000) detectors. The orders of magnitude increase in detector count for CMB-S4 require a new approach in detector fabrication to increase fabrication throughput and reduce the cost. We report on collaborative efforts with two commercial micro-fabrication foundries to fabricate antenna-coupled TES bolometer detectors. The detector design is based on the sinuous antenna-coupled dichroic detector from the POLARBEAR-2 experiment. The TES bolometers showed the expected I-V response, and the RF performance agrees with the simulation. We will discuss the motivation, design consideration, fabrication processes, test results, and how industrial detector fabrication could be a path to fabricate hundreds of detector wafers for future CMB polarimetry experiments.

The ArTéMiS wide-field sub-millimeter camera: preliminary on-sky performance at 350 microns

NASA Astrophysics Data System (ADS)

Revéret, Vincent; André, Philippe; Le Pennec, Jean; Talvard, Michel; Agnèse, Patrick; Arnaud, Agnès.; Clerc, Laurent; de Breuck, Carlos; Cigna, Jean-Charles; Delisle, Cyrille; Doumayrou, Eric; Duband, Lionel; Dubreuil, Didier; Dumaye, Luc; Ercolani, Eric; Gallais, Pascal; Groult, Elodie; Jourdan, Thierry; Leriche, Bernadette; Maffei, Bruno; Lortholary, Michel; Martignac, Jérôme; Rabaud, Wilfried; Relland, Johan; Rodriguez, Louis; Vandeneynde, Aurélie; Visticot, François

2014-07-01

ArTeMiS is a wide-field submillimeter camera operating at three wavelengths simultaneously (200, 350 and 450 μm). A preliminary version of the instrument equipped with the 350 μm focal plane, has been successfully installed and tested on APEX telescope in Chile during the 2013 and 2014 austral winters. This instrument is developed by CEA (Saclay and Grenoble, France), IAS (France) and University of Manchester (UK) in collaboration with ESO. We introduce the mechanical and optical design, as well as the cryogenics and electronics of the ArTéMiS camera. ArTeMiS detectors consist in Si:P:B bolometers arranged in 16×18 sub-arrays operating at 300 mK. These detectors are similar to the ones developed for the Herschel PACS photometer but they are adapted to the high optical load encountered at APEX site. Ultimately, ArTeMiS will contain 4 sub-arrays at 200 μm and 2×8 sub-arrays at 350 and 450 μm. We show preliminary lab measurements like the responsivity of the instrument to hot and cold loads illumination and NEP calculation. Details on the on-sky commissioning runs made in 2013 and 2014 at APEX are shown. We used planets (Mars, Saturn, Uranus) to determine the flat-field and to get the flux calibration. A pointing model was established in the first days of the runs. The average relative pointing accuracy is 3 arcsec. The beam at 350 μm has been estimated to be 8.5 arcsec, which is in good agreement with the beam of the 12 m APEX dish. Several observing modes have been tested, like "On- The-Fly" for beam-maps or large maps, spirals or raster of spirals for compact sources. With this preliminary version of ArTeMiS, we concluded that the mapping speed is already more than 5 times better than the previous 350 μm instrument at APEX. The median NEFD at 350 μm is 600 mJy.s1/2, with best values at 300 mJy.s1/2. The complete instrument with 5760 pixels and optimized settings will be installed during the first half of 2015.

The E and B EXperiment: Implementation and Analysis of the 2009 Engineering Flight

NASA Astrophysics Data System (ADS)

Milligan, Michael Bryce

The E and B EXperiment (EBEX) is a balloon-borne telescope designed to map the polarization of the cosmic microwave background (CMB) and emission from galactic dust at millimeter wavelengths from 150 to 410 GHz. The primary science objectives of EBEX are to: detect or constrain the primordial B-mode polarization of the CMB predicted by inflationary cosmology; measure the CMB B-mode signal induced by gravitational lensing; and characterize the polarized thermal emission from interstellar dust. EBEX will observe a 420 square degree patch of the sky at high galactic latitude with a telescope and camera that provide an 8 arcminute beam at three observing bands (150, 250, and 410 GHz) and a 6.2 degree diffraction limited field of view to two large-format bolometer array focal planes. Polarimetry is achieved via a continuously rotating half-wave plate (HWP), and the optical system is designed from the ground up for control of sidelobe response and polarization systematic errors. EBEX is intended to execute fly or more Antarctic long duration balloon campaigns. In June 2009 EBEX completed a North American engineering flight launched from NASA's Columbia Scientific Ballooning Facility (CSBF) in Ft. Sumner, NM and operated in the stratosphere above 30 km altitude for ˜10 hours. During flight EBEX must be largely autonomous as it conducts pointed, scheduled observations; tunes and operates 1432 TES bolometers via 28 embedded Digital frequency-domain multiplexing (DfMux) computers; logs over 3 GiB/hour of science and housekeeping data to onboard redundant disk storage arrays; manages and dispatches jobs over a fault-tolerant onboard Ethernet network; and feeds a complex real-time data processing infrastructure on the ground via satellite and line-of-sight (LOS) downlinks. In this thesis we review the EBEX instrument, present the optical design and the computational architecture for in-flight control and data handling, and the quick-look software stack. Finally we describe the 2009 North American test flight and present analysis of data collected at the end of that flight that characterizes scan-synchronous signals and the expected response to emission from thermal dust in our galaxy.

Highly Uniform 150 mm Diameter Multichroic Polarimeter Array Deployed for CMB Detection

NASA Technical Reports Server (NTRS)

Ho, Shuay-Pwu Patty; Austermann, Jason; Beall, James A.; Choi, Steve K.; Cothard, Nicholas F.; Crowley, Kevin; Datta, Rahul; Devlin, Mark J.; Duff, Shannon M.; Wollack, Edward J.

2016-01-01

The Advanced Atacama Cosmology Telescope Polarimeter is an upgraded receiver for the Atacama Cosmology Telescope, which has begun making measurements of the small angular scale polarization anisotropies in the Cosmic Microwave Background using the first of four new multichroic superconducting detector arrays. Here, we review all details of the optimization and characterization of this first array, which features 2012 AlMn transition edge sensor bolometers operating at 150 and 230 GHz. We present critical temperatures, thermal conductivities,saturation powers, time constants, and sensitivities for the array. The results show high uniformity across the 150 mm wafer and good performance in the field.

Thermopile Detector Arrays for Space Science Applications

NASA Technical Reports Server (NTRS)

Foote, M. C.; Kenyon, M.; Krueger, T. R.; McCann, T. A.; Chacon, R.; Jones, E. W.; Dickie, M. R.; Schofield, J. T.; McCleese, D. J.; Gaalema, S.

2004-01-01

Thermopile detectors are widely used in uncooled applications where small numbers of detectors are required, particularly in low-cost commercial applications or applications requiring accurate radiometry. Arrays of thermopile detectors, however, have not been developed to the extent of uncooled bolometer and pyroelectric/ferroelectric arrays. Efforts at JPL seek to remedy this deficiency by developing high performance thin-film thermopile detectors in both linear and two-dimensional formats. The linear thermopile arrays are produced by bulk micromachining and wire bonded to separate CMOS readout electronic chips. Such arrays are currently being fabricated for the Mars Climate Sounder instrument, scheduled for launch in 2005. Progress is also described towards realizing a two-dimensional thermopile array built over CMOS readout circuitry in the substrate.

Large mass bolometers for neutrinoless double beta decay detection: model and last results

NASA Astrophysics Data System (ADS)

Pedretti, Marisa; Barucci, Marco; Giuliani, Andrea; Pasca, Edoardo; Risegari, Lara; Olivieri, Emiliano; Ventura, Guglielmo

2004-01-01

Milano collaboration has been developing for many years large mass bolometers for particle detection, and in particular for the study of neutrinoless double beta decay of 130Te. The active components of the detectors are large mass (340 g and 790 g) TeO2 crystals, while Neutron Transmutation Doped Ge thermistors are used as phonon sensors. These devices work at low temperatures, about 5-10 mK. The mechanical and thermal connections of the detector to the thermal bath are made with PTFE pieces that hold the crystal on copper frames. Gold wires are used as electric connections. We have developed a complete thermal model for the bolometers and "ad hoc" measurements of the thermal parameters involved were performed in the Florence cryogenic laboratory. These studies have permitted to simulate the static and dynamic behaviours of the detectors. A satisfactory agreement between simulated and the experimental response has been obtained as far as the static behaviour is concerned, while the dynamic behaviour is not yet fully understood. These preliminary results however will enable us to design new detector structures in order to improve the signal-to-noise ratio and the reproducibility. Given the good performances of these devices (excellent energy resolutions were obtained, of the order of 2 keV at 911 keV and of 5 keV at 2615 keV), this technique is particularly suitable to detectors for gamma ray spectroscopy. Encouraged by this results, the Milano-Como group has joined a large international collaboration for the realization of CUORE (Cryogenic Underground Observatory for Rare Events), seraching for Dark Matter and neutrinoless Double Beta Decay, a crucial phenomenon for neutrino physics. The Cuoricino detector, a small scale test of CUORE detector, is an array of 62 large mass bolometers like those already described, and it is now in operation in the Gran Sasso undergrand laboratory, Italy). It is the largest array of bolometric detectors ever constructed.

Preliminary design of a tangentially viewing imaging bolometer for NSTX-U

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

Peterson, B. J., E-mail: peterson@LHD.nifs.ac.jp; Mukai, K.; SOKENDAI

2016-11-15

The infrared imaging video bolometer (IRVB) measures plasma radiated power images using a thin metal foil. Two different designs with a tangential view of NSTX-U are made assuming a 640 × 480 (1280 × 1024) pixel, 30 (105) fps, 50 (20) mK, IR camera imaging the 9 cm × 9 cm × 2 μm Pt foil. The foil is divided into 40 × 40 (64 × 64) IRVB channels. This gives a spatial resolution of 3.4 (2.2) cm on the machine mid-plane. The noise equivalent power density of the IRVB is given as 113 (46) μW/cm{sup 2} for a timemore » resolution of 33 (20) ms. Synthetic images derived from Scrape Off Layer Plasma Simulation data using the IRVB geometry show peak signal levels ranging from ∼0.8 to ∼80 (∼0.36 to ∼26) mW/cm{sup 2}.« less

Preliminary design of a tangentially viewing imaging bolometer for NSTX-U

DOE PAGES

Peterson, B. J.; Sano, R.; Reinke, M. L.; ...

2016-08-03

The InfraRed imaging Video Bolometer measures plasma radiated power images using a thin metal foil. Two different designs with a tangential view of NSTX-U are made assuming a 640 x 480 (1280 x 1024) pixel, 30 (105) fps, 50 (20) mK, IR camera imaging the 9 cm x 9 cm x 2 μm Pt foil. The foil is divided into 40 x 40 (64 x 64) IRVB channels. This gives a spatial resolution of 3.4 (2.2) cm on the machine mid-plane. The noise equivalent power density of the IRVB is given as 113 (46) μW/cm 2 for a time resolutionmore » of 33 (20) ms. Synthetic images derived from SOLPS data using the IRVB geometry show peak signal levels ranging from ~0.8 - ~80 (~0.36 - ~26) mW/cm 2.« less

Bolometer Results in the Long-Microwave-Heated WEGA Stellarator

NASA Astrophysics Data System (ADS)

Zhang, D.; Otte, M.; Giannone, L.

2006-01-01

A 12 channel bolometer camera based on a gold foil absorber has been installed on the WEGA stellarator to measure the radiation power losses of the plasma. The measured total radiation power is typically less than 30% of the ECRH input power. However, this radiated power fraction depends on the ECRH input power, the magnetic configuration and the field strength as well as the working gas. For separatrix-bounded configurations, core-peaked radiation intensity profiles are usually detected, while in a limiter-configuration they are flatter, broader and more asymmetric. In addition, significant radiation originating from the SOL region is measured for all the cases studied. The SOL radiation changes with changing the plasma-wave interaction region, indicating a strong correlation between radiation and power deposition. Under the WEGA-plasma conditions (Te<10 eV), it is considered that the radiation profile reflects the plasma pressure associated with the power deposition distribution of the ECRH.

Noninvasive Spatially Offset and Transmission Raman Mapping of Breast Tissue: A Multimodal Approach Towards the In Vivo assessment of Tissue Pathology

DTIC Science & Technology

2013-04-01

liquid nitrogen cooled mercury cadmium telluride ( MCT ) detector and compare their performance to a commercial FT-IR imaging instrument. We examine the...telluride ( MCT ) detector (InfraRed Associates, Stuart, FL), and in a second widefield imaging configuration, we employed a cooled focal plane array (FPA...experiment, a cooled focal plane array (FPA) was substituted for the bolometer. (b) A cooled single-element MCT detector is utilized with an adjustable

Silicon-based antenna-coupled polarization-sensitive millimeter-wave bolometer arrays for cosmic microwave background instruments

NASA Astrophysics Data System (ADS)

Rostem, Karwan; Ali, Aamir; Appel, John W.; Bennett, Charles L.; Brown, Ari; Chang, Meng-Ping; Chuss, David T.; Colazo, Felipe A.; Costen, Nick; Denis, Kevin L.; Essinger-Hileman, Tom; Hu, Ron; Marriage, Tobias A.; Moseley, Samuel H.; Stevenson, Thomas R.; U-Yen, Kongpop; Wollack, Edward J.; Xu, Zhilei

2016-07-01

We describe feedhorn-coupled polarization-sensitive detector arrays that utilize monocrystalline silicon as the dielectric substrate material. Monocrystalline silicon has a low-loss tangent and repeatable dielectric constant, characteristics that are critical for realizing efficient and uniform superconducting microwave circuits. An additional advantage of this material is its low specific heat. In a detector pixel, two Transition-Edge Sensor (TES) bolometers are antenna-coupled to in-band radiation via a symmetric planar orthomode transducer (OMT). Each orthogonal linear polarization is coupled to a separate superconducting microstrip transmission line circuit. On-chip filtering is employed to both reject out-of-band radiation from the upper band edge to the gap frequency of the niobium superconductor, and to flexibly define the bandwidth for each TES to meet the requirements of the application. The microwave circuit is compatible with multi-chroic operation. Metalized silicon platelets are used to define the backshort for the waveguide probes. This micro-machined structure is also used to mitigate the coupling of out-of-band radiation to the microwave circuit. At 40 GHz, the detectors have a measured efficiency of ˜90%. In this paper, we describe the development of the 90 GHz detector arrays that will be demonstrated using the Cosmology Large Angular Scale Surveyor (CLASS) ground-based telescope.

Hafnium Films and Magnetic Shielding for TIME, A mm-Wavelength Spectrometer Array

NASA Astrophysics Data System (ADS)

Hunacek, J.; Bock, J.; Bradford, C. M.; Butler, V.; Chang, T.-C.; Cheng, Y.-T.; Cooray, A.; Crites, A.; Frez, C.; Hailey-Dunsheath, S.; Hoscheit, B.; Kim, D. W.; Li, C.-T.; Marrone, D.; Moncelsi, L.; Shirokoff, E.; Steinbach, B.; Sun, G.; Trumper, I.; Turner, A.; Uzgil, B.; Weber, A.; Zemcov, M.

2018-04-01

TIME is a mm-wavelength grating spectrometer array that will map fluctuations of the 157.7-μm emission line of singly ionized carbon ([CII]) during the epoch of reionization (redshift z ˜ 5-9). Sixty transition-edge sensor (TES) bolometers populate the output arc of each of the 32 spectrometers, for a total of 1920 detectors. Each bolometer consists of gold absorber on a ˜ 3 × 3 mm silicon nitride micro-mesh suspended near the corners by 1 × 1 × 500 μm silicon nitride legs targeting a photon-noise-dominated NEP ˜ 1 × 10^{-17} W/√{Hz} . Hafnium films are explored as a lower-T_c alternative to Ti (500 mK) for TIME TESs, allowing thicker support legs for improved yield. Hf T_c is shown to vary between 250 and 450 mK when varying the resident Ar pressure during deposition. Magnetic shielding designs and simulations are presented for the TIME first-stage SQUIDs. Total axial field suppression is predicted to be 5 × 10^7.

Complete event-by-event α /γ (β ) separation in a full-size TeO2 CUORE bolometer by Neganov-Luke-magnified light detection

NASA Astrophysics Data System (ADS)

Bergé, L.; Chapellier, M.; de Combarieu, M.; Dumoulin, L.; Giuliani, A.; Gros, M.; de Marcillac, P.; Marnieros, S.; Nones, C.; Novati, V.; Olivieri, E.; Paul, B.; Poda, D. V.; Redon, T.; Siebenborn, B.; Zolotarova, A. S.; Armengaud, E.; Augier, C.; Benoît, A.; Billard, J.; Broniatowski, A.; Camus, P.; Cazes, A.; Charlieux, F.; De Jesus, M.; Eitel, K.; Foerster, N.; Gascon, J.; Jin, Y.; Juillard, A.; Kleifges, M.; Kozlov, V.; Kraus, H.; Kudryavtsev, V. A.; Le Sueur, H.; Maisonobe, R.; Navick, X.-F.; Pari, P.; Queguiner, E.; Rozov, S.; Sanglard, V.; Vagneron, L.; Weber, M.; Yakushev, E.

2018-03-01

In the present work, we describe the results obtained with a large (≈133 cm3 ) TeO2 bolometer, with a view to a search for neutrinoless double-β decay (0 ν β β ) of 130Te. We demonstrate an efficient α -particle discrimination (99.9%) with a high acceptance of the 0 ν β β signal (about 96%), expected at ≈2.5 MeV. This unprecedented result was possible thanks to the superior performance (10-eV rms baseline noise) of a Neganov-Luke-assisted germanium bolometer used to detect a tiny (70-eV) light signal from the TeO2 detector, dominated by γ (β )-induced Cherenkov radiation but exhibiting also a clear scintillation component. The obtained results represent a major breakthrough toward the TeO2-based version of the CUORE Upgrade with Particle IDentification (CUPID), a ton-scale cryogenic 0 ν β β experiment proposed as a followup to the Cryogenic Underground Observatory for Rare Events (CUORE) project with particle identification. The CUORE experiment recently began a search for neutrinoless double-β decay of 130Te with an array of 988 125-cm3TeO2 bolometers. The lack of α discrimination in CUORE makes α decays at the detector surface the dominant background component, at the level of ≈0.01 counts/(keV kg y) in the region of interest. We show here, for the first time with a CUORE-size bolometer and using the same technology as CUORE for the readout of both heat and light signals, that surface α background can be fully rejected.

Cryogenic bolometric systems

NASA Astrophysics Data System (ADS)

Kangas, Miikka Matias

The big bang, early galaxy formation, the interstellar medium, and high z galaxy cluster evolution are all science objectives that are studied in the far infrared (FIR). The cosmological parameters that describe the universe are encoded in anisotropies in the Cosmic Microwave Background (CMB), and can be extracted from precision subdegree angular resolution FIR maps. Cryogenic bolometers are well suited for these science objectives, and are evolving rapidly today. A cryogenic bolometric system is made up of a few building blocks, which can be modularized or integrated depending on the maturity of the scientific field they are used for. Integration of systems increases with the maturity of the technology. The basic building blocks are the bolometer, the cryogenics, the dewar, the optics, the filters, and electronics. The electronics can be further subdivided into room temperature back-end and cryogenic front-end electronics. The electronics are often partly integrated into the dewar. The dewar is part of the support structure, and only the subkelvin portion the dewar is referred to as cryogenics here. Each of these can be a sophisticated engineering feat on their own, and this dissertation revolves around the development of several of these elements. The microfabrication sequence for a free standing micromesh detector was developed. Polarization preserving photometer optics and filters were constructed and tested. A test dewar mechanical and optical structure was created to test single pixel photometers prior to mounting in the flight dewar. A modular flight dewar capable of holding an array of photometers and adaptable to a number of different cryogenics schemes and detector arrays was engineered and constructed. A zero gravity dilution refrigerator coil was constructed and tested. A corrugated platelet array concept was designed and tested. Metal mesh filter design and fabrication techniques were developed. Kevlar isolator structures were improved to work in subkelvin dewars, and detector modules that mounted the bolometer chips to the photometer tubes were created. These subsystems underwent testing to compare the predicted behavior and actual performance.

Diagnosing x-ray power and energy of tungsten wire array z-pinch with a flat spectral response x-ray diode

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

Wang, Kun-lun; Ren, Xiao-dong; Huang, Xian-bin, E-mail: caephxb2003@aliyun.com

2015-11-15

Fast z-pinch is a very efficient way of converting electromagnetic energy to radiation. With an 8-10 MA current on primary test stand facility, about 1 MJ electromagnetic energy is delivered to vacuum chamber, which heats z-pinch plasma to radiate soft x-ray. To develop a pulsed high power x-ray source, we studied the applicability of diagnosing x-ray power from tungsten wire array z-pinch with a flat spectral response x-ray diode (FSR-XRD). The detector was originally developed to diagnose radiation of a hohlraum in SG-III prototype laser facility. It utilized a gold cathode XRD and a specially configured compound gold filter tomore » yield a nearly flat spectral response in photon energy range of 0.1-4 keV. In practice, it was critical to avoid surface contamination of gold cathode. It is illustrated that an exposure of an XRD to multiple shots caused a significant change of response. Thus, in diagnosing x-ray power and energy, we used each XRD in only one shot after calibration. In a shot serial, output of FSR-XRD was compared with output of a nickel bolometer. In these shots, the outputs agreed with each other within their uncertainties which were about 12% for FSR-XRD and about 15% for bolometer. Moreover, the ratios between the FSR-XRD and the bolometer among different shots were explored. In 8 shots, the standard deviation of the ratio was 6%. It is comparable to XRD response change of 7%.« less

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

Lovell, Jack, E-mail: jack.lovell@durham.ac.uk; Culham Centre for Fusion Energy, Culham Science Centre, Abingdon, Oxon OX14 3DB; Naylor, Graham

A new resistive bolometer system has been developed for MAST-Upgrade. It will measure radiated power in the new Super-X divertor, with millisecond time resolution, along 16 vertical and 16 horizontal lines of sight. The system uses a Xilinx Zynq-7000 series Field-Programmable Gate Array (FPGA) in the D-TACQ ACQ2106 carrier to perform real time data acquisition and signal processing. The FPGA enables AC-synchronous detection using high performance digital filtering to achieve a high signal-to-noise ratio and will be able to output processed data in real time with millisecond latency. The system has been installed on 8 previously unused channels of themore » JET vertical bolometer system. Initial results suggest good agreement with data from existing vertical channels but with higher bandwidth and signal-to-noise ratio.« less

Fabrication of Low-Noise TES Arrays for the SAFARI Instrument on SPICA

NASA Astrophysics Data System (ADS)

Ridder, M. L.; Khosropanah, P.; Hijmering, R. A.; Suzuki, T.; Bruijn, M. P.; Hoevers, H. F. C.; Gao, J. R.; Zuiddam, M. R.

2016-07-01

Ultra-low-noise transition edge sensors (TES) with noise equivalent power lower than 2 × 10^{-19} W/Hz^{1/2 } have been fabricated by SRON, which meet the sensitivity requirements for the far-infrared SAFARI instrument on space infrared telescope for cosmology and astrophysics. Our TES detector is based on a titanium/gold (Ti/Au) thermistor on a silicon nitride (SiN) island. The island is thermally linked with SiN legs to a silicon support structure at the bath temperature. The SiN legs are very thin (250 nm), narrow (500 nm), and long (above 300 {\\upmu } m); these dimensions are needed in leg-isolated bolometers to achieve the required level of sensitivity. In this paper, we describe the latest fabrication process for our TES bolometers with improved sensitivity.

Carbon Nanotube Bolometer for Absolute FTIR Spectroscopy

NASA Astrophysics Data System (ADS)

Woods, Solomon; Neira, Jorge; Tomlin, Nathan; Lehman, John

We have developed and calibrated planar electrical-substitution bolometers which employ absorbers made from vertically-aligned carbon nanotube arrays. The nearly complete absorption of light by the carbon nanotubes from the visible range to the far-infrared can be exploited to enable a device with read-out in native units equivalent to optical power. Operated at cryogenic temperatures near 4 K, these infrared detectors are designed to have time constant near 10 ms and a noise floor of about 10 pW. Built upon a micro-machined silicon platform, each device has an integrated heater and thermometer, either a carbon nanotube thermistor or superconducting transition edge sensor, for temperature control. We are optimizing temperature-controlled measurement techniques to enable high resolution spectral calibrations using these devices with a Fourier-transform spectrometer.

The LABOCA/ACT Survey of Clusters at All Redshifts: Multiwavelength Analysis of Background Submillimeter Galaxies

NASA Astrophysics Data System (ADS)

Aguirre, Paula; Lindner, Robert R.; Baker, Andrew J.; Bond, J. Richard; Dünner, Rolando; Galaz, Gaspar; Gallardo, Patricio; Hilton, Matt; Hughes, John P.; Infante, Leopoldo; Lima, Marcos; Menten, Karl M.; Sievers, Jonathan; Weiss, Axel; Wollack, Edward J.

2018-03-01

We present a multiwavelength analysis of 48 submillimeter galaxies (SMGs) detected in the Large APEX Bolometer Camera/Atacama Cosmology Telescope (ACT) Survey of Clusters at All Redshifts, LASCAR, which acquired new 870 μm and Australia Telescope Compact Array 2.1 GHz observations of 10 galaxy clusters detected through their Sunyaev–Zel’dovich effect (SZE) signal by the ACT. Far-infrared observations were also conducted with the Photodetector Array Camera and Spectrometer (100/160 μm) and SPIRE (250/350/500 μm) instruments on Herschel for sample subsets of five and six clusters. LASCAR 870 μm maps were reduced using a multiscale iterative pipeline that removes the SZE increment signal, yielding point-source sensitivities of σ ∼ 2 mJy beam‑1. We detect in total 49 sources at the 4σ level and conduct a detailed multiwavelength analysis considering our new radio and far-IR observations plus existing near-IR and optical data. One source is identified as a foreground galaxy, 28 SMGs are matched to single radio sources, four have double radio counterparts, and 16 are undetected at 2.1 GHz but tentatively associated in some cases to near-IR/optical sources. We estimate photometric redshifts for 34 sources with secure (25) and tentative (9) matches at different wavelengths, obtaining a median z={2.8}-1.7+2.1. Compared to previous results for single-dish surveys, our redshift distribution has a comparatively larger fraction of sources at z > 3, and the high-redshift tail is more extended. This is consistent with millimeter spectroscopic confirmation of a growing number of high-z SMGs and relevant for testing of cosmological models. Analytical lens modeling is applied to estimate magnification factors for 42 SMGs at clustercentric radii >1.‧2 with the demagnified flux densities and source-plane areas, we obtain integral number counts that agree with previous submillimeter surveys.

VizieR Online Data Catalog: Galactic CHaMP. II. Dense gas clumps. (Ma+, 2013)

NASA Astrophysics Data System (ADS)

Ma, B.; Tan, J. C.; Barnes, P. J.

2015-04-01

A total of 303 dense gas clumps have been detected using the HCO+(1-0) line in the CHaMP survey (Paper I, Barnes et al. 2011, J/ApJS/196/12). In this article we have derived the SED for these clumps using Spitzer, MSX, and IRAS data. The Midcourse Space Experiment (MSX) was launched in 1996 April. It conducted a Galactic plane survey (0

BAE Systems' 17μm LWIR camera core for civil, commercial, and military applications

NASA Astrophysics Data System (ADS)

Lee, Jeffrey; Rodriguez, Christian; Blackwell, Richard

2013-06-01

Seventeen (17) µm pixel Long Wave Infrared (LWIR) Sensors based on vanadium oxide (VOx) micro-bolometers have been in full rate production at BAE Systems' Night Vision Sensors facility in Lexington, MA for the past five years.[1] We introduce here a commercial camera core product, the Airia-MTM imaging module, in a VGA format that reads out in 30 and 60Hz progressive modes. The camera core is architected to conserve power with all digital interfaces from the readout integrated circuit through video output. The architecture enables a variety of input/output interfaces including Camera Link, USB 2.0, micro-display drivers and optional RS-170 analog output supporting legacy systems. The modular board architecture of the electronics facilitates hardware upgrades allow us to capitalize on the latest high performance low power electronics developed for the mobile phones. Software and firmware is field upgradeable through a USB 2.0 port. The USB port also gives users access to up to 100 digitally stored (lossless) images.

First Observations of the Magnetic Field inside the Pillars of Creation: Results from the BISTRO Survey

NASA Astrophysics Data System (ADS)

Pattle, Kate; Ward-Thompson, Derek; Hasegawa, Tetsuo; Bastien, Pierre; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Furuya, Ray; Berry, David; JCMT BISTRO Survey Team

2018-06-01

We present the first high-resolution, submillimeter-wavelength polarimetric observations of—and thus direct observations of the magnetic field morphology within—the dense gas of the Pillars of Creation in M16. These 850 μm observations, taken as part of the B-Fields in Star-forming Region Observations Survey (BISTRO) using the POL-2 polarimeter on the Submillimeter Common-User Bolometer Array 2 (SCUBA-2) camera on the James Clerk Maxwell Telescope (JCMT), show that the magnetic field runs along the length of the Pillars, perpendicular to and decoupled from the field in the surrounding photoionized cloud. Using the Chandrasekhar–Fermi method we estimate a plane-of-sky magnetic field strength of 170–320 μG in the Pillars, consistent with their having been formed through the compression of gas with initially weak magnetization. The observed magnetic field strength and morphology suggests that the magnetic field may be slowing the Pillars’ evolution into cometary globules. We thus hypothesize that the evolution and lifetime of the Pillars may be strongly influenced by the strength of the coupling of their magnetic field to that of their parent photoionized cloud—i.e., that the Pillars’ longevity results from magnetic support.

The LiteBIRD Satellite Mission: Sub-Kelvin Instrument

NASA Astrophysics Data System (ADS)

Suzuki, A.; Ade, P. A. R.; Akiba, Y.; Alonso, D.; Arnold, K.; Aumont, J.; Baccigalupi, C.; Barron, D.; Basak, S.; Beckman, S.; Borrill, J.; Boulanger, F.; Bucher, M.; Calabrese, E.; Chinone, Y.; Cho, S.; Crill, B.; Cukierman, A.; Curtis, D. W.; de Haan, T.; Dobbs, M.; Dominjon, A.; Dotani, T.; Duband, L.; Ducout, A.; Dunkley, J.; Duval, J. M.; Elleflot, T.; Eriksen, H. K.; Errard, J.; Fischer, J.; Fujino, T.; Funaki, T.; Fuskeland, U.; Ganga, K.; Goeckner-Wald, N.; Grain, J.; Halverson, N. W.; Hamada, T.; Hasebe, T.; Hasegawa, M.; Hattori, K.; Hattori, M.; Hayes, L.; Hazumi, M.; Hidehira, N.; Hill, C. A.; Hilton, G.; Hubmayr, J.; Ichiki, K.; Iida, T.; Imada, H.; Inoue, M.; Inoue, Y.; Irwin, K. D.; Ishino, H.; Jeong, O.; Kanai, H.; Kaneko, D.; Kashima, S.; Katayama, N.; Kawasaki, T.; Kernasovskiy, S. A.; Keskitalo, R.; Kibayashi, A.; Kida, Y.; Kimura, K.; Kisner, T.; Kohri, K.; Komatsu, E.; Komatsu, K.; Kuo, C. L.; Kurinsky, N. A.; Kusaka, A.; Lazarian, A.; Lee, A. T.; Li, D.; Linder, E.; Maffei, B.; Mangilli, A.; Maki, M.; Matsumura, T.; Matsuura, S.; Meilhan, D.; Mima, S.; Minami, Y.; Mitsuda, K.; Montier, L.; Nagai, M.; Nagasaki, T.; Nagata, R.; Nakajima, M.; Nakamura, S.; Namikawa, T.; Naruse, M.; Nishino, H.; Nitta, T.; Noguchi, T.; Ogawa, H.; Oguri, S.; Okada, N.; Okamoto, A.; Okamura, T.; Otani, C.; Patanchon, G.; Pisano, G.; Rebeiz, G.; Remazeilles, M.; Richards, P. L.; Sakai, S.; Sakurai, Y.; Sato, Y.; Sato, N.; Sawada, M.; Segawa, Y.; Sekimoto, Y.; Seljak, U.; Sherwin, B. D.; Shimizu, T.; Shinozaki, K.; Stompor, R.; Sugai, H.; Sugita, H.; Suzuki, J.; Tajima, O.; Takada, S.; Takaku, R.; Takakura, S.; Takatori, S.; Tanabe, D.; Taylor, E.; Thompson, K. L.; Thorne, B.; Tomaru, T.; Tomida, T.; Tomita, N.; Tristram, M.; Tucker, C.; Turin, P.; Tsujimoto, M.; Uozumi, S.; Utsunomiya, S.; Uzawa, Y.; Vansyngel, F.; Wehus, I. K.; Westbrook, B.; Willer, M.; Whitehorn, N.; Yamada, Y.; Yamamoto, R.; Yamasaki, N.; Yamashita, T.; Yoshida, M.

2018-05-01

Inflation is the leading theory of the first instant of the universe. Inflation, which postulates that the universe underwent a period of rapid expansion an instant after its birth, provides convincing explanation for cosmological observations. Recent advancements in detector technology have opened opportunities to explore primordial gravitational waves generated by the inflation through "B-mode" (divergent-free) polarization pattern embedded in the cosmic microwave background anisotropies. If detected, these signals would provide strong evidence for inflation, point to the correct model for inflation, and open a window to physics at ultra-high energies. LiteBIRD is a satellite mission with a goal of detecting degree-and-larger-angular-scale B-mode polarization. LiteBIRD will observe at the second Lagrange point with a 400 mm diameter telescope and 2622 detectors. It will survey the entire sky with 15 frequency bands from 40 to 400 GHz to measure and subtract foregrounds. The US LiteBIRD team is proposing to deliver sub-Kelvin instruments that include detectors and readout electronics. A lenslet-coupled sinuous antenna array will cover low-frequency bands (40-235 GHz) with four frequency arrangements of trichroic pixels. An orthomode-transducer-coupled corrugated horn array will cover high-frequency bands (280-402 GHz) with three types of single frequency detectors. The detectors will be made with transition edge sensor (TES) bolometers cooled to a 100 milli-Kelvin base temperature by an adiabatic demagnetization refrigerator. The TES bolometers will be read out using digital frequency multiplexing with Superconducting QUantum Interference Device (SQUID) amplifiers. Up to 78 bolometers will be multiplexed with a single SQUID amplifier. We report on the sub-Kelvin instrument design and ongoing developments for the LiteBIRD mission.

A Dry-Etch Process for Low Temperature Superconducting Transition Edge Sensors for Far Infrared Bolometer Arrays

NASA Technical Reports Server (NTRS)

Allen, Christine A.; Chervenak, James A.; Hsieh, Wen-Ting; McClanahan, Richard A.; Miller, Timothy M.; Mitchell, Robert; Moseley, S. Harvey; Staguhn, Johannes; Stevenson, Thomas R.

2003-01-01

The next generation of ultra-low power bolometer arrays, with applications in far infrared imaging, spectroscopy and polarimetry, utilizes a superconducting bilayer as the sensing element to enable SQUID multiplexed readout. Superconducting transition edge sensors (TES s) are being produced with dual metal systems of superconductinghormal bilayers. The transition temperature (Tc) is tuned by altering the relative thickness of the superconductor with respect to the normal layer. We are currently investigating MoAu and MoCu bilayers. We have developed a dry-etching process for MoAu TES s with integrated molybdenum leads, and are working on adapting the process to MoCu. Dry etching has the advantage over wet etching in the MoAu system in that one can achieve a high degree of selectivity, greater than 10, using argon ME, or argon ion milling, for patterning gold on molybdenum. Molybdenum leads are subsequently patterned using fluorine plasma.. The dry-etch technique results in a smooth, featureless TES with sharp sidewalls, no undercutting of the Mo beneath the normal metal, and Mo leads with high critical current. The effects of individual processing parameters on the characteristics of the transition will be reported.

Studies of Impurities in the Pegasus Spherical Tokamak

NASA Astrophysics Data System (ADS)

Rodriguez Sanchez, C.; Bodner, G. M.; Bongard, M. W.; Burke, M. G.; Fonck, R. J.; Perry, J. M.; Reusch, J. A.; Weberski, J. D.

2017-10-01

Local Helicity Injection (LHI) is used to initiate ST plasmas without a solenoid. Testing predictive models for the evolution of Ip(t) during LHI requires measurement of the plasma resistivity to quantify the dissipation of helicity. To that end, three diagnostic systems are coupled with an impurity transport model to quantify plasma contaminants. These are: visible bremsstrahlung (VB) spectroscopy; bolometry; and VUV spectroscopy. A spectral survey has been performed to identify line-free regions for VB measurements in the visible. Initial VB measurements are obtained with a single sightline through the plasma, and will be expanded to an imaging array to provide spatial resolution. A SPRED multichannel VUV spectrometer is being upgraded to provide high-speed ( 0.2 ms) spectral surveys for ion species identification, with a high-resolution grating installed for metallic line identification. A 16-channel thinistor bolometer array is planned. Absolutely calibrated VB, bolometer measurements, and qualitative ion species identification from SPRED are used as constraints in an impurity transport code to estimate absolute impurity content. Earlier work using this general approach indicated Zeff < 3 , before the edge current sources were shielded to reduce plasma-injector interactions. Work supported by US DOE Grant DE-FG02-96ER54375.

Status of the CUORE and results from the CUORE-0 neutrinoless double beta decay experiments

DOE PAGES

Sisti, M.; Artusa, D. R.; Avignone, F. T.; ...

2016-05-31

CUORE is a 741 kg array of TeO 2 bolometers for the search of neutrinoless double beta decay of 130Te. The detector is being constructed at the Laboratori Nazionali del Gran Sasso, Italy, where it will start taking data in 2015. If the target background of 0.01 counts/(keV·kg·y) will be reached, in five years of data taking CUORE will have a 1σ half life sensitivity of 10 26y. CUORE-0 is a smaller experiment constructed to test and demonstrate the performances expected for CUORE. The detector is a single tower of 52 CUORE-like bolometers that started taking data in spring 2013.more » The status and perspectives of CUORE will be discussed, and the first CUORE-0 data will be presented.« less

Status of the CUORE and results from the CUORE-0 neutrinoless double beta decay experiments

NASA Astrophysics Data System (ADS)

Sisti, M.; Artusa, D. R.; Avignone, F. T.; Azzolini, O.; Balata, M.; Banks, T. I.; Bari, G.; Beeman, J.; Bellini, F.; Bersani, A.; Biassoni, M.; Brofferio, C.; Bucci, C.; Cai, X. Z.; Camacho, A.; Caminata, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Cappelli, L.; Carbone, L.; Cardani, L.; Casali, N.; Cassina, L.; Chiesa, D.; Chott, N.; Clemenza, M.; Copello, S.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Cushman, J. S.; Dafinei, I.; Dally, A.; Datskov, V.; Dell'Oro, S.; Deninno, M. M.; Di Domizio, S.; di Vacri, M. L.; Drobizhev, A.; Ejzak, L.; Fang, D. Q.; Farach, H. A.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Heeger, K. M.; Hennings-Yeomans, R.; Hickerson, K. P.; Huang, H. Z.; Kadel, R.; Keppel, G.; Kolomensky, Yu. G.; Li, Y. L.; Ligi, C.; Lim, K. E.; Liu, X.; Ma, Y. G.; Maiano, C.; Maino, M.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Napolitano, T.; Nastasi, M.; Nisi, S.; Nones, C.; Norman, E. B.; Nucciotti, A.; O'Donnell, T.; Orio, F.; Orlandi, D.; Ouellet, J. L.; Pagliarone, C. E.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pedretti, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, C.; Pirro, S.; Pozzi, S.; Previtali, E.; Rosenfeld, C.; Rusconi, C.; Sala, E.; Sangiorgio, S.; Scielzo, N. D.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tian, W. D.; Tomei, C.; Trentalange, S.; Ventura, G.; Vignati, M.; Wang, B. S.; Wang, H. W.; Wielgus, L.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zarra, C.; Zhang, G. Q.; Zhu, B. X.; Zucchelli, S.

2016-04-01

CUORE is a 741 kg array of TeO2 bolometers for the search of neutrinoless double beta decay of 130Te. The detector is being constructed at the Laboratori Nazionali del Gran Sasso, Italy, where it will start taking data in 2015. If the target background of 0.01 counts / (keV ṡkg ṡy) will be reached, in five years of data taking CUORE will have a 1σ half life sensitivity of 1026 y. CUORE-0 is a smaller experiment constructed to test and demonstrate the performances expected for CUORE. The detector is a single tower of 52 CUORE-like bolometers that started taking data in spring 2013. The status and perspectives of CUORE will be discussed, and the first CUORE-0 data will be presented.

Assembly and Integration Process of the First High Density Detector Array for the Atacama Cosmology Telescope

NASA Technical Reports Server (NTRS)

Li, Yaqiong; Choi, Steve; Ho, Shuay-Pwu; Crowley, Kevin T.; Salatino, Maria; Simon, Sara M.; Staggs, Suzanne T.; Nati, Federico; Wollack, Edward J.

2016-01-01

The Advanced ACTPol (AdvACT) upgrade on the Atacama Cosmology Telescope (ACT) consists of multichroicTransition Edge Sensor (TES) detector arrays to measure the Cosmic Microwave Background (CMB) polarization anisotropies in multiple frequency bands. The first AdvACT detector array, sensitive to both 150 and 230 GHz, is fabricated on a 150 mm diameter wafer and read out with a completely different scheme compared to ACTPol. Approximately 2000 TES bolometers are packed into the wafer leading to both a much denser detector density and readout circuitry. The demonstration of the assembly and integration of the AdvACT arrays is important for the next generation CMB experiments, which will continue to increase the pixel number and density. We present the detailed assembly process of the first AdvACT detector array.

Analysis of Camera Arrays Applicable to the Internet of Things.

PubMed

Yang, Jiachen; Xu, Ru; Lv, Zhihan; Song, Houbing

2016-03-22

The Internet of Things is built based on various sensors and networks. Sensors for stereo capture are essential for acquiring information and have been applied in different fields. In this paper, we focus on the camera modeling and analysis, which is very important for stereo display and helps with viewing. We model two kinds of cameras, a parallel and a converged one, and analyze the difference between them in vertical and horizontal parallax. Even though different kinds of camera arrays are used in various applications and analyzed in the research work, there are few discussions on the comparison of them. Therefore, we make a detailed analysis about their performance over different shooting distances. From our analysis, we find that the threshold of shooting distance for converged cameras is 7 m. In addition, we design a camera array in our work that can be used as a parallel camera array, as well as a converged camera array and take some images and videos with it to identify the threshold.

Optical characterization of ultra-sensitive TES bolometers for SAFARI

NASA Astrophysics Data System (ADS)

Audley, Michael D.; de Lange, Gerhard; Gao, Jian-Rong; Khosropanah, Pourya; Mauskopf, Philip D.; Morozov, Dmitry; Trappe, Neil A.; Doherty, Stephen; Withington, Stafford

2014-07-01

We have characterized the optical response of prototype detectors for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. SAFARI's three bolometer arrays will image a 2'×2' field of view with spectral information over the wavelength range 34—210 μm. SAFARI requires extremely sensitive detectors (goal NEP ~ 0.2 aW/√Hz), with correspondingly low saturation powers (~5 fW), to take advantage of SPICA's cooled optics. We have constructed an ultra-low background optical test facility containing an internal cold black-body illuminator and have recently added an internal hot black-body source and a light-pipe for external illumination. We illustrate the performance of the test facility with results including spectral-response measurements. Based on an improved understanding of the optical throughput of the test facility we find an optical efficiency of 60% for prototype SAFARI detectors.

Scalable Background-Limited Polarization-Sensitive Detectors for mm-wave Applications

NASA Technical Reports Server (NTRS)

Rostem, Karwan; Ali, Aamir; Appel, John W.; Bennett, Charles L.; Chuss, David T.; Colazo, Felipe A.; Crowe, Erik; Denis, Kevin L.; Essinger-Hileman, Tom; Marriage, Tobias A.;

High T(sub c) Superconducting Bolometer on Chemically Etched 7 Micrometer Thick Sapphire

NASA Technical Reports Server (NTRS)

Lakew, B.; Brasunas, J. C.; Pique, A.; Fettig, R.; Mott, B.; Babu, S.; Cushman, G. M.

1997-01-01

A transition-edge IR detector, using a YBa2Cu3O(7-x) (YBCO) thin film deposited on a chemically etched, 7 micrometer thick sapphire substrate has been built. To our knowledge it is the first such high T(sub c) superconducting (HTS) bolometer on chemically thinned sapphire. The peak optical detectivity obtained is l.2 x 10(exp 10) cmHz(sup 1/2)/W near 4Hz. Result shows that it is possible to obtain high detectivity with thin films on etched sapphire with no processing after the deposition of the YBCO film. We discuss the etching process and its potential for micro-machining sapphire and fabricating 2-dimensional detector arrays with suspended sapphire membranes. A 30 micrometer thick layer of gold black provided IR absorption. Comparison is made with the current state of the art on silicon substrates.

Three-dimensional tomographic imaging for dynamic radiation behavior study using infrared imaging video bolometers in large helical device plasma

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

Sano, Ryuichi; Iwama, Naofumi; Peterson, Byron J.

A three-dimensional (3D) tomography system using four InfraRed imaging Video Bolometers (IRVBs) has been designed with a helical periodicity assumption for the purpose of plasma radiation measurement in the large helical device. For the spatial inversion of large sized arrays, the system has been numerically and experimentally examined using the Tikhonov regularization with the criterion of minimum generalized cross validation, which is the standard solver of inverse problems. The 3D transport code EMC3-EIRENE for impurity behavior and related radiation has been used to produce phantoms for numerical tests, and the relative calibration of the IRVB images has been carried outmore » with a simple function model of the decaying plasma in a radiation collapse. The tomography system can respond to temporal changes in the plasma profile and identify the 3D dynamic behavior of radiation, such as the radiation enhancement that starts from the inboard side of the torus, during the radiation collapse. The reconstruction results are also consistent with the output signals of a resistive bolometer. These results indicate that the designed 3D tomography system is available for the 3D imaging of radiation. The first 3D direct tomographic measurement of a magnetically confined plasma has been achieved.« less

High resolution infrared acquisitions droning over the LUSI mud eruption.

NASA Astrophysics Data System (ADS)

Di Felice, Fabio; Romeo, Giovanni; Di Stefano, Giuseppe; Mazzini, Adriano

2016-04-01

The use of low-cost hand-held infrared (IR) thermal cameras based on uncooled micro-bolometer detector arrays became more widespread during the recent years. Thermal cameras have the ability to estimate temperature values without contact and therefore can be used in circumstances where objects are difficult or dangerous to reach such as volcanic eruptions. Since May 2006 the Indonesian LUSI mud eruption continues to spew boiling mud, water, aqueous vapor, CO2, CH4 and covers a surface of nearly 7 km2. At this locality we performed surveys over the unreachable erupting crater. In the framework of the LUSI Lab project (ERC grant n° 308126), in 2014 and 2015, we acquired high resolution infrared images using a specifically equipped remote-controlled drone flying at an altitude of m 100. The drone is equipped with GPS and an autopilot system that allows pre-programming the flying path or designing grids. The mounted thermal camera has peak spectral sensitivity in LW wavelength (μm 10) that is characterized by low water vapor and CO2 absorption. The low distance (high resolution) acquisitions have a temperature detail every cm 40, therefore it is possible to detect and observe physical phenomena such as thermodynamic behavior, hot mud and fluids emissions locations and their time shifts. Despite the harsh logistics and the continuously varying gas concentrations we managed to collect thermal images to estimate the crater zone spatial thermal variations. We applied atmosphere corrections to calculate infrared absorption by high concentration of water vapor. Thousands of images have been stitched together to obtain a mosaic of the crater zone. Regular monitoring with heat variation measurements collected, e.g. every six months, could give important information about the volcano activity estimating its evolution. A future data base of infrared high resolution and visible images stored in a web server could be a useful monitoring tool. An interesting development will be to use a multi-spectral thermal camera to perform a complete near remote sensing to detect, not only temperature, but gas, sensitive to particular wavelengths.

Sub-millimeter science with the Heinrich-Hertz-Telescope

NASA Astrophysics Data System (ADS)

Dumke, Michael

The Heinrich-Hertz-Telescope on Mt. Graham, Arizona, is a state-of-the-art single-dish radio telescope for observations in the sub-millimeter wavelength range. It is operated by the Sub-Millimeter Telescope Observatory (SMTO), which is a collaboration between the University of Arizona, Tucson, and the Max-Planck-Institut für Radioastronomie, Bonn. In this talk I give an overview over the telescope and its instrumentation, and show some examples of forefront research performed by astronomers from both the U.S. and Europe using this instrument. The telescope is located on Mt. Graham, Arizona, at an altitude of 3178 m, which ensures sub-mm weather conditions during a significant amount of available observing time. It has a primary reflector of 10 m diameter, mounted on a carbon fiber backup structure, and is equipped with a corotating enclosure. The surface accuracy of the primary reflector is 12 microns rms, what makes the HHT the most accurate radio telescope ever built. For spectral line observations, SIS receivers covering the frequency range from 200 to 500 GHz are available. Furthermore, a Hot-Electron-Bolometer, developed at the CfA, can be used for spectral line observations above 800 GHz. The continuum receivers are a 4-color bolometer, observing at 1300, 870, 450, and 350 microns, and a 19-channel bolometer array, developed at the MPIfR, which is sensitive around 850 microns. In the last few years, the HHT has been used by several groups to perform astronomical research. The most notable result was the measurement of the CO(9--8) line in Orion at 1.037 THz with the Hot-Electron Bolometer -- the first radioastronomical observation above 1 THz from a ground-based telescope. Several galactic molecular line sources have been mapped in the CO(7--6) line at 806 GHz, and in two fine-structure lines of atomic carbon. A continuum map of the galactic center at 850 microns could be produced using the new 19-channel bolometer array. Even external galaxies, where molecular line emission can be observed at much smaller brightness temperatures, could be mapped in the higher CO transitions. While CO(7--6) studies have been restricted to starburst galaxies like M 82 in the past, the CO(4--3) and especially the CO(3--2) line could be mapped also in fairly normal galaxies, showing that the warmer and denser gas is distributed throughout the galactic disks. Recently several nearby galaxies of different types could be mapped also in the continuum emission at 850 microns, allowing the determination of dust properties in various environments. Some interesting results following from observations with the Heinrich-Hertz-Telescope will be shown in this talk, with some emphasis on extragalactic astronomy.

An AzTEC 1.1mm survey of the GOODS-N field - II. Multiwavelength identifications and redshift distribution

NASA Astrophysics Data System (ADS)

Chapin, Edward L.; Pope, Alexandra; Scott, Douglas; Aretxaga, Itziar; Austermann, Jason E.; Chary, Ranga-Ram; Coppin, Kristen; Halpern, Mark; Hughes, David H.; Lowenthal, James D.; Morrison, Glenn E.; Perera, Thushara A.; Scott, Kimberly S.; Wilson, Grant W.; Yun, Min S.

2009-10-01

We present results from a multiwavelength study of 29 sources (false detection probabilities <5 per cent) from a survey of the Great Observatories Origins Deep Survey-North (GOODS-N) field at 1.1mm using the Astronomical Thermal Emission Camera (AzTEC). Comparing with existing 850μm Submillimetre Common-User Bolometer Array (SCUBA) studies in the field, we examine differences in the source populations selected at the two wavelengths. The AzTEC observations uniformly cover the entire survey field to a 1σ depth of ~1mJy. Searching deep 1.4GHz Very Large Array (VLA) and Spitzer 3-24μm catalogues, we identify robust counterparts for 21 1.1mm sources, and tentative associations for the remaining objects. The redshift distribution of AzTEC sources is inferred from available spectroscopic and photometric redshifts. We find a median redshift of z = 2.7, somewhat higher than z = 2.0 for 850μm selected sources in the same field, and our lowest redshift identification lies at a spectroscopic redshift z = 1.1460. We measure the 850μm to 1.1mm colour of our sources and do not find evidence for `850μm dropouts', which can be explained by the low signal-to-noise ratio of the observations. We also combine these observed colours with spectroscopic redshifts to derive the range of dust temperatures T, and dust emissivity indices β for the sample, concluding that existing estimates T ~ 30K and β ~ 1.75 are consistent with these new data.

Photonics and bioinspiration

NASA Astrophysics Data System (ADS)

Lewis, Keith

2014-10-01

Biological systems exploiting light have benefitted from thousands of years of genetic evolution and can provide insight to support the development of new approaches for imaging, image processing and communication. For example, biological vision systems can provide significant diversity, yet are able to function with only a minimal degree of neural processing. Examples will be described underlying the processes used to support the development of new concepts for photonic systems, ranging from uncooled bolometers and tunable filters, to asymmetric free-space optical communication systems and new forms of camera capable of simultaneously providing spectral and polarimetric diversity.

Ultrasensitive Superconducting Transition Edge Sensors Based On Electron-Phonon Decoupling

NASA Technical Reports Server (NTRS)

Jethava, Nikhil; Chervenak, James; Brown, Ari-David; Benford, Dominic; Kletetschka, Gunther; Mikula, Vilem; U-yen, Kongpop

2011-01-01

We have successfully fabricated the superconducting transition edge sensor (TES), bolometer technology that centers on the use of electron-phonon decoupling (EPD) to thermally isolate the bolometer. Along with material characterization for large format antenna coupled bolometer arrays, we present the initial test results of bolometer based on EPD designed for THz detection. We have selected a design approach that separates the two functions of photon absorption and temperature measurement, allowing separate optimization of the performance of each element. We have integrated Molybdenum/Gold (Mo/Au) bilayer TES and ion assisted thermally evaporated (IAE) Bismuth (Bi) films as radiation absorber coupled to a low-loss microstripline from Niobium (Nb) ground plane to a twin-slot antenna structure. The thermal conductance and the time constant of these devices have been measured, and are consistent with our calculations. The device exhibits a single time constant at 0.1 K of approx.160 IlS, which is compatible with readout by a high-bandwidth single SQUID or a time domain SQUID multiplexer. The effects of thermal conductance and electrothermal feedback are major determinants of the time constant, but the electronic heat capacity also plays a major role. The NEP achieved in the device described above is 2.5x10(exp -17)W(gamma)Hz. Our plan is to demonstrate a reduction of the volume in the superconducting element to 5 microns x 5 microns in films of half the thickness at Tc = 60mK. By calculation, this new geometry corresponds to an NEP reduction of two orders of magnitude to 2.5x10(exp -19)W/(gamma)Hz, with a time constant of 130/ls.

On-orbit solar calibrations using the Aqua Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system

NASA Astrophysics Data System (ADS)

Wilson, Robert S.; Priestley, Kory J.; Thomas, Susan; Hess, Phillip

2009-08-01

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometers were used to measure earth-reflected solar and earth-emitted longwave radiances, at satellite altitude. The bolometers measured the earth radiances in the broadband shortwave solar (0.3 - 5.0 micrometers) and total (0.3->100 micrometers) spectral bands as well as in the (8 - 12 micrometers) water vapor window spectral band over geographical footprints as small as 10 kilometers at nadir. In May 2002, the fourth and fifth sets of CERES bolometers were launched aboard the Aqua spacecraft. Ground vacuum calibrations defined the initial count conversion coefficients that were used to convert the bolometer output voltages into filtered earth radiances. The mirror attenuator mosaic (MAM), a solar diffuser plate, was built into the CERES instrument package calibration system in order to define in-orbit shifts or drifts in the sensor responses. The shortwave and total sensors are calibrated using the solar radiances reflected from the MAM's. Each MAM consists of baffle-solar diffuser plate systems, which guide incoming solar radiances into the instrument fields-of-view of the shortwave and total wave sensor units. The MAM diffuser reflecting type surface consists of an array of spherical aluminum mirror segments, which are separated by a Merck Black A absorbing surface, overcoated with silicon dioxide. Temperature sensors are located in each MAM plate and baffle. The CERES MAM wass designed to yield calibration precisions approaching .5 percent for the total and shortwave detectors. In this paper, the MAM solar calibration procedures are presented along with on-orbit results. Comparisons are also made between the Aqua,Terra and the Tropical Rainfall Measurement Mission (TRMM) CERES MAM solar calibrations.

Optical Characterization of the SPT-3G Focal Plane

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

Pan, Z.; et al.

The third-generation South Pole Telescope camera is designed to measure the cosmic microwave background across three frequency bands (95, 150 and 220 GHz) with ~16,000 transition-edge sensor (TES) bolometers. Each multichroic pixel on a detector wafer has a broadband sinuous antenna that couples power to six TESs, one for each of the three observing bands and both polarization directions, via lumped element filters. Ten detector wafers populate the focal plane, which is coupled to the sky via a large-aperture optical system. Here we present the frequency band characterization with Fourier transform spectroscopy, measurements of optical time constants, beam properties, andmore » optical and polarization efficiencies of the focal plane. The detectors have frequency bands consistent with our simulations, and have high average optical efficiency which is 86%, 77% and 66% for the 95, 150 and 220 GHz detectors. The time constants of the detectors are mostly between 0.5 ms and 5 ms. The beam is round with the correct size, and the polarization efficiency is more than 90% for most of the bolometers« less

A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment.

PubMed

Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi

2016-08-30

This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments.

Plenoptic camera image simulation for reconstruction algorithm verification

NASA Astrophysics Data System (ADS)

Schwiegerling, Jim

2014-09-01

Plenoptic cameras have emerged in recent years as a technology for capturing light field data in a single snapshot. A conventional digital camera can be modified with the addition of a lenslet array to create a plenoptic camera. Two distinct camera forms have been proposed in the literature. The first has the camera image focused onto the lenslet array. The lenslet array is placed over the camera sensor such that each lenslet forms an image of the exit pupil onto the sensor. The second plenoptic form has the lenslet array relaying the image formed by the camera lens to the sensor. We have developed a raytracing package that can simulate images formed by a generalized version of the plenoptic camera. Several rays from each sensor pixel are traced backwards through the system to define a cone of rays emanating from the entrance pupil of the camera lens. Objects that lie within this cone are integrated to lead to a color and exposure level for that pixel. To speed processing three-dimensional objects are approximated as a series of planes at different depths. Repeating this process for each pixel in the sensor leads to a simulated plenoptic image on which different reconstruction algorithms can be tested.

The subsurface of Pluto from submillimetre observations

NASA Astrophysics Data System (ADS)

Greaves, J. S.; Whitelaw, A. C. M.; Bendo, G. J.

2015-04-01

Surface areas on Pluto change in brightness and colour, at optical to infrared wavelengths, over time-scales as short as years. The subsurface contains a reservoir of frozen volatiles, but little is known about it because Pluto is out of reach for cm-radar. Here we present a 0.85 mm wavelength light curve of the Pluto system, from archival data taken in 1997 August with the SCUBA (Submillimetre Common-User Bolometer Array) camera on the James Clerk Maxwell Telescope (JCMT). This wavelength probes for the first time to just below the skin depth of thermal changes over Pluto's day. The light curve differs significantly from counterparts in the mid- to far-infrared, in a longitude range that is optically dark on Pluto's surface. An estimate from Herschel of the 0.5 mm flux in 2012 is comparable to the mean 0.45 mm flux from SCUBA in 1997, suggesting that layers centimetres below the surface have not undergone any gross temperature change. The longitudes that are relatively submillimetre-faint could have a different emissivity, perhaps with a subsurface layer richer in nitrogen or methane ices than at the surface. The Radio Science Experiment (REX) instrument on New Horizons may be able to constrain physical properties deeper down, as it looks back on Pluto's nightside after the 2015 July flyby.

Near-field observation platform

NASA Astrophysics Data System (ADS)

Schlemmer, Harry; Baeurle, Constantin; Vogel, Holger

2008-04-01

A miniaturized near-field observation platform is presented comprising a sensitive daylight camera and an uncooled micro-bolometer thermal imager each equipped with a wide angle lens. Both cameras are optimised for a range between a few meters and 200 m. The platform features a stabilised line of sight and can therefore be used also on a vehicle when it is in motion. The line of sight either can be directed manually or the platform can be used in a panoramic mode. The video output is connected to a control panel where algorithms for moving target indication or tracking can be applied in order to support the observer. The near-field platform also can be netted with the vehicle system and the signals can be utilised, e.g. to designate a new target to the main periscope or the weapon sight.

Large Format Arrays for Far Infrared and Millimeter Astronomy

NASA Technical Reports Server (NTRS)

Moseley, Harvey

2004-01-01

Some of the most compelling questions in modem astronomy are best addressed with submillimeter and millimeter observations. The question of the role of inflation in the early evolution of the universe is best addressed with large sensitive arrays of millimeter polarimeters. The study of the first generations of galaxies requires sensitive submillimeter imaging, which can help us to understand the history of energy release and nucleosynthesis in the universe. Our ability to address these questions is dramatically increasing, driven by dramatic steps in the sensitivity and size of available detector arrays. While the MIPS instrument on the SIRTF mission will revolutionize far infrared astronomy with its 1024 element array of photoconductors, thermal detectors remain the dominant technology for submillimeter and millimeter imaging and polarimetry. The last decade has seen the deployment of increasingly large arrays of bolometers, ranging from the 48 element arrays deployed on the KAO in the late 198Os, to the SHARC and SCUBA arrays in the 1990s. The past years have seen the deployment of a new generation of larger detector arrays in SHARC II (384 channels) and Bolocam (144 channels). These detectors are in operation and are beginning to make significant impacts on the field. Arrays of sensitive submillimeter bolometers on the SPIRE instrument on Herschel will allow the first large areas surveys of the sky, providing important insight into the evolution of galaxies. The next generation of detectors, led by SCUBA II, will increase the focal scale of these instruments by an order of magnitude. Two major missions are being planned by NASA for which further development of long wavelength detectors is essential, The SAFlR mission, a 10-m class telescope with large arrays of background limited detectors, will extend our reach into the epoch of initial galaxy formation. A major goal of modem cosmology is to test the inflationary paradigm in the early evolution of the universe. To this end, a mission is planned to detect the imprint of inflation on the CMB by precision measurement of its polarization. This work requires very large arrays of sensitive detectors which can provide unprecedented control of a wide range of systematic errors, given the small amplitude of the signal of interest. We will describe the current state of large format detector arrays, the performance requirements set by the new missions, and the different approaches being developed in the community to meet these requirements. We are confident that within a decade, these developments will lead to dramatic advances in our understanding of the evolution of the universe.

Design of the SAC-D/NIRST camera module

NASA Astrophysics Data System (ADS)

Gauvin, Jonny; Châteauneuf, François; Marchese, Linda; Coté, Patrice; Leclerc, Mélanie; Chevalier, Claude; Marraco, Hugo; Phong, Linh N.

2007-09-01

Aquarius/SAC-D is a cooperative international mission conducted jointly by the National Aeronautics and Space Administration (NASA) of the United States of America (USA) and the Comisión Nacional de Actividades Espaciales (CONAE) of Argentina. The overall mission targets the understanding of the total Earth system and the consequences of the natural and man-made changes in the environment of the planet. Jointly developed by CONAE and the Canadian Space Agency (CSA), the New IR Sensor Technology (NIRST) instrument will monitor high temperature events on the ground related to fires and volcanic events, and will measure their physical parameters. Furthermore, NIRST will take measurements of sea surface temperatures mainly off the coast of South America as well as other targeted opportunities. NIRST has one band in the mid-wave infrared centered at 3.8 um with a bandwidth of 0.8 um, and two bands in the thermal infrared, centered respectively at 10.85 and 11.85 um with a bandwidth of 0.9 um. The temperature range is from 300 to 600 K with an NEDT < 0.5 K for the mid-infrared band and from 200 to 400 K with an NEDT < 0.4 K for the thermal bands. The baseline design of the NIRST is based on micro-bolometer technology developed jointly by INO and the CSA. Two arrays of 512x3 uncooled bolometric sensors will be used to measure brightness temperatures. The instantaneous field-of-view is 534 microradians corresponding to a ground sampling distance of 350 m at the subsatellite point. A pointing mirror allows a total swath of +/- 500 km. This paper describes the detailed design of the NIRST camera module. Key performance parameters are also presented.

Uncooled infrared focal plane array imaging in China

NASA Astrophysics Data System (ADS)

Lei, Shuyu

2015-06-01

This article reviews the development of uncooled infrared focal plane array (UIFPA) imaging in China in the past decade. Sensors based on optical or electrical read-out mechanism were developed but the latter dominates the market. In resistive bolometers, VOx and amorphous silicon are still the two major thermal-sensing materials. The specifications of the IRFPA made by different manufactures were collected and compared. Currently more than five Chinese companies and institutions design and fabricate uncooled infrared focal plane array. Some devices have sensitivity as high as 30 mK; the largest array for commercial products is 640×512 and the smallest pixel size is 17 μm. Emphasis is given on the pixel MEMS design, ROIC design, fabrication, and packaging of the IRFPA manufactured by GWIC, especially on design for high sensitivities, low noise, better uniformity and linearity, better stabilization for whole working temperature range, full-digital design, etc.

A novel carbon coating technique for foil bolometers

NASA Astrophysics Data System (ADS)

Sheikh, U. A.; Duval, B. P.; Labit, B.; Nespoli, F.

2016-11-01

Naked foil bolometers can reflect a significant fraction of incident energy and therefore cannot be used for absolute measurements. This paper outlines a novel coating approach to address this problem by blackening the surface of gold foil bolometers using physical vapour deposition. An experimental bolometer was built containing four standard gold foil bolometers, of which two were coated with 100+ nm of carbon. All bolometers were collimated and observed the same relatively high temperature, ohmically heated plasma. Preliminary results showed 13%-15% more incident power was measured by the coated bolometers and this is expected to be much higher in future TCV detached divertor experiments.

Mini Compton Camera Based on an Array of Virtual Frisch-Grid CdZnTe Detectors

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

Lee, Wonho; Bolotnikov, Aleksey; Lee, Taewoong

In this study, we constructed a mini Compton camera based on an array of CdZnTe detectors and assessed its spectral and imaging properties. The entire array consisted of 6×6 Frisch-grid CdZnTe detectors, each with a size of 6×6 ×15 mm 3. Since it is easier and more practical to grow small CdZnTe crystals rather than large monolithic ones, constructing a mosaic array of parallelepiped crystals can be an effective way to build a more efficient, large-volume detector. With the fully operational CdZnTe array, we measured the energy spectra for 133Ba -, 137Cs -, 60Co-radiation sources; we also located these sourcesmore » using a Compton imaging approach. Although the Compton camera was small enough to hand-carry, its intrinsic efficiency was several orders higher than those generated in previous researches using spatially separated arrays, because our camera measured the interactions inside the CZT detector array, wherein the detector elements were positioned very close to each other. Lastly, the performance of our camera was compared with that based on a pixelated detector.« less

Mini Compton Camera Based on an Array of Virtual Frisch-Grid CdZnTe Detectors

DOE PAGES

Lee, Wonho; Bolotnikov, Aleksey; Lee, Taewoong; ...

2016-02-15

In this study, we constructed a mini Compton camera based on an array of CdZnTe detectors and assessed its spectral and imaging properties. The entire array consisted of 6×6 Frisch-grid CdZnTe detectors, each with a size of 6×6 ×15 mm 3. Since it is easier and more practical to grow small CdZnTe crystals rather than large monolithic ones, constructing a mosaic array of parallelepiped crystals can be an effective way to build a more efficient, large-volume detector. With the fully operational CdZnTe array, we measured the energy spectra for 133Ba -, 137Cs -, 60Co-radiation sources; we also located these sourcesmore » using a Compton imaging approach. Although the Compton camera was small enough to hand-carry, its intrinsic efficiency was several orders higher than those generated in previous researches using spatially separated arrays, because our camera measured the interactions inside the CZT detector array, wherein the detector elements were positioned very close to each other. Lastly, the performance of our camera was compared with that based on a pixelated detector.« less

The SOFIA/SAFIRE Far-Infrared Spectrometer: Highlighting Submillimeter Astrophysics and Technology

NASA Technical Reports Server (NTRS)

Benford, Dominic J.

2009-01-01

The Submillimeter and Far-InfraRed Experiment (SAFIRE) on the SOFIA airborne observatory is an imaging spectrometer for wavelengths between 28 microns and 440 microns. Our design is a dual-band long-slit grating spectrometer, which provides broadband (approx. 4000 km/s) observations in two lines simultaneously over a field of view roughly 10" wide by 320" long. The low backgrounds in spectroscopy require very sensitive detectors with noise equivalent powers of order 10(exp -18) W/square root of Hz. We are developing a kilopixel, filled detector array for SAFIRE in a 32 x 40 format. The detector consists of a transition edge sensor (TES) bolometer array, a per-pixel broadband absorbing backshort array, and a NIST SQUID multiplexer readout array. This general type of array has been used successfully in the GISMO instrument, so we extrapolate to the sensitivity needed for airborne spectroscopy. Much of the cryogenic, electronics, and software infrastructure for SAFIRE have been developed. I provide here an overview of the progress on SAFIRE.

Nonimaging applications for microbolometer arrays

NASA Astrophysics Data System (ADS)

Picard, Francis; Jerominek, Hubert; Pope, Timothy D.; Zhang, Rose; Ngo, Linh P.; Tremblay, Bruno; Tasker, Nick; Grenier, Carol; Bilodeau, Ghislain; Cayer, Felix; Lehoux, Mario; Alain, Christine; Larouche, Carl; Savard, Simon

2001-10-01

In an effort to leverage uncooled microbolometer technology, testing of bolometer performance in various nonimaging applications has been performed. One of these applications makes use of an uncooled microbolometer array as the sensing element for a laser beam analyzer. Results of the characterization of cw CO2 laser beams with this analyzer are given. A comparison with the results obtained with a commercial laser beam analyzer is made. Various advantages specific to microbolometer arrays for this application are identified. A second application makes use of microbolometers for absolute temperature measurements. The experimental method and results are described. The technique's limitations and possible implementations are discussed. Finally, the third application evaluated is related to the rapidly expanding field of biometry. It consists of using a modified microbolometer array for fingerprint sensing. The basic approach allowing the use of microbolometers for such an application is discussed. The results of a proof-of-principle experiment are described. Globally, the described work illustrates the fact that microbolometer array fabrication technology can be exploited for many important applications other than IR imaging.

A combined microphone and camera calibration technique with application to acoustic imaging.

PubMed

Legg, Mathew; Bradley, Stuart

2013-10-01

We present a calibration technique for an acoustic imaging microphone array, combined with a digital camera. Computer vision and acoustic time of arrival data are used to obtain microphone coordinates in the camera reference frame. Our new method allows acoustic maps to be plotted onto the camera images without the need for additional camera alignment or calibration. Microphones and cameras may be placed in an ad-hoc arrangement and, after calibration, the coordinates of the microphones are known in the reference frame of a camera in the array. No prior knowledge of microphone positions, inter-microphone spacings, or air temperature is required. This technique is applied to a spherical microphone array and a mean difference of 3 mm was obtained between the coordinates obtained with this calibration technique and those measured using a precision mechanical method.

Transition-edge superconducting antenna-coupled bolometer

NASA Astrophysics Data System (ADS)

Hunt, Cynthia L.

2004-10-01

The temperature anisotropy of the cosmic microwave background (CMB) is now being probed with unprecedented accuracy and sky coverage by the Wilkinson Microwave Anisotropy Probe (WMAP), and will be definitively mapped by the Planck Surveyor after its launch in 2007. However, the polarization of the CMB will not be mapped with sufficient accuracy. In particular, the measurement of the curl-polarization, which may be used to probe the energy scale of the inflationary epoch, requires a large advance in the format of millimeter-wave bolometer arrays. SAMBA (Superconducting Antenna-coupled Multi-frequency Bolometric Array) is being developed to address these needs for the next generation of submillimeter astronomical detectors. SAMBA consists of a focal plane populated with microstrip-coupled slot antennas, whose signals are coherently added and sent to transition-edge superconducting (TES) bolometers via microstrip lines. SAMBA eliminates the need for the feedhorns and optical filters currently used on CMB observational instruments, such as Planck and Boomerang. The SAMBA architecture allows for a high density of pixels in the focal plane with minimal sub-Kelvin mass. As a precursor to a full monolithic high-density antenna array, we are developing a single-band antenna-coupled Bolometric detector. In this thesis, I report test results for a single-pixel antenna-coupled Bolometric detector. Our device consists of a dual slot microstrip-coupled slot antenna coupled to an Al/Ti/Au voltage-biased TES. The coupling architecture involves propagating the signal along super conducting microstrip lines and terminating the lines at a normal metal resistor collocated with a TES on a thermally isolated island. The device, which is inherently polarization sensitive, is optimized for 140 GHz measurements. In the thermal bandwidth of the TES, we measure a noise equivalent power (NEP) of 2.0 x 10 -17 W/[Special characters omitted.] in dark tests which agrees with the calculated NEP including only contributions from phonon; Johnson and amplifier noise. We do not measure any excess noise above this expectation at frequencies between 1 and 200 Hz. We measure a thermal conductance G = 55 pW/K. We measure a thermal time constant as low as 437 ms at 3 mV bias when stimulating the TES directly using a light emitting diode.

Automated Camera Array Fine Calibration

NASA Technical Reports Server (NTRS)

Clouse, Daniel; Padgett, Curtis; Ansar, Adnan; Cheng, Yang

2008-01-01

Using aerial imagery, the JPL FineCalibration (JPL FineCal) software automatically tunes a set of existing CAHVOR camera models for an array of cameras. The software finds matching features in the overlap region between images from adjacent cameras, and uses these features to refine the camera models. It is not necessary to take special imagery of a known target and no surveying is required. JPL FineCal was developed for use with an aerial, persistent surveillance platform.

Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors

DOE PAGES

Artusa, D. R.; Azzolini, O.; Balata, M.; ...

2014-10-15

Neutrinoless double beta decay (0νββ) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0νββ decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric0νββ experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capablemore » of reaching the sensitivity to the effective Majorana neutrino mass (|m ee|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. In conclusion, we highlight the main challenges and identify priorities for an R&D program addressing them.« less

Polarimetry with the JCMT

NASA Astrophysics Data System (ADS)

Moriarty-Schieven, Gerald H.; Greaves, Jane S.

1999-10-01

Polarization of dust or synchrotron emission in the sub-millimetre-wave regime directly traces magnetic field directions. The magnetic field energy is similar to that of gravity and turbulence in interstellar gas, and so plays a major role in the dynamics and evolution of the interstellar medium. We present some early results from the aperture polarimeter on the SCUBA sub-mm bolometer array on the JCMT from a wide variety of sources, and briefly discuss the importance of a polarimetric capability for ALMA.

Double-beta decay investigation with highly pure enriched $$^{82}$$Se for the LUCIFER experiment

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

Beeman, J. W.; Bellini, F.; Benetti, P.

2015-12-13

The LUCIFER project aims at deploying the first array of enriched scintillating bolometers for the investigation of neutrinoless double-beta decay of 82Se. The matrix which embeds the source is an array of ZnSe crystals, where enriched 82Se is used as decay isotope. The radiopurity of the initial components employed for manufacturing crystals, that can be operated as bolometers, is crucial for achieving a null background level in the region of interest for double-beta decay investigations. In this work, we evaluated the radioactive content in 2.5 kg of 96.3 % enriched 82Se metal, measured with a high-purity germanium detector at themore » Gran Sasso deep underground laboratory. The limits on internal contaminations of primordial decay chain elements of 232Th, 238U and 235U are respectively: <61, <110 and <74 μBq/kg at 90 % C.L. The extremely low-background conditions in which the measurement was carried out and the high radiopurity of the 82Se allowed us to establish the most stringent lower limits on the half-lives of the double-beta decay of 82Se to 0+1, 2+2 and 2+1 excited states of 82Kr of 3.4•10 22, 1.3•10 22 and 1.0•10 22 y, respectively, with a 90 % C.L.« less

Lateral terahertz hot-electron bolometer based on an array of Sn nanothreads in GaAs

NASA Astrophysics Data System (ADS)

Ponomarev, D. S.; Lavrukhin, D. V.; Yachmenev, A. E.; Khabibullin, R. A.; Semenikhin, I. E.; Vyurkov, V. V.; Ryzhii, M.; Otsuji, T.; Ryzhii, V.

2018-04-01

We report on the proposal and the theoretical and experimental studies of the terahertz hot-electron bolometer (THz HEB) based on a gated GaAs structure like the field-effect transistor with the array of parallel Sn nanothreads (Sn-NTs). The operation of the HEB is associated with an increase in the density of the delocalized electrons due to their heating by the incoming THz radiation. The quantum and the classical device models were developed, the quantum one was based on the self-consistent solution of the Poisson and Schrödinger equations, the classical model involved the Poisson equation and density of states omitting quantization. We calculated the electron energy distributions in the channels formed around the Sn-NTs for different gate voltages and found the fraction of the delocalized electrons propagating across the energy barriers between the NTs. Since the fraction of the delocalized electrons strongly depends on the average electron energy (effective temperature), the proposed THz HEB can exhibit an elevated responsivity compared with the HEBs based on more standard heterostructures. Due to a substantial anisotropy of the device structure, the THz HEB may demonstrate a noticeable polarization selectivity of the response to the in-plane polarized THz radiation. The features of the THz HEB might be useful in their practical applications in biology, medicine and material science.

Comparison of the temperature accuracy between smart phone based and high-end thermal cameras using a temperature gradient phantom

NASA Astrophysics Data System (ADS)

Klaessens, John H.; van der Veen, Albert; Verdaasdonk, Rudolf M.

2017-03-01

Recently, low cost smart phone based thermal cameras are being considered to be used in a clinical setting for monitoring physiological temperature responses such as: body temperature change, local inflammations, perfusion changes or (burn) wound healing. These thermal cameras contain uncooled micro-bolometers with an internal calibration check and have a temperature resolution of 0.1 degree. For clinical applications a fast quality measurement before use is required (absolute temperature check) and quality control (stability, repeatability, absolute temperature, absolute temperature differences) should be performed regularly. Therefore, a calibrated temperature phantom has been developed based on thermistor heating on both ends of a black coated metal strip to create a controllable temperature gradient from room temperature 26 °C up to 100 °C. The absolute temperatures on the strip are determined with software controlled 5 PT-1000 sensors using lookup tables. In this study 3 FLIR-ONE cameras and one high end camera were checked with this temperature phantom. The results show a relative good agreement between both low-cost and high-end camera's and the phantom temperature gradient, with temperature differences of 1 degree up to 6 degrees between the camera's and the phantom. The measurements were repeated as to absolute temperature and temperature stability over the sensor area. Both low-cost and high-end thermal cameras measured relative temperature changes with high accuracy and absolute temperatures with constant deviations. Low-cost smart phone based thermal cameras can be a good alternative to high-end thermal cameras for routine clinical measurements, appropriate to the research question, providing regular calibration checks for quality control.

Method and apparatus for coherent imaging of infrared energy

DOEpatents

Hutchinson, D.P.

1998-05-12

A coherent camera system performs ranging, spectroscopy, and thermal imaging. Local oscillator radiation is combined with target scene radiation to enable heterodyne detection by the coherent camera`s two-dimensional photodetector array. Versatility enables deployment of the system in either a passive mode (where no laser energy is actively transmitted toward the target scene) or an active mode (where a transmitting laser is used to actively illuminate the target scene). The two-dimensional photodetector array eliminates the need to mechanically scan the detector. Each element of the photodetector array produces an intermediate frequency signal that is amplified, filtered, and rectified by the coherent camera`s integrated circuitry. By spectroscopic examination of the frequency components of each pixel of the detector array, a high-resolution, three-dimensional or holographic image of the target scene is produced for applications such as air pollution studies, atmospheric disturbance monitoring, and military weapons targeting. 8 figs.

A progress report on using bolometers cooled by adiabatic demagnetization refrigeration

NASA Technical Reports Server (NTRS)

Lesyna, L.; Roellig, T.; Savage, M.; Werner, Michael W.

1989-01-01

For sensitive detection of astronomical continuum radiation in the 200 micron to 3 mm wavelength range, bolometers are presently the detectors of choice. In order to approach the limits imposed by photon noise in a cryogenically cooled telescope in space, bolometers must be operated at temperatures near 0.1 K. Researchers report progress in building and using bolometers that operate at these temperatures. The most sensitive bolometer had an estimated noise equivalent power (NEP) of 7 x 10(exp 017) W Hz(exp -1/2). Researchers also briefly discuss the durability of paramagnetic salts used to cool the bolometers.

Superconducting hot electron bolometers for terahertz sensing

NASA Astrophysics Data System (ADS)

Reese, Matthew Owen

Superconducting Hot Electron Bolometers (HEBs) are good candidates for detecting weak signals in the submillimeter or terahertz range. In this thesis work, a novel fabrication method was developed to make two types of niobium HEBs for different applications. HEBs were designed, fabricated, and then characterized at dc, microwave, and THz frequencies. The first type is a diffusion-cooled HEB, made with a short bridge that determines its cooling time. In this thesis, bridges were typically 400 nm long with bandwidths of about 1 GHz. These diffusion-cooled HEBs were developed as part of a collaboration with the University of Arizona (UA), to develop a proof-of-concept heterodyne array submillimeter camera. Devices were fabricated on thin fused quartz and silica substrates for waveguide coupling in the UA system for the astrophysically interesting 345 and 810 GHz atmospheric windows. The goal of this collaboration is to provide a basis of comparison between Nb diffusion-cooled HEB mixers and superconductorinsulator-superconductor mixers at these frequencies. The second type is a phonon-cooled HEB, made with a ˜3 mum long bridge. Its thermal response is dictated by the electron-phonon relaxation time. These devices were developed in collaboration with Prof. C. Schmuttenmaer's lab in the Yale Chemistry department, Prof. G. Blake at Caltech, and Dr. J. Pearson at the Jet Propulsion Laboratory. These devices were developed for use in quasi-optic systems to be used as fast (>100 MHz) direct detectors that can view room temperature sources without saturating. A variety of experimental applications are envisioned for these detectors including charge transport measurements of novel materials. A series of dc and microwave measurements were performed on the diffusion-cooled devices. A better understanding of the resistance vs. temperature profile was realized, including what design/fabrication parameters affect it and insight into how it affects device performance. This led to a do screening process that can identify good quality devices. The Nb phonon-cooled HEBs studied in this thesis were fully carried through the design, fabrication, and characterization process at dc, microwave and THz frequencies. The saturation power, responsivity, thermal response time, and noise performance were all measured to be within the expected range predicted by the initial design parameters.

VizieR Online Data Catalog: Photometry of the transient event iPTF16fnl (Blagorodnova+, 2017)

NASA Astrophysics Data System (ADS)

Blagorodnova, N.; Gezari, S.; Hung, T.; Kulkarni, S. R.; Cenko, S. B.; Pasham, D. R.; Yan, L.; Arcavi, I.; Ben-Ami, S.; Bue, B. D.; Cantwell, T.; Cao, Y.; Castro-Tirado, A. J.; Fender, R.; Fremling, C.; Gal-Yam, A.; Ho, A. Y. Q.; Horesh, A.; Hosseinzadeh, G.; Kasliwal, M. M.; Kong, A. K. H.; Laher, R. R.; Leloudas, G.; Lunnan, R.; Masci, F. J.; Mooley, K.; Neill, J. D.; Nugent, P.; Powell, M.; Valeev, A. F.; Vreeswijk, P. M.; Walters, R.; Wozniak, P.

2018-03-01

On the night after discovery (2016 August 29th), we observed the source with the FLOYDS spectrograph on the Las Cumbres Observatory (LCO) 2m telescope and the Spectral Energy Distribution Machine (SEDM) on the Palomar 60 inch (P60) telescope. The SEDM is a ultra-low resolution (R~100) integral-field-unit (IFU) spectrograph. Following spectroscopic identification of iPTF16fnl as a tidal disruption event (TDE) candidate, the source was monitored at Palomar and by the Ultraviolet and Optical Telescope (UVOT) on board the Swift observatory. The UVOT observations were taken in UVW2, UVM2, UVW1, U, B, and V. At Palomar, photometry in the g and Mould-R bands were obtained with the iPTF mosaic wide-field camera on the Palomar 48-inch telescope (P48). Table 3 reports the measured Swift aperture photometry magnitudes and the difference-imaging photometry for the Palomar data spanning 2016 Aug to 2016 Dec. Radio follow-up observations of iPTF16fnl were taken with the Jansky Very Large Array (VLA; PI A. Horesh), the Arcminute Microkelvin Imager (AMI; PI K. Mooley) and the James Clerk Maxwell Telescope and the Submillimetre Common-User Bolometer Array 2 (JCMT/SCUBA-2; PI A. K. H. Kong). We also observed the location of iPTF16fnl with the X-Ray Telescope (XRT) on board the Swift satellite beginning at 19:32 UT on 30 August 2016. Regular monitoring of the field in photon counting mode continued over the course of the next four months (PIs T. Holoien and B. Cenko). (1 data file).

Hierarchical sinuous-antenna phased array for millimeter wavelengths

NASA Astrophysics Data System (ADS)

Cukierman, Ari; Lee, Adrian T.; Raum, Christopher; Suzuki, Aritoki; Westbrook, Benjamin

2018-03-01

We present the design, fabrication, and measured performance of a hierarchical sinuous-antenna phased array coupled to superconducting transition-edge-sensor (TES) bolometers for millimeter wavelengths. The architecture allows for dual-polarization wideband sensitivity with a beam width that is approximately frequency-independent. We report on measurements of a prototype device, which uses three levels of triangular phased arrays to synthesize beams that are approximately constant in width across three frequency bands covering a 3:1 bandwidth. The array element is a lens-coupled sinuous antenna. The device consists of an array of hemispherical lenses coupled to a lithographed wafer, which integrates TESs, planar sinuous antennas, and microwave circuitry including band-defining filters. The approximately frequency-independent beam widths improve coupling to telescope optics and keep the sensitivity of an experiment close to optimal across a broad frequency range. The design can be straightforwardly modified for use with non-TES lithographed cryogenic detectors such as kinetic inductance detectors. Additionally, we report on the design and measurements of a broadband 180° hybrid that can simplify the design of future multichroic focal planes including but not limited to hierarchical phased arrays.

Relating transverse ray error and light fields in plenoptic camera images

NASA Astrophysics Data System (ADS)

Schwiegerling, Jim; Tyo, J. Scott

2013-09-01

Plenoptic cameras have emerged in recent years as a technology for capturing light field data in a single snapshot. A conventional digital camera can be modified with the addition of a lenslet array to create a plenoptic camera. The camera image is focused onto the lenslet array. The lenslet array is placed over the camera sensor such that each lenslet forms an image of the exit pupil onto the sensor. The resultant image is an array of circular exit pupil images, each corresponding to the overlying lenslet. The position of the lenslet encodes the spatial information of the scene, whereas as the sensor pixels encode the angular information for light incident on the lenslet. The 4D light field is therefore described by the 2D spatial information and 2D angular information captured by the plenoptic camera. In aberration theory, the transverse ray error relates the pupil coordinates of a given ray to its deviation from the ideal image point in the image plane and is consequently a 4D function as well. We demonstrate a technique for modifying the traditional transverse ray error equations to recover the 4D light field of a general scene. In the case of a well corrected optical system, this light field is easily related to the depth of various objects in the scene. Finally, the effects of sampling with both the lenslet array and the camera sensor on the 4D light field data are analyzed to illustrate the limitations of such systems.

Development of infrared scene projectors for testing fire-fighter cameras

NASA Astrophysics Data System (ADS)

Neira, Jorge E.; Rice, Joseph P.; Amon, Francine K.

2008-04-01

We have developed two types of infrared scene projectors for hardware-in-the-loop testing of thermal imaging cameras such as those used by fire-fighters. In one, direct projection, images are projected directly into the camera. In the other, indirect projection, images are projected onto a diffuse screen, which is then viewed by the camera. Both projectors use a digital micromirror array as the spatial light modulator, in the form of a Micromirror Array Projection System (MAPS) engine having resolution of 800 x 600 with mirrors on a 17 micrometer pitch, aluminum-coated mirrors, and a ZnSe protective window. Fire-fighter cameras are often based upon uncooled microbolometer arrays and typically have resolutions of 320 x 240 or lower. For direct projection, we use an argon-arc source, which provides spectral radiance equivalent to a 10,000 Kelvin blackbody over the 7 micrometer to 14 micrometer wavelength range, to illuminate the micromirror array. For indirect projection, an expanded 4 watt CO II laser beam at a wavelength of 10.6 micrometers illuminates the micromirror array and the scene formed by the first-order diffracted light from the array is projected onto a diffuse aluminum screen. In both projectors, a well-calibrated reference camera is used to provide non-uniformity correction and brightness calibration of the projected scenes, and the fire-fighter cameras alternately view the same scenes. In this paper, we compare the two methods for this application and report on our quantitative results. Indirect projection has an advantage of being able to more easily fill the wide field of view of the fire-fighter cameras, which typically is about 50 degrees. Direct projection more efficiently utilizes the available light, which will become important in emerging multispectral and hyperspectral applications.

HFI Bolometer Detectors Programmatic CDR

NASA Technical Reports Server (NTRS)

Lange, Andrew E.

2002-01-01

Programmatic Critical Design Review (CDR) of the High Frequency Instrument (HFI) Bolometer Detector on the Planck Surveyor is presented. The topics include: 1) Scientific Requirements and Goals; 2) Silicon Nitride Micromesh 'Spider-Web' Bolometers; 3) Sub-Orbital Heritage: BOOMERANG; 4) Noise stability demonstrated in BOOMERANG; 5) Instrument Partners; 6) Bolometer Environment on Planck/HFI; 7) Bolometer Modules; and 8) Mechanical Interface. Also included are the status of the receivables and delivery plans with Europe. This paper is presented in viewgraph form.

Coordinated Instruments for Source Detection and Characterization

NASA Astrophysics Data System (ADS)

Wilson, G. W.

2007-10-01

I describe two instruments designed for coordinated observations of the submillimeter galaxy population. AzTEC is a 144-element bolometer camera designed to survey fields and detect submillimeter galaxies in the 1.1 mm band. In June of 2005, AzTEC completed a successful engineering run at the JCMT. The instrument then returned to the JCMT in October for a series of science programs, which will result in a set of catalogs of the submillimeter galaxy population that span a wide range of environments. SPEED is a 4-pixel photometer that uses frequency selective bolometers to observe in four colors simultaneously in each pixel (for a total of 16 detectors). SPEED will be used for follow-up observations of sources found by AzTEC as well as for the measurement of the Sunyaev-Zel'dovich effect in clusters. SPEED's band centers are 2.1 mm, 1.4 mm, 1.1 mm, and 0.85 mm. Because each color is observed through the same optics, the relative calibration of the four bands will be excellent. SPEED is under construction now with a planned deployment to the SMT in 2006. These two instruments will eventually be installed at the LMT as facility instruments.

Developments in mercuric iodide gamma ray imaging

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

Patt, B.E.; Beyerle, A.G.; Dolin, R.C.

A mercuric iodide gamma-ray imaging array and camera system previously described has been characterized for spatial and energy resolution. Based on this data a new camera is being developed to more fully exploit the potential of the array. Characterization results and design criterion for the new camera will be presented. 2 refs., 7 figs.

The Primordial Inflation Polarization Explorer (PIPER)

NASA Technical Reports Server (NTRS)

Chuss, David

2010-01-01

The Primordial Inflation Polarization Explorer (PIPER) is a balloon-borne polarimeter that will measure the polarization of the cosmic microwave background to search for evidence for inflation. PIPER will observe more than half of the sky in four frequency bands from 200 to 600 GHz with a beam size of 21 arcminutes at the lowest frequency. PIPER simultaneously measures all four Stokes parameters using four co-aligned 32 by 40 element planar bolometer arrays. We give an instrument overview and report on the current status of the instrument.

The ORAC-DR data reduction pipeline

NASA Astrophysics Data System (ADS)

Cavanagh, B.; Jenness, T.; Economou, F.; Currie, M. J.

2008-03-01

The ORAC-DR data reduction pipeline has been used by the Joint Astronomy Centre since 1998. Originally developed for an infrared spectrometer and a submillimetre bolometer array, it has since expanded to support twenty instruments from nine different telescopes. By using shared code and a common infrastructure, rapid development of an automated data reduction pipeline for nearly any astronomical data is possible. This paper discusses the infrastructure available to developers and estimates the development timescales expected to reduce data for new instruments using ORAC-DR.

Woven ribbon cable for cryogenic instruments

NASA Astrophysics Data System (ADS)

Cunningham, C. R.; Hastings, P. R.; Strachan, J. M. D.

Robust woven ribbon cables are described for connecting sensors at low temperatures to higher temperature systems. Woven cables have several advantages over conventional wiring or flat ribbon cables in cryostats: heat sinking is easier; twisted pairs may be used; and miniature multi-way connectors are easily incorporated. Their use is demonstrated in making connections from 131 bolometers in two arrays mounted in a dilution refrigerator at 100 mK. Thermal and electrical properties are discussed, as are other possible applications in cryogenic instruments.

The mass distribution of clumps within infrared dark clouds. A Large APEX Bolometer Camera study

NASA Astrophysics Data System (ADS)

Gómez, L.; Wyrowski, F.; Schuller, F.; Menten, K. M.; Ballesteros-Paredes, J.

2014-01-01

Aims: We present an analysis of the dust continuum emission at 870 μm in order to investigate the mass distribution of clumps within infrared dark clouds (IRDCs). Methods: We map six IRDCs with the Large APEX BOlometer CAmera (LABOCA) at APEX, reaching an rms noise level of σrms = 28-44 mJy beam-1. The dust continuum emission coming from these IRDCs was decomposed by using two automated algorithms, Gaussclumps and Clumpfind. Moreover, we carried out single-pointing observations of the N2H+ (3-2) line toward selected positions to obtain kinematic information. Results: The mapped IRDCs are located in the range of kinematic distances of 2.7-3.2 kpc. We identify 510 and 352 sources with Gaussclumps and Clumpfind, respectively, and estimate masses and other physical properties assuming a uniform dust temperature. The mass ranges are 6-2692 M⊙ (Gaussclumps) and 7-4254 M⊙ (Clumpfind), and the ranges in effective radius are ~0.10-0.74 pc (Gaussclumps) and 0.16-0.99 pc (Clumpfind). The mass distribution, independent of the decomposition method used, is fitted by a power law, dN/dM ∝ Mα, with an index (α) of -1.60 ± 0.06, consistent with the CO mass distribution and other high-mass star-forming regions. Based on data acquired with the Atacama Pathfinder Experiment (APEX). APEX is a collaboration between the Max-Planck-Institut für Radioastronomie, the European Southern Observatory, and the Onsala Space Observatory.Full Tables 3 and 4 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A148

Efficient Broadband Terahertz Radiation Detectors Based on Bolometers with a Thin Metal Absorber

NASA Astrophysics Data System (ADS)

Dem'yanenko, M. A.

2018-01-01

The matrix method has been used to calculate the coefficients of absorption of terahertz radiation in conventional (with radiation incident from vacuum adjacent to the bolometer) and inverted (with radiation incident from the substrate on which the bolometer was fabricated) bolometric structures. Near-unity absorption coefficients were obtained when an additional cavity in the form of a gap between the bolometer and the input or output window was introduced. Conventional bolometers then became narrowband, while inverted-type devices remained broadband.

MMW/THz imaging using upconversion to visible, based on glow discharge detector array and CCD camera

NASA Astrophysics Data System (ADS)

Aharon, Avihai; Rozban, Daniel; Abramovich, Amir; Yitzhaky, Yitzhak; Kopeika, Natan S.

2017-10-01

An inexpensive upconverting MMW/THz imaging method is suggested here. The method is based on glow discharge detector (GDD) and silicon photodiode or simple CCD/CMOS camera. The GDD was previously found to be an excellent room-temperature MMW radiation detector by measuring its electrical current. The GDD is very inexpensive and it is advantageous due to its wide dynamic range, broad spectral range, room temperature operation, immunity to high power radiation, and more. An upconversion method is demonstrated here, which is based on measuring the visual light emitting from the GDD rather than its electrical current. The experimental setup simulates a setup that composed of a GDD array, MMW source, and a basic CCD/CMOS camera. The visual light emitting from the GDD array is directed to the CCD/CMOS camera and the change in the GDD light is measured using image processing algorithms. The combination of CMOS camera and GDD focal plane arrays can yield a faster, more sensitive, and very inexpensive MMW/THz camera, eliminating the complexity of the electronic circuits and the internal electronic noise of the GDD. Furthermore, three dimensional imaging systems based on scanning prohibited real time operation of such imaging systems. This is easily solved and is economically feasible using a GDD array. This array will enable us to acquire information on distance and magnitude from all the GDD pixels in the array simultaneously. The 3D image can be obtained using methods like frequency modulation continuous wave (FMCW) direct chirp modulation, and measuring the time of flight (TOF).

NectarCAM, a camera for the medium sized telescopes of the Cherenkov telescope array

NASA Astrophysics Data System (ADS)

Glicenstein, J.-F.; Shayduk, M.

2017-01-01

NectarCAM is a camera proposed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) which covers the core energy range of 100 GeV to 30 TeV. It has a modular design and is based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 8 degrees. Each module includes photomultiplier bases, high voltage supply, pre-amplifier, trigger, readout and Ethernet transceiver. The recorded events last between a few nanoseconds and tens of nanoseconds. The expected performance of the camera are discussed. Prototypes of NectarCAM components have been built to validate the design. Preliminary results of a 19-module mini-camera are presented, as well as future plans for building and testing a full size camera.

Concept Doped-Silicon Thermopile Detectors for Future Planetary Thermal Imaging Instruments

NASA Astrophysics Data System (ADS)

Lakew, Brook; Barrentine, Emily M.; Aslam, Shahid; Brown, Ari D.

2016-10-01

Presently, uncooled thermopiles are the detectors of choice for thermal mapping in the 4.6-100 μm spectral range. Although cooled detectors like Ge or Si thermistor bolometers, and MgB2 or YBCO superconducting bolometers, have much higher sensitivity, the required active or passive cooling mechanisms add prohibitive cost and mass for long duration missions. Other uncooled detectors, likepyroelectrics, require a motor mechanism to chop against a known reference temperature, which adds unnecessary mission risk. Uncooled vanadium oxide or amorphous Si microbolometer arrays with integrated CMOS readout circuits, not only have lower sensitivity, but also have not been proven to be radiation hard >100 krad (Si) total ionizing dose, and barring additional materials and readout development, their performance has reached a plateau.Uncooled and radiation hard thermopiles with D* ~1x109 cm√Hz/W and time constant τ ~100 ms have been integrated into thermal imaging instruments on several past missions and have extensive flight heritage (Mariner, Voyager, Cassini, LRO, MRO). Thermopile arrays are also on the MERTIS instrument payload on-board the soon to be launched BepiColombo Mission.To date, thermopiles used for spaceflight instrumentation have consisted of either hand assembled "one-off" single thermopile pixels or COTS thermopile pixel arrays both using Bi-Sb or Bi-Te thermoelectric materials. For future high performance imagers, thermal detector arrays with higher D*, lower τ, and high efficiency delineated absorbers are desirable. Existing COTS and other flight thermopile designs require highly specialized and nonstandard processing techniques to fabricate both the Bi-Sb or Bi-Te thermocouples and the gold or silver black absorbers, which put limitations on further development.Our detector arrays will have a D* ≥ 3x109 cm√Hz/W and a thermal time constant ≤ 30 ms at 170 K. They will be produced using proven, standard semiconductor and MEMS fabrication techniques, which will enable the future integration of other ancillary structures like high efficiency broadband absorbers, which will result in D* ≥ 5x109 cm√Hz/W.

Facility Instrumentation for SOFIA: Technical Specifications and Scientific Goals

NASA Astrophysics Data System (ADS)

Stacey, G. J.

2000-05-01

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is NASA's next generation airborne observatory consisting of a 2.5 m telescope in a modified Boeing 747 SP. First light is expected in late 2002. Three "Facility Class" instruments were among the first generation of instruments selected to fly on SOFIA. These instruments, currently under development are (1) a 5 to 38 um imaging photometer based on twin As:Si and Sb:Sb BIB arrays (FORCAST), (2) a 40 to 300 um photometer based on three arrays of bolometers, and (3) a 17 to 210 um eschelle grating spectrometer based on an Sb:Sb BIB array and a Ge:Sb and stressed Ge:Ga array of photoconductors. I will discuss both the technical aspects of these facility instruments, and some of the exciting new science that is possible with these ground breaking instruments on an airborne 2.5 meter telescope. Science topics include circumstellar debris disks, star formation, the Galactic Center, and distant galaxies.

Fulfilling the pedestrian protection directive using a long-wavelength infrared camera designed to meet both performance and cost targets

NASA Astrophysics Data System (ADS)

Källhammer, Jan-Erik; Pettersson, Håkan; Eriksson, Dick; Junique, Stéphane; Savage, Susan; Vieider, Christian; Andersson, Jan Y.; Franks, John; Van Nylen, Jan; Vercammen, Hans; Kvisterøy, Terje; Niklaus, Frank; Stemme, Göran

2006-04-01

Pedestrian fatalities are around 15% of the traffic fatalities in Europe. A proposed EU regulation requires the automotive industry to develop technologies that will substantially decrease the risk for Vulnerable Road Users when hit by a vehicle. Automatic Brake Assist systems, activated by a suitable sensor, will reduce the speed of the vehicle before the impact, independent of any driver interaction. Long Wavelength Infrared technology is an ideal candidate for such sensors, but requires a significant cost reduction. The target necessary for automotive serial applications are well below the cost of systems available today. Uncooled bolometer arrays are the most mature technology for Long Wave Infrared with low-cost potential. Analyses show that sensor size and production yield along with vacuum packaging and the optical components are the main cost drivers. A project has been started to design a new Long Wave Infrared system with a ten times cost reduction potential, optimized for the pedestrian protection requirement. It will take advantage of the progress in Micro Electro-Mechanical Systems and Long Wave Infrared optics to keep the cost down. Deployable and pre-impact braking systems can become effective alternatives to passive impact protection systems solutions fulfilling the EU pedestrian protection regulation. Low-cost Long Wave Infrared sensors will be an important enabler to make such systems cost competitive, allowing high market penetration.

SCD's uncooled detectors and video engines for a wide-range of applications

NASA Astrophysics Data System (ADS)

Fraenkel, A.; Mizrahi, U.; Bikov, L.; Giladi, A.; Shiloah, N.; Elkind, S.; Kogan, I.; Maayani, S.; Amsterdam, A.; Vaserman, I.; Duman, O.; Hirsh, Y.; Schapiro, F.; Tuito, A.; Ben-Ezra, M.

2011-06-01

Over the last decade SCD has established a state of the art VOx μ-Bolometer product line. Due to its overall advantages this technology is penetrating a large range of systems. In addition to a large variety of detectors, SCD has also recently introduced modular video engines with an open architecture. In this paper we will describe the versatile applications supported by the products based on 17μm pitch: Low SWaP short range systems, mid range systems based on VGA arrays and high-end systems that will utilize the XGA format. These latter systems have the potential to compete with cooled 2nd Gen scanning LWIR arrays, as will be demonstrated by TRM3 system level calculations.

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This close-up view of one of two Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Antenna-coupled TES bolometer arrays for CMB polarimetry

NASA Astrophysics Data System (ADS)

Kuo, C. L.; Bock, J. J.; Bonetti, J. A.; Brevik, J.; Chattopadhyay, G.; Day, P. K.; Golwala, S.; Kenyon, M.; Lange, A. E.; LeDuc, H. G.; Nguyen, H.; Ogburn, R. W.; Orlando, A.; Transgrud, A.; Turner, A.; Wang, G.; Zmuidzinas, J.

2008-07-01

We describe the design and performance of polarization selective antenna-coupled TES arrays that will be used in several upcoming Cosmic Microwave Background (CMB) experiments: SPIDER, BICEP-2/SPUD. The fully lithographic polarimeter arrays utilize planar phased-antennas for collimation (F/4 beam) and microstrip filters for band definition (25% bandwidth). These devices demonstrate high optical efficiency, excellent beam shapes, and well-defined spectral bands. The dual-polarization antennas provide well-matched beams and low cross polarization response, both important for high-fidelity polarization measurements. These devices have so far been developed for the 100 GHz and 150 GHz bands, two premier millimeter-wave atmospheric windows for CMB observations. In the near future, the flexible microstrip-coupled architecture can provide photon noise-limited detection for the entire frequency range of the CMBPOL mission. This paper is a summary of the progress we have made since the 2006 SPIE meeting in Orlando, FL.

Testing of 100 mK bolometers for space applications

NASA Technical Reports Server (NTRS)

Murray, A. G.; Ade, P. A. R.; Bhatia, R. S.; Griffin, M. J.; Maffei, B.; Nartallo, R.; Beeman, J. W.; Bock, J.; Lange, A.; DelCastillo, H.

1996-01-01

Electrical and optical performance data are presented for a prototype 100 mK spider-web bolometer operating under very low photon backgrounds. These data are compared with the bolometer theory and are used to estimate the expected sensitivity of such a detector used for low background space astronomy. The results demonstrate that the sensitivity and speed of response requirements of the bolometer instruments proposed for these missions can be met by 100 mK spider-web bolometers using neutron transmutation doped germanium as the temperature sensitive element.

A Graphene-Based Terahertz Hot Electron Bolometer with Johnson Noise Readout

NASA Astrophysics Data System (ADS)

Miao, W.; Gao, H.; Wang, Z.; Zhang, W.; Ren, Y.; Zhou, K. M.; Shi, S. C.; Yu, C.; He, Z. Z.; Liu, Q. B.; Feng, Z. H.

2018-05-01

In this paper, we present the development of a graphene-based hot electron bolometer with Johnson noise readout. The bolometer is a graphene microbridge connected to a log spiral antenna by Au contact pads. The Fourier transform spectrometer measurement shows the bolometer has high coupling efficiency in the frequency range from 0.3 to 1.6 THz. Using 300/77 K blackbody loads, we measure an optical noise equivalent power of 5.6 × 10-12 W/Hz0.5 at 3.0 K. To understand the thermal transport inside the graphene microbridge, we measure the bolometers with different microbridge lengths at different bath temperatures. We find that the thermal conductance due to electron diffusion is significant in the bolometers.

The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

NASA Technical Reports Server (NTRS)

Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.;

The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

NASA Astrophysics Data System (ADS)

Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Henderson, S. W.; Hilton, G. C.; Hubmayr, J.; Koopman, B. J.; Lanen, J. V.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Ward, J. T.; Wollack, E. J.; Vavagiakis, E. M.

2016-08-01

The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive receiver for the 6-m Atacama Cosmology Telescope (ACT) and measures the small angular scale polarization anisotropies in the cosmic microwave background (CMB). The full focal plane is composed of three detector arrays, containing over 3000 transition edge sensors (TES detectors) in total. The first two detector arrays, observing at 146 GHz, were deployed in 2013 and 2014, respectively. The third and final array is composed of multichroic pixels sensitive to both 90 and 146 GHz and saw first light in February 2015. Fabricated at NIST, this dichroic array consists of 255 pixels, with a total of 1020 polarization sensitive bolometers and is coupled to the telescope with a monolithic array of broad-band silicon feedhorns. The detectors are read out using time-division SQUID multiplexing and cooled by a dilution refrigerator at 110 mK. We present an overview of the assembly and characterization of this multichroic array in the lab, and the initial detector performance in Chile. The detector array has a TES detector electrical yield of 85 %, a total array sensitivity of less than 10 \\upmu K√{ {s}}, and detector time constants and saturation powers suitable for ACT CMB observations.

Readout of a 176 pixel FDM system for SAFARI TES arrays

NASA Astrophysics Data System (ADS)

Hijmering, R. A.; den Hartog, R.; Ridder, M.; van der Linden, A. J.; van der Kuur, J.; Gao, J. R.; Jackson, B.

2016-07-01

In this paper we present the results of our 176-pixel prototype of the FDM readout system for SAFARI, a TES-based focal-plane instrument for the far-IR SPICA mission. We have implemented the knowledge obtained from the detailed study on electrical crosstalk reported previously. The effect of carrier leakage is reduced by a factor two, mutual impedance is reduced to below 1 nH and mutual inductance is removed. The pixels are connected in stages, one quarter of the array half of the array and the full array, to resolve intermediate technical issues. A semi-automated procedure was incorporated to find all optimal settings for all pixels. And as a final step the complete array has been connected and 132 pixels have been read out simultaneously within the frequency range of 1-3.8MHz with an average frequency separation of 16kHz. The noise was found to be detector limited and was not affected by reading out all pixels in a FDM mode. With this result the concept of using FDM for multiplexed bolometer read out for the SAFARI instrument has been demonstrated.

Double biprism arrays design using for stereo-photography of mobile phone camera

NASA Astrophysics Data System (ADS)

Sun, Wen-Shing; Chu, Pu-Yi; Chao, Yu-Hao; Pan, Jui-Wen; Tien, Chuen-Lin

2016-11-01

Generally, mobile phone use one camera to catch the image, and it is hard to get stereo image pair. Adding a biprism array can help that get the image pair easily. So users can use their mobile phone to catch the stereo image anywhere by adding a biprism array, and if they want to get a normal image just remove it. Using biprism arrays will induce chromatic aberration. Therefore, we design a double biprism arrays to reduce chromatic aberration.

A Kinematic, Kevlar(registered) Suspension System for an ADR

NASA Technical Reports Server (NTRS)

Voellmer, George M.; Jackson, Michael L.; Shirron, Peter J.; Tuttle, James G.

2003-01-01

The High Resolution Airborne Wideband Camera (HAWC) and the Submillimeter And Far Infrared Experiment (SAFIRE) will use identical Adiabatic Demagnetization Refrigerators (ADR) to cool their bolometer detectors to 200mK and 100mK, respectively. In order to minimize thermal loads on the salt pill, a Kevlar@ suspension system is used to hold it in place. An innovative, kinematic suspension system is presented. The suspension system is unique in that it consists or two parts that can be assembled and tensioned offline, and later bolted onto the salt pill. The resulting assembly constrains each degree of freedom only once, yielding a kinematic, tensile structure.

Arrays of Nano Tunnel Junctions as Infrared Image Sensors

NASA Technical Reports Server (NTRS)

Son, Kyung-Ah; Moon, Jeong S.; Prokopuk, Nicholas

2006-01-01

Infrared image sensors based on high density rectangular planar arrays of nano tunnel junctions have been proposed. These sensors would differ fundamentally from prior infrared sensors based, variously, on bolometry or conventional semiconductor photodetection. Infrared image sensors based on conventional semiconductor photodetection must typically be cooled to cryogenic temperatures to reduce noise to acceptably low levels. Some bolometer-type infrared sensors can be operated at room temperature, but they exhibit low detectivities and long response times, which limit their utility. The proposed infrared image sensors could be operated at room temperature without incurring excessive noise, and would exhibit high detectivities and short response times. Other advantages would include low power demand, high resolution, and tailorability of spectral response. Neither bolometers nor conventional semiconductor photodetectors, the basic detector units as proposed would partly resemble rectennas. Nanometer-scale tunnel junctions would be created by crossing of nanowires with quantum-mechanical-barrier layers in the form of thin layers of electrically insulating material between them (see figure). A microscopic dipole antenna sized and shaped to respond maximally in the infrared wavelength range that one seeks to detect would be formed integrally with the nanowires at each junction. An incident signal in that wavelength range would become coupled into the antenna and, through the antenna, to the junction. At the junction, the flow of electrons between the crossing wires would be dominated by quantum-mechanical tunneling rather than thermionic emission. Relative to thermionic emission, quantum mechanical tunneling is a fast process.

Multiplexing of Hot-Electron Nanobolometers Using Microwave SQUIDs

NASA Technical Reports Server (NTRS)

Karasik, Boris S.; Day, Peter K.; Kawamura, Jonathan H.; Bumble, Bruce; LeDuc, Henry G.

2009-01-01

We have obtained the first data on the multiplexed operation of titanium hot-electron bolometers (HEB). Because of their low thermal conductance and small electron heat capacity nanobolometers are particularly interesting as sensors for far-infrared spectroscopy and mid- and near-IR calorimetry. However, the short time constant of these devices (approximately microseconds at 300-400 mK) makes time domain or audio-frequency domain multiplexing impractical. The Microwave SQUID (MSQUID) approach pursued in this work uses dc SQUIDs coupled to X-band microresonators which are, in turn, coupled to a transmission line. We used a 4-element array of Ti HEBs operated at 415 mK in a He3 dewar with an optical fiber access. The microwave signal exhibited 10-MHz wide resonances at individual MSQUD frequencies between 9 GHz and 10 GHz. The resonance depth is modulated by the current through the bolometer via a change of the SQUID flux state. The transmitted signal was amplified by a cryogenic amplifier and downconverted to baseband using an IQ mixer. A 1-dB per ??/2 responsivity was sufficient for keeping the system noise at the level of 2 pA/Hz1/2. This is more than an order of magnitude smaller than phonon noise in the HEB. The devices were able to detect single near- IR photons (1550 nm) with a time constant of 3.5 ?s. Follow-on work will scale the array to larger size and will address the microwave frequency signal generation and processing using a digital transceiver.

Improved fabrication techniques for infrared bolometers

NASA Technical Reports Server (NTRS)

Lange, A. E.; Mcbride, S. E.; Richards, P. L.; Haller, E. E.; Kreysa, E.

1983-01-01

Ion implantation and sputter metallization are used to produce ohmic electrical contacts to Ge:Ga chips. The method is shown to give a high yield of small monolithic bolometers with very little low-frequency noise. It is noted that when one of the chips is used as the thermometric element of a composite bolometer it must be bonded to a dielectric substrate. The thermal resistance of the conventional epoxy bond is measured and found to be undesirably large. A procedure for soldering the chip to a metallized portion of the substrate in such a way as to reduce this resistance is outlined. An evaluation is made of the contribution of the metal film absorber to the heat capacity of a composite bolometer. It is found that the heat capacity of a NiCr absorber at 1.3 K can dominate the bolometer performance. A Bi absorber possesses significantly lower heat capacity. A low-temperature blackbody calibrator is built to measure the optical responsivity of bolometers. A composite bolometer system with a throughput of approximately 0.1 sr sq cm is constructed using the new techniques. The noise in this bolometer is white above 2.5 Hz and is slightly below the value predicted by thermodynamic equilibrium theory.

Fabrication of multi-focal microlens array on curved surface for wide-angle camera module

NASA Astrophysics Data System (ADS)

Pan, Jun-Gu; Su, Guo-Dung J.

2017-08-01

In this paper, we present a wide-angle and compact camera module that consists of microlens array with different focal lengths on curved surface. The design integrates the principle of an insect's compound eye and the human eye. It contains a curved hexagonal microlens array and a spherical lens. Compared with normal mobile phone cameras which usually need no less than four lenses, but our proposed system only uses one lens. Furthermore, the thickness of our proposed system is only 2.08 mm and diagonal full field of view is about 100 degrees. In order to make the critical microlens array, we used the inkjet printing to control the surface shape of each microlens for achieving different focal lengths and use replication method to form curved hexagonal microlens array.

Evaluation of multispectral plenoptic camera

NASA Astrophysics Data System (ADS)

Meng, Lingfei; Sun, Ting; Kosoglow, Rich; Berkner, Kathrin

2013-01-01

Plenoptic cameras enable capture of a 4D lightfield, allowing digital refocusing and depth estimation from data captured with a compact portable camera. Whereas most of the work on plenoptic camera design has been based a simplistic geometric-optics-based characterization of the optical path only, little work has been done of optimizing end-to-end system performance for a specific application. Such design optimization requires design tools that need to include careful parameterization of main lens elements, as well as microlens array and sensor characteristics. In this paper we are interested in evaluating the performance of a multispectral plenoptic camera, i.e. a camera with spectral filters inserted into the aperture plane of the main lens. Such a camera enables single-snapshot spectral data acquisition.1-3 We first describe in detail an end-to-end imaging system model for a spectrally coded plenoptic camera that we briefly introduced in.4 Different performance metrics are defined to evaluate the spectral reconstruction quality. We then present a prototype which is developed based on a modified DSLR camera containing a lenslet array on the sensor and a filter array in the main lens. Finally we evaluate the spectral reconstruction performance of a spectral plenoptic camera based on both simulation and measurements obtained from the prototype.

Dynamic Electrothermal Model of a Sputtered Thermopile Thermal Radiation Detector for Earth Radiation Budget Applications

NASA Technical Reports Server (NTRS)

Weckmann, Stephanie

1997-01-01

The Clouds and the Earth's Radiant Energy System (CERES) is a program sponsored by the National Aeronautics and Space Administration (NASA) aimed at evaluating the global energy balance. Current scanning radiometers used for CERES consist of thin-film thermistor bolometers viewing the Earth through a Cassegrain telescope. The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently studying a new sensor concept to replace the current bolometer: a thermopile thermal radiation detector. This next-generation detector would consist of a thermal sensor array made of thermocouple junction pairs, or thermopiles. The objective of the current research is to perform a thermal analysis of the thermopile. Numerical thermal models are particularly suited to solve problems for which temperature is the dominant mechanism of the operation of the device (through the thermoelectric effect), as well as for complex geometries composed of numerous different materials. Feasibility and design specifications are studied by developing a dynamic electrothermal model of the thermopile using the finite element method. A commercial finite element-modeling package, ALGOR, is used.

Status of LUMINEU program to search for neutrinoless double beta decay of 100Mo with cryogenic ZnMoO4 scintillating bolometers

NASA Astrophysics Data System (ADS)

Danevich, F. A.; Bergé, L.; Boiko, R. S.; Chapellier, M.; Chernyak, D. M.; Coron, N.; Devoyon, L.; Drillien, A.-A.; Dumoulin, L.; Enss, C.; Fleischmann, A.; Gastaldo, L.; Giuliani, A.; Gray, D.; Gros, M.; Hervé, S.; Humbert, V.; Ivanov, I. M.; Juillard, A.; Kobychev, V. V.; Koskas, F.; Loidl, M.; Magnier, P.; Makarov, E. P.; Mancuso, M.; de Marcillac, P.; Marnieros, S.; Marrache-Kikuchi, C.; Navick, X.-F.; Nones, C.; Olivieri, E.; Paul, B.; Penichot, Y.; Pessina, G.; Plantevin, O.; Poda, D. V.; Redon, T.; Rodrigues, M.; Shlegel, V. N.; Strazzer, O.; Tenconi, M.; Torres, L.; Tretyak, V. I.; Vasiliev, Ya. V.; Velazquez, M.; Viraphong, O.

2015-10-01

The LUMTNEU program aims at performing a pilot experiment on 0ν2β decay of 100Mo using radiopure ZnMoO4 crystals enriched in 100Mo operated as cryogenic scintillating bolometers. Large volume ZnMoO4 crystal scintillators (˜ 0.3 kg) were developed and tested showing high performance in terms of radiopurity, energy resolution and α/β particle discrimination capability. Zinc molybdate crystal scintillators enriched in 100Mo were grown for the first time by the low-thermal-gradient Czochralski technique with a high crystal yield and an acceptable level of enriched molybdenum irrecoverable losses. A background level of ˜ 0.5 counts/(yr keV ton) in the region of interest can be reached in a large detector array thanks to the excellent detectors radiopurity and particle discrimination capability, suppression of randomly coinciding events by pulse-shape analysis, and anticoincidence cut. These results pave the way to future sensitive searches based on the LUMTNEU technology, capable of approachingand exploring the inverted hierarchy region of the neutrino mass pattern.

TeO$$_2$$ bolometers with Cherenkov signal tagging: towards next-generation neutrinoless double-beta decay experiments

DOE PAGES

Casali, N.; Vignati, Marco; Beeman, J. W.; ...

2015-01-14

CUORE, an array of 988 TeOmore » $$_2$$ bolometers, is about to be one of the most sensitive experiments searching for neutrinoless double-beta decay. Its sensitivity could be further improved by removing the background from α radioactivity. A few years ago it was pointed out that the signal from βs can be tagged by detecting the emitted Cherenkov light, which is not produced by αs. In this paper we confirm this possibility. For the first time we measured the Cherenkov light emitted by a CUORE crystal, and found it to be 100 eV at the Q-value of the decay. To completely reject the α background, we compute that one needs light detectors with baseline noise below 20 eV RMS, a value which is 3–4 times smaller than the average noise of the bolometric light detectors we are using. We point out that an improved light detector technology must be developed to obtain TeO$$_2$$ bolometric experiments able to probe the inverted hierarchy of neutrino masses.« less

Single lens 3D-camera with extended depth-of-field

NASA Astrophysics Data System (ADS)

Perwaß, Christian; Wietzke, Lennart

2012-03-01

Placing a micro lens array in front of an image sensor transforms a normal camera into a single lens 3D camera, which also allows the user to change the focus and the point of view after a picture has been taken. While the concept of such plenoptic cameras is known since 1908, only recently the increased computing power of low-cost hardware and the advances in micro lens array production, have made the application of plenoptic cameras feasible. This text presents a detailed analysis of plenoptic cameras as well as introducing a new type of plenoptic camera with an extended depth of field and a maximal effective resolution of up to a quarter of the sensor resolution.

Characterization and Performance of a Kilo-TES Sub-Array for ACTPol

NASA Technical Reports Server (NTRS)

Grace, E. A.; Beall, J.; Cho, H. M.; Devlin, M. J.; Fox, A.; Hilton, G.; Hubmayr, J.; Irwin, K.; Klein, J.; Li, D.;

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This view, backdropped against the blackness of space shows one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST). The scene was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Considerations on thermal effects in doped scintillators for dark matter and other rare events searches

NASA Astrophysics Data System (ADS)

Chapellier, M.

2009-08-01

The scintillation properties of luminescent crystals are well known at room temperature. It is only recently, for the sake of dark matter and rare events searches that the studies have been extended to very low temperatures in the millikelvin range. Some little-known facts on the behaviour of bolometers , and more specifically on scintillating ones, are recalled in a simple manner. A few experiments to better understand them are proposed. The term bolometer is used here for calorimeter. Normally a bolometer will measure a flux of energy whereas a calorimeter measures a deposited energy. The tendency is to use bolometer for both types of measurement. A germanium bolometer does not measure the total energy received, part of it is transformed in ionization energy. The same is true for scintillating bolometer.

Improved fabrication techniques for infrared bolometers

NASA Technical Reports Server (NTRS)

Lange, A. E.; Kreysa, E.; Mcbride, S. E.; Richards, P. L.; Haller, E. E.

1983-01-01

Techniques are described for producing improved infrared bolometers from doped germanium. Ion implantation and sputter metalization have been used to make ohmic electrical contacts to Ge:Ga chips. This method results in a high yield of small monolithic bolometers with very little low-frequency noise. When one of these chips is used as the thermometric element of a composite bolometer, it must be bonded to a dielectric substrate. The thermal resistance of the conventional epoxy bond has been measured and found to be undesirably large. A procedure for soldering the chip to a metalized portion of the substrate is described which reduced this resistance. The contribution of the metal film absorber to the heat capacity of a composite bolometer has been measured. The heat capacity of a NiCr absorber at 1.3 K can dominate the bolometer performance. A Bi absorber has significantly lower heat capacity. A low temperature blackbody calibrator has been built to measure the optical responsivity of bolometers. A composite bolometer system with a throughput of approx. 0.1 sr sq cm was constructed using the new techniques. In negligible background it has an optical NEP of 3.6 10((exp -15) W/sq root of Hz at 1.0 K with a time constant of 20 ms. The noise in this bolometer is white above 2.5 Hz and is somewhat below the value predicted by thermodynamic equilibrium theory. It is in agreement with calculations based on a recent nonequilibrium theory.

Performance of Backshort-Under-Grid Kilopixel TES Arrays for HAWC+

NASA Technical Reports Server (NTRS)

Staguhn, J. G.; Benford, D. J.; Dowell, C. D.; Fixsen, D. J.; Hilton, G. C.; Irwin, K. D.; Jhabvala, C. A.; Maher, S. F.; Miller, T. M.; Moseley, S. H.;

An electrically tunable plenoptic camera using a liquid crystal microlens array.

PubMed

Lei, Yu; Tong, Qing; Zhang, Xinyu; Sang, Hongshi; Ji, An; Xie, Changsheng

2015-05-01

Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated with an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF.

An electrically tunable plenoptic camera using a liquid crystal microlens array

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

Lei, Yu; School of Automation, Huazhong University of Science and Technology, Wuhan 430074; Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074

2015-05-15

Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated withmore » an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF.« less

An electrically tunable plenoptic camera using a liquid crystal microlens array

NASA Astrophysics Data System (ADS)

Lei, Yu; Tong, Qing; Zhang, Xinyu; Sang, Hongshi; Ji, An; Xie, Changsheng

2015-05-01

Plenoptic cameras generally employ a microlens array positioned between the main lens and the image sensor to capture the three-dimensional target radiation in the visible range. Because the focal length of common refractive or diffractive microlenses is fixed, the depth of field (DOF) is limited so as to restrict their imaging capability. In this paper, we propose a new plenoptic camera using a liquid crystal microlens array (LCMLA) with electrically tunable focal length. The developed LCMLA is fabricated by traditional photolithography and standard microelectronic techniques, and then, its focusing performance is experimentally presented. The fabricated LCMLA is directly integrated with an image sensor to construct a prototyped LCMLA-based plenoptic camera for acquiring raw radiation of targets. Our experiments demonstrate that the focused region of the LCMLA-based plenoptic camera can be shifted efficiently through electrically tuning the LCMLA used, which is equivalent to the extension of the DOF.

Ground Calibrations of the Clouds and the Earth's Radiant Energy System (CERES) Tropical Rainfall Measuring Mission Spacecraft Thermistor Bolometers

NASA Technical Reports Server (NTRS)

Lee, Robert B., III; Smith, G. Lou; Barkstrom, Bruce R.; Priestley, Kory J.; Thomas, Susan; Paden, Jack; Pandey, Direndra K.; Thornhill, K. Lee; Bolden, William C.; Wilson, Robert S.

1997-01-01

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometers will measure earth-reflected solar and earth-emmitted,longwave radiances, at the top-of-the-atmosphere. The measurements are performed in the broadband shortwave (0.3-5.0 micron) and longwave (5.0 - >100 micron) spectral regions as well as in the 8 -12 micron water vapor window over geographical footprints as small as 10 kilometers at the nadir. The CERES measurements are designed to improve our knowledge of the earth's natural climate processes, in particular those related to clouds, and man's impact upon climate as indicated by atmospheric temperature. November 1997, the first set of CERES bolometers is scheduled for launch on the Tropical Rainfall Measuring Mission (TRMM) Spacecraft. The CERES bolometers were calibrated radiometrically in a vacuum ground facility using absolute reference sources, tied to the International Temperature Scale of 1990. Accurate bolometer calibrations are dependent upon the derivations of the radiances from the spectral properties [reflectance, transmittance, emittance, etc.] of both the sources and bolometers. In this paper, the overall calibration approaches are discussed for the longwave and shortwave calibrations. The spectral responses for the TRMM bolometer units are presented and applied to the bolometer ground calibrations in order to determine pre-launch calibration gains.

Superconducting bolometers for millimeter and sub-millimeter wavelengths

NASA Astrophysics Data System (ADS)

Jethava, N.; Kreysa, E.; Siringo, G.; Esch, W.; Gemünd, H.-P.; Menten, K. M.; May, T.; Anders, S.; Fritzsch, L.; Boucher, R.; Zakosarenko, V.; Meyer, H.-G.

2008-07-01

We present the experimental results and a bolometer model of the voltage-biased superconducting bolometer on the low stress silicon nitride (Si3N4) membrane, developed in collaboration between the Max-Planck-Institut fur Radioastronomie (MPIfR), Bonn and the Institute for Photonic Technology (IPHT), Jena, Germany. The superconducting thermistor, deposited on the low stress silicon nitride membrane, is a bilayer of gold-palladium and molybdenum and is designed for a transition temperature of 450 mK. Bolometers for the 1.2 mm atmospheric window were designed, built and tested. The thermal conductance of the bolometer is tuned by structuring the silicon nitride membrane into spider-like geometries. The incident radiation is absorbed by crossed dipoles made from gold-palladium alloy with a surface resistance of 10 Ω/. Using the COSMOS finite element analysis package, the thermal conductance is obtained for the bolometers of different geometries. FEA simulations showed that the deposition of a gold ring around the absorbing area could increase the sensitivity of the bolometer. Therefore, a gold ring is deposited around the center absorbing patch of the silicon nitride membrane. For the bolometer with a gold ring, the measured NEP is 1.7 × 10-16W/√ Hz and the time constant is in the range between 1.4 and 2 ms.

The ASTRI SST-2M telescope prototype for the Cherenkov Telescope Array: camera DAQ software architecture

NASA Astrophysics Data System (ADS)

Conforti, Vito; Trifoglio, Massimo; Bulgarelli, Andrea; Gianotti, Fulvio; Fioretti, Valentina; Tacchini, Alessandro; Zoli, Andrea; Malaguti, Giuseppe; Capalbi, Milvia; Catalano, Osvaldo

2014-07-01

ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) is a Flagship Project financed by the Italian Ministry of Education, University and Research, and led by INAF, the Italian National Institute of Astrophysics. Within this framework, INAF is currently developing an end-to-end prototype of a Small Size dual-mirror Telescope. In a second phase the ASTRI project foresees the installation of the first elements of the array at CTA southern site, a mini-array of 7 telescopes. The ASTRI Camera DAQ Software is aimed at the Camera data acquisition, storage and display during Camera development as well as during commissioning and operations on the ASTRI SST-2M telescope prototype that will operate at the INAF observing station located at Serra La Nave on the Mount Etna (Sicily). The Camera DAQ configuration and operations will be sequenced either through local operator commands or through remote commands received from the Instrument Controller System that commands and controls the Camera. The Camera DAQ software will acquire data packets through a direct one-way socket connection with the Camera Back End Electronics. In near real time, the data will be stored in both raw and FITS format. The DAQ Quick Look component will allow the operator to display in near real time the Camera data packets. We are developing the DAQ software adopting the iterative and incremental model in order to maximize the software reuse and to implement a system which is easily adaptable to changes. This contribution presents the Camera DAQ Software architecture with particular emphasis on its potential reuse for the ASTRI/CTA mini-array.

Concept design of an 80-dual polarization element cryogenic phased array camera for the Arecibo Radio Telescope

NASA Astrophysics Data System (ADS)

Cortes-Medellin, German; Parshley, Stephen; Campbell, Donald B.; Warnick, Karl F.; Jeffs, Brian D.; Ganesh, Rajagopalan

2016-08-01

This paper presents the current concept design for ALPACA (Advanced L-Band Phased Array Camera for Arecibo) an L-Band cryo-phased array instrument proposed for the 305 m radio telescope of Arecibo. It includes the cryogenically cooled front-end with 160 low noise amplifiers, a RF-over-fiber signal transport and a digital beam former with an instantaneous bandwidth of 312.5 MHz per channel. The camera will digitally form 40 simultaneous beams inside the available field of view of the Arecibo telescope optics, with an expected system temperature goal of 30 K.

Results from the CUORE-0 experiment

DOE PAGES

Canonica, L.; Alduino, C.; Alfonso, K.; ...

2016-06-09

The CUORE-0 experiment searched for neutrinoless double beta decay in 130 Te using an array of 52 tellurium dioxide crystals, operated as bolometers at a temperature of 10 mK. It took data in the Gran Sasso National Laboratory (Italy) since March 2013 to March 2015. We present the results of a search for neutrinoless double beta decay in 9.8 kg-years 130 Te exposure that allowed us to set the most stringent limit to date on this half-life. The performance of the detector in terms of background and energy resolution is also reported.

Patch antenna terahertz photodetectors

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

Palaferri, D.; Todorov, Y., E-mail: yanko.todorov@univ-paris-diderot.fr; Chen, Y. N.

2015-04-20

We report on the implementation of 5 THz quantum well photodetector exploiting a patch antenna cavity array. The benefit of our plasmonic architecture on the detector performance is assessed by comparing it with detectors made using the same quantum well absorbing region, but processed into a standard 45° polished facet mesa. Our results demonstrate a clear improvement in responsivity, polarization insensitivity, and background limited performance. Peak detectivities in excess of 5 × 10{sup 12} cmHz{sup 1/2}/W have been obtained, a value comparable with that of the best cryogenic cooled bolometers.

Automated Reduction and Calibration of SCUBA Archive Data Using ORAC-DR

NASA Astrophysics Data System (ADS)

Jenness, T.; Stevens, J. A.; Archibald, E. N.; Economou, F.; Jessop, N.; Robson, E. I.; Tilanus, R. P. J.; Holland, W. S.

The Submillimetre Common User Bolometer Array (SCUBA) instrument has been operating on the James Clerk Maxwell Telescope (JCMT) since 1997. The data archive is now sufficiently large that it can be used for investigating instrumental properties and the variability of astronomical sources. This paper describes the automated calibration and reduction scheme used to process the archive data with particular emphasis on the pointing observations. This is made possible by using the ORAC-DR data reduction pipeline, a flexible and extensible data reduction pipeline that is used on UKIRT and the JCMT.

Advanced ACTPol Multichroic Polarimeter Array Fabrication Process for 150 mm Wafers

NASA Astrophysics Data System (ADS)

Duff, S. M.; Austermann, J.; Beall, J. A.; Becker, D.; Datta, R.; Gallardo, P. A.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.; Koopman, B. J.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Pappas, C. G.; Salatino, M.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Van Lanen, J.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

2016-08-01

Advanced ACTPol (AdvACT) is a third-generation cosmic microwave background receiver to be deployed in 2016 on the Atacama Cosmology Telescope (ACT). Spanning five frequency bands from 25 to 280 GHz and having just over 5600 transition-edge sensor (TES) bolometers, this receiver will exhibit increased sensitivity and mapping speed compared to previously fielded ACT instruments. This paper presents the fabrication processes developed by NIST to scale to large arrays of feedhorn-coupled multichroic AlMn-based TES polarimeters on 150-mm diameter wafers. In addition to describing the streamlined fabrication process which enables high yields of densely packed detectors across larger wafers, we report the details of process improvements for sensor (AlMn) and insulator (SiN_x) materials and microwave structures, and the resulting performance improvements.

Fabrication of Antenna-Coupled KID Array for Cosmic Microwave Background Detection

NASA Astrophysics Data System (ADS)

Tang, Q. Y.; Barry, P. S.; Basu Thakur, R.; Kofman, A.; Nadolski, A.; Vieira, J.; Shirokoff, E.

2018-05-01

Kinetic inductance detectors (KIDs) have become an attractive alternative to traditional bolometers in the sub-mm and mm observing community due to their innate frequency multiplexing capabilities and simple lithographic processes. These advantages make KIDs a viable option for the O(500,000) detectors needed for the upcoming Cosmic Microwave Background-Stage 4 experiment. We have fabricated an antenna-coupled MKID array in the 150 GHz band optimized for CMB detection. Our design uses a twin-slot antenna coupled to an inverted microstrip made from a superconducting Nb/Al bilayer as the strip, a Nb ground plane and a SiN_x dielectric layer in between, which is then coupled to an Al KID grown on high-resistivity Si. We present the fabrication process and measurements of SiN_x microstrip resonators.

Advanced ACTPol Multichroic Polarimeter Array Fabrication Process for 150 mm Wafers

NASA Technical Reports Server (NTRS)

Duff, S. M.; Austermann, J.; Beall, J. A.; Becker, D.; Datta, R.; Gallardo, P. A.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.;

Multi-focused microlens array optimization and light field imaging study based on Monte Carlo method.

PubMed

Li, Tian-Jiao; Li, Sai; Yuan, Yuan; Liu, Yu-Dong; Xu, Chuan-Long; Shuai, Yong; Tan, He-Ping

2017-04-03

Plenoptic cameras are used for capturing flames in studies of high-temperature phenomena. However, simulations of plenoptic camera models can be used prior to the experiment improve experimental efficiency and reduce cost. In this work, microlens arrays, which are based on the established light field camera model, are optimized into a hexagonal structure with three types of microlenses. With this improved plenoptic camera model, light field imaging of static objects and flame are simulated using the calibrated parameters of the Raytrix camera (R29). The optimized models improve the image resolution, imaging screen utilization, and shooting range of depth of field.

Active hyperspectral imaging using a quantum cascade laser (QCL) array and digital-pixel focal plane array (DFPA) camera.

PubMed

Goyal, Anish; Myers, Travis; Wang, Christine A; Kelly, Michael; Tyrrell, Brian; Gokden, B; Sanchez, Antonio; Turner, George; Capasso, Federico

2014-06-16

We demonstrate active hyperspectral imaging using a quantum-cascade laser (QCL) array as the illumination source and a digital-pixel focal-plane-array (DFPA) camera as the receiver. The multi-wavelength QCL array used in this work comprises 15 individually addressable QCLs in which the beams from all lasers are spatially overlapped using wavelength beam combining (WBC). The DFPA camera was configured to integrate the laser light reflected from the sample and to perform on-chip subtraction of the passive thermal background. A 27-frame hyperspectral image was acquired of a liquid contaminant on a diffuse gold surface at a range of 5 meters. The measured spectral reflectance closely matches the calculated reflectance. Furthermore, the high-speed capabilities of the system were demonstrated by capturing differential reflectance images of sand and KClO₃ particles that were moving at speeds of up to 10 m/s.

Initial astronomical results with a new 5-14 micron Si:Ga 58x62 DRO array camera

NASA Technical Reports Server (NTRS)

Gezari, Dan; Folz, Walter; Woods, Larry

1989-01-01

A new array camera system was developed using a 58 x 62 pixel Si:Ga (gallium doped silicon) DRO (direct readout) photoconductor array detector manufactured by Hughes/Santa Barbara Research Center (SBRC). The camera system is a broad band photometer designed for 5 to 14 micron imaging with large ground-based optical telescopes. In a typical application a 10 micron photon flux of about 10(exp 9) photons sec(exp -1) m(exp -2) microns(exp -1) arcsec(exp -2) is incident in the telescope focal plane, while the detector well capacity of these arrays is 10(exp 5) to 10 (exp 6) electrons. However, when the real efficiencies and operating conditions are accounted for, the 2-channel 3596 pixel array operates with about 1/2 full wells at 10 micron and 10% bandwidth with high duty cycle and no real experimental compromises.

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This medium close-up view of one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. This view shows the cell side of the minus V-2 panel. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Characterization of AlMn TES Impedance, Noise, and Optical Efficiency in the First 150 mm Multichroic Array for Advanced ACTPol

NASA Technical Reports Server (NTRS)

Crowley, Kevin T.; Choi, Steve K.; Kuan, Jeffrey; Austermann, Jason E.; Beall, James A.; Datta, Rahul; Duff, Shannon M.; Gallardo, Patricia A.; Hasselfield, Matthew; Henderson, Shawn W.;

Gamma ray camera

DOEpatents

Perez-Mendez, V.

1997-01-21

A gamma ray camera is disclosed for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array. 6 figs.

Gamma ray camera

DOEpatents

Perez-Mendez, Victor

1997-01-01

A gamma ray camera for detecting rays emanating from a radiation source such as an isotope. The gamma ray camera includes a sensor array formed of a visible light crystal for converting incident gamma rays to a plurality of corresponding visible light photons, and a photosensor array responsive to the visible light photons in order to form an electronic image of the radiation therefrom. The photosensor array is adapted to record an integrated amount of charge proportional to the incident gamma rays closest to it, and includes a transparent metallic layer, photodiode consisting of a p-i-n structure formed on one side of the transparent metallic layer, and comprising an upper p-type layer, an intermediate layer and a lower n-type layer. In the preferred mode, the scintillator crystal is composed essentially of a cesium iodide (CsI) crystal preferably doped with a predetermined amount impurity, and the p-type upper intermediate layers and said n-type layer are essentially composed of hydrogenated amorphous silicon (a-Si:H). The gamma ray camera further includes a collimator interposed between the radiation source and the sensor array, and a readout circuit formed on one side of the photosensor array.

ARNICA, the NICMOS 3 imaging camera of TIRGO.

NASA Astrophysics Data System (ADS)

Lisi, F.; Baffa, C.; Hunt, L.; Stanga, R.

ARNICA (ARcetri Near Infrared CAmera) is the imaging camera for the near infrared bands between 1.0 and 2.5 μm that Arcetri Observatory has designed and built as a general facility for the TIRGO telescope (1.5 m diameter, f/20) located at Gornergrat (Switzerland). The scale is 1″per pixel, with sky coverage of more than 4 min×4 min on the NICMOS 3 (256×256 pixels, 40 μm side) detector array. The camera is remotely controlled by a PC 486, connected to the array control electronics via a fiber-optics link. A C-language package, running under MS-DOS on the PC 486, acquires and stores the frames, and controls the timing of the array. The camera is intended for imaging of large extra-galactic and Galactic fields; a large effort has been dedicated to explore the possibility of achieving precise photometric measurements in the J, H, K astronomical bands, with very promising results.

A front-end electronic system for large arrays of bolometers

NASA Astrophysics Data System (ADS)

Arnaboldi, C.; Carniti, P.; Cassina, L.; Gotti, C.; Liu, X.; Maino, M.; Pessina, G.; Rosenfeld, C.; Zhu, B. X.

2018-02-01

CUORE is an array of thermal calorimeters composed of 988 crystals held at about 10 mK, whose absorbed energy is read out with semiconductor thermistors. The composition of the crystal is TeO2, and the aim is the study of the double beta decay of 130Te on very long and stable runs. CUPID-0 is an array of 26 Zn82Se crystals with double thermistor readout to study the double beta decay of 82Se. In the present paper, we present an overview of the entire front-end electronic readout chain, from the preamplifier to the anti-aliasing filter. This overview includes motivations, design strategies, circuit implementation and performance results of the electronic system, including other auxiliary yet important elements like power supplies and the slow control communication system. The stringent requirements of stability on the very long experimental runs that are foreseen during CUORE and CUPID-0 operation, are achieved thanks to novel solutions of the front-end preamplifier and of the detector bias circuit setup.

Enhancements to a Superconducting Quantum Interference Device (SQUID) Multiplexer Readout and Control System

NASA Technical Reports Server (NTRS)

Forgione, J.; Benford, D. J.; Buchanan, E. D.; Moseley, S. H.; Rebar, J.; Shafer, R. A.

2004-01-01

Far-infrared detector arrays such as the 16x32 superconducting bolometer array for the SAFIRE instrument (flying on the SOFIA airborne observatory) require systems of readout and control electronics to provide translation between a user-driven, digital PC and the cold, analog world of the cryogenic detector. In 2001, the National Institute of Standards and Technology (NIST) developed their Mark III electronics for purposes of control and readout of their 1x32 SQUID Multiplexer chips. We at NASA s Goddard Space Flight Center acquired a Mark 111 system and subsequently designed upgrades to suit our and our collaborators purposes. We developed an arbitrary, programmable multiplexing system that allows the user to cycle through rows in a SQUID array in an infinite number of combinations. We provided hooks in the Mark III system to allow readout of signals from outside the Mark 111 system, such as telescope status information. Finally, we augmented the heart of the system with a new feedback algorithm implementation, flexible diagnostic tools, and informative telemetry.

Enhancements to a superconducting quantum interference device (SQUID) multiplexer readout and control system

NASA Astrophysics Data System (ADS)

Forgione, Joshua B.; Benford, Dominic J.; Buchanan, Ernest D.; Moseley, S. H., Jr.; Rebar, Joyce; Shafer, Richard A.

2004-10-01

Far-infrared detector arrays such as the 16x32 superconducting bolometer array for the SAFIRE instrument (flying on the SOFIA airborne observatory) require systems of readout and control electronics to provide translation between a user-driven, digital PC and the cold, analog world of the cryogenic detector. In 2001, the National Institute of Standards and Technology (NIST) developed their Mark III electronics for purposes of control and readout of their 1x32 SQUID Multiplexer chips. We at NASA's Goddard Space Flight Center acquired a Mark III system and subsequently designed upgrades to suit our and our collaborators' purposes. We developed an arbitrary, programmable multiplexing system that allows the user to cycle through rows in a SQUID array in an infinite number of combinations. We provided 'hooks' in the Mark III system to allow readout of signals from outside the Mark III system, such as telescope status information. Finally, we augmented the heart of the system with a new feedback algorithm implementation, flexible diagnostic tools, and informative telemetry.

The Detection and Photometric Redshift Determination of Distant Galaxies using SIRTF's Infrared Array Camera

NASA Technical Reports Server (NTRS)

Simpson, C.; Eisenhardt, P.

1998-01-01

We investigate the ability of the Space Infrared Telescope Facility's Infrared Array Camera to detect distant (z3) galaxies and measure their photometric redshifts. Our analysis shows that changing the original long wavelength filter specifications provides significant improvements in performance in this and other areas.

First Results from BISTRO: A SCUBA-2 Polarimeter Survey of the Gould Belt

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

Ward-Thompson, Derek; Pattle, Kate; Kirk, Jason M.

We present the first results from the B-fields In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope in Hawaii. We discuss the survey’s aims and objectives. We describe the rationale behind the survey, and the questions that the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability andmore » consistency with previous data. We present a first-look analysis of the first results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous “integral filament” in the densest regions of that filament. Furthermore, we see an “hourglass” magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density northeastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments.« less

First Results from BISTRO: A SCUBA-2 Polarimeter Survey of the Gould Belt

NASA Astrophysics Data System (ADS)

Ward-Thompson, Derek; Pattle, Kate; Bastien, Pierre; Furuya, Ray S.; Kwon, Woojin; Lai, Shih-Ping; Qiu, Keping; Berry, David; Choi, Minho; Coudé, Simon; Di Francesco, James; Hoang, Thiem; Franzmann, Erica; Friberg, Per; Graves, Sarah F.; Greaves, Jane S.; Houde, Martin; Johnstone, Doug; Kirk, Jason M.; Koch, Patrick M.; Kwon, Jungmi; Lee, Chang Won; Li, Di; Matthews, Brenda C.; Mottram, Joseph C.; Parsons, Harriet; Pon, Andy; Rao, Ramprasad; Rawlings, Mark; Shinnaga, Hiroko; Sadavoy, Sarah; van Loo, Sven; Aso, Yusuke; Byun, Do-Young; Eswaraiah, Chakali; Chen, Huei-Ru; Chen, Mike C.-Y.; Chen, Wen Ping; Ching, Tao-Chung; Cho, Jungyeon; Chrysostomou, Antonio; Chung, Eun Jung; Doi, Yasuo; Drabek-Maunder, Emily; Eyres, Stewart P. S.; Fiege, Jason; Friesen, Rachel K.; Fuller, Gary; Gledhill, Tim; Griffin, Matt J.; Gu, Qilao; Hasegawa, Tetsuo; Hatchell, Jennifer; Hayashi, Saeko S.; Holland, Wayne; Inoue, Tsuyoshi; Inutsuka, Shu-ichiro; Iwasaki, Kazunari; Jeong, Il-Gyo; Kang, Ji-hyun; Kang, Miju; Kang, Sung-ju; Kawabata, Koji S.; Kemper, Francisca; Kim, Gwanjeong; Kim, Jongsoo; Kim, Kee-Tae; Kim, Kyoung Hee; Kim, Mi-Ryang; Kim, Shinyoung; Lacaille, Kevin M.; Lee, Jeong-Eun; Lee, Sang-Sung; Li, Dalei; Li, Hua-bai; Liu, Hong-Li; Liu, Junhao; Liu, Sheng-Yuan; Liu, Tie; Lyo, A.-Ran; Mairs, Steve; Matsumura, Masafumi; Moriarty-Schieven, Gerald H.; Nakamura, Fumitaka; Nakanishi, Hiroyuki; Ohashi, Nagayoshi; Onaka, Takashi; Peretto, Nicolas; Pyo, Tae-Soo; Qian, Lei; Retter, Brendan; Richer, John; Rigby, Andrew; Robitaille, Jean-François; Savini, Giorgio; Scaife, Anna M. M.; Soam, Archana; Tamura, Motohide; Tang, Ya-Wen; Tomisaka, Kohji; Wang, Hongchi; Wang, Jia-Wei; Whitworth, Anthony P.; Yen, Hsi-Wei; Yoo, Hyunju; Yuan, Jinghua; Zhang, Chuan-Peng; Zhang, Guoyin; Zhou, Jianjun; Zhu, Lei; André, Philippe; Dowell, C. Darren; Falle, Sam; Tsukamoto, Yusuke

2017-06-01

We present the first results from the B-fields In STar-forming Region Observations (BISTRO) survey, using the Sub-millimetre Common-User Bolometer Array 2 camera, with its associated polarimeter (POL-2), on the James Clerk Maxwell Telescope in Hawaii. We discuss the survey’s aims and objectives. We describe the rationale behind the survey, and the questions that the survey will aim to answer. The most important of these is the role of magnetic fields in the star formation process on the scale of individual filaments and cores in dense regions. We describe the data acquisition and reduction processes for POL-2, demonstrating both repeatability and consistency with previous data. We present a first-look analysis of the first results from the BISTRO survey in the OMC 1 region. We see that the magnetic field lies approximately perpendicular to the famous “integral filament” in the densest regions of that filament. Furthermore, we see an “hourglass” magnetic field morphology extending beyond the densest region of the integral filament into the less-dense surrounding material, and discuss possible causes for this. We also discuss the more complex morphology seen along the Orion Bar region. We examine the morphology of the field along the lower-density northeastern filament. We find consistency with previous theoretical models that predict magnetic fields lying parallel to low-density, non-self-gravitating filaments, and perpendicular to higher-density, self-gravitating filaments.

The upgrade of the H.E.S.S. cameras

NASA Astrophysics Data System (ADS)

Giavitto, Gianluca; Ashton, Terry; Balzer, Arnim; Berge, David; Brun, Francois; Chaminade, Thomas; Delagnes, Eric; Fontaine, Gerard; Füßling, Matthias; Giebels, Berrie; Glicenstein, Jean-Francois; Gräber, Tobias; Hinton, Jim; Jahnke, Albert; Klepser, Stefan; Kossatz, Marko; Kretzschmann, Axel; Lefranc, Valentin; Leich, Holger; Lüdecke, Hartmut; Lypova, Iryna; Manigot, Pascal; Marandon, Vincent; Moulin, Emmanuel; Naurois, Mathieu de; Nayman, Patrick; Ohm, Stefan; Penno, Marek; Ross, Duncan; Salek, David; Schade, Markus; Schwab, Thomas; Simoni, Rachel; Stegmann, Christian; Steppa, Constantin; Thornhill, Julian; Toussnel, Francois

2017-12-01

The High Energy Stereoscopic System (HESS) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in the Khomas highland in Namibia. It was built to detect Very High Energy (VHE > 100 GeV) cosmic gamma rays. Since 2003, HESS has discovered the majority of the known astrophysical VHE gamma-ray sources, opening a new observational window on the extreme non-thermal processes at work in our universe. HESS consists of four 12-m diameter Cherenkov telescopes (CT1-4), which started data taking in 2002, and a larger 28-m telescope (CT5), built in 2012, which lowers the energy threshold of the array to 30 GeV . The cameras of CT1-4 are currently undergoing an extensive upgrade, with the goals of reducing their failure rate, reducing their readout dead time and improving the overall performance of the array. The entire camera electronics has been renewed from ground-up, as well as the power, ventilation and pneumatics systems, and the control and data acquisition software. Only the PMTs and their HV supplies have been kept from the original cameras. Novel technical solutions have been introduced, which will find their way into some of the Cherenkov cameras foreseen for the next-generation Cherenkov Telescope Array (CTA) observatory. In particular, the camera readout system is the first large-scale system based on the analog memory chip NECTAr, which was designed for CTA cameras. The camera control subsystems and the control software framework also pursue an innovative design, exploiting cutting-edge hardware and software solutions which excel in performance, robustness and flexibility. The CT1 camera has been upgraded in July 2015 and is currently taking data; CT2-4 have been upgraded in fall 2016. Together they will assure continuous operation of HESS at its full sensitivity until and possibly beyond the advent of CTA. This contribution describes the design, the testing and the in-lab and on-site performance of all components of the newly upgraded HESS camera.

Characterization of Kilopixel TES detector arrays for PIPER

NASA Astrophysics Data System (ADS)

Datta, Rahul; Ade, Peter; Benford, Dominic; Bennett, Charles; Chuss, David; Costen, Nicholas; Coughlin, Kevin; Dotson, Jessie; Eimer, Joseph; Fixsen, Dale; Gandilo, Natalie; Halpern, Mark; Essinger-Hileman, Thomas; Hilton, Gene; Hinshaw, Gary; Irwin, Kent; Jhabvala, Christine; Kimball, Mark; Kogut, Al; Lazear, Justin; Lowe, Luke; Manos, George; McMahon, Jeff; Miller, Timothy; Mirel, Paul; Moseley, Samuel Harvey; Pawlyk, Samuel; Rodriguez, Samelys; Sharp, Elmer; Shirron, Peter; Staguhn, Johannes G.; Sullivan, Dan; Switzer, Eric; Taraschi, Peter; Tucker, Carole; Walts, Alexander; Wollack, Edward

2018-01-01

The Primordial Inflation Polarization ExploreR (PIPER) is a balloon-borne instrument optimized to measure the polarization of the Cosmic Microwave Background (CMB) at large angular scales. It will map 85% of the sky in four frequency bands centered at 200, 270, 350, and 600 GHz to characterize dust foregrounds and constrain the tensor-to-scalar ratio, r. The sky is imaged on to 32x40 pixel arrays of time-domain multiplexed Transition-Edge Sensor (TES) bolometers operating at a bath temperature of 100 mK to achieve background-limited sensitivity. Each kilopixel array is indium-bump-bonded to a 2D superconducting quantum interference device (SQUID) time-domain multiplexer (MUX) chip and read out by warm electronics. Each pixel measures total incident power over a frequency band defined by bandpass filters in front of the array, while polarization sensitivity is provided by the upstream Variable-delay Polarization Modulators (VPMs) and analyzer grids. We present measurements of the detector parameters from the laboratory characterization of the first kilopixel science array for PIPER including transition temperature, saturation power, thermal conductivity, time constant, and noise performance. We also describe the testing of the 2D MUX chips, optimization of the integrated readout parameters, and the overall pixel yield of the array. The first PIPER science flight is planned for June 2018 from Palestine, Texas.

bicep2/KECK ARRAY. IV. OPTICAL CHARACTERIZATION AND PERFORMANCE OF THE bicep2 AND KECK ARRAY EXPERIMENTS

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

Ade, P. A. R.; Aikin, R. W.; Bock, J. J.

2015-06-20

bicep2 and the Keck Array are polarization-sensitive microwave telescopes that observe the cosmic microwave background (CMB) from the South Pole at degree angular scales in search of a signature of inflation imprinted as B-mode polarization in the CMB. bicep2 was deployed in late 2009, observed for three years until the end of 2012 at 150 GHz with 512 antenna-coupled transition edge sensor bolometers, and has reported a detection of B-mode polarization on degree angular scales. The Keck Array was first deployed in late 2010 and will observe through 2016 with five receivers at several frequencies (95, 150, and 220 GHz). bicep2 and the Keck Array sharemore » a common optical design and employ the field-proven bicep1 strategy of using small-aperture, cold, on-axis refractive optics, providing excellent control of systematics while maintaining a large field of view. This design allows for full characterization of far-field optical performance using microwave sources on the ground. Here we describe the optical design of both instruments and report a full characterization of the optical performance and beams of bicep2 and the Keck Array at 150 GHz.« less

Fabrication of Detector Arrays for the SPT-3G Receiver

NASA Astrophysics Data System (ADS)

Posada, C. M.; Ade, P. A. R.; Ahmed, Z.; Anderson, A. J.; Austermann, J. E.; Avva, J. S.; Thakur, R. Basu; Bender, A. N.; Benson, B. A.; Carlstrom, J. E.; Carter, F. W.; Cecil, T.; Chang, C. L.; Cliche, J. F.; Cukierman, A.; Denison, E. V.; de Haan, T.; Ding, J.; Divan, R.; Dobbs, M. A.; Dutcher, D.; Everett, W.; Foster, A.; Gannon, R. N.; Gilbert, A.; Groh, J. C.; Halverson, N. W.; Harke-Hosemann, A. H.; Harrington, N. L.; Henning, J. W.; Hilton, G. C.; Holzapfel, W. L.; Huang, N.; Irwin, K. D.; Jeong, O. B.; Jonas, M.; Khaire, T.; Kofman, A. M.; Korman, M.; Kubik, D.; Kuhlmann, S.; Kuo, C. L.; Lee, A. T.; Lowitz, A. E.; Meyer, S. S.; Michalik, D.; Miller, C. S.; Montgomery, J.; Nadolski, A.; Natoli, T.; Nguyen, H.; Noble, G. I.; Novosad, V.; Padin, S.; Pan, Z.; Pearson, J.; Rahlin, A.; Ruhl, J. E.; Saunders, L. J.; Sayre, J. T.; Shirley, I.; Shirokoff, E.; Smecher, G.; Sobrin, J. A.; Stan, L.; Stark, A. A.; Story, K. T.; Suzuki, A.; Tang, Q. Y.; Thompson, K. L.; Tucker, C.; Vale, L. R.; Vanderlinde, K.; Vieira, J. D.; Wang, G.; Whitehorn, N.; Yefremenko, V.; Yoon, K. W.; Young, M. R.

2018-05-01

The South Pole Telescope third-generation (SPT-3G) receiver was installed during the austral summer of 2016-2017. It is designed to measure the cosmic microwave background across three frequency bands centered at 95, 150, and 220 GHz. The SPT-3G receiver has ten focal plane modules, each with 269 pixels. Each pixel features a broadband sinuous antenna coupled to a niobium microstrip transmission line. In-line filters define the desired band-passes before the signal is coupled to six bolometers with Ti/Au/Ti/Au transition edge sensors (three bands × two polarizations). In total, the SPT-3G receiver is composed of 16,000 detectors, which are read out using a 68× frequency-domain multiplexing scheme. In this paper, we present the process employed in fabricating the detector arrays.

THz holography in reflection using a high resolution microbolometer array.

PubMed

Zolliker, Peter; Hack, Erwin

2015-05-04

We demonstrate a digital holographic setup for Terahertz imaging of surfaces in reflection. The set-up is based on a high-power continuous wave (CW) THz laser and a high-resolution (640 × 480 pixel) bolometer detector array. Wave propagation to non-parallel planes is used to reconstruct the object surface that is rotated relative to the detector plane. In addition we implement synthetic aperture methods for resolution enhancement and compare Fourier transform phase retrieval to phase stepping methods. A lateral resolution of 200 μm and a relative phase sensitivity of about 0.4 rad corresponding to a depth resolution of 6 μm are estimated from reconstructed images of two specially prepared test targets, respectively. We highlight the use of digital THz holography for surface profilometry as well as its potential for video-rate imaging.

Selenium immersed thermistor bolometer study

NASA Technical Reports Server (NTRS)

Rolls, W. H.

1979-01-01

The noise characteristics of thermistor bolometers immersed in layers of arsenic/selenium glass uniform in composition were examined. Using a controlled deposition technique, layers of glass were deposited, thermistor bolometers immersed, and their electrical characteristics measured after various thermal treatments. Markedly improved stability of the detector noise was observed using this new technique.

A progress report on bolometers operating at 0.1 K using adiabatic demagnetization refrigeration

NASA Technical Reports Server (NTRS)

Roellig, T.; Lesyna, L.; Werner, M.; Kittel, P.

1986-01-01

Bolometers are still the detectors of choice for low background infrared observations at wavelengths longer than 200 microns. In the low background limit, bolometers become more sensitive as their operating temperature decreases, due to fundamental thermodynamic laws. The adiabatic demagnetization technique was evaluated by building a bolometer detection system operating at a wavelength of 1 millimeter for use at a ground based telescope. The system was fit checked at the telescope and is expected to take its first data in November, 1985.

Experience with the UKIRT InSb array camera

NASA Technical Reports Server (NTRS)

Mclean, Ian S.; Casali, Mark M.; Wright, Gillian S.; Aspin, Colin

1989-01-01

The cryogenic infrared camera, IRCAM, has been operating routinely on the 3.8 m UK Infrared Telescope on Mauna Kea, Hawaii for over two years. The camera, which uses a 62x58 element Indium Antimonide array from Santa Barbara Research Center, was designed and built at the Royal Observatory, Edinburgh which operates UKIRT on behalf of the UK Science and Engineering Research Council. Over the past two years at least 60% of the available time on UKIRT has been allocated for IRCAM observations. Described here are some of the properties of this instrument and its detector which influence astronomical performance. Observational techniques and the power of IR arrays with some recent astronomical results are discussed.

A dual-polarized broadband planar antenna and channelizing filter bank for millimeter wavelengths

NASA Astrophysics Data System (ADS)

O'Brient, Roger; Ade, Peter; Arnold, Kam; Edwards, Jennifer; Engargiola, Greg; Holzapfel, William L.; Lee, Adrian T.; Myers, Michael J.; Quealy, Erin; Rebeiz, Gabriel; Richards, Paul; Suzuki, Aritoki

2013-02-01

We describe the design, fabrication, and testing of a broadband log-periodic antenna coupled to multiple cryogenic bolometers. This detector architecture, optimized here for astrophysical observations, simultaneously receives two linear polarizations with two octaves of bandwidth at millimeter wavelengths. The broad bandwidth signal received by the antenna is divided into sub-bands with integrated in-line frequency-selective filters. We demonstrate two such filter banks: a diplexer with two sub-bands and a log-periodic channelizer with seven contiguous sub-bands. These detectors have receiver efficiencies of 20%-40% and percent level polarization isolation. Superconducting transition-edge sensor bolometers detect the power in each sub-band and polarization. We demonstrate circularly symmetric beam patterns, high polarization isolation, accurately positioned bands, and high optical efficiency. The pixel design is applicable to astronomical observations of intensity and polarization at millimeter through sub-millimeter wavelengths. As compared with an imaging array of pixels measuring only one band, simultaneous measurements of multiple bands in each pixel has the potential to result in a higher signal-to-noise measurement while also providing spectral information. This development facilitates compact systems with high mapping speeds for observations that require information in multiple frequency bands.

A Major Upgrade of the H.E.S.S. Cherenkov Cameras

NASA Astrophysics Data System (ADS)

Lypova, Iryna; Giavitto, Gianluca; Ashton, Terry; Balzer, Arnim; Berge, David; Brun, Francois; Chaminade, Thomas; Delagnes, Eric; Fontaine, Gerard; Füßling, Matthias; Giebels, Berrie; Glicenstein, Jean-Francois; Gräber, Tobias; Hinton, Jim; Jahnke, Albert; Klepser, Stefan; Kossatz, Marko; Kretzschmann, Axel; Lefranc, Valentin; Leich, Holger; Lüdecke, Hartmut; Manigot, Pascal; Marandon, Vincent; Moulin, Emmanuel; de Naurois, Mathieu; Nayman, Patrick; Ohm, Stefan; Penno, Marek; Ross, Duncan; Salek, David; Schade, Markus; Schwab, Thomas; Simoni, Rachel; Stegmann, Christian; Steppa, Constantin; Thornhill, Julian; Toussnel, Francois

2017-03-01

The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in Namibia. It was built to detect Very High Energy (VHE, >100 GeV) cosmic gamma rays, and consists of four 12 m diameter Cherenkov telescopes (CT1-4), built in 2003, and a larger 28 m telescope (CT5), built in 2012. The larger mirror surface of CT5 permits to lower the energy threshold of the array down to 30 GeV. The cameras of CT1-4 are currently undergoing an extensive upgrade, with the goals of reducing their failure rate, reducing their readout dead time and improving the overall performance of the array. The entire camera electronics has been renewed from ground-up, as well as the power, ventilation and pneumatics systems, and the control and data acquisition software. Technical solutions forseen for the next-generation Cherenkov Telescope Array (CTA) observatory have been introduced, most notably the readout is based on the NECTAr analog memory chip. The camera control subsystems and the control software framework also pursue an innovative design, increasing the camera performance, robustness and flexibility. The CT1 camera has been upgraded in July 2015 and is currently taking data; CT2-4 will upgraded in Fall 2016. Together they will assure continuous operation of H.E.S.S at its full sensitivity until and possibly beyond the advent of CTA. This contribution describes the design, the testing and the in-lab and on-site performance of all components of the newly upgraded H.E.S.S. camera.

An astronomy camera for low background applications in the 1. 0 to 2. 5. mu. m spectral region

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

Kaki, S.A.; Bailey, G.C.; Hagood, R.W.

1989-02-01

A short wavelength (1.0-2.5 ..mu..m) 128 x 128 focal plane array forms the heart of this low background astronomy camera system. The camera is designed to accept either a 128 x 128 HgCdTe array for the 1-2.5 ..mu..m spectral region or an InSb array for the 3-5 ..mu..m spectral region. A cryogenic folded optical system is utilized to control excess stray light along with a cold eight-position filter wheel for spectral filtering. The camera head and electronics will also accept a 256 x 256 focal plane. Engineering evaluation of the complete system is complete along with two engineering runs atmore » the JPL Table Mountain Observatory. System design, engineering performance, and sample imagery are presented in this paper.« less

The multifocus plenoptic camera

NASA Astrophysics Data System (ADS)

Georgiev, Todor; Lumsdaine, Andrew

2012-01-01

The focused plenoptic camera is based on the Lippmann sensor: an array of microlenses focused on the pixels of a conventional image sensor. This device samples the radiance, or plenoptic function, as an array of cameras with large depth of field, focused at a certain plane in front of the microlenses. For the purpose of digital refocusing (which is one of the important applications) the depth of field needs to be large, but there are fundamental optical limitations to this. The solution of the above problem is to use and array of interleaved microlenses of different focal lengths, focused at two or more different planes. In this way a focused image can be constructed at any depth of focus, and a really wide range of digital refocusing can be achieved. This paper presents our theory and results of implementing such camera. Real world images are demonstrating the extended capabilities, and limitations are discussed.

An Optical and Sunyaev-Zeldovich Blind Cluster Survey

NASA Astrophysics Data System (ADS)

Gomez, Percy; Romer, A. Kathy; Holzapfel, William; Peterson, Jeffrey; Ruhl, John; Goldstein, Jon; Daub, Mike

2005-08-01

We propose to perform multicolor observations of two deep fields that were observed with the ACBAR bolometer array located at the South Pole. These fields were observed down to a sensitivity of 8 microK/5 arcmin beam at 150 GHz. These observations will be used as control fields for our blind cluster survey which has identified some 30 cluster candidates to date. The goal of the observations is to quantify the number of clusters missed by our SZE survey. This information is important in order to derive constraints on sigma-8 from our SZE blind cluster survey.

Detection of Shock-Heated Gas Using the Sz Effect in Rxj 1347-1145

NASA Technical Reports Server (NTRS)

Mason, Brian S.; Dicker, S.; Korngut, P.; Devlin, M.; Cotton, W.; Koch, P.; Molnar, S.; Aguirre, J.; Benford, D.; Staguhn, J.;

Terahertz holography for imaging amplitude and phase objects.

PubMed

Hack, Erwin; Zolliker, Peter

2014-06-30

A non-monochromatic THz Quantum Cascade Laser and an uncooled micro-bolometer array detector with VGA resolution are used in a beam-splitter free holographic set-up to measure amplitude and phase objects in transmission. Phase maps of the diffraction pattern are retrieved using the Fourier transform carrier fringe method; while a Fresnel-Kirchhoff back propagation algorithm is used to reconstruct the complex object image. A lateral resolution of 280 µm and a relative phase sensitivity of about 0.5 rad are estimated from reconstructed images of a metallic Siemens star and a polypropylene test structure, respectively. Simulations corroborate the experimental results.

CUORE-0 detector: design, construction and operation

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

Alduino, C.; Alfonso, K.; Artusa, D. R.

The CUORE experiment will search for neutrinoless double-beta decay of 130Te with an array of 988 TeO 2 bolometers arranged in 19 towers. CUORE-0, the first tower assembled according to the CUORE procedures, was built and commissioned at Laboratori Nazionali del Gran Sasso, and took data from March 2013 to March 2015. In this study we describe the design, construction and operation of the CUORE-0 experiment, with an emphasis on the improvements made over a predecessor experiment, Cuoricino. Finally, in particular, we demonstrate with CUORE-0 data that the design goals of CUORE are within reach.

CUORE-0 detector: design, construction and operation

DOE PAGES

Alduino, C.; Alfonso, K.; Artusa, D. R.; ...

2016-07-12

The CUORE experiment will search for neutrinoless double-beta decay of 130Te with an array of 988 TeO 2 bolometers arranged in 19 towers. CUORE-0, the first tower assembled according to the CUORE procedures, was built and commissioned at Laboratori Nazionali del Gran Sasso, and took data from March 2013 to March 2015. In this study we describe the design, construction and operation of the CUORE-0 experiment, with an emphasis on the improvements made over a predecessor experiment, Cuoricino. Finally, in particular, we demonstrate with CUORE-0 data that the design goals of CUORE are within reach.

Implanted Silicon Resistor Layers for Efficient Terahertz Absorption

NASA Technical Reports Server (NTRS)

Chervenak, J. A.; Abrahams, J.; Allen, C. A.; Benford, D. J.; Henry, R.; Stevenson, T.; Wollack, E.; Moseley, S. H.

2005-01-01

Broadband absorption structures are an essential component of large format bolometer arrays for imaging GHz and THz radiation. We have measured electrical and optical properties of implanted silicon resistor layers designed to be suitable for these absorbers. Implanted resistors offer a low-film-stress, buried absorber that is robust to longterm aging, temperature, and subsequent metals processing. Such an absorber layer is readily integrated with superconducting integrated circuits and standard micromachining as demonstrated by the SCUBA II array built by ROE/NIST (1). We present a complete characterization of these layers, demonstrating frequency regimes in which different recipes will be suitable for absorbers. Single layer thin film coatings have been demonstrated as effective absorbers at certain wavelengths including semimetal (2,3), thin metal (4), and patterned metal films (5,6). Astronomical instrument examples include the SHARC II instrument is imaging the submillimeter band using passivated Bi semimetal films and the HAWC instrument for SOFIA, which employs ultrathin metal films to span 1-3 THz. Patterned metal films on spiderweb bolometers have also been proposed for broadband detection. In each case, the absorber structure matches the impedance of free space for optimal absorption in the detector configuration (typically 157 Ohms per square for high absorption with a single or 377 Ohms per square in a resonant cavity or quarter wave backshort). Resonant structures with -20% bandwidth coupled to bolometers are also under development; stacks of such structures may take advantage of instruments imaging over a wide band. Each technique may enable effective absorbers in imagers. However, thin films tend to age, degrade or change during further processing, can be difficult to reproduce, and often exhibit an intrinsic granularity that creates complicated frequency dependence at THz frequencies. Thick metal films are more robust but the requirement for patterning can limit their absorption at THz frequencies and their heat capacity can be high. patterned absorber structures that offer low heat capacity, absence of aging, and uniform, predictable behavior at THz frequencies. We have correlated DC electrical and THz optical measurements of a series of implanted layers and studied their frequency dependence of optical absorption from .3 to 10 THz at cryogenic temperatures. We have modeled the optical response to determine the suitability of the implanted silicon resistor as a function of resistance in the range 10 Ohms/sq to 300 Ohms/sq.

640x480 PtSi Stirling-cooled camera system

NASA Astrophysics Data System (ADS)

Villani, Thomas S.; Esposito, Benjamin J.; Davis, Timothy J.; Coyle, Peter J.; Feder, Howard L.; Gilmartin, Harvey R.; Levine, Peter A.; Sauer, Donald J.; Shallcross, Frank V.; Demers, P. L.; Smalser, P. J.; Tower, John R.

1992-09-01

A Stirling cooled 3 - 5 micron camera system has been developed. The camera employs a monolithic 640 X 480 PtSi-MOS focal plane array. The camera system achieves an NEDT equals 0.10 K at 30 Hz frame rate with f/1.5 optics (300 K background). At a spatial frequency of 0.02 cycles/mRAD the vertical and horizontal Minimum Resolvable Temperature are in the range of MRT equals 0.03 K (f/1.5 optics, 300 K background). The MOS focal plane array achieves a resolution of 480 TV lines per picture height independent of background level and position within the frame.

Automatic Calibration of an Airborne Imaging System to an Inertial Navigation Unit

NASA Technical Reports Server (NTRS)

Ansar, Adnan I.; Clouse, Daniel S.; McHenry, Michael C.; Zarzhitsky, Dimitri V.; Pagdett, Curtis W.

2013-01-01

This software automatically calibrates a camera or an imaging array to an inertial navigation system (INS) that is rigidly mounted to the array or imager. In effect, it recovers the coordinate frame transformation between the reference frame of the imager and the reference frame of the INS. This innovation can automatically derive the camera-to-INS alignment using image data only. The assumption is that the camera fixates on an area while the aircraft flies on orbit. The system then, fully automatically, solves for the camera orientation in the INS frame. No manual intervention or ground tie point data is required.

Motion camera based on a custom vision sensor and an FPGA architecture

NASA Astrophysics Data System (ADS)

Arias-Estrada, Miguel

1998-09-01

A digital camera for custom focal plane arrays was developed. The camera allows the test and development of analog or mixed-mode arrays for focal plane processing. The camera is used with a custom sensor for motion detection to implement a motion computation system. The custom focal plane sensor detects moving edges at the pixel level using analog VLSI techniques. The sensor communicates motion events using the event-address protocol associated to a temporal reference. In a second stage, a coprocessing architecture based on a field programmable gate array (FPGA) computes the time-of-travel between adjacent pixels. The FPGA allows rapid prototyping and flexible architecture development. Furthermore, the FPGA interfaces the sensor to a compact PC computer which is used for high level control and data communication to the local network. The camera could be used in applications such as self-guided vehicles, mobile robotics and smart surveillance systems. The programmability of the FPGA allows the exploration of further signal processing like spatial edge detection or image segmentation tasks. The article details the motion algorithm, the sensor architecture, the use of the event- address protocol for velocity vector computation and the FPGA architecture used in the motion camera system.

Automated recognition and tracking of aerosol threat plumes with an IR camera pod

NASA Astrophysics Data System (ADS)

Fauth, Ryan; Powell, Christopher; Gruber, Thomas; Clapp, Dan

2012-06-01

Protection of fixed sites from chemical, biological, or radiological aerosol plume attacks depends on early warning so that there is time to take mitigating actions. Early warning requires continuous, autonomous, and rapid coverage of large surrounding areas; however, this must be done at an affordable cost. Once a potential threat plume is detected though, a different type of sensor (e.g., a more expensive, slower sensor) may be cued for identification purposes, but the problem is to quickly identify all of the potential threats around the fixed site of interest. To address this problem of low cost, persistent, wide area surveillance, an IR camera pod and multi-image stitching and processing algorithms have been developed for automatic recognition and tracking of aerosol plumes. A rugged, modular, static pod design, which accommodates as many as four micro-bolometer IR cameras for 45deg to 180deg of azimuth coverage, is presented. Various OpenCV1 based image-processing algorithms, including stitching of multiple adjacent FOVs, recognition of aerosol plume objects, and the tracking of aerosol plumes, are presented using process block diagrams and sample field test results, including chemical and biological simulant plumes. Methods for dealing with the background removal, brightness equalization between images, and focus quality for optimal plume tracking are also discussed.

Predicting the response of a submillimeter bolometer to cosmic rays.

PubMed

Woodcraft, Adam L; Sudiwala, Rashmi V; Ade, Peter A R; Griffin, Matthew J; Wakui, Elley; Bhatia, Ravinder S; Lange, Andrew E; Bock, James J; Turner, Anthony D; Yun, Minhee H; Beeman, Jeffrey W

2003-09-01

Bolometers designed to detect submillimeter radiation also respond to cosmic, gamma, and x rays. Because detectors cannot be fully shielded from such energy sources, it is necessary to understand the effect of a photon or cosmic-ray particle being absorbed. The resulting signal (known as a glitch) can then be removed from raw data. We present measurements using an Americium-241 gamma radiation source to irradiate a prototype bolometer for the High Frequency Instrument in the Planck Surveyor satellite. Our measurements showed no variation in response depending on where the radiation was absorbed, demonstrating that the bolometer absorber and thermistor thermalize quickly. The bolometer has previously been fully characterized both electrically and optically. We find that using optically measured time constants underestimates the time taken for the detector to recover from a radiation absorption event. However, a full thermal model for the bolometer, with parameters taken from electrical and optical measurements, provides accurate time constants. Slight deviations from the model were seen at high energies; these can be accounted for by use of an extended model.

Predicting the response of a submillimeter bolometer to cosmic rays

NASA Astrophysics Data System (ADS)

Woodcraft, Adam L.; Sudiwala, Rashmi V.; Ade, Peter A. R.; Griffin, Matthew J.; Wakui, Elley; Bhatia, Ravinder S.; Lange, Andrew E.; Bock, James J.; Turner, Anthony D.; Yun, Minhee H.; Beeman, Jeffrey W.

2003-09-01

Bolometers designed to detect submillimeter radiation also respond to cosmic, gamma, and x rays. Because detectors cannot be fully shielded from such energy sources, it is necessary to understand the effect of a photon or cosmic-ray particle being absorbed. The resulting signal (known as a glitch) can then be removed from raw data. We present measurements using an Americium-241 gamma radiation source to irradiate a prototype bolometer for the High Frequency Instrument in the Planck Surveyor satellite. Our measurements showed no variation in response depending on where the radiation was absorbed, demonstrating that the bolometer absorber and thermistor thermalize quickly. The bolometer has previously been fully characterized both electrically and optically. We find that using optically measured time constants underestimates the time taken for the detector to recover from a radiation absorption event. However, a full thermal model for the bolometer, with parameters taken from electrical and optical measurements, provides accurate time constants. Slight deviations from the model were seen at high energies; these can be accounted for by use of an extended model.

Development of plasma bolometers using fiber-optic temperature sensors

NASA Astrophysics Data System (ADS)

Reinke, M. L.; Han, M.; Liu, G.; van Eden, G. G.; Evenblij, R.; Haverdings, M.; Stratton, B. C.

2016-11-01

Measurements of radiated power in magnetically confined plasmas are important for exhaust studies in present experiments and expected to be a critical diagnostic for future fusion reactors. Resistive bolometer sensors have long been utilized in tokamaks and helical devices but suffer from electromagnetic interference (EMI). Results are shown from initial testing of a new bolometer concept based on fiber-optic temperature sensor technology. A small, 80 μm diameter, 200 μm long silicon pillar attached to the end of a single mode fiber-optic cable acts as a Fabry-Pérot cavity when broadband light, λo ˜ 1550 nm, is transmitted along the fiber. Changes in temperature alter the optical path length of the cavity primarily through the thermo-optic effect, resulting in a shift of fringes reflected from the pillar detected using an I-MON 512 OEM spectrometer. While initially designed for use in liquids, this sensor has ideal properties for use as a plasma bolometer: a time constant, in air, of ˜150 ms, strong absorption in the spectral range of plasma emission, immunity to local EMI, and the ability to measure changes in temperature remotely. Its compact design offers unique opportunities for integration into the vacuum environment in places unsuitable for a resistive bolometer. Using a variable focus 5 mW, 405 nm, modulating laser, the signal to noise ratio versus power density of various bolometer technologies are directly compared, estimating the noise equivalent power density (NEPD). Present tests show the fiber-optic bolometer to have NEPD of 5-10 W/m2 when compared to those of the resistive bolometer which can achieve <0.5 W/m2 in the laboratory, but this can degrade to 1-2 W/m2 or worse when installed on a tokamak. Concepts are discussed to improve the signal to noise ratio of this new fiber-optic bolometer by reducing the pillar height and adding thin metallic coatings, along with improving the spectral resolution of the interrogator.

Method and apparatus for coherent imaging of infrared energy

DOEpatents

Hutchinson, Donald P.

1998-01-01

A coherent camera system performs ranging, spectroscopy, and thermal imaging. Local oscillator radiation is combined with target scene radiation to enable heterodyne detection by the coherent camera's two-dimensional photodetector array. Versatility enables deployment of the system in either a passive mode (where no laser energy is actively transmitted toward the target scene) or an active mode (where a transmitting laser is used to actively illuminate the target scene). The two-dimensional photodetector array eliminates the need to mechanically scan the detector. Each element of the photodetector array produces an intermediate frequency signal that is amplified, filtered, and rectified by the coherent camera's integrated circuitry. By spectroscopic examination of the frequency components of each pixel of the detector array, a high-resolution, three-dimensional or holographic image of the target scene is produced for applications such as air pollution studies, atmospheric disturbance monitoring, and military weapons targeting.

Investigation of electrical noise in selenium-immersed thermistor bolometers

NASA Technical Reports Server (NTRS)

Tarpley, J. L.; Sarmiento, P. D.

1980-01-01

The selenium immersed, thermistor bolometer, IR detector failed due to spurious and escalating electrical noise outburst as a function of time at elevated temperatures during routine ground based testing in a space simulated environment. Spectrographic analysis of failed bolometers revealed selenium pure zones in the insulating selenium arsenic (Se-As) glass film which surrounds the active sintered Mn, Ni, Co oxide flake. The selenium pure film was identified as a potentially serious failure mechanism. Significant changes were instituted in the manufacturing techniques along with more stringent process controls which eliminated the selenium pure film and successfully produced 22study bolometers.

Film cameras or digital sensors? The challenge ahead for aerial imaging

USGS Publications Warehouse

Light, D.L.

1996-01-01

Cartographic aerial cameras continue to play the key role in producing quality products for the aerial photography business, and specifically for the National Aerial Photography Program (NAPP). One NAPP photograph taken with cameras capable of 39 lp/mm system resolution can contain the equivalent of 432 million pixels at 11 ??m spot size, and the cost is less than $75 per photograph to scan and output the pixels on a magnetic storage medium. On the digital side, solid state charge coupled device linear and area arrays can yield quality resolution (7 to 12 ??m detector size) and a broader dynamic range. If linear arrays are to compete with film cameras, they will require precise attitude and positioning of the aircraft so that the lines of pixels can be unscrambled and put into a suitable homogeneous scene that is acceptable to an interpreter. Area arrays need to be much larger than currently available to image scenes competitive in size with film cameras. Analysis of the relative advantages and disadvantages of the two systems show that the analog approach is more economical at present. However, as arrays become larger, attitude sensors become more refined, global positioning system coordinate readouts become commonplace, and storage capacity becomes more affordable, the digital camera may emerge as the imaging system for the future. Several technical challenges must be overcome if digital sensors are to advance to where they can support mapping, charting, and geographic information system applications.

Bolometer Simulation Using SPICE

NASA Technical Reports Server (NTRS)

Jones, Hollis H.; Aslam, Shahid; Lakew, Brook

2004-01-01

A general model is presented that assimilates the thermal and electrical properties of the bolometer - this block model demonstrates the Electro-Thermal Feedback (ETF) effect on the bolometers performance. This methodology is used to construct a SPICE model that by way of analogy combines the thermal and electrical phenomena into one simulation session. The resulting circuit diagram is presented and discussed.

Optical synthesizer for a large quadrant-array CCD camera: Center director's discretionary fund

NASA Technical Reports Server (NTRS)

Hagyard, Mona J.

1992-01-01

The objective of this program was to design and develop an optical device, an optical synthesizer, that focuses four contiguous quadrants of a solar image on four spatially separated CCD arrays that are part of a unique CCD camera system. This camera and the optical synthesizer will be part of the new NASA-Marshall Experimental Vector Magnetograph, and instrument developed to measure the Sun's magnetic field as accurately as present technology allows. The tasks undertaken in the program are outlined and the final detailed optical design is presented.

Evaluating video digitizer errors

NASA Astrophysics Data System (ADS)

Peterson, C.

2016-01-01

Analog output video cameras remain popular for recording meteor data. Although these cameras uniformly employ electronic detectors with fixed pixel arrays, the digitization process requires resampling the horizontal lines as they are output in order to reconstruct the pixel data, usually resulting in a new data array of different horizontal dimensions than the native sensor. Pixel timing is not provided by the camera, and must be reconstructed based on line sync information embedded in the analog video signal. Using a technique based on hot pixels, I present evidence that jitter, sync detection, and other timing errors introduce both position and intensity errors which are not present in cameras which internally digitize their sensors and output the digital data directly.

Optimization of Advanced ACTPol Transition Edge Sensor Bolometer Operation Using R(T,I) Transition Measurements

NASA Astrophysics Data System (ADS)

Salatino, Maria

2017-06-01

In the current submm and mm cosmology experiments the focal planes are populated by kilopixel transition edge sensors (TESes). Varying incoming power load requires frequent rebiasing of the TESes through standard current-voltage (IV) acquisition. The time required to perform IVs on such large arrays and the resulting transient heating of the bath reduces the sky observation time. We explore a bias step method that significantly reduces the time required for the rebiasing process. This exploits the detectors' responses to the injection of a small square wave signal on top of the dc bias current and knowledge of the shape of the detector transition R(T,I). This method has been tested on two detector arrays of the Atacama Cosmology Telescope (ACT). In this paper, we focus on the first step of the method, the estimate of the TES %Rn.

A Hot-electron Direct Detector for Radioastronomy

NASA Technical Reports Server (NTRS)

Karasik, Boris S.; McGrath, William R.; LeDuc, Henry G.; Gershenson, Michael E.

1999-01-01

A hot-electron transition-edge superconducting bolometer with adjustable thermal relaxation speed is proposed. The bolometer contacts are made from a superconductor with high critical temperature which blocks the thermal diffusion of hot carriers into the contacts. Thus electron-phonon interaction is the only mechanism for heat removal. The speed of thermal relaxation for hot electrons in a nanometer-size superconducting bolometer with T(sub c) = 100-300 mK is controlled by the elastic electron mean free path l. The relaxation rate behaves as T(sup 4)l at subkelvin temperatures and can be reduced by a factor of 10-100 by decreasing 1. Then an antenna- or wave guide-coupled bolometer with a time constant approx. = 10(exp -3) to 10(exp -4) s will exhibit photon-noise limited performance at millimeter and submillimeter wavelengths. The bolometer will have a figure-of-merit NEPtau = 10(exp -22) - 10(exp -21) W/Hz at 100 mK which is 10(exp 3) to 10(exp 4) times better (ie: smaller) than that of a state-of-the-art bolometer. A tremendous increase in speed and sensitivity will have a significant impact for observational mapping applications.

Detection of pointing errors with CMOS-based camera in intersatellite optical communications

NASA Astrophysics Data System (ADS)

Yu, Si-yuan; Ma, Jing; Tan, Li-ying

2005-01-01

For very high data rates, intersatellite optical communications hold a potential performance edge over microwave communications. Acquisition and Tracking problem is critical because of the narrow transmit beam. A single array detector in some systems performs both spatial acquisition and tracking functions to detect pointing errors, so both wide field of view and high update rate is required. The past systems tend to employ CCD-based camera with complex readout arrangements, but the additional complexity reduces the applicability of the array based tracking concept. With the development of CMOS array, CMOS-based cameras can employ the single array detector concept. The area of interest feature of the CMOS-based camera allows a PAT system to specify portion of the array. The maximum allowed frame rate increases as the size of the area of interest decreases under certain conditions. A commercially available CMOS camera with 105 fps @ 640×480 is employed in our PAT simulation system, in which only part pixels are used in fact. Beams angle varying in the field of view can be detected after getting across a Cassegrain telescope and an optical focus system. Spot pixel values (8 bits per pixel) reading out from CMOS are transmitted to a DSP subsystem via IEEE 1394 bus, and pointing errors can be computed by the centroid equation. It was shown in test that: (1) 500 fps @ 100×100 is available in acquisition when the field of view is 1mrad; (2)3k fps @ 10×10 is available in tracking when the field of view is 0.1mrad.

3D morphology reconstruction using linear array CCD binocular stereo vision imaging system

NASA Astrophysics Data System (ADS)

Pan, Yu; Wang, Jinjiang

2018-01-01

Binocular vision imaging system, which has a small field of view, cannot reconstruct the 3-D shape of the dynamic object. We found a linear array CCD binocular vision imaging system, which uses different calibration and reconstruct methods. On the basis of the binocular vision imaging system, the linear array CCD binocular vision imaging systems which has a wider field of view can reconstruct the 3-D morphology of objects in continuous motion, and the results are accurate. This research mainly introduces the composition and principle of linear array CCD binocular vision imaging system, including the calibration, capture, matching and reconstruction of the imaging system. The system consists of two linear array cameras which were placed in special arrangements and a horizontal moving platform that can pick up objects. The internal and external parameters of the camera are obtained by calibrating in advance. And then using the camera to capture images of moving objects, the results are then matched and 3-D reconstructed. The linear array CCD binocular vision imaging systems can accurately measure the 3-D appearance of moving objects, this essay is of great significance to measure the 3-D morphology of moving objects.

Feasibility Study of Utilizing Existing Infrared Array Cameras for Daylight Star Tracking on NASA's Ultra Long Duration Balloon (ULDB) Missions

NASA Technical Reports Server (NTRS)

Tueller, Jack (Technical Monitor); Fazio, Giovanni G.; Tolls, Volker

2004-01-01

The purpose of this study was to investigate the feasibility of developing a daytime star tracker for ULDB flights using a commercially available off-the-shelf infrared array camera. This report describes the system used for ground-based tests, the observations, the test results, and gives recommendations for continued development.

A Hot-electron Direct Detector for Radioastronomy

NASA Technical Reports Server (NTRS)

Karasik, B. S.; McGrath, W. R.; LeDuc, H. G.

2000-01-01

A new approach is proposed to improve the sensitivity of direct-detection bolometers. The idea is to adjust a speed of the thermal relaxation of hot-electrons in a nanometer size normal metal or superconductive transition edge bolometer by controlling the elastic electron mean free path. If the bolometer contacts are made of a superconductor with high critical temperature then the thermal diffusion into the contacts is absent because of the Andreev's reflection and the electron-phonon relaxation is the only mechanism for heat removal. The relaxation rate should behave as 7(exp 4)l at subkelvin temperatures (l is the electron elastic mean free path) and can be reduced by factor of 10 - 100 by decreasing l. Then an antenna- or waveguide-coupled bolometer with a time constant approx. 10(exp -3) to 10(exp -5) S at T approx. = 0.1 - 0.3 K will exhibit photon-noise limited performance in millimeter and subn-millimeter range. The bolometer will have a figure-of-merit NEk square root of tau approx. = 10(exp -22) 10(exp -21) W/Hz at 100 mK which is 10(exp 3) times smaller than that of a state-of-the-art bolometer. This will allow for a tremendous increase in speed which will have a significant impact for observational mapping applications. Alternatively, the bolometer could operate at higher temperature with still superior sensitivity This research was performed by the Center for Space Microelectronics Technology, JPL, California Institute of Technology, under the contract for NASA.

Motorcycle detection and counting using stereo camera, IR camera, and microphone array

NASA Astrophysics Data System (ADS)

Ling, Bo; Gibson, David R. P.; Middleton, Dan

2013-03-01

Detection, classification, and characterization are the key to enhancing motorcycle safety, motorcycle operations and motorcycle travel estimation. Average motorcycle fatalities per Vehicle Mile Traveled (VMT) are currently estimated at 30 times those of auto fatalities. Although it has been an active research area for many years, motorcycle detection still remains a challenging task. Working with FHWA, we have developed a hybrid motorcycle detection and counting system using a suite of sensors including stereo camera, thermal IR camera and unidirectional microphone array. The IR thermal camera can capture the unique thermal signatures associated with the motorcycle's exhaust pipes that often show bright elongated blobs in IR images. The stereo camera in the system is used to detect the motorcyclist who can be easily windowed out in the stereo disparity map. If the motorcyclist is detected through his or her 3D body recognition, motorcycle is detected. Microphones are used to detect motorcycles that often produce low frequency acoustic signals. All three microphones in the microphone array are placed in strategic locations on the sensor platform to minimize the interferences of background noises from sources such as rain and wind. Field test results show that this hybrid motorcycle detection and counting system has an excellent performance.

ARNICA: the Arcetri Observatory NICMOS3 imaging camera

NASA Astrophysics Data System (ADS)

Lisi, Franco; Baffa, Carlo; Hunt, Leslie K.

1993-10-01

ARNICA (ARcetri Near Infrared CAmera) is the imaging camera for the near infrared bands between 1.0 and 2.5 micrometers that Arcetri Observatory has designed and built as a general facility for the TIRGO telescope (1.5 m diameter, f/20) located at Gornergrat (Switzerland). The scale is 1' per pixel, with sky coverage of more than 4' X 4' on the NICMOS 3 (256 X 256 pixels, 40 micrometers side) detector array. The optical path is compact enough to be enclosed in a 25.4 cm diameter dewar; the working temperature is 76 K. The camera is remotely controlled by a 486 PC, connected to the array control electronics via a fiber-optics link. A C-language package, running under MS-DOS on the 486 PC, acquires and stores the frames, and controls the timing of the array. We give an estimate of performance, in terms of sensitivity with an assigned observing time, along with some details on the main parameters of the NICMOS 3 detector.

Performance and field tests of a handheld Compton camera using 3-D position-sensitive scintillators coupled to multi-pixel photon counter arrays

NASA Astrophysics Data System (ADS)

Kishimoto, A.; Kataoka, J.; Nishiyama, T.; Fujita, T.; Takeuchi, K.; Okochi, H.; Ogata, H.; Kuroshima, H.; Ohsuka, S.; Nakamura, S.; Hirayanagi, M.; Adachi, S.; Uchiyama, T.; Suzuki, H.

2014-11-01

After the nuclear disaster in Fukushima, radiation decontamination has become particularly urgent. To help identify radiation hotspots and ensure effective decontamination operation, we have developed a novel Compton camera based on Ce-doped Gd3Al2Ga3O12 scintillators and multi-pixel photon counter (MPPC) arrays. Even though its sensitivity is several times better than that of other cameras being tested in Fukushima, we introduce a depth-of-interaction (DOI) method to further improve the angular resolution. For gamma rays, the DOI information, in addition to 2-D position, is obtained by measuring the pulse-height ratio of the MPPC arrays coupled to ends of the scintillator. We present the detailed performance and results of various field tests conducted in Fukushima with the prototype 2-D and DOI Compton cameras. Moreover, we demonstrate stereo measurement of gamma rays that enables measurement of not only direction but also approximate distance to radioactive hotspots.

The NASA - Arc 10/20 micron camera

NASA Technical Reports Server (NTRS)

Roellig, T. L.; Cooper, R.; Deutsch, L. K.; Mccreight, C.; Mckelvey, M.; Pendleton, Y. J.; Witteborn, F. C.; Yuen, L.; Mcmahon, T.; Werner, M. W.

1994-01-01

A new infrared camera (AIR Camera) has been developed at NASA - Ames Research Center for observations from ground-based telescopes. The heart of the camera is a Hughes 58 x 62 pixel Arsenic-doped Silicon detector array that has the spectral sensitivity range to allow observations in both the 10 and 20 micron atmospheric windows.

Optomechanical System Development of the AWARE Gigapixel Scale Camera

NASA Astrophysics Data System (ADS)

Son, Hui S.

Electronic focal plane arrays (FPA) such as CMOS and CCD sensors have dramatically improved to the point that digital cameras have essentially phased out film (except in very niche applications such as hobby photography and cinema). However, the traditional method of mating a single lens assembly to a single detector plane, as required for film cameras, is still the dominant design used in cameras today. The use of electronic sensors and their ability to capture digital signals that can be processed and manipulated post acquisition offers much more freedom of design at system levels and opens up many interesting possibilities for the next generation of computational imaging systems. The AWARE gigapixel scale camera is one such computational imaging system. By utilizing a multiscale optical design, in which a large aperture objective lens is mated with an array of smaller, well corrected relay lenses, we are able to build an optically simple system that is capable of capturing gigapixel scale images via post acquisition stitching of the individual pictures from the array. Properly shaping the array of digital cameras allows us to form an effectively continuous focal surface using off the shelf (OTS) flat sensor technology. This dissertation details developments and physical implementations of the AWARE system architecture. It illustrates the optomechanical design principles and system integration strategies we have developed through the course of the project by summarizing the results of the two design phases for AWARE: AWARE-2 and AWARE-10. These systems represent significant advancements in the pursuit of scalable, commercially viable snapshot gigapixel imaging systems and should serve as a foundation for future development of such systems.

Method for determining and displaying the spacial distribution of a spectral pattern of received light

DOEpatents

Bennett, C.L.

1996-07-23

An imaging Fourier transform spectrometer is described having a Fourier transform infrared spectrometer providing a series of images to a focal plane array camera. The focal plane array camera is clocked to a multiple of zero crossing occurrences as caused by a moving mirror of the Fourier transform infrared spectrometer and as detected by a laser detector such that the frame capture rate of the focal plane array camera corresponds to a multiple of the zero crossing rate of the Fourier transform infrared spectrometer. The images are transmitted to a computer for processing such that representations of the images as viewed in the light of an arbitrary spectral ``fingerprint`` pattern can be displayed on a monitor or otherwise stored and manipulated by the computer. 2 figs.

Optimising the multiplex factor of the frequency domain multiplexed readout of the TES-based microcalorimeter imaging array for the X-IFU instrument on the Athena x-ray observatory

NASA Astrophysics Data System (ADS)

van der Kuur, J.; Gottardi, L. G.; Akamatsu, H.; van Leeuwen, B. J.; den Hartog, R.; Haas, D.; Kiviranta, M.; Jackson, B. J.

2016-07-01

Athena is a space-based X-ray observatory intended for exploration of the hot and energetic universe. One of the science instruments on Athena will be the X-ray Integrated Field Unit (X-IFU), which is a cryogenic X-ray spectrometer, based on a large cryogenic imaging array of Transition Edge Sensors (TES) based microcalorimeters operating at a temperature of 100mK. The imaging array consists of 3800 pixels providing 2.5 eV spectral resolution, and covers a field of view with a diameter of of 5 arc minutes. Multiplexed readout of the cryogenic microcalorimeter array is essential to comply with the cooling power and complexity constraints on a space craft. Frequency domain multiplexing has been under development for the readout of TES-based detectors for this purpose, not only for the X-IFU detector arrays but also for TES-based bolometer arrays for the Safari instrument of the Japanese SPICA observatory. This paper discusses the design considerations which are applicable to optimise the multiplex factor within the boundary conditions as set by the space craft. More specifically, the interplay between the science requirements such as pixel dynamic range, pixel speed, and cross talk, and the space craft requirements such as the power dissipation budget, available bandwidth, and electromagnetic compatibility will be discussed.

Silicon Hot-Electron Bolometers

NASA Technical Reports Server (NTRS)

Stevenson, Thomas R.; Hsieh, Wen-Ting; Mitchell, Robert R.; Isenberg, Hal D.; Stahle, Carl M.; Cao, Nga T.; Schneider, Gideon; Travers, Douglas E.; Moseley, S. Harvey; Wollack, Edward J.

2004-01-01

We discuss a new type of direct detector, a silicon hot-electron bolometer, for measurements in the far-infrared and submillimeter spectral ranges. High performance bolometers can be made using the electron-phonon conductance in heavily doped silicon to provide thermal isolation from the cryogenic bath. Noise performance is expected to be near thermodynamic limits, allowing background limited performance for many far infrared and submillimeter photometric and spectroscopic applications.

Development of plasma bolometers using fiber-optic temperature sensors

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

Reinke, M. L., E-mail: reinkeml@ornl.gov; Han, M.; Liu, G.

Measurements of radiated power in magnetically confined plasmas are important for exhaust studies in present experiments and expected to be a critical diagnostic for future fusion reactors. Resistive bolometer sensors have long been utilized in tokamaks and helical devices but suffer from electromagnetic interference (EMI). Results are shown from initial testing of a new bolometer concept based on fiber-optic temperature sensor technology. A small, 80 μm diameter, 200 μm long silicon pillar attached to the end of a single mode fiber-optic cable acts as a Fabry–Pérot cavity when broadband light, λ{sub o} ∼ 1550 nm, is transmitted along the fiber.more » Changes in temperature alter the optical path length of the cavity primarily through the thermo-optic effect, resulting in a shift of fringes reflected from the pillar detected using an I-MON 512 OEM spectrometer. While initially designed for use in liquids, this sensor has ideal properties for use as a plasma bolometer: a time constant, in air, of ∼150 ms, strong absorption in the spectral range of plasma emission, immunity to local EMI, and the ability to measure changes in temperature remotely. Its compact design offers unique opportunities for integration into the vacuum environment in places unsuitable for a resistive bolometer. Using a variable focus 5 mW, 405 nm, modulating laser, the signal to noise ratio versus power density of various bolometer technologies are directly compared, estimating the noise equivalent power density (NEPD). Present tests show the fiber-optic bolometer to have NEPD of 5-10 W/m{sup 2} when compared to those of the resistive bolometer which can achieve <0.5 W/m{sup 2} in the laboratory, but this can degrade to 1-2 W/m{sup 2} or worse when installed on a tokamak. Concepts are discussed to improve the signal to noise ratio of this new fiber-optic bolometer by reducing the pillar height and adding thin metallic coatings, along with improving the spectral resolution of the interrogator.« less

Plenoptic camera based on a liquid crystal microlens array

NASA Astrophysics Data System (ADS)

Lei, Yu; Tong, Qing; Zhang, Xinyu; Sang, Hongshi; Xie, Changsheng

2015-09-01

A type of liquid crystal microlens array (LCMLA) with tunable focal length by the voltage signals applied between its top and bottom electrodes, is fabricated and then the common optical focusing characteristics are tested. The relationship between the focal length and the applied voltage signals is given. The LCMLA is integrated with an image sensor and further coupled with a main lens so as to construct a plenoptic camera. Several raw images at different voltage signals applied are acquired and contrasted through the LCMLA-based plenoptic camera constructed by us. Our experiments demonstrate that through utilizing a LCMLA in a plenoptic camera, the focused zone of the LCMLA-based plenoptic camera can be shifted effectively only by changing the voltage signals loaded between the electrodes of the LCMLA, which is equivalent to the extension of the depth of field.

Cryogenic system for the ArTeMiS large sub millimeter camera

NASA Astrophysics Data System (ADS)

Ercolani, E.; Relland, J.; Clerc, L.; Duband, L.; Jourdan, T.; Talvard, M.; Le Pennec, J.; Martignac, J.; Visticot, F.

2014-07-01

A new photonic camera has been developed in the framework of the ArTéMis project (Bolometers architecture for large field of view ground based telescopes in the sub-millimeter). This camera scans the sky in the sub-millimeter range at simultaneously three different wavelengths, namely 200 μm, 350 μm, 450 μm, and is installed inside the APEX telescope located at 5100m above sea level in Chile. Bolometric detectors cooled to 300 mK are used in the camera, which is integrated in an original cryostat developed at the low temperature laboratory (SBT) of the INAC institut. This cryostat contains filters, optics, mirrors and detectors which have to be implemented according to mass, size and stiffness requirements. As a result the cryostat exhibits an unusual geometry. The inner structure of the cryostat is a 40 K plate which acts as an optical bench and is bound to the external vessel through two hexapods, one fixed and the other one mobile thanks to a ball bearing. Once the cryostat is cold, this characteristic enabled all the different elements to be aligned with the optical axis. The cryogenic chain is built around a pulse tube cooler (40 K and 4 K) coupled to a double stage helium sorption cooler (300 mK). The cryogenic and vacuum processes are managed by a Siemens PLC and all the data are showed and stored on a CEA SCADA system. This paper describes the mechanical and thermal design of the cryostat, its command control, and the first thermal laboratory tests. This work was carried out in collaboration with the Astrophysics laboratory SAp of the IRFU institut. SAp and SBT have installed the camera in July 2013 inside the Cassegrain cabin of APEX.

Frequency division multiplexed readout of TES detectors with baseband feedback

NASA Astrophysics Data System (ADS)

den Hartog, R.; Audley, M. D.; Beyer, J.; Bruijn, M. P.; de Korte, P.; Gottardi, L.; Hijmering, R.; Jackson, B.; Nieuwenhuizen, A.; van der Kuur, J.; van Leeuwen, B.-J.; Van Loon, D.

2012-09-01

SRON is developing an electronic system for the multiplexed read-out of an array of transition edge sensors (TES) by combining the techniques of frequency domain multiplexing (FDM) with base-band feedback (BBFB). The astronomical applications are the read-out of soft X-ray microcalorimeters and the far-infrared bolometers for the SAFARI instrument on the Japanese mission SPICA. In this paper we derive the requirements for the read-out system regarding noise and dynamic range in the context of the SAFARI instrument, and demonstrate that the current experimental prototype is capable of simultaneously locking 57 channels and complies with these requirements.

Millimeter and submillimeter observations from the Atacama plateau and high altitude balloons

NASA Astrophysics Data System (ADS)

Devlin, Mark

2002-05-01

A new generation of ground-based and sub-orbital platforms will be operational in the next few years. These telescopes will operate from high sites in Chile and Antarctica, and airborne platforms where the atmosphere is transparent enough to allow sensitive measurements in the millimeter and submillimeter bands. The telescopes will employ state-of-the-art instrumentation including large format bolometer arrays and spectrometers. I will discuss the results of our observations in the Atacama region of Chile (MAT/TOCO), our future observations on the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) now under construction, and our proposed Atacama Cosmology Telescope (ACT). .

Neutrinoless double-beta decay search with CUORE and CUORE-0 experiments

DOE PAGES

Moggi, N.; Artusa, D. R.; F. T. Avignone; ...

2015-03-24

The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for the neutrinoless double-beta decays. Observation of the process would unambiguously establish that neutrinos are Majorana particles and provide information on their absolute mass scale hierarchy. CUORE is now under construction and will consist of an array of 988 TeO 2 crystal bolometers operated at 10 mK, but the first tower (CUORE-0) is already taking data. The experimental techniques used will be presented as well as the preliminary CUORE-0 results. The current status of the full-mass experiment and its expected sensitivity will then be discussed.

Concave Surround Optics for Rapid Multi-View Imaging

DTIC Science & Technology

2006-11-01

thus is amenable to capturing dynamic events avoiding the need to construct and calibrate an array of cameras. We demonstrate the system with a high...hard to assemble and calibrate . In this paper we present an optical system capable of rapidly moving the viewpoint around a scene. Our system...flexibility, large camera arrays are typically expensive and require significant effort to calibrate temporally, geometrically and chromatically

EVA 2 activity on Flight Day 5 to survey the HST solar array panels

NASA Image and Video Library

1997-02-15

STS082-719-002 (14 Feb. 1997) --- Astronaut Joseph R. Tanner (right) stands on the end of Discovery's Remote Manipulator System (RMS) arm and aims a camera at the solar array panels on the Hubble Space Telescope (HST) as astronaut Gregory J. Harbaugh assists. The second Extravehicular Activity (EVA) photograph was taken with a 70mm camera from inside Discovery's cabin.

PNIC - A near infrared camera for testing focal plane arrays

NASA Astrophysics Data System (ADS)

Hereld, Mark; Harper, D. A.; Pernic, R. J.; Rauscher, Bernard J.

1990-07-01

This paper describes the design and the performance of the Astrophysical Research Consortium prototype near-infrared camera (pNIC) designed to test focal plane arrays both on and off the telescope. Special attention is given to the detector in pNIC, the mechanical and optical designs, the electronics, and the instrument interface. Experiments performed to illustrate the most salient aspects of pNIC are described.

The system analysis of light field information collection based on the light field imaging

NASA Astrophysics Data System (ADS)

Wang, Ye; Li, Wenhua; Hao, Chenyang

2016-10-01

Augmented reality(AR) technology is becoming the study focus, and the AR effect of the light field imaging makes the research of light field camera attractive. The micro array structure was adopted in most light field information acquisition system(LFIAS) since emergence of light field camera, micro lens array(MLA) and micro pinhole array(MPA) system mainly included. It is reviewed in this paper the structure of the LFIAS that the Light field camera commonly used in recent years. LFIAS has been analyzed based on the theory of geometrical optics. Meanwhile, this paper presents a novel LFIAS, plane grating system, we call it "micro aperture array(MAA." And the LFIAS are analyzed based on the knowledge of information optics; This paper proves that there is a little difference in the multiple image produced by the plane grating system. And the plane grating system can collect and record the amplitude and phase information of the field light.

Research on Geometric Calibration of Spaceborne Linear Array Whiskbroom Camera

PubMed Central

Sheng, Qinghong; Wang, Qi; Xiao, Hui; Wang, Qing

2018-01-01

The geometric calibration of a spaceborne thermal-infrared camera with a high spatial resolution and wide coverage can set benchmarks for providing an accurate geographical coordinate for the retrieval of land surface temperature. The practice of using linear array whiskbroom Charge-Coupled Device (CCD) arrays to image the Earth can help get thermal-infrared images of a large breadth with high spatial resolutions. Focusing on the whiskbroom characteristics of equal time intervals and unequal angles, the present study proposes a spaceborne linear-array-scanning imaging geometric model, whilst calibrating temporal system parameters and whiskbroom angle parameters. With the help of the YG-14—China’s first satellite equipped with thermal-infrared cameras of high spatial resolution—China’s Anyang Imaging and Taiyuan Imaging are used to conduct an experiment of geometric calibration and a verification test, respectively. Results have shown that the plane positioning accuracy without ground control points (GCPs) is better than 30 pixels and the plane positioning accuracy with GCPs is better than 1 pixel. PMID:29337885

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-07

S61-E-020 (7 Dec 1993) --- This close-up view of one of two Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Endeavour's crew captured the HST on December 4, 1993, in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

Multimode bolometer development for the PIXIE instrument

NASA Astrophysics Data System (ADS)

Nagler, Peter C.; Crowley, Kevin T.; Denis, Kevin L.; Devasia, Archana M.; Fixsen, Dale J.; Kogut, Alan J.; Manos, George; Porter, Scott; Stevenson, Thomas R.

2016-07-01

The Primordial Inflation Explorer (PIXIE) is an Explorer-class mission concept designed to measure the polar- ization and absolute intensity of the cosmic microwave background. In the following, we report on the design, fabrication, and performance of the multimode polarization-sensitive bolometers for PIXIE, which are based on silicon thermistors. In particular we focus on several recent advances in the detector design, including the implementation of a scheme to greatly raise the frequencies of the internal vibrational modes of the large-area, low-mass optical absorber structure consisting of a grid of micromachined, ion-implanted silicon wires. With ˜ 30 times the absorbing area of the spider-web bolometers used by Planck, the tensioning scheme enables the PIXIE bolometers to be robust in the vibrational and acoustic environment at launch of the space mission. More generally, it could be used to reduce microphonic sensitivity in other types of low temperature detectors. We also report on the performance of the PIXIE bolometers in a dark cryogenic environment.

Multimode Bolometer Development for the PIXIE Instrument

NASA Technical Reports Server (NTRS)

Nagler, Peter C.; Crowley, Kevin T.; Denis, Kevin L.; Devasia, Archana M.; Fixsen, Dale J.; Kogut, Alan J.; Manos, George; Porter, Scott; Stevenson, Thomas R.

2016-01-01

The Primordial Inflation Explorer (PIXIE) is an Explorer-class mission concept designed to measure the polarization and absolute intensity of the cosmic microwave background. In the following, we report on the design, fabrication, and performance of the multimode polarization-sensitive bolometers for PIXIE, which are based on silicon thermistors. In particular we focus on several recent advances in the detector design, including the implementation of a scheme to greatly raise the frequencies of the internal vibrational modes of the large-area, low-mass optical absorber structure consisting of a grid of micromachined, ion-implanted silicon wires. With approximately 30 times the absorbing area of the spider-web bolometers used by Planck, the tensioning scheme enables the PIXIE bolometers to be robust in the vibrational and acoustic environment at launch of the space mission. More generally, it could be used to reduce microphonic sensitivity in other types of low temperature detectors. We also report on the performance of the PIXIE bolometers in a dark cryogenic environment.

Multimode Bolometer Development for the Primordial Inflation Explorer (PIXIE) Instrument

NASA Technical Reports Server (NTRS)

Nagler, Peter C.; Crowley, Kevin T.; Denis, Kevin L.; Devasia, Archana M.; Fixsen, Dale J.; Kogut, Alan J.; Manos, George; Porter, Scott; Stevenson, Thomas R.

2016-01-01

The Primordial Inflation Explorer (PIXIE) is an Explorer-class mission concept designed to measure the polarization and absolute intensity of the cosmic microwave background [1]. In this work, we report on the design, fabrication, and performance of the multimode polarization-sensitive bolometers for PIXIE, which are based on silicon thermistors. In particular we focus on several recent advances in the detector design, including the implementation of a tensioning scheme to greatly raise the frequencies of the internal vibrational modes of the large-area, low-mass optical absorber structure consisting of a grid of micromachined, ion-implanted silicon wires. With 30 times the absorbing area of the spider-web bolometers used by Planck, the tensioning scheme enables the PIXIE bolometers to be robust in the vibrational and acoustic environment at launch of the space mission. More generally, it could be used to reduce microphonic sensitivity in other types of low temperature detectors. We also report on the performance of the PIXIE bolometers in a dark cryogenic environment.

Film Vetoes for Alpha Background Rejection in Bolometer Detectors

NASA Astrophysics Data System (ADS)

Deporzio, Nicholas; Bucci, Carlo; Canonica, Lucia; Divacri, Marialaura; Cuore Collaboration; Absurd Team

2015-04-01

This study characterizes the effectiveness of encasing bolometer detectors in scintillator, metal ionization, and more exotic films to veto alpha radiation background. Bolometers are highly susceptible to alpha background and a successful veto should boost the statistical strength, speed, and signal-background ratio of bolometer particle searches. Plastic scintillator films are cooled to bolometer temperatures and bombarded with 1.4 MeV to 6.0 MeV alpha particles representative of detector conditions. Photomultipliers detect the keV range scintillation light and produce a veto signal. Also, layered films of a primary metal, dielectric, and secondary metal, such as gold-polyethylene-gold films, are cooled to milli-kelvin temperatures and biased with 0.1V to 100V to produce a current signal when incident 1.4 MeV to 6.0 MeV alpha particles ionize conduction paths through the film. Veto signals are characterized by their affect on bolometer detection of 865 keV target signals. Similar methods are applied to more exotic films. Early results show scintillator films raise target signal count rate and suppress counts above target energy by at least a factor of 10. This indicates scintillation vetoes are effective and that metal ionization and other films under study will also be effective.

Multi-Angle Snowflake Camera Value-Added Product

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

Shkurko, Konstantin; Garrett, T.; Gaustad, K

The Multi-Angle Snowflake Camera (MASC) addresses a need for high-resolution multi-angle imaging of hydrometeors in freefall with simultaneous measurement of fallspeed. As illustrated in Figure 1, the MASC consists of three cameras, separated by 36°, each pointing at an identical focal point approximately 10 cm away. Located immediately above each camera, a light aims directly at the center of depth of field for its corresponding camera. The focal point at which the cameras are aimed lies within a ring through which hydrometeors fall. The ring houses a system of near-infrared emitter-detector pairs, arranged in two arrays separated vertically by 32more » mm. When hydrometeors pass through the lower array, they simultaneously trigger all cameras and lights. Fallspeed is calculated from the time it takes to traverse the distance between the upper and lower triggering arrays. The trigger electronics filter out ambient light fluctuations associated with varying sunlight and shadows. The microprocessor onboard the MASC controls the camera system and communicates with the personal computer (PC). The image data is sent via FireWire 800 line, and fallspeed (and camera control) is sent via a Universal Serial Bus (USB) line that relies on RS232-over-USB serial conversion. See Table 1 for specific details on the MASC located at the Oliktok Point Mobile Facility on the North Slope of Alaska. The value-added product (VAP) detailed in this documentation analyzes the raw data (Section 2.0) using Python: images rely on OpenCV image processing library and derived aggregated statistics rely on some clever averaging. See Sections 4.1 and 4.2 for more details on what variables are computed.« less

STS-32 photographic equipment (cameras,lenses,film magazines) on flight deck

NASA Technical Reports Server (NTRS)

1990-01-01

STS-32 photographic equipment is displayed on the aft flight deck of Columbia, Orbiter Vehicle (OV) 102. On the payload station are a dual camera mount with two handheld HASSELBLAD cameras, camera lenses, and film magazines. This array of equipment will be used to record onboard activities and observations of the Earth's surface.

A Hot-Electron Far-Infrared Direct Detector

NASA Technical Reports Server (NTRS)

Karasik, B. S.; McGrath, W. R.; LeDuc, H. G.

2000-01-01

A new approach is proposed to improve the sensitivity of direct-detection bolometers at millimeter, submillimeter and far-infrared wavelengths. The idea is to adjust a speed of the thermal relaxation of hot-electrons in a nanometer size normal metal or super-conductive transition edge bolometer by controlling the elastic electron mean free path. If the bolometer contacts are made of a superconductor with high critical temperature (Nb, Pb etc.) then the thermal diffusion into the contacts is absent because of the Andreev's reflection and the electron-phonon relaxation is the only mechanism for heat removal. The relaxation rate should behave as T(sup 4)l at subkelvin temperatures (l is the electron elastic mean free path) and can be reduced by factor of 10-100 by decreasing l. Then an antenna- or waveguide-coupled bolometer with a time constant about 10(exp -3) to 10(exp -5) s at T approximately equals 0.1-0.3 K will exhibit photon-noise limited performance in millimeter and submillimeter range. The choice of the bolometer material is a tradeoff between a low electron heat capacity and fabrication. A state-of-the-art bolometer currently offers NEP = 10(exp -17) W(Square root of (Hz)) at 100 mK along with a approximately equals 2 msec time constant. The bolometer we propose will have a figure-of-merit, NEP(square root (r)), which is 10(exp 3) times smaller. This will allow for a tremendous increase in speed which will have a significant impact for observational mapping applications. Alternatively, the bolometer could operate at higher temperature with still superior sensitivity. This device can significantly increase a science return and reduce the cost for future observational missions. This research was performed by the Center for Space Microelectronics Technology, Jet Propulsion Laboratory, California Institute of Technology, and was sponsored by NASA, Office of Space Science.

Condenser for photolithography system

DOEpatents

Sweatt, William C.

2004-03-02

A condenser for a photolithography system, in which a mask image from a mask is projected onto a wafer through a camera having an entrance pupil, includes a source of propagating radiation, a first mirror illuminated by the radiation, a mirror array illuminated by the radiation reflected from said first mirror, and a second mirror illuminated by the radiation reflected from the array. The mirror array includes a plurality of micromirrors. Each of the micromirrors is selectively actuatable independently of each other. The first mirror and the second mirror are disposed such that the source is imaged onto a plane of the mask and the mirror array is imaged into the entrance pupil of the camera.

Upgraded cameras for the HESS imaging atmospheric Cherenkov telescopes

NASA Astrophysics Data System (ADS)

Giavitto, Gianluca; Ashton, Terry; Balzer, Arnim; Berge, David; Brun, Francois; Chaminade, Thomas; Delagnes, Eric; Fontaine, Gérard; Füßling, Matthias; Giebels, Berrie; Glicenstein, Jean-François; Gräber, Tobias; Hinton, James; Jahnke, Albert; Klepser, Stefan; Kossatz, Marko; Kretzschmann, Axel; Lefranc, Valentin; Leich, Holger; Lüdecke, Hartmut; Lypova, Iryna; Manigot, Pascal; Marandon, Vincent; Moulin, Emmanuel; de Naurois, Mathieu; Nayman, Patrick; Penno, Marek; Ross, Duncan; Salek, David; Schade, Markus; Schwab, Thomas; Simoni, Rachel; Stegmann, Christian; Steppa, Constantin; Thornhill, Julian; Toussnel, François

2016-08-01

The High Energy Stereoscopic System (H.E.S.S.) is an array of five imaging atmospheric Cherenkov telescopes, sensitive to cosmic gamma rays of energies between 30 GeV and several tens of TeV. Four of them started operations in 2003 and their photomultiplier tube (PMT) cameras are currently undergoing a major upgrade, with the goals of improving the overall performance of the array and reducing the failure rate of the ageing systems. With the exception of the 960 PMTs, all components inside the camera have been replaced: these include the readout and trigger electronics, the power, ventilation and pneumatic systems and the control and data acquisition software. New designs and technical solutions have been introduced: the readout makes use of the NECTAr analog memory chip, which samples and stores the PMT signals and was developed for the Cherenkov Telescope Array (CTA). The control of all hardware subsystems is carried out by an FPGA coupled to an embedded ARM computer, a modular design which has proven to be very fast and reliable. The new camera software is based on modern C++ libraries such as Apache Thrift, ØMQ and Protocol buffers, offering very good performance, robustness, flexibility and ease of development. The first camera was upgraded in 2015, the other three cameras are foreseen to follow in fall 2016. We describe the design, the performance, the results of the tests and the lessons learned from the first upgraded H.E.S.S. camera.

Ga:Ge array development

NASA Technical Reports Server (NTRS)

Young, Erick T.; Rieke, G. H.; Low, Frank J.; Haller, E. E.; Beeman, J. W.

1989-01-01

Work at the University of Arizona and at Lawrence Berkeley Laboratory on the development of a far infrared array camera for the Multiband Imaging Photometer on the Space Infrared Telescope Facility (SIRTF) is discussed. The camera design uses stacked linear arrays of Ge:Ga photoconductors to make a full two-dimensional array. Initial results from a 1 x 16 array using a thermally isolated J-FET readout are presented. Dark currents below 300 electrons s(exp -1) and readout noises of 60 electrons were attained. Operation of these types of detectors in an ionizing radiation environment are discussed. Results of radiation testing using both low energy gamma rays and protons are given. Work on advanced C-MOS cascode readouts that promise lower temperature operation and higher levels of performance than the current J-FET based devices is described.

The Advanced Gamma-ray Imaging System (AGIS): Real Time Stereoscopic Array Trigger

NASA Astrophysics Data System (ADS)

Byrum, K.; Anderson, J.; Buckley, J.; Cundiff, T.; Dawson, J.; Drake, G.; Duke, C.; Haberichter, B.; Krawzcynski, H.; Krennrich, F.; Madhavan, A.; Schroedter, M.; Smith, A.

2009-05-01

Future large arrays of Imaging Atmospheric Cherenkov telescopes (IACTs) such as AGIS and CTA are conceived to comprise of 50 - 100 individual telescopes each having a camera with 10**3 to 10**4 pixels. To maximize the capabilities of such IACT arrays with a low energy threshold, a wide field of view and a low background rate, a sophisticated array trigger is required. We describe the design of a stereoscopic array trigger that calculates image parameters and then correlates them across a subset of telescopes. Fast Field Programmable Gate Array technology allows to use lookup tables at the array trigger level to form a real-time pattern recognition trigger tht capitalizes on the multiple view points of the shower at different shower core distances. A proof of principle system is currently under construction. It is based on 400 MHz FPGAs and the goal is for camera trigger rates of up to 10 MHz and a tunable cosmic-ray background suppression at the array level.

Using a plenoptic camera to measure distortions in wavefronts affected by atmospheric turbulence

NASA Astrophysics Data System (ADS)

Eslami, Mohammed; Wu, Chensheng; Rzasa, John; Davis, Christopher C.

2012-10-01

Ideally, as planar wave fronts travel through an imaging system, all rays, or vectors pointing in the direction of the propagation of energy are parallel, and thus the wave front is focused to a particular point. If the wave front arrives at an imaging system with energy vectors that point in different directions, each part of the wave front will be focused at a slightly different point on the sensor plane and result in a distorted image. The Hartmann test, which involves the insertion of a series of pinholes between the imaging system and the sensor plane, was developed to sample the wavefront at different locations and measure the distortion angles at different points in the wave front. An adaptive optic system, such as a deformable mirror, is then used to correct for these distortions and allow the planar wave front to focus at the point desired on the sensor plane, thereby correcting the distorted image. The apertures of a pinhole array limit the amount of light that reaches the sensor plane. By replacing the pinholes with a microlens array each bundle of rays is focused to brighten the image. Microlens arrays are making their way into newer imaging technologies, such as "light field" or "plenoptic" cameras. In these cameras, the microlens array is used to recover the ray information of the incoming light by using post processing techniques to focus on objects at different depths. The goal of this paper is to demonstrate the use of these plenoptic cameras to recover the distortions in wavefronts. Taking advantage of the microlens array within the plenoptic camera, CODE-V simulations show that its performance can provide more information than a Shack-Hartmann sensor. Using the microlens array to retrieve the ray information and then backstepping through the imaging system provides information about distortions in the arriving wavefront.

Camera-Model Identification Using Markovian Transition Probability Matrix

NASA Astrophysics Data System (ADS)

Xu, Guanshuo; Gao, Shang; Shi, Yun Qing; Hu, Ruimin; Su, Wei

Detecting the (brands and) models of digital cameras from given digital images has become a popular research topic in the field of digital forensics. As most of images are JPEG compressed before they are output from cameras, we propose to use an effective image statistical model to characterize the difference JPEG 2-D arrays of Y and Cb components from the JPEG images taken by various camera models. Specifically, the transition probability matrices derived from four different directional Markov processes applied to the image difference JPEG 2-D arrays are used to identify statistical difference caused by image formation pipelines inside different camera models. All elements of the transition probability matrices, after a thresholding technique, are directly used as features for classification purpose. Multi-class support vector machines (SVM) are used as the classification tool. The effectiveness of our proposed statistical model is demonstrated by large-scale experimental results.

Single-snapshot 2D color measurement by plenoptic imaging system

NASA Astrophysics Data System (ADS)

Masuda, Kensuke; Yamanaka, Yuji; Maruyama, Go; Nagai, Sho; Hirai, Hideaki; Meng, Lingfei; Tosic, Ivana

2014-03-01

Plenoptic cameras enable capture of directional light ray information, thus allowing applications such as digital refocusing, depth estimation, or multiband imaging. One of the most common plenoptic camera architectures contains a microlens array at the conventional image plane and a sensor at the back focal plane of the microlens array. We leverage the multiband imaging (MBI) function of this camera and develop a single-snapshot, single-sensor high color fidelity camera. Our camera is based on a plenoptic system with XYZ filters inserted in the pupil plane of the main lens. To achieve high color measurement precision of this system, we perform an end-to-end optimization of the system model that includes light source information, object information, optical system information, plenoptic image processing and color estimation processing. Optimized system characteristics are exploited to build an XYZ plenoptic colorimetric camera prototype that achieves high color measurement precision. We describe an application of our colorimetric camera to color shading evaluation of display and show that it achieves color accuracy of ΔE<0.01.

High signal-to-noise-ratio electro-optical terahertz imaging system based on an optical demodulating detector array.

PubMed

Spickermann, Gunnar; Friederich, Fabian; Roskos, Hartmut G; Bolívar, Peter Haring

2009-11-01

We present a 64x48 pixel 2D electro-optical terahertz (THz) imaging system using a photonic mixing device time-of-flight camera as an optical demodulating detector array. The combination of electro-optic detection with a time-of-flight camera increases sensitivity drastically, enabling the use of a nonamplified laser source for high-resolution real-time THz electro-optic imaging.

Generalized assorted pixel camera: postcapture control of resolution, dynamic range, and spectrum.

PubMed

Yasuma, Fumihito; Mitsunaga, Tomoo; Iso, Daisuke; Nayar, Shree K

2010-09-01

We propose the concept of a generalized assorted pixel (GAP) camera, which enables the user to capture a single image of a scene and, after the fact, control the tradeoff between spatial resolution, dynamic range and spectral detail. The GAP camera uses a complex array (or mosaic) of color filters. A major problem with using such an array is that the captured image is severely under-sampled for at least some of the filter types. This leads to reconstructed images with strong aliasing. We make four contributions in this paper: 1) we present a comprehensive optimization method to arrive at the spatial and spectral layout of the color filter array of a GAP camera. 2) We develop a novel algorithm for reconstructing the under-sampled channels of the image while minimizing aliasing artifacts. 3) We demonstrate how the user can capture a single image and then control the tradeoff of spatial resolution to generate a variety of images, including monochrome, high dynamic range (HDR) monochrome, RGB, HDR RGB, and multispectral images. 4) Finally, the performance of our GAP camera has been verified using extensive simulations that use multispectral images of real world scenes. A large database of these multispectral images has been made available at http://www1.cs.columbia.edu/CAVE/projects/gap_camera/ for use by the research community.

Dynamic characteristics of far-field radiation of current modulated phase-locked diode laser arrays

NASA Technical Reports Server (NTRS)

Elliott, R. A.; Hartnett, K.

1987-01-01

A versatile and powerful streak camera/frame grabber system for studying the evolution of the near and far field radiation patterns of diode lasers was assembled and tested. Software needed to analyze and display the data acquired with the steak camera/frame grabber system was written and the total package used to record and perform preliminary analyses on the behavior of two types of laser, a ten emitter gain guided array and a flared waveguide Y-coupled array. Examples of the information which can be gathered with this system are presented.

NECTAr: New electronics for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Vorobiov, S.; Bolmont, J.; Corona, P.; Delagnes, E.; Feinstein, F.; Gascón, D.; Glicenstein, J.-F.; Naumann, C. L.; Nayman, P.; Sanuy, A.; Toussenel, F.; Vincent, P.

2011-05-01

The European astroparticle physics community aims to design and build the next generation array of Imaging Atmospheric Cherenkov Telescopes (IACTs), that will benefit from the experience of the existing H.E.S.S. and MAGIC detectors, and further expand the very-high energy astronomy domain. In order to gain an order of magnitude in sensitivity in the 10 GeV to >100TeV range, the Cherenkov Telescope Array (CTA) will employ 50-100 mirrors of various sizes equipped with 1000-4000 channels per camera, to be compared with the 6000 channels of the final H.E.S.S. array. A 3-year program, started in 2009, aims to build and test a demonstrator module of a generic CTA camera. We present here the NECTAr design of front-end electronics for the CTA, adapted to the trigger and data acquisition of a large IACTs array, with simple production and maintenance. Cost and camera performances are optimized by maximizing integration of the front-end electronics (amplifiers, fast analog samplers, ADCs) in an ASIC, achieving several GS/s and a few μs readout dead-time. We present preliminary results and extrapolated performances from Monte Carlo simulations.

Space Shuttle Projects

NASA Image and Video Library

2002-03-07

STS-109 Astronaut Michael J. Massimino, mission specialist, perched on the Shuttle's robotic arm is working at the stowage area for the Hubble Space Telescope's port side solar array. Working in tandem with James. H. Newman, Massimino removed the old port solar array and stored it in Columbia's payload bay for return to Earth. The two went on to install a third generation solar array and its associated electrical components. Two crew mates had accomplished the same feat with the starboard array on the previous day. In addition to the replacement of the solar arrays, the STS-109 crew also installed the experimental cooling system for the Hubble's Near-Infrared Camera (NICMOS), replaced the power control unit (PCU), and replaced the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS). The 108th flight overall in NASA's Space Shuttle Program, the Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 for 10 days, 22 hours, and 11 minutes. Five space walks were conducted to complete the HST upgrades. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built.

Linear array of photodiodes to track a human speaker for video recording

NASA Astrophysics Data System (ADS)

DeTone, D.; Neal, H.; Lougheed, R.

2012-12-01

Communication and collaboration using stored digital media has garnered more interest by many areas of business, government and education in recent years. This is due primarily to improvements in the quality of cameras and speed of computers. An advantage of digital media is that it can serve as an effective alternative when physical interaction is not possible. Video recordings that allow for viewers to discern a presenter's facial features, lips and hand motions are more effective than videos that do not. To attain this, one must maintain a video capture in which the speaker occupies a significant portion of the captured pixels. However, camera operators are costly, and often do an imperfect job of tracking presenters in unrehearsed situations. This creates motivation for a robust, automated system that directs a video camera to follow a presenter as he or she walks anywhere in the front of a lecture hall or large conference room. Such a system is presented. The system consists of a commercial, off-the-shelf pan/tilt/zoom (PTZ) color video camera, a necklace of infrared LEDs and a linear photodiode array detector. Electronic output from the photodiode array is processed to generate the location of the LED necklace, which is worn by a human speaker. The computer controls the video camera movements to record video of the speaker. The speaker's vertical position and depth are assumed to remain relatively constant- the video camera is sent only panning (horizontal) movement commands. The LED necklace is flashed at 70Hz at a 50% duty cycle to provide noise-filtering capability. The benefit to using a photodiode array versus a standard video camera is its higher frame rate (4kHz vs. 60Hz). The higher frame rate allows for the filtering of infrared noise such as sunlight and indoor lighting-a capability absent from other tracking technologies. The system has been tested in a large lecture hall and is shown to be effective.

Performance verification of the FlashCam prototype camera for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Werner, F.; Bauer, C.; Bernhard, S.; Capasso, M.; Diebold, S.; Eisenkolb, F.; Eschbach, S.; Florin, D.; Föhr, C.; Funk, S.; Gadola, A.; Garrecht, F.; Hermann, G.; Jung, I.; Kalekin, O.; Kalkuhl, C.; Kasperek, J.; Kihm, T.; Lahmann, R.; Marszalek, A.; Pfeifer, M.; Principe, G.; Pühlhofer, G.; Pürckhauer, S.; Rajda, P. J.; Reimer, O.; Santangelo, A.; Schanz, T.; Schwab, T.; Steiner, S.; Straumann, U.; Tenzer, C.; Vollhardt, A.; Wolf, D.; Zietara, K.; CTA Consortium

2017-12-01

The Cherenkov Telescope Array (CTA) is a future gamma-ray observatory that is planned to significantly improve upon the sensitivity and precision of the current generation of Cherenkov telescopes. The observatory will consist of several dozens of telescopes with different sizes and equipped with different types of cameras. Of these, the FlashCam camera system is the first to implement a fully digital signal processing chain which allows for a traceable, configurable trigger scheme and flexible signal reconstruction. As of autumn 2016, a prototype FlashCam camera for the medium-sized telescopes of CTA nears completion. First results of the ongoing system tests demonstrate that the signal chain and the readout system surpass CTA requirements. The stability of the system is shown using long-term temperature cycling.

Infrared Luminosities and Dust Properties of z ≈ 2 Dust-obscured Galaxies

NASA Astrophysics Data System (ADS)

Bussmann, R. S.; Dey, Arjun; Borys, C.; Desai, V.; Jannuzi, B. T.; Le Floc'h, E.; Melbourne, J.; Sheth, K.; Soifer, B. T.

2009-11-01

We present SHARC-II 350 μm imaging of twelve 24 μm bright (F 24 μm > 0.8 mJy) Dust-Obscured Galaxies (DOGs) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) 1 mm imaging of a subset of two DOGs. These objects are selected from the Boötes field of the NOAO Deep Wide-Field Survey. Detections of four DOGs at 350 μm imply infrared (IR) luminosities which are consistent to within a factor of 2 of expectations based on a warm-dust spectral energy distribution (SED) scaled to the observed 24 μm flux density. The 350 μm upper limits for the 8 non-detected DOGs are consistent with both Mrk 231 and M82 (warm-dust SEDs), but exclude cold dust (Arp 220) SEDs. The two DOGs targeted at 1 mm were not detected in our CARMA observations, placing strong constraints on the dust temperature: T dust > 35-60 K. Assuming these dust properties apply to the entire sample, we find dust masses of ≈3 × 108 M sun. In comparison to other dusty z ~ 2 galaxy populations such as submillimeter galaxies (SMGs) and other Spitzer-selected high-redshift sources, this sample of DOGs has higher IR luminosities (2 × 1013 L sun versus 6 × 1012 L sun for the other galaxy populations) that are driven by warmer dust temperatures (>35-60 K versus ~30 K) and lower inferred dust masses (3 × 108 M sun versus 3 × 109 M sun). Wide-field Herschel and Submillimeter Common-User Bolometer Array-2 surveys should be able to detect hundreds of these power-law-dominated DOGs. We use the existing Hubble Space Telescope and Spitzer/InfraRed Array Camera data to estimate stellar masses of these sources and find that the stellar to gas mass ratio may be higher in our 24 μm bright sample of DOGs than in SMGs and other Spitzer-selected sources. Although much larger sample sizes are needed to provide a definitive conclusion, the data are consistent with an evolutionary trend in which the formation of massive galaxies at z ~ 2 involves a submillimeter bright, cold-dust, and star-formation-dominated phase followed by a 24 μm bright, warm-dust and AGN-dominated phase.

Fabrication of an Aluminum Based Hot Electron Mixer for Terahertz Applications

NASA Technical Reports Server (NTRS)

Echternach, P. M.; LeDuc, H. G.; Skalare, A.; McGrath, W. R.

2000-01-01

Aluminum based diffusion cooled hot electron bolometers (HEB) mixers, predicted to have better noise, bandwidth and to require less LO power than Nb based diffusion cooled HEBs, have been fabricated. Preliminary DC tests were performed. The bolometer elements consisted of short (0.1 to 0.3 micron), narrow (0.08 to 0. 15 micron) and thin (11 nm) aluminum wires connected to large contact pads consisting of a novel trilayer Al/Ti/Au. The patterns were defined by electron beam lithography and the metal deposition involved a double angle process, the Aluminum wires being deposited straight on and the pads being deposited at a 45 degree angle without breaking vacuum. The Al/Ti/Au trilayer was developed to provide a way of making contact between the aluminum wire and the gold antenna. The Titanium layer acts as a diffusion barrier to avoid damage of the Aluminum contact and bolometer wire and to lower the transition temperature of the pads to below that of the bolometer wire. The Au layer avoids the formation of an oxide on the Ti layer and provides good electrical contact to the IF/antenna structure. The resistance of the bolometers as a function of temperature was measured. It is clear that below the transition temperature of the wire (1.8K) but above the transition temperature of the contact pads (0.6K), the proximity effect drives most of the bolometer wire normal, causing a very broad transition. This effect should not affect the performance of the bolometers since they will be operated at a temperature below the TC of the pads. This is evident from the IV characteristics measured at 0.3K. RF characterization tests will begin shortly.

Analysis of the calibration methods and error propagation for the sensitivity S and the cooling time constant τc of the gold metal foil bolometers

NASA Astrophysics Data System (ADS)

Murari, A.; Cecconello, M.; Marrelli, L.; Mast, K. F.

2004-08-01

Bolometers are radiation sensors designed to have a spectral response as constant as possible in the region of interest. In high-temperature plasmas, the main radiation output is in the ultraviolet and SXR part of the spectrum and the metal foil bolometers are special detectors developed for this interval. For such sensors, as in general for all bolometers, the absolute calibration is a crucial issue. This problem becomes particularly severe when, like in nuclear fusion, the sensors are not easily accessible. In this article, a detailed description of the in situ calibration methods for the bolometer sensitivity S and the cooling time τc, the two essential parameters characterizing the behavior of the sensor, is provided and an estimate of the uncertainties for both constants is presented. The sensitivity S is determined via an electrical calibration, in which the effect of the cables connecting the bolometers to the powering circuitry is taken into account leading to an effective estimate for S. Experimental measurements confirming the quality of the adopted coaxial cable modelling are reported. The cooling time constant τc is calculated via an optical calibration, in which the bolometer is stimulated by a light-emitting diode. The behavior of τc in a broad pressure range is investigated, showing that it does not depend upon this quantity up until 10-2 mbar, well above the standard operating conditions of many applications. The described methods were tested on 36 bolometric channels of RFX tomography, providing a significant statistical basis for present applications and future developments of both the calibration procedures and the detectors.

Building the analytical response in frequency domain of AC biased bolometers. Application to Planck/HFI

NASA Astrophysics Data System (ADS)

Sauvé, Alexandre; Montier, Ludovic

2016-12-01

Context: Bolometers are high sensitivity detector commonly used in Infrared astronomy. The HFI instrument of the Planck satellite makes extensive use of them, but after the satellite launch two electronic related problems revealed critical. First an unexpected excess response of detectors at low optical excitation frequency for ν < 1 Hz, and secondly the Analog To digital Converter (ADC) component had been insufficiently characterized on-ground. These two problems require an exquisite knowledge of detector response. However bolometers have highly nonlinear characteristics, coming from their electrical and thermal coupling making them very difficult to model. Goal: We present a method to build the analytical transfer function in frequency domain which describe the voltage response of an Alternative Current (AC) biased bolometer to optical excitation, based on the standard bolometer model. This model is built using the setup of the Planck/HFI instrument and offers the major improvement of being based on a physical model rather than the currently in use had-hoc model based on Direct Current (DC) bolometer theory. Method: The analytical transfer function expression will be presented in matrix form. For this purpose, we build linearized versions of the bolometer electro thermal equilibrium. A custom description of signals in frequency is used to solve the problem with linear algebra. The model performances is validated using time domain simulations. Results: The provided expression is suitable for calibration and data processing. It can also be used to provide constraints for fitting optical transfer function using real data from steady state electronic response and optical response. The accurate description of electronic response can also be used to improve the ADC nonlinearity correction for quickly varying optical signals.

Approaches on calibration of bolometer and establishment of bolometer calibration device

NASA Astrophysics Data System (ADS)

Xia, Ming; Gao, Jianqiang; Ye, Jun'an; Xia, Junwen; Yin, Dejin; Li, Tiecheng; Zhang, Dong

2015-10-01

Bolometer is mainly used for measuring thermal radiation in the field of public places, labor hygiene, heating and ventilation and building energy conservation. The working principle of bolometer is under the exposure of thermal radiation, temperature of black absorbing layer of detector rise after absorption of thermal radiation, which makes the electromotive force produced by thermoelectric. The white light reflective layer of detector does not absorb thermal radiation, so the electromotive force produced by thermoelectric is almost zero. A comparison of electromotive force produced by thermoelectric of black absorbing layer and white reflective layer can eliminate the influence of electric potential produced by the basal background temperature change. After the electromotive force which produced by thermal radiation is processed by the signal processing unit, the indication displays through the indication display unit. The measurement unit of thermal radiation intensity is usually W/m2 or kW/m2. Its accurate and reliable value has important significance for high temperature operation, labor safety and hygiene grading management. Bolometer calibration device is mainly composed of absolute radiometer, the reference light source, electric measuring instrument. Absolute radiometer is a self-calibration type radiometer. Its working principle is using the electric power which can be accurately measured replaces radiation power to absolutely measure the radiation power. Absolute radiometer is the standard apparatus of laser low power standard device, the measurement traceability is guaranteed. Using the calibration method of comparison, the absolute radiometer and bolometer measure the reference light source in the same position alternately which can get correction factor of irradiance indication. This paper is mainly about the design and calibration method of the bolometer calibration device. The uncertainty of the calibration result is also evaluated.

Progress in passive submillimeter-wave video imaging

NASA Astrophysics Data System (ADS)

Heinz, Erik; May, Torsten; Born, Detlef; Zieger, Gabriel; Peiselt, Katja; Zakosarenko, Vyacheslav; Krause, Torsten; Krüger, André; Schulz, Marco; Bauer, Frank; Meyer, Hans-Georg

2014-06-01

Since 2007 we are developing passive submillimeter-wave video cameras for personal security screening. In contradiction to established portal-based millimeter-wave scanning techniques, these are suitable for stand-off or stealth operation. The cameras operate in the 350GHz band and use arrays of superconducting transition-edge sensors (TES), reflector optics, and opto-mechanical scanners. Whereas the basic principle of these devices remains unchanged, there has been a continuous development of the technical details, as the detector array, the scanning scheme, and the readout, as well as system integration and performance. The latest prototype of this camera development features a linear array of 128 detectors and a linear scanner capable of 25Hz frame rate. Using different types of reflector optics, a field of view of 1×2m2 and a spatial resolution of 1-2 cm is provided at object distances of about 5-25m. We present the concept of this camera and give details on system design and performance. Demonstration videos show its capability for hidden threat detection and illustrate possible application scenarios.

IR detector system based on high-Tc superconducting bolometer on SI membrane

NASA Astrophysics Data System (ADS)

Burnus, M.; Hefle, G.; Heidenblut, T.; Khrebtov, Igor A.; Laukemper, J.; Michalke, W.; Neff, H.; Schwierzi, B.; Semtchinova, O. K.; Steinbeiss, E.; Tkachenko, A. D.

1996-06-01

An infrared detector system based on high-T(subscript c) superconducting (HTS) membrane bolometer is reported. Superconducting transition-edge bolometer has been manufactured by silicon micromachining using an epitaxial GdBa(subscript 2)Cu(subscript 3)O(subscript 7-x) film on an epitaxial yttria- stabilized zirconia buffer layer on silicon. The active area of the element is 0.85 X 0.85 mm(superscript 2). The membrane thickness is 1 micrometers , those of the buffer layer and HTS films are 50 nm. The detectivity of bolometer, D(superscript *), is 3.8 X 10(superscript 9) cm Hz(superscript 1/2) W(superscript -1) at 84.5 K and within the frequency regime 100 < f < 300 Hz. The optical response is 580 V/W at time constant 0.4 ms. This is one of the fastest composite type HTS-bolometer ever reported. The bolometer is mounted on a metal N(subscript 2)-liquid cryostat, which fits the preamplifier. With the volume of N(subscript 2)-reservoir being 0.1 liter, the cryostat holds nitrogen for about 8 hours. Using only wire heater with constant current, the temperature stability of about 0.03 K/h is achieved. The detector system can be used in IR- Fourier spectroscopy at wavelengths longer than the typical operating range of semiconductor detectors (wavelength greater than about 20 micrometers ).

Vision Aided Inertial Navigation System Augmented with a Coded Aperture

DTIC Science & Technology

2011-03-24

as the change in blur at different distances from the pixel plane can be inferred. Cameras with a micro lens array (called plenoptic cameras...images from 8 slightly different perspectives [14,43]. Dappled photography is a similar to the plenoptic camera approach except that a cosine mask

Theory of noise equivalent power of a high-temperature superconductor far-infrared bolometer in a photo-thermoelectrical mode of operation

NASA Astrophysics Data System (ADS)

Kaila, M. M.; Russell, G. J.

2000-12-01

We present a theory of noise equivalent power (NEP) and related parameters for a high-temperature superconductor (HTSC) bolometer in which temperature and resistance are the noise sources for open circuit operation and phonon and resistance are the noise sources for voltage-biased operation of the bolometer. The bolometer is designed to use a photo-thermoelectrical mode of operation. A mathematical formulation for the open circuit operation is first presented followed by an analysis of the heterodyne case with a bias applied in constant voltage mode. For the first time electrothermal (ET) and thermoelectrical (TE) feedback are treated in the heat balance equation simultaneously. A parallel resistance geometry consisting of thermoelectric and HTSC material legs has been chosen for the device. Computations for the ET-TE feedback show that the response time improves by three orders of magnitude and the responsivity becomes double for the same TE feedback. In the heat balance equation we have included among the heat transfer processes the temperature dependence of the thermal conductance at the bolometer-substrate interface for the dynamic state.

The GCT camera for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Lapington, J. S.; Abchiche, A.; Allan, D.; Amans, J.-P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Bose, R.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Buckley, J.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dournaux, J.-L.; Dumas, D.; Ernenwein, J.-P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J.-M.; Jankowsky, D.; Jegouzo, I.; Jogler, T.; Kawashima, T.; Kraus, M.; Laporte, P.; Leach, S.; Lefaucheur, J.; Markoff, S.; Melse, T.; Minaya, I. A.; Mohrmann, L.; Molyneux, P.; Moore, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayede, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Varner, G.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.; Zorn, J.; CTA Consortium

2017-12-01

The Gamma Cherenkov Telescope (GCT) is one of the designs proposed for the Small Sized Telescope (SST) section of the Cherenkov Telescope Array (CTA). The GCT uses dual-mirror optics, resulting in a compact telescope with good image quality and a large field of view with a smaller, more economical, camera than is achievable with conventional single mirror solutions. The photon counting GCT camera is designed to record the flashes of atmospheric Cherenkov light from gamma and cosmic ray initiated cascades, which last only a few tens of nanoseconds. The GCT optics require that the camera detectors follow a convex surface with a radius of curvature of 1 m and a diameter of 35 cm, which is approximated by tiling the focal plane with 32 modules. The first camera prototype is equipped with multi-anode photomultipliers, each comprising an 8×8 array of 6×6 mm2 pixels to provide the required angular scale, adding up to 2048 pixels in total. Detector signals are shaped, amplified and digitised by electronics based on custom ASICs that provide digitisation at 1 GSample/s. The camera is self-triggering, retaining images where the focal plane light distribution matches predefined spatial and temporal criteria. The electronics are housed in the liquid-cooled, sealed camera enclosure. LED flashers at the corners of the focal plane provide a calibration source via reflection from the secondary mirror. The first GCT camera prototype underwent preliminary laboratory tests last year. In November 2015, the camera was installed on a prototype GCT telescope (SST-GATE) in Paris and was used to successfully record the first Cherenkov light of any CTA prototype, and the first Cherenkov light seen with such a dual-mirror optical system. A second full-camera prototype based on Silicon Photomultipliers is under construction. Up to 35 GCTs are envisaged for CTA.

Next generation miniature simultaneous multi-hyperspectral imaging systems

NASA Astrophysics Data System (ADS)

Hinnrichs, Michele; Gupta, Neelam

2014-03-01

The concept for a hyperspectral imaging system using a Fabry-Perot tunable filter (FPTF) array that is fabricated using "miniature optical electrical mechanical system" (MOEMS) technology. [1] Using an array of FPTF as an approach to hyperspectral imaging relaxes wavelength tuning requirements considerably because of the reduced portion of the spectrum that is covered by each element in the array. In this paper, Pacific Advanced Technology and ARL present the results of a concept design and performed analysis of a MOEMS based tunable Fabry-Perot array (FPTF) to perform simultaneous multispectral and hyperspectral imaging with relatively high spatial resolution. The concept design was developed with support of an Army SBIR Phase I program The Fabry-Perot tunable MOEMS filter array was combined with a miniature optics array and a focal plane array of 1024 x 1024 pixels to produce 16 colors every frame of the camera. Each color image has a spatial resolution of 256 x 256 pixels with an IFOV of 1.7 mrads and FOV of 25 degrees. The spectral images are collected simultaneously allowing high resolution spectral-spatial-temporal information in each frame of the camera, thus enabling the implementation of spectral-temporal-spatial algorithms in real-time to provide high sensitivity for the detection of weak signals in a high clutter background environment with low sensitivity to camera motion. The challenge in the design was the independent actuation of each Fabry Perot element in the array allowing for individual tuning. An additional challenge was the need to maximize the fill factor to improve the spatial coverage with minimal dead space. This paper will only address the concept design and analysis of the Fabry-Perot tunable filter array. A previous paper presented at SPIE DSS in 2012 explained the design of the optical array.

Method for determining and displaying the spacial distribution of a spectral pattern of received light

DOEpatents

Bennett, Charles L.

1996-01-01

An imaging Fourier transform spectrometer (10, 210) having a Fourier transform infrared spectrometer (12) providing a series of images (40) to a focal plane array camera (38). The focal plane array camera (38) is clocked to a multiple of zero crossing occurrences as caused by a moving mirror (18) of the Fourier transform infrared spectrometer (12) and as detected by a laser detector (50) such that the frame capture rate of the focal plane array camera (38) corresponds to a multiple of the zero crossing rate of the Fourier transform infrared spectrometer (12). The images (40) are transmitted to a computer (45) for processing such that representations of the images (40) as viewed in the light of an arbitrary spectral "fingerprint" pattern can be displayed on a monitor (60) or otherwise stored and manipulated by the computer (45).

High energy X-ray pinhole imaging at the Z facility

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

McPherson, L. Armon; Ampleford, David J.; Coverdale, Christine A.

A new high photon energy (hv > 15 keV) time-integrated pinhole camera (TIPC) has become available at the Z facility for diagnostic applications. This camera employs five pinholes in a linear array for recording five images at once onto an image plate detector. Each pinhole may be independently filtered to yield five different spectral responses. The pinhole array is fabricated from a 1-cm thick tungsten block and is available with either straight pinholes or conical pinholes. Each pinhole within the array block is 250 μm in diameter. The five pinholes are splayed with respect to each other such that theymore » point to the same location in space, and hence present the same view of the target load at the Z facility. The fielding distance is 66 cm and the nominal image magnification is 0.374. Initial experimental results are shown to illustrate the performance of the camera.« less

The CAOS camera platform: ushering in a paradigm change in extreme dynamic range imager design

NASA Astrophysics Data System (ADS)

Riza, Nabeel A.

2017-02-01

Multi-pixel imaging devices such as CCD, CMOS and Focal Plane Array (FPA) photo-sensors dominate the imaging world. These Photo-Detector Array (PDA) devices certainly have their merits including increasingly high pixel counts and shrinking pixel sizes, nevertheless, they are also being hampered by limitations in instantaneous dynamic range, inter-pixel crosstalk, quantum full well capacity, signal-to-noise ratio, sensitivity, spectral flexibility, and in some cases, imager response time. Recently invented is the Coded Access Optical Sensor (CAOS) Camera platform that works in unison with current Photo-Detector Array (PDA) technology to counter fundamental limitations of PDA-based imagers while providing high enough imaging spatial resolution and pixel counts. Using for example the Texas Instruments (TI) Digital Micromirror Device (DMD) to engineer the CAOS camera platform, ushered in is a paradigm change in advanced imager design, particularly for extreme dynamic range applications.

GPU-based real-time trinocular stereo vision

NASA Astrophysics Data System (ADS)

Yao, Yuanbin; Linton, R. J.; Padir, Taskin

2013-01-01

Most stereovision applications are binocular which uses information from a 2-camera array to perform stereo matching and compute the depth image. Trinocular stereovision with a 3-camera array has been proved to provide higher accuracy in stereo matching which could benefit applications like distance finding, object recognition, and detection. This paper presents a real-time stereovision algorithm implemented on a GPGPU (General-purpose graphics processing unit) using a trinocular stereovision camera array. Algorithm employs a winner-take-all method applied to perform fusion of disparities in different directions following various image processing techniques to obtain the depth information. The goal of the algorithm is to achieve real-time processing speed with the help of a GPGPU involving the use of Open Source Computer Vision Library (OpenCV) in C++ and NVidia CUDA GPGPU Solution. The results are compared in accuracy and speed to verify the improvement.

High energy X-ray pinhole imaging at the Z facility

DOE PAGES

McPherson, L. Armon; Ampleford, David J.; Coverdale, Christine A.; ...

2016-06-06

A new high photon energy (hv > 15 keV) time-integrated pinhole camera (TIPC) has become available at the Z facility for diagnostic applications. This camera employs five pinholes in a linear array for recording five images at once onto an image plate detector. Each pinhole may be independently filtered to yield five different spectral responses. The pinhole array is fabricated from a 1-cm thick tungsten block and is available with either straight pinholes or conical pinholes. Each pinhole within the array block is 250 μm in diameter. The five pinholes are splayed with respect to each other such that theymore » point to the same location in space, and hence present the same view of the target load at the Z facility. The fielding distance is 66 cm and the nominal image magnification is 0.374. Initial experimental results are shown to illustrate the performance of the camera.« less

Design of an adiabatic demagnetization refrigerator for studies in astrophysics

NASA Technical Reports Server (NTRS)

Castles, S.

1983-01-01

An adiabatic demagnetization refrigerator was designed for cooling infrared bolometers for studies in astrophysics and aeronomy. The design was tailored to the requirements of a Shuttle sortie experiment. The refrigerator should be capable of maintaining three bolometers at 0.1 K with a 90% cycle. The advantage are of operations the bolometer at 0.1K. greater sensitivity, faster response time, and the ability to use larger bolometer elements without compromising the response time. The design presented is the first complete design of an ADR intended for use in space. The most important of these specifications are to survive a Shuttle launch, to operate with 1.5 K - 2.0 K space-pumped liquid helium as a heat sink, to have a 90% duty cycle, and to be highly efficient.

An image-based array trigger for imaging atmospheric Cherenkov telescope arrays

NASA Astrophysics Data System (ADS)

Dickinson, Hugh; Krennrich, Frank; Weinstein, Amanda; Eisch, Jonathan; Byrum, Karen; Anderson, John; Drake, Gary

2018-05-01

It is anticipated that forthcoming, next generation, atmospheric Cherenkov telescope arrays will include a number of medium-sized telescopes that are constructed using a dual-mirror Schwarzschild-Couder configuration. These telescopes will sample a wide (8 °) field of view using a densely pixelated camera comprising over 104 individual readout channels. A readout frequency congruent with the expected single-telescope trigger rates would result in substantial data rates. To ameliorate these data rates, a novel, hardware-level Distributed Intelligent Array Trigger (DIAT) is envisioned. A copy of the DIAT operates autonomously at each telescope and uses reduced resolution imaging data from a limited subset of nearby telescopes to veto events prior to camera readout and any subsequent network transmission of camera data that is required for centralized storage or aggregation. We present the results of Monte-Carlo simulations that evaluate the efficacy of a "Parallax width" discriminator that can be used by the DIAT to efficiently distinguish between genuine gamma-ray initiated events and unwanted background events that are initiated by hadronic cosmic rays.

High Tc bolometer developments for planetary missions

NASA Technical Reports Server (NTRS)

Brasunas, J.; Lakew, B.

1991-01-01

A simple polishing technique was developed for thinning the LaAlO3 substrates for high-quality Tc bolometer films, and thus reducing their heat capacity. A 150-ms bolometer was made on a LaAlO3 substrate with a 5-Hz D* value of 1.5 x 10 exp 8. It is shown that passive temperature stabilization is adequate for operation at the transition. There remained excess noise at the transition, but this noise appears to be of nonbolometric origin.

Fabrication of Monolithic Sapphire Membranes for High Tc Bolometer Array Development

NASA Technical Reports Server (NTRS)

Pugel, D. E.; Lakew, B.; Aslam, S.; Wang, L.

2003-01-01

This paper examines the effectiveness of Pt/Cr thin film masks for the architecture of monolithic membrane structures in r-plane sapphire. The development of a pinhole-free Pt/Cr composite mask that is resistant to hot H2SO4:H3PO4 etchant, will lead to the fabrication of smooth sapphire membranes whose surfaces are well-suited for the growth of low-noise high Tc films. In particular, the relationship of thermal annealing conditions on the Pt/Cr composite mask system to: (1) changes in the surface morphology and elemental concentration of the Pt/Cr thin film layers and (2) etch pit formation on the sapphire surface will be presented.

Infrared Astronomy

NASA Astrophysics Data System (ADS)

Grygar, J.

2018-04-01

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

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-04

S61-E-002 (4 Dec 1993) --- This view, backdropped against the blackness of space shows one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST). The scene was photographed from inside Endeavour's cabin with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. This view features the minus V-2 panel. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-04

S61-E-003 (4 Dec 1993) --- This medium close-up view of one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. This view shows the cell side of the minus V-2 panel. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

Methods for identification of images acquired with digital cameras

NASA Astrophysics Data System (ADS)

Geradts, Zeno J.; Bijhold, Jurrien; Kieft, Martijn; Kurosawa, Kenji; Kuroki, Kenro; Saitoh, Naoki

2001-02-01

From the court we were asked whether it is possible to determine if an image has been made with a specific digital camera. This question has to be answered in child pornography cases, where evidence is needed that a certain picture has been made with a specific camera. We have looked into different methods of examining the cameras to determine if a specific image has been made with a camera: defects in CCDs, file formats that are used, noise introduced by the pixel arrays and watermarking in images used by the camera manufacturer.

Status of a Novel 4-Band Submm/mm Camera for the Caltech Submillimeter Observatory

NASA Astrophysics Data System (ADS)

Noroozian, Omid; Day, P.; Glenn, J.; Golwala, S.; Kumar, S.; LeDuc, H. G.; Mazin, B.; Nguyen, H. T.; Schlaerth, J.; Vaillancourt, J. E.; Vayonakis, A.; Zmuidzinas, J.

2007-12-01

Submillimeter observations are important to the understanding of galaxy formation and evolution. Determination of the spectral energy distribution in the millimeter and submillimeter regimes allows important and powerful diagnostics. To this end, we are undertaking the construction of a 4-band (750, 850, 1100, 1300 microns) 8-arcminute field of view camera for the Caltech Submillimeter Observatory. The focal plane will make use of three novel technologies: photolithographic phased array antennae, on-chip band-pass filters, and microwave kinetic inductance detectors (MKID). The phased array antenna design obviates beam-defining feed horns. On-chip band-pass filters eliminate band-defining metal-mesh filters. Together, the antennae and filters enable each spatial pixel to observe in all four bands simultaneously. MKIDs are highly multiplexable background-limited photon detectors. Readout of the MKID array will be done with software-defined radio (See poster by Max-Moerbeck et al.). This camera will provide an order-of-magnitude larger mapping speed than existing instruments and will be comparable to SCUBA 2 in terms of the detection rate for dusty sources, but complementary to SCUBA 2 in terms of wavelength coverage. We present results from an engineering run with a demonstration array, the baseline design for the science array, and the status of instrument design, construction, and testing. We anticipate the camera will be available at the CSO in 2010. This work has been supported by NASA ROSES APRA grants NNG06GG16G and NNG06GC71G, the NASA JPL Research and Technology Development Program, and the Gordon and Betty Moore Foundation.

The initial design of LAPAN's IR micro bolometer using mission analysis process

NASA Astrophysics Data System (ADS)

Bustanul, A.; Irwan, P.; M. T., Andi; Firman, B.

2016-11-01

As new player in Infra Red (IR) sector, uncooled, small, and lightweight IR Micro Bolometer has been chosen as one of payloads for LAPAN's next micro satellite project. Driven the desire to create our own IR Micro Bolometer, mission analysis design procedure has been applied. After tracing all possible missions, the Planck's and Wien's Law for black body, Temperature Responsivity (TR), and sub-pixel response had been utilized in order to determine the appropriate spectral radiance. The 3.8 - 4 μm wavelength were available to detect wild fire (forest fire) and active volcanoes, two major problems faced by Indonesia. In order to strengthen and broaden the result, iteration process had been used throughout the process. The analysis, then, were continued by calculating Ground pixel size, IFOV pixel, swath width, and focus length. Meanwhile, regarding of resolution, at least it is 400 m. The further procedure covered the integrated of optical design, wherein we combined among optical design software, Zemax, with mechanical analysis software (structure and thermal analysis), such as Nastran and Thermal Desktop / Sinda Fluint. The integration process was intended to produce high performance optical system of our IR Micro Bolometer that can be used under extreme environment. The results of all those analysis, either in graphs or in measurement, show that the initial design of LAPAN'S IR Micro Bolometer meets the determined requirement. However, it needs the further evaluation (iteration). This paper describes the initial design of LAPAN's IR Micro Bolometer using mission analysis process

Phase and amplitude wave front sensing and reconstruction with a modified plenoptic camera

NASA Astrophysics Data System (ADS)

Wu, Chensheng; Ko, Jonathan; Nelson, William; Davis, Christopher C.

2014-10-01

A plenoptic camera is a camera that can retrieve the direction and intensity distribution of light rays collected by the camera and allows for multiple reconstruction functions such as: refocusing at a different depth, and for 3D microscopy. Its principle is to add a micro-lens array to a traditional high-resolution camera to form a semi-camera array that preserves redundant intensity distributions of the light field and facilitates back-tracing of rays through geometric knowledge of its optical components. Though designed to process incoherent images, we found that the plenoptic camera shows high potential in solving coherent illumination cases such as sensing both the amplitude and phase information of a distorted laser beam. Based on our earlier introduction of a prototype modified plenoptic camera, we have developed the complete algorithm to reconstruct the wavefront of the incident light field. In this paper the algorithm and experimental results will be demonstrated, and an improved version of this modified plenoptic camera will be discussed. As a result, our modified plenoptic camera can serve as an advanced wavefront sensor compared with traditional Shack- Hartmann sensors in handling complicated cases such as coherent illumination in strong turbulence where interference and discontinuity of wavefronts is common. Especially in wave propagation through atmospheric turbulence, this camera should provide a much more precise description of the light field, which would guide systems in adaptive optics to make intelligent analysis and corrections.

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

NASA Astrophysics Data System (ADS)

Ferkinhoff, Carl; Nikola, Thomas; Parshley, Stephen C.; Stacey, Gordon J.; Irwin, Kent D.; Cho, Hsiao-Mei; Halpern, Mark

2010-07-01

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 JCMT.

Sn nanothreads in GaAs: experiment and simulation

NASA Astrophysics Data System (ADS)

Semenikhin, I.; Vyurkov, V.; Bugaev, A.; Khabibullin, R.; Ponomarev, D.; Yachmenev, A.; Maltsev, P.; Ryzhii, M.; Otsuji, T.; Ryzhii, V.

2016-12-01

The gated GaAs structures like the field-effect transistor with the array of the Sn nanothreads was fabricated via delta-doping of vicinal GaAs surface by Sn atoms with a subsequent regrowth. That results in the formation of the chains of Sn atoms at the terrace edges. Two device models were developed. The quantum model accounts for the quantization of the electron energy spectrum in the self-consistent two-dimensional electric potential, herewith the electron density distribution in nanothread arrays for different gate voltages is calculated. The classical model ignores the quantization and electrons are distributed in space according to 3D density of states and Fermi-Dirac statistics. It turned out that qualitatively both models demonstrate similar behavior, nevertheless, the classical one is in better quantitative agreement with experimental data. Plausibly, the quantization could be ignored because Sn atoms are randomly placed along the thread axis. The terahertz hot-electron bolometers (HEBs) could be based on the structure under consideration.

KSC-01pp1802

NASA Image and Video Library

2001-12-01

KENNEDY SPACE CENTER, Fla. - STS-109 Mission Specialist Richard Lennehan (left) and Payload Commander John Grunsfeld get a feel for tools and equipment that will be used on the mission. The crew is at KSC to take part in Crew Equipment Interface Test activities that include familiarization with the orbiter and equipment. The goal of the mission is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the Advanced Camera for Surveys, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

Model of an optical system's influence on sensitivity of microbolometric focal plane array

NASA Astrophysics Data System (ADS)

Gogler, Sławomir; Bieszczad, Grzegorz; Zarzycka, Alicja; Szymańska, Magdalena; Sosnowski, Tomasz

2012-10-01

Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. The detectors used in thermal camera are illuminated by infrared radiation transmitted through a specialized optical system. Each optical system used influences irradiation distribution across an sensor array. In the article a model describing irradiation distribution across an array sensor working with an optical system used in the calibration set-up has been proposed. In the said method optical and geometrical considerations of the array set-up have been taken into account. By means of Monte-Carlo simulation, large number of rays has been traced to the sensor plane, what allowed to determine the irradiation distribution across the image plane for different aperture limiting configurations. Simulated results have been confronted with proposed analytical expression. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.

Preliminary performance measurements of bolometers for the planck high frequency instrument

NASA Technical Reports Server (NTRS)

Holmes, W.; Bock, J.; Ganga, K.; Hristov, V. V.; Hustead, L.; Koch, T.; Lange, A. E.; Paine, C.; Yun, M.

2002-01-01

We report on the characterization of bolometers fabricated at the Jet Propulsion Laboratory for the High Frequency Instrument (HFI) of the joint ESA/NASA Herschel/Planck mission to be launched in 2007.

The Front-End System For MARE In Milano

NASA Astrophysics Data System (ADS)

Arnaboldi, Claudio; Pessina, Gianluigi

2009-12-01

The first phase of MARE consists of 72 μ-bolometers composed each of a crystal of AgReO4 readout by Si thermistors. The spread in the thermistor characteristics and bolometer thermal coupling leads to different energy conversion gains and optimum operating points of the detectors. Detector biasing levels and voltage gains are completely remote-adjustable by the front end system developed, the subject of this paper, achieving the same signal range at the input of the DAQ system. The front end consists of a cold buffer stage, a second pseudo differential stage followed by a gain stage, an antialiasing filter, and a battery powered detector biasing set up. The DAQ system can be used to set all necessary parameters of the electronics remotely, by writing to a μ-controller located on each board. Fiber optics are used for the serial communication between the DAQ and the front end. To suppress interference noise during normal operation, the clocked devices of the front end are maintained in sleep-mode, except during the set-up phase of the experiment. An automatic DC detector characterization procedure is used to establish the optimum operating point of every detector of the array. A very low noise level has been achieved: about 3nV/□Hz at 1 Hz and 1 nV/□Hz for the white component, high frequencies.

The LUCIFER Project: Achievements and Near Future Prospects

NASA Astrophysics Data System (ADS)

Beeman, J. W.; Bellini, F.; Benetti, P.; Cardani, L.; Casali, N.; Chiesa, D.; Clemenza, M.; Dafinei, I.; Di Domizio, S.; Ferroni, F.; Gironi, L.; Giuliani, A.; Gotti, C.; Maino, M.; Nagorny, S. S.; Nisi, S.; Nones, C.; Pagnanini, L.; Pattavina, L.; Pessina, G.; Piperno, G.; Pirro, S.; Previtali, E.; Rusconi, C.; Schäffner, K.; Tomei, C.; Vignati, M.

2016-08-01

In the view of exploring the inverted hierarchy region future experiments investigating the neutrinoless double beta decay have to demand for detectors with excellent energy resolution and zero background in the energy region of interest. Cryogenic scintillating bolometers are very suitable detectors for this task since they provide particle discrimination: the simultaneous detection of the phonon and light signal allows us to identify the interacting type of particle and thus guarantees a suppression of α -induced backgrounds, the key-issue for next-generation tonne-scale bolometric experiments. The LUCIFER project aims at running the first array of enriched scintillating Zn^{ {82}}Se bolometers (total mass of about 8kg of ^{ {82}}Se) with a background level as low as 10^{ {-3}} counts/(keV kg y) in the energy region of interest. The main effort is currently focused on the finalization of the crystal growth procedure in order to achieve high quality Zn^{ {82}}Se crystals both in terms of radiopurity and bolometric properties. We present results from tests of such crystals operated at mK temperatures which demonstrate the excellent background rejection capabilities of this detection approach towards a background-free demonstrator experiment. Besides, the high purity of the enriched ^{ {82}}Se material allows us to establish the most stringent limits on the half-life of the double beta decay of ^{ {82}}Se on excited levels.

Space infrared telescope facility wide field and diffraction limited array camera (IRAC)

NASA Technical Reports Server (NTRS)

Fazio, Giovanni G.

1988-01-01

The wide-field and diffraction limited array camera (IRAC) is capable of two-dimensional photometry in either a wide-field or diffraction-limited mode over the wavelength range from 2 to 30 microns with a possible extension to 120 microns. A low-doped indium antimonide detector was developed for 1.8 to 5.0 microns, detectors were tested and optimized for the entire 1.8 to 30 micron range, beamsplitters were developed and tested for the 1.8 to 30 micron range, and tradeoff studies of the camera's optical system performed. Data are presented on the performance of InSb, Si:In, Si:Ga, and Si:Sb array detectors bumpbonded to a multiplexed CMOS readout chip of the source-follower type at SIRTF operating backgrounds (equal to or less than 1 x 10 to the 8th ph/sq cm/sec) and temperature (4 to 12 K). Some results at higher temperatures are also presented for comparison to SIRTF temperature results. Data are also presented on the performance of IRAC beamsplitters at room temperature at both 0 and 45 deg angle of incidence and on the performance of the all-reflecting optical system baselined for the camera.

Mechanical Designs and Developement of Advanced ACT: A Transfomative Upgrade to the ACTPol Receiver on the Atacama Cosmology Telescope.

NASA Astrophysics Data System (ADS)

Ward, Jonathan; Advanced ACT Collaboration, NASA Space Technology Research Fellowship

2017-06-01

The Atacama Cosmology Telescope is a six-meter diameter telescope located at 17,000 feet (5,200 meters) on Cerro Toco in the Andes Mountains of northern Chile. The next generation Advanced ACT (AdvACT) experiment is currently underway and will consist of three multichroic TES bolometer arrays operating together, totaling 5800 detectors on the sky. Each array will be sensitive to two frequency bands: a high frequency (HF) array at 150 and 230 GHz, two middle frequency (MF) arrays at 90 and 150 GHz, and a low frequency (LF) array at 28 and 41 GHz. The AdACT detector arrays will feature a revamped design when compared to ACTPol, including a transition to 150mm wafers equipped with multichroic pixels, allowing for a more densely packed focal plane. Each set of detectors consists of a feedhorn array of stacked silicon wafers which form a corrugated profile leading to each pixel. This is then followed by a four-piece detector stack assembly of silicon wafers which includes a waveguide interface plate, detector wafer, backshort cavity plate, and backshort cap. Each array is housed in a custom designed structure manufactured out of gold-plated, high purity copper. In addition to the detector array assembly, the array package also encloses the majority of our readout electronics. We present the full mechanical design of the AdvACT HF and MF detector array packages along with a detailed look at the detector array assemblies. We also highlight the use of continuously rotating warm half-wave plates (HWPs) at the front of the AdvACT receiver. We review the design of the rotation system and also early pipeline data analysis results. This experiment will also make use of extensive hardware and software previously developed for ACT, which will be modified to incorporate the new AdvACT instruments. Therefore, we discuss the integration of all AdvACT instruments with pre-existing ACTPol infrastructure.

Antarctic observations at long wavelengths with the IRAIT-ITM Telescope at Dome C

NASA Astrophysics Data System (ADS)

Durand, Gilles A.; Tremblin, Pascal; Minier, Vincent; Reinert, Yann; Leroy dos Santos, Christophe; Rodriguez, Louis; Joffrin, Xavier; Busso, Maurizio; Tosti, Gino; Nucciarelli, Giuliano; Dolci, Mauro; Straniero, Oscar; Valentini, Angelo; Abia, Carlos; Christille, Jean Marc; Doumayrou, Eric; Lortholary, Michel; Charron, Patrice; Lotrus, Paul; Walter, Christian; Ronayette, Samuel; Challita, Zalpha; Fromont, Laurent; Condamin, Mathieu; Kwon, Min Kyong; Tavagnacco, Daniele

2014-07-01

We illustrate the status of the international infra-red telescope IRAIT-ITM, a project developed thanks to an Italian- Spanish-French collaboration and now sited at the Dome C Antarctic base. The telescope and its subsystems were installed at DomeC by a team of Italian and French scientists. The 80 cm telescope is placed on a small snow hill next to a laboratory of astronomy. The operations started in January 2013, with the Nasmyth focal planes equipped with the midinfrared camera AMICA for 1.25 to 25 μm and the sub-millimetre camera CAMISTIC for observation of the sky noise at 200 and 350 μm using a bolometer camera. During 2013 the two winter-overs worked mainly on technological duties, learning how to operate the telescope, while temperatures decreased down to -80°C. The cryogenic systems could be operated respectively at 0.25K and 4K at all times, with satisfactory use of the heat from the compressors of the cryocoolers to the warm-up the laboratory through a closed loop glycol system. The lack of tests and reliability in extreme conditions of some components and difficult access to maintenance hampered regular observations below -50°C. Using the lessons of this first winter, the summer team improves the robustness of the failing systems and ease the access to maintenance. The winter 2014 is the first one with programmed observations. Because of power restrictions, the two instruments are used each one at a time by periods of 2 weeks. The Camistic camera continues to observe the stability of the sky at a fixed altitude in chopping mode and performs skydips. The TCS is being upgraded in order to prepare the next summer season with extensive observations of the sun with Camistic.

A time-resolved image sensor for tubeless streak cameras

NASA Astrophysics Data System (ADS)

Yasutomi, Keita; Han, SangMan; Seo, Min-Woong; Takasawa, Taishi; Kagawa, Keiichiro; Kawahito, Shoji

2014-03-01

This paper presents a time-resolved CMOS image sensor with draining-only modulation (DOM) pixels for tube-less streak cameras. Although the conventional streak camera has high time resolution, the device requires high voltage and bulky system due to the structure with a vacuum tube. The proposed time-resolved imager with a simple optics realize a streak camera without any vacuum tubes. The proposed image sensor has DOM pixels, a delay-based pulse generator, and a readout circuitry. The delay-based pulse generator in combination with an in-pixel logic allows us to create and to provide a short gating clock to the pixel array. A prototype time-resolved CMOS image sensor with the proposed pixel is designed and implemented using 0.11um CMOS image sensor technology. The image array has 30(Vertical) x 128(Memory length) pixels with the pixel pitch of 22.4um. .

KSC-01pp1760

NASA Image and Video Library

2001-11-29

KENNEDY SPACE CENTER, Fla. -- Fully unwrapped, the Advanced Camera for Surveys, which is suspended by an overhead crane, is checked over by workers. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

Lens and Camera Arrays for Sky Surveys and Space Surveillance

NASA Astrophysics Data System (ADS)

Ackermann, M.; Cox, D.; McGraw, J.; Zimmer, P.

2016-09-01

In recent years, a number of sky survey projects have chosen to use arrays of commercial cameras coupled with commercial photographic lenses to enable low-cost, wide-area observation. Projects such as SuperWASP, FAVOR, RAPTOR, Lotis, PANOPTES, and DragonFly rely on multiple cameras with commercial lenses to image wide areas of the sky each night. The sensors are usually commercial astronomical charge coupled devices (CCDs) or digital single reflex (DSLR) cameras, while the lenses are large-aperture, highend consumer items intended for general photography. While much of this equipment is very capable and relatively inexpensive, this approach comes with a number of significant limitations that reduce sensitivity and overall utility of the image data. The most frequently encountered limitations include lens vignetting, narrow spectral bandpass, and a relatively large point spread function. Understanding these limits helps to assess the utility of the data, and identify areas where advanced optical designs could significantly improve survey performance.

Thermal Infrared Imaging Experiments of C-Type Asteroid 162173 Ryugu on Hayabusa2

NASA Astrophysics Data System (ADS)

Okada, Tatsuaki; Fukuhara, Tetsuya; Tanaka, Satoshi; Taguchi, Makoto; Imamura, Takeshi; Arai, Takehiko; Senshu, Hiroki; Ogawa, Yoshiko; Demura, Hirohide; Kitazato, Kohei; Nakamura, Ryosuke; Kouyama, Toru; Sekiguchi, Tomohiko; Hasegawa, Sunao; Matsunaga, Tsuneo; Wada, Takehiko; Takita, Jun; Sakatani, Naoya; Horikawa, Yamato; Endo, Ken; Helbert, Jörn; Müller, Thomas G.; Hagermann, Axel

2017-07-01

The thermal infrared imager TIR onboard Hayabusa2 has been developed to investigate thermo-physical properties of C-type, near-Earth asteroid 162173 Ryugu. TIR is one of the remote science instruments on Hayabusa2 designed to understand the nature of a volatile-rich solar system small body, but it also has significant mission objectives to provide information on surface physical properties and conditions for sampling site selection as well as the assessment of safe landing operations. TIR is based on a two-dimensional uncooled micro-bolometer array inherited from the Longwave Infrared Camera LIR on Akatsuki (Fukuhara et al., 2011). TIR takes images of thermal infrared emission in 8 to 12 μm with a field of view of 16 × 12° and a spatial resolution of 0.05° per pixel. TIR covers the temperature range from 150 to 460 K, including the well calibrated range from 230 to 420 K. Temperature accuracy is within 2 K or better for summed images, and the relative accuracy or noise equivalent temperature difference (NETD) at each of pixels is 0.4 K or lower for the well-calibrated temperature range. TIR takes a couple of images with shutter open and closed, the corresponding dark frame, and provides a true thermal image by dark frame subtraction. Data processing involves summation of multiple images, image processing including the StarPixel compression (Hihara et al., 2014), and transfer to the data recorder in the spacecraft digital electronics (DE). We report the scientific and mission objectives of TIR, the requirements and constraints for the instrument specifications, the designed instrumentation and the pre-flight and in-flight performances of TIR, as well as its observation plan during the Hayabusa2 mission.

Adaptive Wiener filter super-resolution of color filter array images.

PubMed

Karch, Barry K; Hardie, Russell C

2013-08-12

Digital color cameras using a single detector array with a Bayer color filter array (CFA) require interpolation or demosaicing to estimate missing color information and provide full-color images. However, demosaicing does not specifically address fundamental undersampling and aliasing inherent in typical camera designs. Fast non-uniform interpolation based super-resolution (SR) is an attractive approach to reduce or eliminate aliasing and its relatively low computational load is amenable to real-time applications. The adaptive Wiener filter (AWF) SR algorithm was initially developed for grayscale imaging and has not previously been applied to color SR demosaicing. Here, we develop a novel fast SR method for CFA cameras that is based on the AWF SR algorithm and uses global channel-to-channel statistical models. We apply this new method as a stand-alone algorithm and also as an initialization image for a variational SR algorithm. This paper presents the theoretical development of the color AWF SR approach and applies it in performance comparisons to other SR techniques for both simulated and real data.

High energy X-ray pinhole imaging at the Z facility

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

McPherson, L. Armon; Ampleford, David J., E-mail: damplef@sandia.gov; Coverdale, Christine A.

A new high photon energy (hν > 15 keV) time-integrated pinhole camera (TIPC) has been developed as a diagnostic instrument at the Z facility. This camera employs five pinholes in a linear array for recording five images at once onto an image plate detector. Each pinhole may be independently filtered to yield five different spectral responses. The pinhole array is fabricated from a 1-cm thick tungsten block and is available with either straight pinholes or conical pinholes. Each pinhole within the array block is 250 μm in diameter. The five pinholes are splayed with respect to each other such thatmore » they point to the same location in space, and hence present the same view of the radiation source at the Z facility. The fielding distance from the radiation source is 66 cm and the nominal image magnification is 0.374. Initial experimental results from TIPC are shown to illustrate the performance of the camera.« less

Camera array based light field microscopy

PubMed Central

Lin, Xing; Wu, Jiamin; Zheng, Guoan; Dai, Qionghai

2015-01-01

This paper proposes a novel approach for high-resolution light field microscopy imaging by using a camera array. In this approach, we apply a two-stage relay system for expanding the aperture plane of the microscope into the size of an imaging lens array, and utilize a sensor array for acquiring different sub-apertures images formed by corresponding imaging lenses. By combining the rectified and synchronized images from 5 × 5 viewpoints with our prototype system, we successfully recovered color light field videos for various fast-moving microscopic specimens with a spatial resolution of 0.79 megapixels at 30 frames per second, corresponding to an unprecedented data throughput of 562.5 MB/s for light field microscopy. We also demonstrated the use of the reported platform for different applications, including post-capture refocusing, phase reconstruction, 3D imaging, and optical metrology. PMID:26417490

Simulation Study of the Localization of a Near-Surface Crack Using an Air-Coupled Ultrasonic Sensor Array

PubMed Central

Delrue, Steven; Aleshin, Vladislav; Sørensen, Mikael; De Lathauwer, Lieven

2017-01-01

The importance of Non-Destructive Testing (NDT) to check the integrity of materials in different fields of industry has increased significantly in recent years. Actually, industry demands NDT methods that allow fast (preferably non-contact) detection and localization of early-stage defects with easy-to-interpret results, so that even a non-expert field worker can carry out the testing. The main challenge is to combine as many of these requirements into one single technique. The concept of acoustic cameras, developed for low frequency NDT, meets most of the above-mentioned requirements. These cameras make use of an array of microphones to visualize noise sources by estimating the Direction Of Arrival (DOA) of the impinging sound waves. Until now, however, because of limitations in the frequency range and the lack of integrated nonlinear post-processing, acoustic camera systems have never been used for the localization of incipient damage. The goal of the current paper is to numerically investigate the capabilities of locating incipient damage by measuring the nonlinear airborne emission of the defect using a non-contact ultrasonic sensor array. We will consider a simple case of a sample with a single near-surface crack and prove that after efficient excitation of the defect sample, the nonlinear defect responses can be detected by a uniform linear sensor array. These responses are then used to determine the location of the defect by means of three different DOA algorithms. The results obtained in this study can be considered as a first step towards the development of a nonlinear ultrasonic camera system, comprising the ultrasonic sensor array as the hardware and nonlinear post-processing and source localization software. PMID:28441738

15 CFR 742.4 - National security.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Requirements” section except those cameras in ECCN 6A003.b.4.b that have a focal plane array with 111,000 or..., South Korea, Spain, Sweden, Switzerland, Turkey, and the United Kingdom for those cameras in ECCN 6A003...

15 CFR 742.4 - National security.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Requirements” section except those cameras in ECCN 6A003.b.4.b that have a focal plane array with 111,000 or..., South Korea, Spain, Sweden, Switzerland, Turkey, and the United Kingdom for those cameras in ECCN 6A003...

15 CFR 742.4 - National security.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Requirements” section except those cameras in ECCN 6A003.b.4.b that have a focal plane array with 111,000 or..., South Korea, Spain, Sweden, Switzerland, Turkey, and the United Kingdom for those cameras in ECCN 6A003...

15 CFR 742.4 - National security.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Requirements” section except those cameras in ECCN 6A003.b.4.b that have a focal plane array with 111,000 or..., South Korea, Spain, Sweden, Switzerland, Turkey, and the United Kingdom for those cameras in ECCN 6A003...

Lytro camera technology: theory, algorithms, performance analysis

NASA Astrophysics Data System (ADS)

Georgiev, Todor; Yu, Zhan; Lumsdaine, Andrew; Goma, Sergio

2013-03-01

The Lytro camera is the first implementation of a plenoptic camera for the consumer market. We consider it a successful example of the miniaturization aided by the increase in computational power characterizing mobile computational photography. The plenoptic camera approach to radiance capture uses a microlens array as an imaging system focused on the focal plane of the main camera lens. This paper analyzes the performance of Lytro camera from a system level perspective, considering the Lytro camera as a black box, and uses our interpretation of Lytro image data saved by the camera. We present our findings based on our interpretation of Lytro camera file structure, image calibration and image rendering; in this context, artifacts and final image resolution are discussed.

The software architecture of the camera for the ASTRI SST-2M prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Sangiorgi, Pierluca; Capalbi, Milvia; Gimenes, Renato; La Rosa, Giovanni; Russo, Francesco; Segreto, Alberto; Sottile, Giuseppe; Catalano, Osvaldo

2016-07-01

The purpose of this contribution is to present the current status of the software architecture of the ASTRI SST-2M Cherenkov Camera. The ASTRI SST-2M telescope is an end-to-end prototype for the Small Size Telescope of the Cherenkov Telescope Array. The ASTRI camera is an innovative instrument based on SiPM detectors and has several internal hardware components. In this contribution we will give a brief description of the hardware components of the camera of the ASTRI SST-2M prototype and of their interconnections. Then we will present the outcome of the software architectural design process that we carried out in order to identify the main structural components of the camera software system and the relationships among them. We will analyze the architectural model that describes how the camera software is organized as a set of communicating blocks. Finally, we will show where these blocks are deployed in the hardware components and how they interact. We will describe in some detail, the physical communication ports and external ancillary devices management, the high precision time-tag management, the fast data collection and the fast data exchange between different camera subsystems, and the interfacing with the external systems.

Nanostructure based EO/IR sensor development for homeland security applications

NASA Astrophysics Data System (ADS)

Sood, Ashok K.; Welser, Roger E.; Sood, Adam W.; Puri, Yash R.; Manzur, Tariq; Dhar, Nibir K.; Polla, Dennis L.; Wang, Zhong L.; Wijewarnasuriya, Priyalal S.; Anwar, A. F. M.

2011-06-01

Next Generation EO/IR focal plane arrays using nanostructure materials are being developed for a variety of Defense and Homeland Security Sensor Applications. Several different nanomaterials are being evaluated for these applications. These include ZnO nanowires, GaN Nanowires and II-VI nanowires, which have demonstrated large signal to noise ratio as a wide band gap nanostructure material in the UV band. Similarly, the work is under way using Carbon Nanotubes (CNT) for a high speed detector and focal plane array as two-dimensional array as bolometer for IR bands of interest, which can be implemented for the sensors for homeland security applications. In this paper, we will discuss the sensor design and model predicting performance of an EO/IR focal plane array and Sensor that can cover the UV to IR bands of interest. The model can provide a robust means for comparing performance of the EO/IR FPA's and Sensors that can operate in the UV, Visible-NIR (0.4- 1.8μ), SWIR (2.0-2.5μ), MWIR (3-5μ), and LWIR bands (8-14μ). This model can be used as a tool for predicting performance of nanostructure arrays under development. We will also discuss our results on growth and characterization of ZnO nanowires and CNT's for the next generation sensor applications. We also present several approaches for integrated energy harvesting using nanostructure based solar cells and Nanogenerators that can be used to supplement the energy required for nanostructure based sensors.

Instrument development of the CMB polarization POLARBEAR-2 experiment

NASA Astrophysics Data System (ADS)

Siritanasak, Praween; POLARBEAR Collaboration

2017-06-01

We present the status of the development of the Polarbear-2 (PB-2) and Simons Array experiments. PB-2 is a ground-based Cosmic Microwave Back- ground (CMB) polarization experiment located at the James Ax observatory in the Atacama desert of Northern Chile. The Simons Array will consist of three PB-2 receivers on three Huan Tran-style telescopes, each containing a multi-chroic detector array. The first new Simons Array receiver, Polarbear- 2A(PB-2A), will be deployed in 2017. The PB-2A focal plane consists of 1,897 lenslet-coupled, dual-polarization, sinuous-antenna-coupled pixels operating at 95 and 150 GHz, making a total of 7,588 polarization-sensitive transition edge sensor (TES) bolometers. In the order to cover both frequencies, we developed broadband two layer anti-reflection (AR) coating for 5.345 mm diameter lenslets using two types of epoxy: Stycast2850FT and Stycast1090. We developed a mass production AR coating methodology that can control the uniformity and shape to within 25 μm error from the designed value. The second (PB-2B) and third (PB-2C) receivers will employ similar technologies and will cover 95, 150, 220 and 280 GHz. The Simons Array will survey 80% of the sky with broad frequency coverage and high resolution, making it a powerful tool to constrain the tensor-to-scalar ratio through measurements of primordial B-modes and the sum of the neutrino masses through measurements of B-modes produced by gravitational lensing.

The Polarbear-2 and the Simons Array experiments

DOE PAGES

Suzuki, A.; Ade, P.; Akiba, Y.; ...

2016-01-06

Here, we present an overview of the design and status of the POLARBEAR-2 and the Simons Array experiments. POLARBEAR- 2 is a Cosmic Microwave Background polarimetry experiment which aims to characterize the arc-minute angular scale B-mode signal from weak gravitational lensing and search for the degree angular scale B-mode signal from inflationary gravitational waves. The receiver has a 365 mm diameter focal plane cooled to 270 milli-Kelvin. The focal plane is filled with 7,588 dichroic lenslet-antenna coupled polarization sensitive Transition Edge Sensor (TES) bolometric pixels that are sensitive to 95 GHz and 150 GHz bands simultaneously. The TES bolometers aremore » read-out by SQUIDs with 40 channel frequency domain multiplexing. Refractive optical elements are made with high purity alumina to achieve high optical throughput. The receiver is designed to achieve noise equivalent temperature of 5.8 µK CMB√s in each frequency band. POLARBEAR-2 will deploy in 2016 in the Atacama desert in Chile. The Simons Array is a project to further increase sensitivity by deploying three POLARBEAR-2 type receivers. The Simons Array will cover 95 GHz, 150 GHz and 220 GHz frequency bands for foreground control. The Simons Array will be able to constrain tensor-to-scalar ratio and sum of neutrino masses to σ(r) = 6×10 $-$3 at r = 0.1 and Σm ν(σ = 1) to 40 meV.« less

An ultrahigh-speed color video camera operating at 1,000,000 fps with 288 frame memories

NASA Astrophysics Data System (ADS)

Kitamura, K.; Arai, T.; Yonai, J.; Hayashida, T.; Kurita, T.; Maruyama, H.; Namiki, J.; Yanagi, T.; Yoshida, T.; van Kuijk, H.; Bosiers, Jan T.; Saita, A.; Kanayama, S.; Hatade, K.; Kitagawa, S.; Etoh, T. Goji

2008-11-01

We developed an ultrahigh-speed color video camera that operates at 1,000,000 fps (frames per second) and had capacity to store 288 frame memories. In 2005, we developed an ultrahigh-speed, high-sensitivity portable color camera with a 300,000-pixel single CCD (ISIS-V4: In-situ Storage Image Sensor, Version 4). Its ultrahigh-speed shooting capability of 1,000,000 fps was made possible by directly connecting CCD storages, which record video images, to the photodiodes of individual pixels. The number of consecutive frames was 144. However, longer capture times were demanded when the camera was used during imaging experiments and for some television programs. To increase ultrahigh-speed capture times, we used a beam splitter and two ultrahigh-speed 300,000-pixel CCDs. The beam splitter was placed behind the pick up lens. One CCD was located at each of the two outputs of the beam splitter. The CCD driving unit was developed to separately drive two CCDs, and the recording period of the two CCDs was sequentially switched. This increased the recording capacity to 288 images, an increase of a factor of two over that of conventional ultrahigh-speed camera. A problem with the camera was that the incident light on each CCD was reduced by a factor of two by using the beam splitter. To improve the light sensitivity, we developed a microlens array for use with the ultrahigh-speed CCDs. We simulated the operation of the microlens array in order to optimize its shape and then fabricated it using stamping technology. Using this microlens increased the light sensitivity of the CCDs by an approximate factor of two. By using a beam splitter in conjunction with the microlens array, it was possible to make an ultrahigh-speed color video camera that has 288 frame memories but without decreasing the camera's light sensitivity.

ATTICA family of thermal cameras in submarine applications

NASA Astrophysics Data System (ADS)

Kuerbitz, Gunther; Fritze, Joerg; Hoefft, Jens-Rainer; Ruf, Berthold

2001-10-01

Optronics Mast Systems (US: Photonics Mast Systems) are electro-optical devices which enable a submarine crew to observe the scenery above water during dive. Unlike classical submarine periscopes they are non-hull-penetrating and therefore have no direct viewing capability. Typically they have electro-optical cameras both for the visual and for an IR spectral band with panoramic view and a stabilized line of sight. They can optionally be equipped with laser range- finders, antennas, etc. The brand name ATTICA (Advanced Two- dimensional Thermal Imager with CMOS-Array) characterizes a family of thermal cameras using focal-plane-array (FPA) detectors which can be tailored to a variety of requirements. The modular design of the ATTICA components allows the use of various detectors (InSb, CMT 3...5 μm , CMT 7...11 μm ) for specific applications. By means of a microscanner ATTICA cameras achieve full standard TV resolution using detectors with only 288 X 384 (US:240 X 320) detector elements. A typical requirement for Optronics-Mast Systems is a Quick- Look-Around capability. For FPA cameras this implies the need for a 'descan' module which can be incorporated in the ATTICA cameras without complications.

Development of an all-in-one gamma camera/CCD system for safeguard verification

NASA Astrophysics Data System (ADS)

Kim, Hyun-Il; An, Su Jung; Chung, Yong Hyun; Kwak, Sung-Woo

2014-12-01

For the purpose of monitoring and verifying efforts at safeguarding radioactive materials in various fields, a new all-in-one gamma camera/charged coupled device (CCD) system was developed. This combined system consists of a gamma camera, which gathers energy and position information on gamma-ray sources, and a CCD camera, which identifies the specific location in a monitored area. Therefore, 2-D image information and quantitative information regarding gamma-ray sources can be obtained using fused images. A gamma camera consists of a diverging collimator, a 22 × 22 array CsI(Na) pixelated scintillation crystal with a pixel size of 2 × 2 × 6 mm3 and Hamamatsu H8500 position-sensitive photomultiplier tube (PSPMT). The Basler scA640-70gc CCD camera, which delivers 70 frames per second at video graphics array (VGA) resolution, was employed. Performance testing was performed using a Co-57 point source 30 cm from the detector. The measured spatial resolution and sensitivity were 4.77 mm full width at half maximum (FWHM) and 7.78 cps/MBq, respectively. The energy resolution was 18% at 122 keV. These results demonstrate that the combined system has considerable potential for radiation monitoring.

TES arrays for the short wavelength band of the SAFARI instrument on SPICA

NASA Astrophysics Data System (ADS)

Khosropanah, P.; Hijmering, R.; Ridder, M.; Gao, J. R.; Morozov, D.; Mauskopf, P. D.; Trappe, N.; O'Sullivan, C.; Murphy, A.; Griffin, D.; Goldie, D.; Glowacka, D.; Withington, S.; Jackson, B. D.; Audley, M. D.; de Lange, G.

2012-09-01

SPICA is an infra-red (IR) telescope with a cryogenically cooled mirror (~5K) with three instruments on board, one of which is SAFARI that is an imaging Fourier Transform Spectrometer (FTS) with three bands covering the wavelength of 34-210 μm. We develop transition edge sensors (TES) array for short wavelength band (34-60 μm) of SAFARI. These are based on superconducting Ti/Au bilayer as TES bolometers with a Tc of about 105 mK and thin Ta film as IR absorbers on suspended silicon nitride (SiN) membranes. These membranes are supported by long and narrow SiN legs that act as weak thermal links between the TES and the bath. Previously an electrical noise equivalent power (NEP) of 4×10-19 W/√Hz was achieved for a single pixel of such detectors. As an intermediate step toward a full-size SAFARI array (43×43), we fabricated several 8×9 detector arrays. Here we describe the design and the outcome of the dark and optical tests of several of these devices. We achieved high yield (<93%) and high uniformity in terms of critical temperature (<5%) and normal resistance (7%) across the arrays. The measured dark NEPs are as low as 5×10-19 W/√Hz with a response time of about 1.4 ms at preferred operating bias point. The optical coupling is implemented using pyramidal horns array on the top and hemispherical cavity behind the chip that gives a measured total optical coupling efficiency of 30±7%.

The ITER bolometer diagnostic: Status and plansa)

NASA Astrophysics Data System (ADS)

Meister, H.; Giannone, L.; Horton, L. D.; Raupp, G.; Zeidner, W.; Grunda, G.; Kalvin, S.; Fischer, U.; Serikov, A.; Stickel, S.; Reichle, R.

2008-10-01

A consortium consisting of four EURATOM Associations has been set up to develop the project plan for the full development of the ITER bolometer diagnostic and to continue urgent R&D activities. An overview of the current status is given, including detector development, line-of-sight optimization, performance analysis as well as the design of the diagnostic components and their integration in ITER. This is complemented by the presentation of plans for future activities required to successfully implement the bolometer diagnostic, ranging from the detector development over diagnostic design and prototype testing to RH tools for calibration.

SINIS bolometer with a suspended absorber

NASA Astrophysics Data System (ADS)

Tarasov, M.; Edelman, V.; Mahashabde, S.; Fominsky, M.; Lemzyakov, S.; Chekushkin, A.; Yusupov, R.; Winkler, D.; Yurgens, A.

2018-03-01

We have developed a Superconductor-Insulator-Normal Metal-Insulator-Superconductor (SINIS) bolometer with a suspended normal metal bridge. The suspended bridge acts as a bolometric absorber with reduced heat losses to the substrate. Such bolometers were characterized at 100-350 mK bath temperatures and electrical responsivity of over 109 V/W was measured by dc heating the absorber through additional contacts. Suspended bolometers were also integrated in planar twin-slot and log-periodic antennas for operation in the submillimetre-band of radiation. The measured voltage response to radiation at 300 GHz and at 100 mK bath temperature is 3*108 V/W and a current response is 1.1*104 A/W which corresponds to a quantum efficiency of ~15 electrons per photon. An important feature of such suspended bolometers is the thermalization of electrons in the absorber heated by optical radiation, which in turn provides better quantum efficiency. This has been confirmed by comparison of bolometric response to dc and rf heating. We investigate the performance of direct SN traps and NIS traps with a tunnel barrier between the superconductor and normal metal trap. Increasing the volume of superconducting electrode helps to reduce overheating of superconductor. Influence of Andreev reflection and Kapitza resistance, as well as electron-phonon heat conductivity and thermal conductivity of N-wiring are estimated for such SINIS devices.

Technological development of multispectral filter assemblies for micro bolometer

NASA Astrophysics Data System (ADS)

Le Goff, Roland; Tanguy, François; Fuss, Philippe; Etcheto, Pierre

2017-11-01

Since 2007 Sodern has successfully developed visible and near infrared multispectral filter assemblies for Earth remote sensing imagers. Filter assembly is manufactured by assembling several sliced filter elements (so-called strips), each corresponding to one spectral band. These strips are cut from wafers using a two dimensional accuracy precision process. In the frame of a 2011 R&T preparatory initiative undertaken by the French agency CNES, the filter assembly concept was adapted by Sodern to the long wave infrared spectral band taken into account the germanium substrate, the multilayer bandpass filters and the F-number of the optics. Indeed the current trend in space instrumentation toward more compact uncooled infrared radiometer leads to replace the filter wheel with a multispectral filter assembly mounted directly above the micro bolometer window. The filter assembly was customized to fit the bolometer size. For this development activity we consider a ULIS VGA LWIR micro bolometer with 640 by 480 pixels and 25 microns pixel pitch. The feasibility of the concept and the ability to withstand space environment were investigated and demonstrated by bread boarding activities. The presentation will contain a detailed description of the bolometer and filter assembly design, the stray light modeling analysis assessing the crosstalk between adjacent spectral bands and the results of the manufacturing and environmental tests (damp heat and thermal vacuum cycling).

Heat trap - An optimized far infrared field optics system. [for astronomical sources

NASA Technical Reports Server (NTRS)

Harper, D. A.; Hildebrand, R. H.; Winston, R.; Stiening, R.

1976-01-01

The article deals with the design and performance of a heat trap IR system designed to maximize the concentration and efficient reception of far IR and submillimeter wavelength radiation. The test object is assumed to be extended and/or viewed at wavelengths much longer than the detector, and the entrance aperture is limited to the size of the telescope Airy diffraction disk. The design of lenses, cavity, bolometers, light collectors, and mirrors for the system is discussed. Advantages and feasibility of arrays of heat traps are considered. Beam patterns, flux concentration, and performance variation with wavelength are dealt with. The heat trap is recommended for sensing all types of far IR sources and particularly for extended far IR sources.-

Fabrication of Monolithic Sapphire Membranes for High T(sub c) Bolometer Array Development

NASA Technical Reports Server (NTRS)

Pugel, D. E.; Lakew, B.; Aslam, S.; Wang, L.

2004-01-01

This paper examines the effectiveness of Pt/Cr thin film masks for the architecture of monolithic membrane structures in r-plane single crystal sapphire. The development of a pinhole-free Pt/Cr composite mask that is resistant to boiling H2SO4:H3PO4 etchant will lead to the fabrication of smooth sapphire membranes whose surfaces are well-suited for the growth of low-noise high Tc films. In particular, the relationship of thermal annealing conditions on the Pt/Cr composite mask system to: (1) changes in the surface morphology (2) elemental concentration of the Pt/Cr thin film layers and (3) etch pit formation on the sapphire surface will be presented.

Waveguide modes in sparse III-V nanowire arrays for ultra-broadband tunable perfect absorbers (Conference Presentation)

NASA Astrophysics Data System (ADS)

Fountaine, Katherine T.; Cheng, Wen-Hui; Bukowsky, Colton R.; Atwater, Harry A.

2016-09-01

Design of perfect absorbers and emitters has been a primary focus of the metamaterials community owing to their potential to enhance device efficiency and sensitivity in energy harvesting and sensing applications, specifically photovoltaics, thermal emission control, bolometers and photodetectors, to name a few. While reports of perfect absorbers/emitters for a specific frequency, wavevector, and polarization are ubiquitous, a broadband and polarization- and angle-insensitive perfect absorber remains a particular challenge. In this work, we report on directed optical design and fabrication of sparse III-V nanowire arrays as broadband, polarization- and angle-insensitive perfect absorbers and emitters. Specifically, we target response in the UV-Vis-NIR and NIR-SWIR-MWIR via two material systems, InP (Eg=1.34 eV) and InSb (Eg=0.17 eV), respectively. Herein, we present results on InP and InSb nanowire array broadband absorbers, supported by experiment, simulation and analytic theory. Electromagnetic simulations indicate that, with directed optical design, tapered nanowire arrays and multi-radii nanowire arrays with 5% fill fraction can achieve greater than 95% broadband absorption (λInP=400-900nm, λInSb=1.5-5.5µm), due to efficient excitation and interband transition-mediated attenuation of the HE11 waveguide mode. Experimentally-fabricated InP nanowire arrays embedded in PDMS achieved broadband, polarization- and angle-insensitive 90-95% absorption, limited primarily by reflection off the PDMS interface. Addition of a thin, planar VO2 layer above a sparse InSb nanowire array enables active thermal tunability in the infrared, effecting a 50% modulation, from 87% (insulating VO2) to 43% (metallic VO2) average absorption. These concepts and results along with photovoltaic and other optical and optoelectronic device applications will be discussed.

Proportional counter radiation camera

DOEpatents

Borkowski, C.J.; Kopp, M.K.

1974-01-15

A gas-filled proportional counter camera that images photon emitting sources is described. A two-dimensional, positionsensitive proportional multiwire counter is provided as the detector. The counter consists of a high- voltage anode screen sandwiched between orthogonally disposed planar arrays of multiple parallel strung, resistively coupled cathode wires. Two terminals from each of the cathode arrays are connected to separate timing circuitry to obtain separate X and Y coordinate signal values from pulse shape measurements to define the position of an event within the counter arrays which may be recorded by various means for data display. The counter is further provided with a linear drift field which effectively enlarges the active gas volume of the counter and constrains the recoil electrons produced from ionizing radiation entering the counter to drift perpendicularly toward the planar detection arrays. A collimator is interposed between a subject to be imaged and the counter to transmit only the radiation from the subject which has a perpendicular trajectory with respect to the planar cathode arrays of the detector. (Official Gazette)

15-micro-m 128 x 128 GaAs/Al(x)Ga(1-x) As Quantum Well Infrared Photodetector Focal Plane Array Camera

NASA Technical Reports Server (NTRS)

Gunapala, Sarath D.; Park, Jin S.; Sarusi, Gabby; Lin, True-Lon; Liu, John K.; Maker, Paul D.; Muller, Richard E.; Shott, Craig A.; Hoelter, Ted

1997-01-01

In this paper, we discuss the development of very sensitive, very long wavelength infrared GaAs/Al(x)Ga(1-x)As quantum well infrared photodetectors (QWIP's) based on bound-to-quasi-bound intersubband transition, fabrication of random reflectors for efficient light coupling, and the demonstration of a 15 micro-m cutoff 128 x 128 focal plane array imaging camera. Excellent imagery, with a noise equivalent differential temperature (N E(delta T)) of 30 mK has been achieved.

Calibrating Images from the MINERVA Cameras

NASA Astrophysics Data System (ADS)

Mercedes Colón, Ana

2016-01-01

The MINiature Exoplanet Radial Velocity Array (MINERVA) consists of an array of robotic telescopes located on Mount Hopkins, Arizona with the purpose of performing transit photometry and spectroscopy to find Earth-like planets around Sun-like stars. In order to make photometric observations, it is necessary to perform calibrations on the CCD cameras of the telescopes to take into account possible instrument error on the data. In this project, we developed a pipeline that takes optical images, calibrates them using sky flats, darks, and biases to generate a transit light curve.

Spectral Characterizations of the Clouds and the Earth's Radiant Energy System (CERES) Thermistor Bolometers using Fourier Transform Spectrometer (FTS) Techniques

NASA Technical Reports Server (NTRS)

Thornhill, K. Lee; Bitting, Herbert; Lee, Robert B., III; Paden, Jack; Pandey, Dhirendra K.; Priestley, Kory J.; Thomas, Susan; Wilson, Robert S.

1998-01-01

Fourier Transform Spectrometer (FTS) techniques are being used to characterize the relative spectral response, or sensitivity, of scanning thermistor bolometers in the infrared (IR) region (2 - >= 100-micrometers). The bolometers are being used in the Clouds and the Earth's Radiant Energy System (CERES) program. The CERES measurements are designed to provide precise, long term monitoring of the Earth's atmospheric radiation energy budget. The CERES instrument houses three bolometric radiometers, a total wavelength (0.3- >= 150-micrometers) sensor, a shortwave (0.3-5-micrometers) sensor, and an atmospheric window (8-12-micrometers) sensor. Accurate spectral characterization is necessary for determining filtered radiances for longwave radiometric calibrations. The CERES bolometers spectral response's are measured in the TRW FTS Vacuum Chamber Facility (FTS - VCF), which uses a FTS as the source and a cavity pyroelectric trap detector as the reference. The CERES bolometers and the cavity detector are contained in a vacuum chamber, while the FTS source is housed in a GN2 purged chamber. Due to the thermal time constant of the CERES bolometers, the FTS must be operated in a step mode. Data are acquired in 6 IR spectral bands covering the entire longwave IR region. In this paper, the TRW spectral calibration facility design and data measurement techniques are described. Two approaches are presented which convert the total channel FTS data into the final CERES spectral characterizations, producing the same calibration coefficients (within 0.1 percent). The resulting spectral response curves are shown, along with error sources in the two procedures. Finally, the impact of each spectral response curve on CERES data validation will be examined through analysis of filtered radiance values from various typical scene types.

Retinal fundus imaging with a plenoptic sensor

NASA Astrophysics Data System (ADS)

Thurin, Brice; Bloch, Edward; Nousias, Sotiris; Ourselin, Sebastien; Keane, Pearse; Bergeles, Christos

2018-02-01

Vitreoretinal surgery is moving towards 3D visualization of the surgical field. This require acquisition system capable of recording such 3D information. We propose a proof of concept imaging system based on a light-field camera where an array of micro-lenses is placed in front of a conventional sensor. With a single snapshot, a stack of images focused at different depth are produced on the fly, which provides enhanced depth perception for the surgeon. Difficulty in depth localization of features and frequent focus-change during surgery are making current vitreoretinal heads-up surgical imaging systems cumbersome to use. To improve the depth perception and eliminate the need to manually refocus on the instruments during the surgery, we designed and implemented a proof-of-concept ophthalmoscope equipped with a commercial light-field camera. The sensor of our camera is composed of an array of micro-lenses which are projecting an array of overlapped micro-images. We show that with a single light-field snapshot we can digitally refocus between the retina and a tool located in front of the retina or display an extended depth-of-field image where everything is in focus. The design and system performances of the plenoptic fundus camera are detailed. We will conclude by showing in vivo data recorded with our device.

Imaging spectrometer/camera having convex grating

NASA Technical Reports Server (NTRS)

Reininger, Francis M. (Inventor)

2000-01-01

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.

In-Space Structural Validation Plan for a Stretched-Lens Solar Array Flight Experiment

NASA Technical Reports Server (NTRS)

Pappa, Richard S.; Woods-Vedeler, Jessica A.; Jones, Thomas W.

2001-01-01

This paper summarizes in-space structural validation plans for a proposed Space Shuttle-based flight experiment. The test article is an innovative, lightweight solar array concept that uses pop-up, refractive stretched-lens concentrators to achieve a power/mass density of at least 175 W/kg, which is more than three times greater than current capabilities. The flight experiment will validate this new technology to retire the risk associated with its first use in space. The experiment includes structural diagnostic instrumentation to measure the deployment dynamics, static shape, and modes of vibration of the 8-meter-long solar array and several of its lenses. These data will be obtained by photogrammetry using the Shuttle payload-bay video cameras and miniature video cameras on the array. Six accelerometers are also included in the experiment to measure base excitations and small-amplitude tip motions.

Submillimeter Galaxy Surveys with AzTEC

NASA Astrophysics Data System (ADS)

Wilson, Grant W.; Ade, P. A.; Aretxaga, I.; Austermann, J.; Battersby, C.; Bock, J. J.; Glenn, J.; Golwala, S. R.; Haig, D.; Hughes, D. H.; Kang, Y.; Kim, S.; Lowenthal, J.; Mauskopf, P. D.; Perera, T.; Scott, K.; Roberts, C.; Yoon, I.; Yun, M. S.

2006-06-01

We describe a recent large scale survey of the Submillimeter Galaxy (SMG) population by AzTEC, a 144 element bolometer camera, on the 15m diameter James Clerk Maxwell Telescope. From November 2005 to February 2006, over 400 hours of telescope time were spent imaging over 1 square degree of sky with an area weighted target sensitivity of 0.7 mJy rms. Several fields with large multi-wavelength data sets were mapped including the Subaru/XMM-Newton Deep Survey field, the Lockmann Hole, GOODS-N, and a subset of the COSMOS field. In addition we mapped fields spanning a wide range of environments including several regions with known mass over-density. Together this represents the largest/deepest survey of the SMG population. Herein we report on the technical details of the surveys, describe the reduction pipeline, and show preliminary results from a subsection of the survey fields.

Imaging live humans through smoke and flames using far-infrared digital holography.

PubMed

Locatelli, M; Pugliese, E; Paturzo, M; Bianco, V; Finizio, A; Pelagotti, A; Poggi, P; Miccio, L; Meucci, R; Ferraro, P

2013-03-11

The ability to see behind flames is a key challenge for the industrial field and particularly for the safety field. Development of new technologies to detect live people through smoke and flames in fire scenes is an extremely desirable goal since it can save human lives. The latest technologies, including equipment adopted by fire departments, use infrared bolometers for infrared digital cameras that allow users to see through smoke. However, such detectors are blinded by flame-emitted radiation. Here we show a completely different approach that makes use of lensless digital holography technology in the infrared range for successful imaging through smoke and flames. Notably, we demonstrate that digital holography with a cw laser allows the recording of dynamic human-size targets. In this work, easy detection of live, moving people is achieved through both smoke and flames, thus demonstrating the capability of digital holography at 10.6 μm.

Thermoelectric bolometers based on silicon membranes

NASA Astrophysics Data System (ADS)

Varpula, Aapo; Timofeev, Andrey V.; Shchepetov, Andrey; Grigoras, Kestutis; Ahopelto, Jouni; Prunnila, Mika

2017-05-01

State-of-the-art high performance IR sensing and imaging systems utilize highly expensive photodetector technology, which requires exotic and toxic materials and cooling. Cost-effective alternatives, uncooled bolometer detectors, are widely used in commercial long-wave IR (LWIR) systems. Compared to the cooled detectors they are much slower and have approximately an order of magnitude lower detectivity in the LWIR. We present uncooled bolometer technology which is foreseen to be capable of narrowing the gap between the cooled and uncooled technologies. The proposed technology is based on ultra-thin silicon membranes, the thermal conductivity and electrical properties of which can be controlled by membrane thickness and doping, respectively. The thermal signal is transduced into electric voltage using thermocouple consisting of highly-doped n and p type Si beams. Reducing the thickness of the Si membrane improves the performance (i.e. sensitivity and speed) as thermal conductivity and thermal mass of Si membrane decreases with decreasing thickness. Based on experimental data we estimate the performance of these uncooled thermoelectric bolometers.

Fabrication and Test of Large Area Spider-Web Bolometers for CMB Measurements

NASA Astrophysics Data System (ADS)

Biasotti, M.; Ceriale, V.; Corsini, D.; De Gerone, M.; Gatti, F.; Orlando, A.; Pizzigoni, G.

2016-08-01

Detecting the primordial 'B-mode' polarization of the cosmic microwave background is one of the major challenges of modern observational cosmology. Microwave telescopes need sensitive cryogenic bolometers with an overall equivalent noise temperature in the nK range. In this paper, we present the development status of large area (about 1 cm2) spider-web bolometer, which imply additional fabrication challenges. The spider-web is a suspended Si3N4 1 \\upmu m-thick and 8-mm diameter with mesh size of 250 \\upmu m. The thermal sensitive element is a superconducting transition edge sensor (TES) at the center of the bolometer. The first prototype is a Ti-Au TES with transition temperature tuned around 350 mK, new devices will be a Mo-Au bilayer tuned to have a transition temperature of 500 mK. We present the fabrication process with micro-machining techniques from silicon wafer covered with SiO2 - Si3N4 CVD films, 0.3 and 1 \\upmu m- thick, respectively, and preliminary tests.

Developments of Highly Multiplexed, Multi-chroic Pixels for Balloon-Borne Platforms

NASA Astrophysics Data System (ADS)

Aubin, F.; Hanany, S.; Johnson, B. R.; Lee, A.; Suzuki, A.; Westbrook, B.; Young, K.

2018-02-01

We present our work to develop and characterize low thermal conductance bolometers that are part of sinuous antenna multi-chroic pixels (SAMP). We use longer, thinner and meandered bolometer legs to achieve 9 pW/K thermal conductance bolometers. We also discuss the development of inductor-capacitor chips operated at 4 K to extend the multiplexing factor of the frequency domain multiplexing to 105, an increase of 60% compared to the factor currently demonstrated for this readout system. This technology development is motivated by EBEX-IDS, a balloon-borne polarimeter designed to characterize the polarization of foregrounds and to detect the primordial gravity waves through their B-mode signature on the polarization of the cosmic microwave background. EBEX-IDS will operate 20,562 transition edge sensor bolometers spread over 7 frequency bands between 150 and 360 GHz. Balloon and satellite platforms enable observations at frequencies inaccessible from the ground and with higher instantaneous sensitivity. This development improves the readiness of the SAMP and frequency domain readout technologies for future satellite applications.

Development of a Bolometer Detector System for the NIST High Accuracy Infrared Spectrophotometer

PubMed Central

Zong, Y.; Datla, R. U.

1998-01-01

A bolometer detector system was developed for the high accuracy infrared spectrophotometer at the National Institute of Standards and Technology to provide maximum sensitivity, spatial uniformity, and linearity of response covering the entire infrared spectral range. The spatial response variation was measured to be within 0.1 %. The linearity of the detector output was measured over three decades of input power. After applying a simple correction procedure, the detector output was found to deviate less than 0.2 % from linear behavior over this range. The noise equivalent power (NEP) of the bolometer system was 6 × 10−12 W/Hz at the frequency of 80 Hz. The detector output 3 dB roll-off frequency was 200 Hz. The detector output was stable to within ± 0.05 % over a 15 min period. These results demonstrate that the bolometer detector system will serve as an excellent detector for the high accuracy infrared spectrophotometer. PMID:28009364

Comparison of parameters of modern cooled and uncooled thermal cameras

NASA Astrophysics Data System (ADS)

Bareła, Jarosław; Kastek, Mariusz; Firmanty, Krzysztof; Krupiński, Michał

2017-10-01

During the design of a system employing thermal cameras one always faces a problem of choosing the camera types best suited for the task. In many cases such a choice is far from optimal one, and there are several reasons for that. System designers often favor tried and tested solution they are used to. They do not follow the latest developments in the field of infrared technology and sometimes their choices are based on prejudice and not on facts. The paper presents the results of measurements of basic parameters of MWIR and LWIR thermal cameras, carried out in a specialized testing laboratory. The measured parameters are decisive in terms of image quality generated by thermal cameras. All measurements were conducted according to current procedures and standards. However the camera settings were not optimized for a specific test conditions or parameter measurements. Instead the real settings used in normal camera operations were applied to obtain realistic camera performance figures. For example there were significant differences between measured values of noise parameters and catalogue data provided by manufacturers, due to the application of edge detection filters to increase detection and recognition ranges. The purpose of this paper is to provide help in choosing the optimal thermal camera for particular application, answering the question whether to opt for cheaper microbolometer device or apply slightly better (in terms of specifications) yet more expensive cooled unit. Measurements and analysis were performed by qualified personnel with several dozen years of experience in both designing and testing of thermal camera systems with both cooled and uncooled focal plane arrays. Cameras of similar array sizes and optics were compared, and for each tested group the best performing devices were selected.

KSC-01pp1730

NASA Image and Video Library

2001-11-27

KENNEDY SPACE CENTER, Fla. -- In the Vertical Processing Facility, members of the STS-109 crew look over the Solar Array 3 panels that will be replacing Solar Array 2 panels on the Hubble Space Telescope (HST). Trainers, at left, point to the panels while Mission Specialist Nancy Currie (second from right) and Commander Scott Altman (far right) look on. Other crew members are Pilot Duane Carey, Payload Commander John Grunsfeld and Mission Specialists James Newman, Richard Linnehan and Michael Massimino. The other goals of the mission are replacing the Power Control Unit, removing the Faint Object Camera and installing the Advanced Camera for Surveys, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

VizieR Online Data Catalog: ALMA survey of protoplanetary disks in sigma Ori (Ansdell+, 2017)

NASA Astrophysics Data System (ADS)

Ansdell, M.; Williams, J. P.; Manara, C. F.; Miotello, A.; Facchini, S.; van der Marel, N.; Testi, L.; van Dishoeck, E. F.

2017-08-01

Our sample consists of the 92 Young Stellar Objects (YSOs) in σ Orionis with infrared excesses consistent with the presence of a protoplanetary disk. hese sources are identified by cross-matching the Class II and transition disk (TD) candidates from the Spitzer survey of Hernandez et al. 2007 (Cat. J/ApJ/662/1067) with the Mayrit catalog (Caballero 2008, Cat. J/A+A/478/667). Both catalogs are expected to be complete down to the brown dwarf limit. Disk classifications are based on the Spitzer/Infrared Array Camera (IRAC) Spectral Energy Distribution (SED) slope, as described in Hernandez et al. 2007 (Cat. J/ApJ/662/1067). We also include in our sample a Class I disk (source 1153), as it is located near the Spitzer/IRAC color cutoff for Class II disks. Our Band 6 Atacama Large Millimeter/sub-millimeter Array (ALMA) observations were obtained on 2016 July 30 and 31 during Cycle 3 (Project ID: 2015.1.00089.S; PI: Williams). The array configuration used 36 and 37 12m antennas on July 30 and 31, respectively, with baselines of 15-1124m on both runs. The correlator setup included two broadband continuum windows centered on 234.293 and 216.484GHz with bandwidths of 2.000 and 1.875GHz and channel widths of 15.625 and 0.976MHz, respectively. The bandwidth-weighted mean continuum frequency was 225.676GHz (1.33mm). The spectral windows covered the 12CO (230.538GHz), 13CO (220.399GHz), and C18O (219.560GHz) J=2-1 transitions at velocity resolutions of 0.16-0.17km/s. These spectral windows were centered on 230.531, 220.392, and 219.554GHz with bandwidths of 11.719MHz and channel widths of 0.122MHz. On-source integration times were 1.2 minutes per object for an average continuum rms of 0.15mJy/beam (Table1). This sensitivity was based on the James Clerk Maxwell Telescope (JCMT)/Submillimeter Common User Bolometer Array (SCUBA)-2 survey of σ Orionis disks by Williams et al. 2013 (Cat. J/MNRAS/435/1671), who found that stacking their individual non-detections revealed a mean 850μm continuum signal of 1.3mJy at 4σ significance. The sensitivity of our ALMA survey was therefore chosen to provide ~3-4σ detections of such disks at 1.3mm, based on an extrapolation of the 850μm mean signal using a spectral slope of α=2-3. Table1 presents the 1.33mm continuum flux densities and associated uncertainties (F1.33mm). Table2 gives our integrated line fluxes or upper limits. (2 data files).

Dynamical theory of responsivity and response time of a high temperature superconductor photo-thermoelectrical bolometer

NASA Astrophysics Data System (ADS)

Kaila, M. M.

2002-11-01

Dynamical theory of responsivity and response time for an high temperature superconductor (HTSC) photo-thermoelectrical bolometer is analysed in this paper. There is a thermoelectric feedback (TEF) due to the heat transfer from the sensitive area (HTSC-BiSb thermojunction) towards the cold junction of the thermocouple. This is in addition to the normal electrothermal feedback (ETF) between the detector and the substrate, in a photoelectrical bolometer. The two legs of the thermocouple are connected in a parallel geometry configuration. It is seen that TEF can be used in combination with the ETF to enhance responsivity and response time of the detector.

Development of a 1K x 1K GaAs QWIP Far IR Imaging Array

NASA Technical Reports Server (NTRS)

Jhabvala, M.; Choi, K.; Goldberg, A.; La, A.; Gunapala, S.

2003-01-01

In the on-going evolution of GaAs Quantum Well Infrared Photodetectors (QWIPs) we have developed a 1,024 x 1,024 (1K x1K), 8.4-9 microns infrared focal plane array (FPA). This 1 megapixel detector array is a hybrid using the Rockwell TCM 8050 silicon readout integrated circuit (ROIC) bump bonded to a GaAs QWIP array fabricated jointly by engineers at the Goddard Space Flight Center (GSFC) and the Army Research Laboratory (ARL). The finished hybrid is thinned at the Jet Propulsion Lab. Prior to this development the largest format array was a 512 x 640 FPA. We have integrated the 1K x 1K array into an imaging camera system and performed tests over the 40K-90K temperature range achieving BLIP performance at an operating temperature of 76K (f/2 camera system). The GaAs array is relatively easy to fabricate once the superlattice structure of the quantum wells has been defined and grown. The overall arrays costs are currently dominated by the costs associated with the silicon readout since the GaAs array fabrication is based on high yield, well-established GaAs processing capabilities. In this paper we will present the first results of our 1K x 1K QWIP array development including fabrication methodology, test data and our imaging results.

A high-speed trapezoid image sensor design for continuous traffic monitoring at signalized intersection approaches.

DOT National Transportation Integrated Search

2014-10-01

The goal of this project is to monitor traffic flow continuously with an innovative camera system composed of a custom : designed image sensor integrated circuit (IC) containing trapezoid pixel array and camera system that is capable of : intelligent...

Light field geometry of a Standard Plenoptic Camera.

PubMed

Hahne, Christopher; Aggoun, Amar; Haxha, Shyqyri; Velisavljevic, Vladan; Fernández, Juan Carlos Jácome

2014-11-03

The Standard Plenoptic Camera (SPC) is an innovation in photography, allowing for acquiring two-dimensional images focused at different depths, from a single exposure. Contrary to conventional cameras, the SPC consists of a micro lens array and a main lens projecting virtual lenses into object space. For the first time, the present research provides an approach to estimate the distance and depth of refocused images extracted from captures obtained by an SPC. Furthermore, estimates for the position and baseline of virtual lenses which correspond to an equivalent camera array are derived. On the basis of paraxial approximation, a ray tracing model employing linear equations has been developed and implemented using Matlab. The optics simulation tool Zemax is utilized for validation purposes. By designing a realistic SPC, experiments demonstrate that a predicted image refocusing distance at 3.5 m deviates by less than 11% from the simulation in Zemax, whereas baseline estimations indicate no significant difference. Applying the proposed methodology will enable an alternative to the traditional depth map acquisition by disparity analysis.

Advanced imaging research and development at DARPA

NASA Astrophysics Data System (ADS)

Dhar, Nibir K.; Dat, Ravi

2012-06-01

Advances in imaging technology have huge impact on our daily lives. Innovations in optics, focal plane arrays (FPA), microelectronics and computation have revolutionized camera design. As a result, new approaches to camera design and low cost manufacturing is now possible. These advances are clearly evident in visible wavelength band due to pixel scaling, improvements in silicon material and CMOS technology. CMOS cameras are available in cell phones and many other consumer products. Advances in infrared imaging technology have been slow due to market volume and many technological barriers in detector materials, optics and fundamental limits imposed by the scaling laws of optics. There is of course much room for improvements in both, visible and infrared imaging technology. This paper highlights various technology development projects at DARPA to advance the imaging technology for both, visible and infrared. Challenges and potentials solutions are highlighted in areas related to wide field-of-view camera design, small pitch pixel, broadband and multiband detectors and focal plane arrays.

KSC01pd1736

NASA Image and Video Library

2001-11-26

KENNEDY SPACE CENTER, Fla. -- A piece of equipment for Hubble Space Telescope Servicing mission is moved inside Hangar AE, Cape Canaveral. In the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

KSC-01pp1758

NASA Image and Video Library

2001-11-29

KENNEDY SPACE CENTER, Fla. -- In Hangar A&E, workers watch as an overhead crane lifts the Advanced Camera for Surveys out of its transportation container. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

KSC01pd1735

NASA Image and Video Library

2001-11-26

KENNEDY SPACE CENTER, Fla. - A piece of equipment for Hubble Space Telescope Servicing mission arrives at Hangar AE, Cape Canaveral. Inside the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

An experimental study of antireflective coatings in Ge light detectors for scintillating bolometers

NASA Astrophysics Data System (ADS)

Mancuso, M.; Beeman, J. W.; Giuliani, A.; Dumoulin, L.; Olivieri, E.; Pessina, G.; Plantevin, O.; Rusconi, C.; Tenconi, M.

2014-01-01

Luminescent bolometers are double-readout devices able to measure simultaneously the phonon and the light yields after a particle interaction in the detector. This operation allows in some cases to tag the type of the interacting quantum, crucial issue for background control in rare event experiments such as the search for neutrinoless double beta decay and for interactions of particle dark matter candidates. The light detectors used in the LUCIFER and LUMINEU searches (projects aiming at the study of the double beta interesting candidates 82Se and 100Mo using ZnSe and ZnMoO4 scintillating bolometers) consist of hyper-pure Ge thin slabs equipped with NTD thermistors. A substantial sensitivity improvement of the Ge light detectors can be obtained applying a proper anti-reflective coatings on the Ge side exposed to the luminescent bolometer. The present paper deals with the investigation of this aspect, proving and quantifying the positive effect of a SiO2 and a SiO coating and setting the experimental bases for future tests of other coating materials. The results confirm that an appropriate coating procedure helps in improving the sensitivity of bolometric light detectors by an important factor (in the range 20% - 35%) and needs to be included in the recipe for the development of an optimized radio-pure scintillating bolometer.

Transition-Edge Hot-Electron Microbolometers for Millimeter and Submillimeter Astrophysics

NASA Technical Reports Server (NTRS)

Hsieh, Wen-Ting; Stevenson, Thomas; U-yen, Kongpop; Wollack, Edward; Barrentine, Emily

2014-01-01

The millimeter and the submillimeter wavelengths of the electromagnetic spectrum hold a wealth of information about the evolution of the universe. In particular, cosmic microwave background (CMB) radiation and its polarization carry the oldest information in the universe, and provide the best test of the inflationary paradigm available to astronomy today. Detecting gravity waves through their imprint on the CMB polarization would have extraordinary repercussions for cosmology and physics. A transition-edge hot-electron micro - bolometer (THM) consists of a superconducting bilayer transition-edge sensor (TES) with a thin-film absorber. Unlike traditional monolithic bolometers that make use of micromachined structures, the THM em ploys the decoupling between electrons and phonons at millikelvin temperatures to provide thermal isolation. The devices are fabricated photolithographically and are easily integrated with antennas via microstrip transmission lines, and with SQUID (superconducting quantum interference device) readouts. The small volume of the absorber and TES produces a short thermal time constant that facilitates rapid sky scanning. The THM consists of a thin-film metal absorber overlapping a superconducting TES. The absorber forms the termination of a superconducting microstripline that carries RF power from an antenna. The purpose of forming a separate absorber and TES is to allow flexibility in the optimization of the two components. In particular, the absorbing film's impedance can be chosen to match the antenna, while the TES impedance can be chosen to match to the readout SQUID amplifier. This scheme combines the advantages of the TES with the advantages of planar millimeter-wave transmission line circuits. Antenna-coupling to the detectors via planar transmission lines allows the detector dimensions to be much smaller than a wavelength, so the technique can be extended across the entire microwave, millimeter, and submillimeter wavelength ranges. The circuits are fabricated using standard microlithographic techniques and are compatible with uniform, large array formats. Unlike traditional monolithic bolometers that make use of micromachined structures, the THM employs the decoupling between electrons and phonons at millikelvin temperatures to provide thermal isolation. There is no fragile membrane in the structure for thermal isolation, which improves the fabrication yield.

The electronics system for the LBNL positron emission mammography (PEM) camera

NASA Astrophysics Data System (ADS)

Moses, W. W.; Young, J. W.; Baker, K.; Jones, W.; Lenox, M.; Ho, M. H.; Weng, M.

2001-06-01

Describes the electronics for a high-performance positron emission mammography (PEM) camera. It is based on the electronics for a human brain positron emission tomography (PET) camera (the Siemens/CTI HRRT), modified to use a detector module that incorporates a photodiode (PD) array. An application-specified integrated circuit (ASIC) services the photodetector (PD) array, amplifying its signal and identifying the crystal of interaction. Another ASIC services the photomultiplier tube (PMT), measuring its output and providing a timing signal. Field-programmable gate arrays (FPGAs) and lookup RAMs are used to apply crystal-by-crystal correction factors and measure the energy deposit and the interaction depth (based on the PD/PMT ratio). Additional FPGAs provide event multiplexing, derandomization, coincidence detection, and real-time rebinning. Embedded PC/104 microprocessors provide communication, real-time control, and configure the system. Extensive use of FPGAs make the overall design extremely flexible, allowing many different functions (or design modifications) to be realized without hardware changes. Incorporation of extensive onboard diagnostics, implemented in the FPGAs, is required by the very high level of integration and density achieved by this system.

CMOS Camera Array With Onboard Memory

NASA Technical Reports Server (NTRS)

Gat, Nahum

2009-01-01

A compact CMOS (complementary metal oxide semiconductor) camera system has been developed with high resolution (1.3 Megapixels), a USB (universal serial bus) 2.0 interface, and an onboard memory. Exposure times, and other operating parameters, are sent from a control PC via the USB port. Data from the camera can be received via the USB port and the interface allows for simple control and data capture through a laptop computer.

Solid State Television Camera (CID)

NASA Technical Reports Server (NTRS)

Steele, D. W.; Green, W. T.

1976-01-01

The design, development and test are described of a charge injection device (CID) camera using a 244x248 element array. A number of video signal processing functions are included which maximize the output video dynamic range while retaining the inherently good resolution response of the CID. Some of the unique features of the camera are: low light level performance, high S/N ratio, antiblooming, geometric distortion, sequential scanning and AGC.

High-speed line-scan camera with digital time delay integration

NASA Astrophysics Data System (ADS)

Bodenstorfer, Ernst; Fürtler, Johannes; Brodersen, Jörg; Mayer, Konrad J.; Eckel, Christian; Gravogl, Klaus; Nachtnebel, Herbert

2007-02-01

Dealing with high-speed image acquisition and processing systems, the speed of operation is often limited by the amount of available light, due to short exposure times. Therefore, high-speed applications often use line-scan cameras, based on charge-coupled device (CCD) sensors with time delayed integration (TDI). Synchronous shift and accumulation of photoelectric charges on the CCD chip - according to the objects' movement - result in a longer effective exposure time without introducing additional motion blur. This paper presents a high-speed color line-scan camera based on a commercial complementary metal oxide semiconductor (CMOS) area image sensor with a Bayer filter matrix and a field programmable gate array (FPGA). The camera implements a digital equivalent to the TDI effect exploited with CCD cameras. The proposed design benefits from the high frame rates of CMOS sensors and from the possibility of arbitrarily addressing the rows of the sensor's pixel array. For the digital TDI just a small number of rows are read out from the area sensor which are then shifted and accumulated according to the movement of the inspected objects. This paper gives a detailed description of the digital TDI algorithm implemented on the FPGA. Relevant aspects for the practical application are discussed and key features of the camera are listed.

Measurements of the optical performance of bolometers for SPICA/SAFARI

NASA Astrophysics Data System (ADS)

Audley, Michael D.; de Lange, Gert; Gao, Jian-Rong; Khosropanah, Pourya; Ridder, Marcel; Ferrari, Lorenza; Laauwen, Wouter M.; Ranjan, Manisha; Mauskopf, Philip D.; Morozov, Dmitry; Trappe, Neil A.

2012-09-01

We have measured the optical response of detectors designed for SAFARI, the far-infrared imaging spectrometer for the SPICA satellite. To take advantage of SPICA's cooled optics, SAFARI’s three bolometer arrays are populated with extremely sensitive (NEP~2×10-19 W/√Hz) transition edge sensors with a transition temperature close to 100 mK. The extreme sensitivity and low saturation power (~4 fW) of SAFARI’s detectors present challenges to characterizing them. We have therefore built up an ultra-low background test facility with a cryogen-free high-capacity dilution refrigerator, paying careful attention to stray-light exclusion. Our use of a pulse-tube cooler to pre-cool the dilution refrigerator required that the SAFARI Detector System Test Facility provide a high degree electrical, magnetic, and mechanical isolation for the detectors. We have carefully characterized the performance of the test facility in terms of background power loading. The test facility has been designed to be flexible and easily reconfigurable with internal illuminators that allow us to characterize the optical response of the detectors. We describe the test facility and some of the steps we took to create an ultra-low background test environment. We have measured the optical response of two detectors designed for SAFARI’s short-wave wavelength band in combination with a spherical backshort and conical feedhorn. We find an overall optical efficiency of 40% for both, compared with an ideal-case predicted optical efficiency of 66%.

Detectors for the Atacama B-mode Search experiment

NASA Astrophysics Data System (ADS)

Appel, John William

Inflation is the leading theory for explaining the initial conditions that brought about our homogeneous and isotropic Universe. It predicts the presence of gravitational waves in the early Universe, which implant a characteristic B-mode polarization pattern on the Cosmic Microwave Background (CMB). The Atacama B-mode Search (ABS) experiment is a polarimeter observing from Cerro Toco (located in the Atacama desert of Chile at an altitude of 5190 m), searching for the yet undetected B-mode signal. ABS carries 480 superconducting Transition Edge Sensor (TES) Bolometers that couple 150 GHz radiation via planar Ortho-Mode Transducers (OMTs) mounted at the output of corrugated feedhorns. The feedhorn beam is projected onto the sky through crossed Dragonian reflectors, a set of reflective and absorptive filters, and a rotating Half Wave Plate (HWP) that modulates any polarized sky signal at 10.2 Hz. The bolometers are cooled to 300 mK by a He3-He4 adsorption fridge system backed by pulse tubes. The reflectors are located within the 4 K cavity of the cryostat, while the HWP is mounted on frictionless air bearings above the cryostat window. This thesis discusses the development and construction of the ABS detector focal plane, and presents results of its performance in the field through August 2012. The ABS detector array sensitivity of 31 μKs 1/2, together with the experiment's unique set of systematic controls, and expected multi-year integration time, could detect a B-mode signal with tensor to scalar ratio r ˜ 0.1.

Magnetic Sensitivity of AlMn TESes and Shielding Considerations for Next-Generation CMB Surveys

NASA Astrophysics Data System (ADS)

Vavagiakis, E. M.; Henderson, S. W.; Zheng, K.; Cho, H.-M.; Cothard, N. F.; Dober, B.; Duff, S. M.; Gallardo, P. A.; Hilton, G.; Hubmayr, J.; Irwin, K. D.; Koopman, B. J.; Li, D.; Nati, F.; Niemack, M. D.; Reintsema, C. D.; Simon, S.; Stevens, J. R.; Suzuki, A.; Westbrook, B.

2018-05-01

In the next decade, new ground-based cosmic microwave background (CMB) experiments such as Simons Observatory, CCAT-prime, and CMB-S4 will increase the number of detectors observing the CMB by an order of magnitude or more, dramatically improving our understanding of cosmology and astrophysics. These projects will deploy receivers with as many as hundreds of thousands of transition edge sensor (TES) bolometers coupled to superconducting quantum interference device (SQUID)-based readout systems. It is well known that superconducting devices such as TESes and SQUIDs are sensitive to magnetic fields. However, the effects of magnetic fields on TESes are not easily predicted due to the complex behavior of the superconducting transition, which motivates direct measurements of the magnetic sensitivity of these devices. We present comparative four-lead measurements of the critical temperature versus applied magnetic field of AlMn TESes varying in geometry, doping, and leg length, including Advanced ACT and POLARBEAR-2/Simons Array bolometers. MoCu ACTPol TESes are also tested and are found to be more sensitive to magnetic fields than the AlMn devices. We present an observation of weak-link-like behavior in AlMn TESes at low critical currents. We also compare measurements of magnetic sensitivity for time division multiplexing SQUIDs and frequency division multiplexing microwave (μ MUX) rf-SQUIDs. We discuss the implications of our measurements on the magnetic shielding required for future experiments that aim to map the CMB to near-fundamental limits.

Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

NASA Technical Reports Server (NTRS)

Denis, K. L.; Ali, A.; Appel, J.; Bennett, C. L.; Chang, M. P.; Chuss, D. T.; Colazo, F. A.; Costen, N.; Essinger-Hileman, T.; Hu, R.;

Fabrication of Feedhorn-Coupled Transition Edge Sensor Arrays for Measurement of the Cosmic Microwave Background Polarization

NASA Technical Reports Server (NTRS)

Denis, Kevin L.; Aamir, A.; Bennett, C. L.; Chang, M. P.; Chuss, D. T.; Colazo, F. A.; Costen, N.; Essinger-Hileman, T.; Hu, R.; Marriage, T.;

A 1.5 THz hot-electron bolometer mixer operated by a planar diode based local oscillator

NASA Technical Reports Server (NTRS)

Tong, C. Y. E.; Meledin, D.; Blundell, R.; Erickson, N.; Mehdi, I.; Goltsman, G.

2003-01-01

We have developed a 1.5 THz superconducting NbN Hot-Electron Bolometer mixer. It is oprated by an all-solid-state Local Oscillator comprising of a cascade of 4 planar doublers following an MMIC based W-band power amplifier.

Fabrication of Pop-up Detector Arrays on Si Wafers

NASA Technical Reports Server (NTRS)

Li, Mary J.; Allen, Christine A.; Gordon, Scott A.; Kuhn, Jonathan L.; Mott, David B.; Stahle, Caroline K.; Wang, Liqin L.

1999-01-01

High sensitivity is a basic requirement for a new generation of thermal detectors. To meet the requirement, close-packed, two-dimensional silicon detector arrays have been developed in NASA Goddard Space Flight Center. The goal of the task is to fabricate detector arrays configured with thermal detectors such as infrared bolometers and x-ray calorimeters to use in space fliGht missions. This paper focuses on the fabrication and the mechanical testing of detector arrays in a 0.2 mm pixel size, the smallest pop-up detectors being developed so far. These array structures, nicknamed "PUDS" for "Pop-Up Detectors", are fabricated on I pm thick, single-crystal, silicon membranes. Their designs have been refined so we can utilize the flexibility of thin silicon films by actually folding the silicon membranes to 90 degrees in order to obtain close-packed two-dimensional arrays. The PUD elements consist of a detector platform and two legs for mechanical support while also serving as electrical and thermal paths. Torsion bars and cantilevers connecting the detector platform to the legs provide additional flexures for strain relief. Using micro-electromechanical structure (MEMS) fabrication techniques, including photolithography, anisotropic chemical etching, reactive-ion etching, and laser dicing, we have fabricated PLTD detector arrays of fourteen designs with a variation of four parameters including cantilever length, torsion bar length and width, and leg length. Folding tests were conducted to test mechanical stress distribution for the array structures. We obtained folding yields and selected optimum design parameters to reach minimal stress levels. Computer simulation was also employed to verify mechanical behaviors of PUDs in the folding process. In addition, scanning electron microscopy was utilized to examine the flatness of detectors and the alignment of detector pixels in arrays. The fabrication of thermistors and heaters on the pop-up detectors is under way, preparing us for the next step of the experiment, the thermal test.

Latest improvements in microbolometer thin film packaging: paving the way for low-cost consumer applications

NASA Astrophysics Data System (ADS)

Yon, J. J.; Dumont, G.; Goudon, V.; Becker, S.; Arnaud, A.; Cortial, S.; Tisse, C. L.

2014-06-01

Silicon-based vacuum packaging is a key enabling technology for achieving affordable uncooled Infrared Focal Plane Arrays (IRFPA) required by a promising mass market that shows momentum for some extensive consumer applications, such as automotive driving assistance, smart presence localization and building management. Among the various approaches studied worldwide, CEA, LETI in partnership with ULIS is committed to the development of a unique technology referred to as PLP (Pixel Level Packaging). In this PLP technology, each bolometer pixel is sealed under vacuum using a transparent thin film deposition on wafer. PLP operates as an array of hermetic micro caps above the focal plane, each enclosing a single microbolometer. In continuation of our on-going studies on PLP for regular QVGA IRFPAs, this paper emphasizes on the innate scalability of the technology which was successfully demonstrated through the development of an 80 × 80 pixel IRFPA. The relevance of the technology with regard to the two formats is discussed, considering both performance and cost issues. We show that the suboptimal fill factor inherent to the PLP arrangement is not so critical when considering smaller arrays preferably fitted for consumer applications. The discussion is supported with the electro-optical performance measurements of the PLP-based 80×80 demonstrator.

INFRARED LUMINOSITIES AND DUST PROPERTIES OF z approx 2 DUST-OBSCURED GALAXIES

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

Bussmann, R. S.; Dey, Arjun; Jannuzi, B. T.

We present SHARC-II 350 mum imaging of twelve 24 mum bright (F{sub 24m}u{sub m} > 0.8 mJy) Dust-Obscured Galaxies (DOGs) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) 1 mm imaging of a subset of two DOGs. These objects are selected from the Booetes field of the NOAO Deep Wide-Field Survey. Detections of four DOGs at 350 mum imply infrared (IR) luminosities which are consistent to within a factor of 2 of expectations based on a warm-dust spectral energy distribution (SED) scaled to the observed 24 mum flux density. The 350 mum upper limits for the 8 non-detected DOGsmore » are consistent with both Mrk 231 and M82 (warm-dust SEDs), but exclude cold dust (Arp 220) SEDs. The two DOGs targeted at 1 mm were not detected in our CARMA observations, placing strong constraints on the dust temperature: T{sub dust} > 35-60 K. Assuming these dust properties apply to the entire sample, we find dust masses of approx3 x 10{sup 8} M{sub sun}. In comparison to other dusty z approx 2 galaxy populations such as submillimeter galaxies (SMGs) and other Spitzer-selected high-redshift sources, this sample of DOGs has higher IR luminosities (2 x 10{sup 13} L{sub sun} versus 6 x 10{sup 12} L{sub sun} for the other galaxy populations) that are driven by warmer dust temperatures (>35-60 K versus approx30 K) and lower inferred dust masses (3 x 10{sup 8} M{sub sun} versus 3 x 10{sup 9} M{sub sun}). Wide-field Herschel and Submillimeter Common-User Bolometer Array-2 surveys should be able to detect hundreds of these power-law-dominated DOGs. We use the existing Hubble Space Telescope and Spitzer/InfraRed Array Camera data to estimate stellar masses of these sources and find that the stellar to gas mass ratio may be higher in our 24 mum bright sample of DOGs than in SMGs and other Spitzer-selected sources. Although much larger sample sizes are needed to provide a definitive conclusion, the data are consistent with an evolutionary trend in which the formation of massive galaxies at z approx 2 involves a submillimeter bright, cold-dust, and star-formation-dominated phase followed by a 24 mum bright, warm-dust and AGN-dominated phase.« less

Object recognition through turbulence with a modified plenoptic camera

NASA Astrophysics Data System (ADS)

Wu, Chensheng; Ko, Jonathan; Davis, Christopher

2015-03-01

Atmospheric turbulence adds accumulated distortion to images obtained by cameras and surveillance systems. When the turbulence grows stronger or when the object is further away from the observer, increasing the recording device resolution helps little to improve the quality of the image. Many sophisticated methods to correct the distorted images have been invented, such as using a known feature on or near the target object to perform a deconvolution process, or use of adaptive optics. However, most of the methods depend heavily on the object's location, and optical ray propagation through the turbulence is not directly considered. Alternatively, selecting a lucky image over many frames provides a feasible solution, but at the cost of time. In our work, we propose an innovative approach to improving image quality through turbulence by making use of a modified plenoptic camera. This type of camera adds a micro-lens array to a traditional high-resolution camera to form a semi-camera array that records duplicate copies of the object as well as "superimposed" turbulence at slightly different angles. By performing several steps of image reconstruction, turbulence effects will be suppressed to reveal more details of the object independently (without finding references near the object). Meanwhile, the redundant information obtained by the plenoptic camera raises the possibility of performing lucky image algorithmic analysis with fewer frames, which is more efficient. In our work, the details of our modified plenoptic cameras and image processing algorithms will be introduced. The proposed method can be applied to coherently illuminated object as well as incoherently illuminated objects. Our result shows that the turbulence effect can be effectively suppressed by the plenoptic camera in the hardware layer and a reconstructed "lucky image" can help the viewer identify the object even when a "lucky image" by ordinary cameras is not achievable.

Architecture and settings optimization procedure of a TES frequency domain multiplexed readout firmware

NASA Astrophysics Data System (ADS)

Clenet, A.; Ravera, L.; Bertrand, B.; den Hartog, R.; Jackson, B.; van Leeuwen, B.-J.; van Loon, D.; Parot, Y.; Pointecouteau, E.; Sournac, A.

2014-11-01

IRAP is developing the readout electronics of the SPICA-SAFARI's TES bolometer arrays. Based on the frequency domain multiplexing technique the readout electronics provides the AC-signals to voltage-bias the detectors; it demodulates the data; and it computes a feedback to linearize the detection chain. The feedback is computed with a specific technique, so called baseband feedback (BBFB) which ensures that the loop is stable even with long propagation and processing delays (i.e. several μ s) and with fast signals (i.e. frequency carriers of the order of 5 MHz). To optimize the power consumption we took advantage of the reduced science signal bandwidth to decouple the signal sampling frequency and the data processing rate. This technique allowed a reduction of the power consumption of the circuit by a factor of 10. Beyond the firmware architecture the optimization of the instrument concerns the characterization routines and the definition of the optimal parameters. Indeed, to operate an array TES one has to properly define about 21000 parameters. We defined a set of procedures to automatically characterize these parameters and find out the optimal settings.

A compact lightweight Earth horizon sensor using an uncooled infrared bolometer

NASA Astrophysics Data System (ADS)

Marchese, Linda E.; Thomas, Paul; Pope, Timothy D.; Asselin, Daniel; Jerominek, Hubert

2007-06-01

A compact, lightweight Earth horizon sensor has been designed based on uncooled infrared microbolometer array technology developed at INO. The design has been optimized for use on small satellites in Low Earth Orbits. The sensor may be used either as an attitude sensor or as an atmospheric limb detector. Various configurations may be implemented for both spinning and 3-axis stabilized satellites. The core of the sensor is the microbolometer focal plane array equipped with 256 x 1 VO x thermistor pixels with a pitch of 52 μm. The optics consists of a single Zinc Selenide lens with a focal length of 39.7 mm. The system's F-number is 3.8 and the detector limited Noise Equivalent Temperature Difference is estimated to be 0.75 K at 300 K for the 14 - 16 μm wavelength range. A single-sensor configuration will have a mass of less than 300g, a volume of 125 cm 3 and a power consumption of 600 mW, making it well-suited for small satellite missions.

Design and Fabrication of TES Detector Modules for the TIME-Pilot [CII] Intensity Mapping Experiment

NASA Astrophysics Data System (ADS)

Hunacek, J.; Bock, J.; Bradford, C. M.; Bumble, B.; Chang, T.-C.; Cheng, Y.-T.; Cooray, A.; Crites, A.; Hailey-Dunsheath, S.; Gong, Y.; Kenyon, M.; Koch, P.; Li, C.-T.; O'Brient, R.; Shirokoff, E.; Shiu, C.; Staniszewski, Z.; Uzgil, B.; Zemcov, M.

2016-08-01

We are developing a series of close-packed modular detector arrays for TIME-Pilot, a new mm-wavelength grating spectrometer array that will map the intensity fluctuations of the redshifted 157.7 \\upmu m emission line of singly ionized carbon ([CII]) from redshift z ˜ 5 to 9. TIME-Pilot's two banks of 16 parallel-plate waveguide spectrometers (one bank per polarization) will have a spectral range of 183-326 GHz and a resolving power of R ˜ 100. The spectrometers use a curved diffraction grating to disperse and focus the light on a series of output arcs, each sampled by 60 transition edge sensor (TES) bolometers with gold micro-mesh absorbers. These low-noise detectors will be operated from a 250 mK base temperature and are designed to have a background-limited NEP of {˜ }10^{-17} mathrm {W}/mathrm {Hz}^{1/2}. This proceeding presents an overview of the detector design in the context of the TIME-Pilot instrument. Additionally, a prototype detector module produced at the Microdevices Laboratory at JPL is shown.

Space infrared telescope facility wide field and diffraction limited array camera (IRAC)

NASA Technical Reports Server (NTRS)

Fazio, G. G.

1986-01-01

IRAC focal plane detector technology was developed and studies of alternate focal plane configurations were supported. While any of the alternate focal planes under consideration would have a major impact on the Infrared Array Camera, it was possible to proceed with detector development and optical analysis research based on the proposed design since, to a large degree, the studies undertaken are generic to any SIRTF imaging instrument. Development of the proposed instrument was also important in a situation in which none of the alternate configurations has received the approval of the Science Working Group.

Lunar UV-visible-IR mapping interferometric spectrometer

NASA Technical Reports Server (NTRS)

Smith, W. Hayden; Haskin, L.; Korotev, R.; Arvidson, R.; Mckinnon, W.; Hapke, B.; Larson, S.; Lucey, P.

1992-01-01

Ultraviolet-visible-infrared mapping digital array scanned interferometers for lunar compositional surveys was developed. The research has defined a no-moving-parts, low-weight and low-power, high-throughput, and electronically adaptable digital array scanned interferometer that achieves measurement objectives encompassing and improving upon all the requirements defined by the LEXSWIG for lunar mineralogical investigation. In addition, LUMIS provides a new, important, ultraviolet spectral mapping, high-spatial-resolution line scan camera, and multispectral camera capabilities. An instrument configuration optimized for spectral mapping and imaging of the lunar surface and provide spectral results in support of the instrument design are described.

Smart-phone based computational microscopy using multi-frame contact imaging on a fiber-optic array.

PubMed

Navruz, Isa; Coskun, Ahmet F; Wong, Justin; Mohammad, Saqib; Tseng, Derek; Nagi, Richie; Phillips, Stephen; Ozcan, Aydogan

2013-10-21

We demonstrate a cellphone based contact microscopy platform, termed Contact Scope, which can image highly dense or connected samples in transmission mode. Weighing approximately 76 grams, this portable and compact microscope is installed on the existing camera unit of a cellphone using an opto-mechanical add-on, where planar samples of interest are placed in contact with the top facet of a tapered fiber-optic array. This glass-based tapered fiber array has ~9 fold higher density of fiber optic cables on its top facet compared to the bottom one and is illuminated by an incoherent light source, e.g., a simple light-emitting-diode (LED). The transmitted light pattern through the object is then sampled by this array of fiber optic cables, delivering a transmission image of the sample onto the other side of the taper, with ~3× magnification in each direction. This magnified image of the object, located at the bottom facet of the fiber array, is then projected onto the CMOS image sensor of the cellphone using two lenses. While keeping the sample and the cellphone camera at a fixed position, the fiber-optic array is then manually rotated with discrete angular increments of e.g., 1-2 degrees. At each angular position of the fiber-optic array, contact images are captured using the cellphone camera, creating a sequence of transmission images for the same sample. These multi-frame images are digitally fused together based on a shift-and-add algorithm through a custom-developed Android application running on the smart-phone, providing the final microscopic image of the sample, visualized through the screen of the phone. This final computation step improves the resolution and also removes spatial artefacts that arise due to non-uniform sampling of the transmission intensity at the fiber optic array surface. We validated the performance of this cellphone based Contact Scope by imaging resolution test charts and blood smears.

Smart-phone based computational microscopy using multi-frame contact imaging on a fiber-optic array

PubMed Central

Navruz, Isa; Coskun, Ahmet F.; Wong, Justin; Mohammad, Saqib; Tseng, Derek; Nagi, Richie; Phillips, Stephen; Ozcan, Aydogan

2013-01-01

We demonstrate a cellphone based contact microscopy platform, termed Contact Scope, which can image highly dense or connected samples in transmission mode. Weighing approximately 76 grams, this portable and compact microscope is installed on the existing camera unit of a cellphone using an opto-mechanical add-on, where planar samples of interest are placed in contact with the top facet of a tapered fiber-optic array. This glass-based tapered fiber array has ∼9 fold higher density of fiber optic cables on its top facet compared to the bottom one and is illuminated by an incoherent light source, e.g., a simple light-emitting-diode (LED). The transmitted light pattern through the object is then sampled by this array of fiber optic cables, delivering a transmission image of the sample onto the other side of the taper, with ∼3× magnification in each direction. This magnified image of the object, located at the bottom facet of the fiber array, is then projected onto the CMOS image sensor of the cellphone using two lenses. While keeping the sample and the cellphone camera at a fixed position, the fiber-optic array is then manually rotated with discrete angular increments of e.g., 1-2 degrees. At each angular position of the fiber-optic array, contact images are captured using the cellphone camera, creating a sequence of transmission images for the same sample. These multi-frame images are digitally fused together based on a shift-and-add algorithm through a custom-developed Android application running on the smart-phone, providing the final microscopic image of the sample, visualized through the screen of the phone. This final computation step improves the resolution and also gets rid of spatial artefacts that arise due to non-uniform sampling of the transmission intensity at the fiber optic array surface. We validated the performance of this cellphone based Contact Scope by imaging resolution test charts and blood smears. PMID:23939637

Active terahertz imaging with Ne indicator lamp detector arrays

NASA Astrophysics Data System (ADS)

Kopeika, N. S.; Abramovich, A.; Yadid-Pecht, O.; Yitzhaky, Y.

2009-08-01

The advantages of terahertz (THz) imaging are well known. They penetrate well most non-conducting media and there are no known biological hazards, This makes such imaging systems important for homeland security, as they can be used to image concealed objects and often into rooms or buildings from the outside. There are also biomedical applications that are arising. Unfortunately, THz imaging is quite expensive, especially for real time systems, largely because of the price of the detector. Bolometers and pyroelectric detectors can each easily cost at least hundreds of dollars if not more, thus making focal plane arrays of them quite expensive. We have found that common miniature commercial neon indicator lamps costing typically about 30 cents each exhibit high sensitivity to THz radiation [1-3], with microsecond order rise times, thus making them excellent candidates for such focal plane arrays. NEP is on the order of 10-10 W/Hz1/2. Significant improvement of detection performance is expected when heterodyne detection is used Efforts are being made to develop focal plane array imagers using such devices at 300 GHz. Indeed, preliminary images using 4x4 arrays have already been obtained. An 8x8 VLSI board has been developed and is presently being tested. Since no similar imaging systems have been developed previously, there are many new problems to be solved with such a novel and unconventional imaging system. These devices act as square law detectors, with detected signal proportional to THz power. This allows them to act as mixers in heterodyne detection, thus allowing NEP to be reduced further by almost two orders of magnitude. Plans are to expand the arrays to larger sizes, and to employ super resolution techniques to improve image quality beyond that ordinarily obtainable at THz frequencies.

Concept of electro-optical sensor module for sniper detection system

NASA Astrophysics Data System (ADS)

Trzaskawka, Piotr; Dulski, Rafal; Kastek, Mariusz

2010-10-01

The paper presents an initial concept of the electro-optical sensor unit for sniper detection purposes. This unit, comprising of thermal and daylight cameras, can operate as a standalone device but its primary application is a multi-sensor sniper and shot detection system. Being a part of a larger system it should contribute to greater overall system efficiency and lower false alarm rate thanks to data and sensor fusion techniques. Additionally, it is expected to provide some pre-shot detection capabilities. Generally acoustic (or radar) systems used for shot detection offer only "after-the-shot" information and they cannot prevent enemy attack, which in case of a skilled sniper opponent usually means trouble. The passive imaging sensors presented in this paper, together with active systems detecting pointed optics, are capable of detecting specific shooter signatures or at least the presence of suspected objects in the vicinity. The proposed sensor unit use thermal camera as a primary sniper and shot detection tool. The basic camera parameters such as focal plane array size and type, focal length and aperture were chosen on the basis of assumed tactical characteristics of the system (mainly detection range) and current technology level. In order to provide costeffective solution the commercially available daylight camera modules and infrared focal plane arrays were tested, including fast cooled infrared array modules capable of 1000 fps image acquisition rate. The daylight camera operates as a support, providing corresponding visual image, easier to comprehend for a human operator. The initial assumptions concerning sensor operation were verified during laboratory and field test and some example shot recording sequences are presented.

Camera Development for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Moncada, Roberto Jose

2017-01-01

With the Cherenkov Telescope Array (CTA), the very-high-energy gamma-ray universe, between 30 GeV and 300 TeV, will be probed at an unprecedented resolution, allowing deeper studies of known gamma-ray emitters and the possible discovery of new ones. This exciting project could also confirm the particle nature of dark matter by looking for the gamma rays produced by self-annihilating weakly interacting massive particles (WIMPs). The telescopes will use the imaging atmospheric Cherenkov technique (IACT) to record Cherenkov photons that are produced by the gamma-ray induced extensive air shower. One telescope design features dual-mirror Schwarzschild-Couder (SC) optics that allows the light to be finely focused on the high-resolution silicon photomultipliers of the camera modules starting from a 9.5-meter primary mirror. Each camera module will consist of a focal plane module and front-end electronics, and will have four TeV Array Readout with GSa/s Sampling and Event Trigger (TARGET) chips, giving them 64 parallel input channels. The TARGET chip has a self-trigger functionality for readout that can be used in higher logic across camera modules as well as across individual telescopes, which will each have 177 camera modules. There will be two sites, one in the northern and the other in the southern hemisphere, for full sky coverage, each spanning at least one square kilometer. A prototype SC telescope is currently under construction at the Fred Lawrence Whipple Observatory in Arizona. This work was supported by the National Science Foundation's REU program through NSF award AST-1560016.

Quantitative analysis of the improvement in omnidirectional maritime surveillance and tracking due to real-time image enhancement

NASA Astrophysics Data System (ADS)

de Villiers, Jason P.; Bachoo, Asheer K.; Nicolls, Fred C.; le Roux, Francois P. J.

2011-05-01

Tracking targets in a panoramic image is in many senses the inverse problem of tracking targets with a narrow field of view camera on a pan-tilt pedestal. In a narrow field of view camera tracking a moving target, the object is constant and the background is changing. A panoramic camera is able to model the entire scene, or background, and those areas it cannot model well are the potential targets and typically subtended far fewer pixels in the panoramic view compared to the narrow field of view. The outputs of an outward staring array of calibrated machine vision cameras are stitched into a single omnidirectional panorama and used to observe False Bay near Simon's Town, South Africa. A ground truth data-set was created by geo-aligning the camera array and placing a differential global position system receiver on a small target boat thus allowing its position in the array's field of view to be determined. Common tracking techniques including level-sets, Kalman filters and particle filters were implemented to run on the central processing unit of the tracking computer. Image enhancement techniques including multi-scale tone mapping, interpolated local histogram equalisation and several sharpening techniques were implemented on the graphics processing unit. An objective measurement of each tracking algorithm's robustness in the presence of sea-glint, low contrast visibility and sea clutter - such as white caps is performed on the raw recorded video data. These results are then compared to those obtained with the enhanced video data.

Spatial capture–recapture with partial identity: An application to camera traps

USGS Publications Warehouse

Augustine, Ben C.; Royle, J. Andrew; Kelly, Marcella J.; Satter, Christopher B.; Alonso, Robert S.; Boydston, Erin E.; Crooks, Kevin R.

2018-01-01

Camera trapping surveys frequently capture individuals whose identity is only known from a single flank. The most widely used methods for incorporating these partial identity individuals into density analyses discard some of the partial identity capture histories, reducing precision, and, while not previously recognized, introducing bias. Here, we present the spatial partial identity model (SPIM), which uses the spatial location where partial identity samples are captured to probabilistically resolve their complete identities, allowing all partial identity samples to be used in the analysis. We show that the SPIM outperforms other analytical alternatives. We then apply the SPIM to an ocelot data set collected on a trapping array with double-camera stations and a bobcat data set collected on a trapping array with single-camera stations. The SPIM improves inference in both cases and, in the ocelot example, individual sex is determined from photographs used to further resolve partial identities—one of which is resolved to near certainty. The SPIM opens the door for the investigation of trapping designs that deviate from the standard two camera design, the combination of other data types between which identities cannot be deterministically linked, and can be extended to the problem of partial genotypes.

Design of a Day/Night Star Camera System

NASA Technical Reports Server (NTRS)

Alexander, Cheryl; Swift, Wesley; Ghosh, Kajal; Ramsey, Brian

1999-01-01

This paper describes the design of a camera system capable of acquiring stars during both the day and night cycles of a high altitude balloon flight (35-42 km). The camera system will be filtered to operate in the R band (590-810 nm). Simulations have been run using MODTRAN atmospheric code to determine the worse case sky brightness at 35 km. With a daytime sky brightness of 2(exp -05) W/sq cm/str/um in the R band, the sensitivity of the camera system will allow acquisition of at least 1-2 stars/sq degree at star magnitude limits of 8.25-9.00. The system will have an F2.8, 64.3 mm diameter lens and a 1340X1037 CCD array digitized to 12 bits. The CCD array is comprised of 6.8 X 6.8 micron pixels with a well depth of 45,000 electrons and a quantum efficiency of 0.525 at 700 nm. The camera's field of view will be 6.33 sq degree and provide attitude knowledge to 8 arcsec or better. A test flight of the system is scheduled for fall 1999.

The upgrade of the H.E.S.S. cameras

NASA Astrophysics Data System (ADS)

Giavitto, Gianluca; Ashton, Terry; Balzer, Arnim; Berge, David; Brun, Francois; Chaminade, Thomas; Delagnes, Eric; Fontaine, Gerard; Füßling, Matthias; Giebels, Berrie; Glicenstein, Jean-Francois; Gräber, Tobias; Hinton, Jim; Jahnke, Albert; Klepser, Stefan; Kossatz, Marko; Kretzschmann, Axel; Lefranc, Valentin; Leich, Holger; Lüdecke, Hartmut; Lypova, Iryna; Manigot, Pascal; Marandon, Vincent; Moulin, Emmanuel; de Naurois, Mathieu; Nayman, Patrick; Ohm, Stefan; Penno, Marek; Ross, Duncan; Salek, David; Schade, Markus; Schwab, Thomas; Simoni, Rachel; Stegmann, Christian; Steppa, Constantin; Thornhill, Julian; Toussnel, Francois

2017-01-01

The High Energy Stereoscopic System (H.E.S.S.) is an array of five imaging atmospheric Cherenkov telescopes (IACT) located in Namibia. In order to assure the continuous operation of H.E.S.S. at its full sensitivity until and possibly beyond the advent of CTA, the older cameras, installed in 2003, are currently undergoing an extensive upgrade. Its goals are reducing the system failure rate, reducing the dead time and improving the overall performance of the array. All camera components have been upgraded, except the mechanical structure and the photo-multiplier tubes (PMTs). Novel technical solutions have been introduced: the upgraded readout electronics is based on the NECTAr analog memory chip; the control of the hardware is carried out by an FPGA coupled to an embedded ARM computer; the control software was re-written from scratch and it is based on modern C++ open source libraries. These hardware and software solutions offer very good performance, robustness and flexibility. The first camera was fielded in July 2015 and has been successfully commissioned; the rest is scheduled to be upgraded in September 2016. The present contribution describes the design, the testing and the performance of the new H.E.S.S. camera and its components.

In vitro near-infrared imaging of occlusal dental caries using a germanium-enhanced CMOS camera

NASA Astrophysics Data System (ADS)

Lee, Chulsung; Darling, Cynthia L.; Fried, Daniel

2010-02-01

The high transparency of dental enamel in the near-infrared (NIR) at 1310-nm can be exploited for imaging dental caries without the use of ionizing radiation. The objective of this study was to determine whether the lesion contrast derived from NIR transillumination can be used to estimate lesion severity. Another aim was to compare the performance of a new Ge enhanced complementary metal-oxide-semiconductor (CMOS) based NIR imaging camera with the InGaAs focal plane array (FPA). Extracted human teeth (n=52) with natural occlusal caries were imaged with both cameras at 1310-nm and the image contrast between sound and carious regions was calculated. After NIR imaging, teeth were sectioned and examined using more established methods, namely polarized light microscopy (PLM) and transverse microradiography (TMR) to calculate lesion severity. Lesions were then classified into 4 categories according to the lesion severity. Lesion contrast increased significantly with lesion severity for both cameras (p<0.05). The Ge enhanced CMOS camera equipped with the larger array and smaller pixels yielded higher contrast values compared with the smaller InGaAs FPA (p<0.01). Results demonstrate that NIR lesion contrast can be used to estimate lesion severity.

In vitro near-infrared imaging of occlusal dental caries using germanium enhanced CMOS camera.

PubMed

Lee, Chulsung; Darling, Cynthia L; Fried, Daniel

2010-03-01

The high transparency of dental enamel in the near-infrared (NIR) at 1310-nm can be exploited for imaging dental caries without the use of ionizing radiation. The objective of this study was to determine whether the lesion contrast derived from NIR transillumination can be used to estimate lesion severity. Another aim was to compare the performance of a new Ge enhanced complementary metal-oxide-semiconductor (CMOS) based NIR imaging camera with the InGaAs focal plane array (FPA). Extracted human teeth (n=52) with natural occlusal caries were imaged with both cameras at 1310-nm and the image contrast between sound and carious regions was calculated. After NIR imaging, teeth were sectioned and examined using more established methods, namely polarized light microscopy (PLM) and transverse microradiography (TMR) to calculate lesion severity. Lesions were then classified into 4 categories according to the lesion severity. Lesion contrast increased significantly with lesion severity for both cameras (p<0.05). The Ge enhanced CMOS camera equipped with the larger array and smaller pixels yielded higher contrast values compared with the smaller InGaAs FPA (p<0.01). Results demonstrate that NIR lesion contrast can be used to estimate lesion severity.

A drone detection with aircraft classification based on a camera array

NASA Astrophysics Data System (ADS)

Liu, Hao; Qu, Fangchao; Liu, Yingjian; Zhao, Wei; Chen, Yitong

2018-03-01

In recent years, because of the rapid popularity of drones, many people have begun to operate drones, bringing a range of security issues to sensitive areas such as airports and military locus. It is one of the important ways to solve these problems by realizing fine-grained classification and providing the fast and accurate detection of different models of drone. The main challenges of fine-grained classification are that: (1) there are various types of drones, and the models are more complex and diverse. (2) the recognition test is fast and accurate, in addition, the existing methods are not efficient. In this paper, we propose a fine-grained drone detection system based on the high resolution camera array. The system can quickly and accurately recognize the detection of fine grained drone based on hd camera.

Imaging spectroscopy using embedded diffractive optical arrays

NASA Astrophysics Data System (ADS)

Hinnrichs, Michele; Hinnrichs, Bradford

2017-09-01

Pacific Advanced Technology (PAT) has developed an infrared hyperspectral camera based on diffractive optic arrays. This approach to hyperspectral imaging has been demonstrated in all three infrared bands SWIR, MWIR and LWIR. The hyperspectral optical system has been integrated into the cold-shield of the sensor enabling the small size and weight of this infrared hyperspectral sensor. This new and innovative approach to an infrared hyperspectral imaging spectrometer uses micro-optics that are made up of an area array of diffractive optical elements where each element is tuned to image a different spectral region on a common focal plane array. The lenslet array is embedded in the cold-shield of the sensor and actuated with a miniature piezo-electric motor. This approach enables rapid infrared spectral imaging with multiple spectral images collected and processed simultaneously each frame of the camera. This paper will present our optical mechanical design approach which results in an infrared hyper-spectral imaging system that is small enough for a payload on a small satellite, mini-UAV, commercial quadcopter or man portable. Also, an application of how this spectral imaging technology can easily be used to quantify the mass and volume flow rates of hydrocarbon gases. The diffractive optical elements used in the lenslet array are blazed gratings where each lenslet is tuned for a different spectral bandpass. The lenslets are configured in an area array placed a few millimeters above the focal plane and embedded in the cold-shield to reduce the background signal normally associated with the optics. The detector array is divided into sub-images covered by each lenslet. We have developed various systems using a different number of lenslets in the area array. Depending on the size of the focal plane and the diameter of the lenslet array will determine the number of simultaneous different spectral images collected each frame of the camera. A 2 x 2 lenslet array will image four different spectral images of the scene each frame and when coupled with a 512 x 512 focal plane array will give spatial resolution of 256 x 256 pixel each spectral image. Another system that we developed uses a 4 x 4 lenslet array on a 1024 x 1024 pixel element focal plane array which gives 16 spectral images of 256 x 256 pixel resolution each frame. This system spans the SWIR and MWIR bands with a single optical array and focal plane array.

Views of the starboard P6 Truss solar array during STS-97

NASA Image and Video Library

2000-12-05

STS097-702-070 (3 December 2000) --- An astronaut inside Endeavour's crew cabin used a handheld 70mm camera to expose this frame of the International Space Station's starboard solar array wing panel, backdropped against an Earth horizon scene.

Manifold-Based Image Understanding

DTIC Science & Technology

2010-06-30

3] employs a Texas Instruments digital micromirror device (DMD), which consists of an array of N electrostatically actuated micromirrors . The camera...image x) is reflected off a digital micromirror device (DMD) array whose mirror orientations are modulated in the pseudorandom pattern φm supplied by a

LED characterization for development of on-board calibration unit of CCD-based advanced wide-field sensor camera of Resourcesat-2A

NASA Astrophysics Data System (ADS)

Chatterjee, Abhijit; Verma, Anurag

2016-05-01

The Advanced Wide Field Sensor (AWiFS) camera caters to high temporal resolution requirement of Resourcesat-2A mission with repeativity of 5 days. The AWiFS camera consists of four spectral bands, three in the visible and near IR and one in the short wave infrared. The imaging concept in VNIR bands is based on push broom scanning that uses linear array silicon charge coupled device (CCD) based Focal Plane Array (FPA). On-Board Calibration unit for these CCD based FPAs is used to monitor any degradation in FPA during entire mission life. Four LEDs are operated in constant current mode and 16 different light intensity levels are generated by electronically changing exposure of CCD throughout the calibration cycle. This paper describes experimental setup and characterization results of various flight model visible LEDs (λP=650nm) for development of On-Board Calibration unit of Advanced Wide Field Sensor (AWiFS) camera of RESOURCESAT-2A. Various LED configurations have been studied to meet dynamic range coverage of 6000 pixels silicon CCD based focal plane array from 20% to 60% of saturation during night pass of the satellite to identify degradation of detector elements. The paper also explains comparison of simulation and experimental results of CCD output profile at different LED combinations in constant current mode.

An array of virtual Frisch-grid CdZnTe detectors and a front-end application-specific integrated circuit for large-area position-sensitive gamma-ray cameras.

PubMed

Bolotnikov, A E; Ackley, K; Camarda, G S; Cherches, C; Cui, Y; De Geronimo, G; Fried, J; Hodges, D; Hossain, A; Lee, W; Mahler, G; Maritato, M; Petryk, M; Roy, U; Salwen, C; Vernon, E; Yang, G; James, R B

2015-07-01

We developed a robust and low-cost array of virtual Frisch-grid CdZnTe detectors coupled to a front-end readout application-specific integrated circuit (ASIC) for spectroscopy and imaging of gamma rays. The array operates as a self-reliant detector module. It is comprised of 36 close-packed 6 × 6 × 15 mm(3) detectors grouped into 3 × 3 sub-arrays of 2 × 2 detectors with the common cathodes. The front-end analog ASIC accommodates up to 36 anode and 9 cathode inputs. Several detector modules can be integrated into a single- or multi-layer unit operating as a Compton or a coded-aperture camera. We present the results from testing two fully assembled modules and readout electronics. The further enhancement of the arrays' performance and reduction of their cost are possible by using position-sensitive virtual Frisch-grid detectors, which allow for accurate corrections of the response of material non-uniformities caused by crystal defects.

Helmet-mounted uncooled FPA camera for use in firefighting applications

NASA Astrophysics Data System (ADS)

Wu, Cheng; Feng, Shengrong; Li, Kai; Pan, Shunchen; Su, Junhong; Jin, Weiqi

2000-05-01

From the concept and need background of firefighters to the thermal imager, we discuss how the helmet-mounted camera applied in the bad environment of conflagration, especially at the high temperature, and how the better matching between the thermal imager with the helmet will be put into effect in weight, size, etc. Finally, give a practical helmet- mounted IR camera based on the uncooled focal plane array detector for in firefighting.

Depth estimation using a lightfield camera

NASA Astrophysics Data System (ADS)

Roper, Carissa

The latest innovation to camera design has come in the form of the lightfield, or plenoptic, camera that captures 4-D radiance data rather than just the 2-D scene image via microlens arrays. With the spatial and angular light ray data now recorded on the camera sensor, it is feasible to construct algorithms that can estimate depth of field in different portions of a given scene. There are limitations to the precision due to hardware structure and the sheer number of scene variations that can occur. In this thesis, the potential of digital image analysis and spatial filtering to extract depth information is tested on the commercially available plenoptic camera.

High-temperature-superconducting magnetic susceptibility bolometer

NASA Technical Reports Server (NTRS)

Brasunas, J.; Lakew, B.; Lee, C.

1992-01-01

An infrared detector called the magnetic susceptibility bolometer is introduced which is based on the tmperature dependence of the diamagnetic screening of a high-Tc superconductor film near Tc. Results are reported for the response of a prototype model to modulated blackbody radiation. Possible improvements are discussed as is the potential sensitivity of an improved device.

High-Tc superconducting microbolometer for terahertz applications

NASA Astrophysics Data System (ADS)

Ulysse, C.; Gaugue, A.; Adam, A.; Kreisler, A. J.; Villégier, J.-C.; Thomassin, J.-L.

2002-05-01

Superconducting hot electron bolometer mixers are now a competitive alternative to Schottky diode mixers in the terahertz frequency range because of their ultra wideband (from millimeter waves to visible light), high conversion gain, and low intrinsic noise level. High Tc superconductor materials can be used to make hot electron bolometers and present some advantage in term of operating temperature and cooling. In this paper, we present first a model for the study of superconducting hot electron bolometers responsivity in direct detection mode, in order to establish a firm basis for the design of future THz mixers. Secondly, an original process to realize YBaCuO hot electron bolometer mixers will be described. Submicron YBaCuO superconducting structures are expitaxially sputter deposited on MgO substrates and patterned by using electron beam lithography in combination with optical lithography. Metal masks achieved by electron beam lithography are insuring a good bridge definition and protection during ion etching. Finally, detection experiments are being performed with a laser at 850 nm wavelength, in homodyne mode in order to prove the feasibility and potential performances of these devices.

Progress on Background-Limited Membrane-Isolated TES Bolometers for Far-IR/Submillimeter Spectroscopy

NASA Technical Reports Server (NTRS)

Kenyon, M.; Day, P. K.; Bradford, C. M.; Bock, J. J.; Leduc, H. G.

2006-01-01

To determine the lowest attainable phonon noise equivalent power (NEP) for membrane-isolation bolometers, we fabricated and measured the thermal conductance of suspended Si3N4 beams with different geometries via a noise thermometry technique. We measured beam cross-sectional areas ranging from 0.35 x 0.5 (micro)m(sup 2) to 135 x 1.0 (micro)m(sup 2) and beam lengths ranging from (micro)m to 8300 (micro)m. The measurements directly imply that membrane-isolation bolometers are capable of reaching a phonon noise equivalent power (NEP) of 4 x 10(sup -20)W/Hz(sup 1)/O . This NEP adequate for the Background-Limited Infrared-Submillimeter Spectrograph (BLISS) proposed for the Japanese SPICA observatory, and adequate for NASA's SAFIR observatory, a 10-meter, 4 K telescope to be deployed at L2. Further, we measured the heat capacity of a suspended Si3N4 membrane and show how this result implies that one can make membrane-isolation bolometers with a response time which is fast enough for BLISS.

Antenna-coupled transition-edge hot-electron microbolometers

NASA Astrophysics Data System (ADS)

Ali, Shafinaz; Timbie, Peter T.; Malu, Siddharth; McCammon, Dan; Nelms, Kari L.; Pathak, Rashmi; van der Weide, Daniel W.; Allen, Christine A.; Abrahams, J.; Chervenak, James A.; Hsieh, Wen-Ting; Miller, Timothy M.; Moseley, S. H., Jr.; Stevenson, Thomas R.; Wollack, Edward J.

2004-10-01

We are developing a new type of detector for observational cosmology and astrophysical research. Incoming radiation from the sky is coupled to a superconducting microstrip transmission line that terminates in a thin film absorber. At sub-Kelvin temperature, the thermal isolation between the electrons and the lattice makes it possible for the electrons in the small absorber (100's of cubic micro-meter) and superconducting bilayer (Transition Edge Sensor) to heat up by the radiation absorbed by the electrons of the normal absorbing layer. We call this detector a Transition-edge Hot-electron Micro-bolometer (THM). THMs can be fabricated by photo lithography, so it is relatively easy to make matched detectors for a large focal plane array telescope. We report on the thermal properties of Mo/Au THMs with Bi/Au absorbers.

Bolometric detector systems for IR and mm-wave space astronomy

NASA Technical Reports Server (NTRS)

Church, S. E.; Lange, A. E.; Mauskopf, P. D.; Hristov, V.; Bock, J. J.; DelCastillo, H. M.; Beeman, J.; Ade, P. A. R.; Griffin, M. J.

1996-01-01

Recent developments in bolometric detector systems for millimeter and submillimeter wave space astronomy are described. Current technologies meet all the requirements for the high frequency instrument onboard the cosmic background radiation anisotropy satellite/satellite for the measurement of background anisotropies (COBRAS/SAMBA) platform. It is considered that the technologies that are currently being developed will significantly reduce the effective time constant and/or the cooling requirements of bolometric detectors. These technologies lend themselves to the fabrication of the large format arrays required for the Far Infrared and Submillimeter Space Telescope (FIRST). The scientific goals and detector requirements of the COBRAS/SAMBA platform that will use infrared bolometers are reviewed and the baseline detector system is described, including the feed optics, the infrared filters, the cold amplifiers and the warm readout electronics.

THERMAP : a mid-infrared spectro-imager for the Marco Polo R mission

NASA Astrophysics Data System (ADS)

Groussin, O.; Brageot, E.; Reynaud, J.-L.; Lamy, P.; Jorda, L.; Licandro, J.; Helbert, J.; Knollenberg, J.; Kührt, E.; Delbó, M.

2012-09-01

We present THERMAP, a mid-infrared (8-16 μm) spectro-imager based on uncooled micro-bolometer detector arrays. Due to the recent technological development of these detectors, which have undergone significant improvements in the last decade, we wanted to test their performances for a space mission to small bodies in the inner Solar System. THERMAP was selected by ESA in January 2012 for a one year assessment study, in the framework of a call for declaration of interest in science instrumentation for the Marco Polo R Cosmic Vision mission. In this paper, we present some results of this study and in particular demonstrate that the new generation of uncooled micro-bolometer detectors has all the imaging and spectroscopic capabilities to fulfill the scientific objectives of the Marco Polo R mission. THERMAP scientific objectives - The midinfrared instrument of the Marco Polo R mission must be able i) to determine the surface temperature by mapping the entire surface with an absolute accuracy of at least 5 K (goal 1 K) above 200 K, ii) to determine the thermal inertia with an accuracy of 10% and iii) to determine the surface composition by mapping the entire surface with a spectral resolution of 70 between 8 and 16 μm. The above mappings should be performed with a spatial resolution of 10 m for the entire surface (global characterization) and 10 cm for the sampling sites (local characterization). THERMAP imaging capabilities - In order to test the imaging capabilities of the THERMAP uncooled microbolometer detector, we set up an experiment based on a 640x480 ULIS micro-bolometer array, a germanium objective and a black body. Using the results of this experiment, we show that calibrated radiometric images can be obtained down to at least 258 K (lower limit of our experiment), and that two calibration points are sufficient to determine the absolute scene temperature with an accuracy better than 1.5 K. An extrapolation to lower temperatures provides an accuracy of about 5 K at 180 K, the lowest temperature the detector can measure. THERMAP spectroscopic capabilites - In order to test the spectroscopic performances of the detector, we added flux attenuating neutral density mid-infrared filters (transmittance: 50%, 10%, 1%) to our experiment. Our results show that we can perform spectroscopic measurements with a spectral resolution R=40-80 in the wavelength range 8-16 μm for a scene temperature larger than 300 K, the typical surface temperature of a Near Earth Asteroid at 1 AU from the Sun. THERMAP preliminary design - From the above results, we defined a preliminary design for the instrument. THERMAP is a mid-infrared (8-16 μm) spectro-imager based on two uncooled microbolometer arrays. It is composed of two channels, one for imaging and one for spectroscopy. A flip mirror allows switching between the two channels. Calibration is performed using deep space and two black bodies at known temperature. The design of the THERMAP instrument has a strong heritage from the MERTIS instrument on board Bepi-Colombo [1], which guarantees its feasibility and reliability. Our design is very flexible in term of operations, which is fundamental for a mission to a binary asteroid system (1996 FG3). The THERMAP instrument will be proposed for Marco Polo R and any future space missions to small bodies in the inner solar system.

Auto-converging stereo cameras for 3D robotic tele-operation

NASA Astrophysics Data System (ADS)

Edmondson, Richard; Aycock, Todd; Chenault, David

2012-06-01

Polaris Sensor Technologies has developed a Stereovision Upgrade Kit for TALON robot to provide enhanced depth perception to the operator. This kit previously required the TALON Operator Control Unit to be equipped with the optional touchscreen interface to allow for operator control of the camera convergence angle adjustment. This adjustment allowed for optimal camera convergence independent of the distance from the camera to the object being viewed. Polaris has recently improved the performance of the stereo camera by implementing an Automatic Convergence algorithm in a field programmable gate array in the camera assembly. This algorithm uses scene content to automatically adjust the camera convergence angle, freeing the operator to focus on the task rather than adjustment of the vision system. The autoconvergence capability has been demonstrated on both visible zoom cameras and longwave infrared microbolometer stereo pairs.

Upcoming planetary missions and the applicability of high temperature superconductor bolometers

NASA Technical Reports Server (NTRS)

Brasunas, J.; Kunde, V.; Moseley, H.; Lakew, B.

1991-01-01

Planetary missions to Mars and beyond can last 11 years and longer, making impractical the use of stored cryogens. Passive radiative coolers and single-stage mechanical coolers remain possibilities. Cassini and Comet Rendezvous/Asteroid Fly-by (CRAF), both using the newly developed Mariner Mark 2 spacecraft, will be the next outer planet missions after Galileo; they are intended to provide information on the origin and evolution of the solar system. CRAF is slated for a 1994 launch. Cassini was chosen by ESA and will be launched by a Titan 4/Centaur in 1996. It will fly by Jupiter in 2000, inject an ESA-supplied probe into Titan in 2002, and take data in Saturn's orbit from 2002 to 2006. NASA/Goddard is currently developing a prototype Fourier transform spectrometer, the Composite Infrared Spectrometer (CIRS), for the Cassini mission. The baseline infrared detectors for CIRS are HgCdTe to 16 microns and Schwarz-type thermopiles from 16 to 1000 microns. The far infrared focal plane could be switched from thermopiles to high temperature superconductor (HTS) bolometers between now and 1996. An HTS bolometer could be built using the kinetic inductance effect, or the sharp resistance change at the transition. The transition-edge bolometer is more straightforward to implement, and initial efforts at NASA/Goddard are directed to that device. A working device was made and tested in early 1989. It also has somewhat elevated noise levels below 100 Hz. Upcoming efforts will center on reducing the time constant of the HTS bolometer by attempting to deposit an HTS film on a diamond substrate, and by thinning SrTiO3 substrates. Attempts will be made to improve the film quality to reduce the 1/4 noise level, and to improve the thermal isolation to increase the bolometer sensitivity. An attempt is being made to deposit good-quality HTS films on diamond films using a metal-organic chemical vapor deposition (MOCVD) technique.