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: http://www.stsci.edu/stsci/meetings/space_detectors/abstractsI.htm
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CCDs for the Optical - Ultraviolet Spectral RegionMark Clampin Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (1) Introduction - the science capabilities of CCDs: 200 nm - 1000 nm imaging, but also <200 nm - future missions requiring CCDs (2) Current state of the art in device performance - read noise, dark noise, array formats, architectures; quantum efficiency: FUV, NUV, optical-NIR, quantum yield in FUV/NUV; backside processing & deep depletion; performance summary and tradeoffs(3) Technical challenges for space applications - radiation damage; radiation environments; charge transfer efficiency, hot pixels; mitigation: mini-channel, p type CCDs, SiC, small format reads; flight packaging; procurement: transition of commercial market to CMOS; science CCD vendors (follow-up to FOSI report) (4) New Technologies - Deep-depletion devices; SiC; Hybrid CCD devices ; Pin-Array
HEB HETERODYNE SENSORS FOR SUBMILLIMETER/FAR-IR ASTRONOMY:STATE-OF-THE-ART AND FUTURE DIRECTIONSWilliam R. McGrath* Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109
Spectroscopic observations at sub-millimeter/far-IR wavelengths are critical to the understanding of star formation, and the chemistry, energy balance, and dynamics of the interstellar medium. These observations are also required for the study of "dusty" galaxies which emit mainly in this wavelength range; and for the study of highly red-shifted objects. These science objectives are clearly spelled out in NASA’s Strategic Plan and more specifically in the Code S Roadmap for the Structure and Evolution of the Universe. Heterodyne sensors based on ultra-fast hot-electron bolometer (HEB) mixers have recently emerged as the most promising detector for science observations at far-IR wavelengths corresponding to frequencies above about 1 THz. Unlike present superconductive SIS mixers, HEB mixers have no frequency limitation set by the energy gap of the superconductor. Thus operation from below 1 THz to over 10 THz is possible. In addition, the noise temperature and local oscillator power requirements are essentially independent of frequency. The unique properties of HEB mixers allow for the development of unique and powerful new observational instruments for radio astronomy missions. The current status and future directions for the development of HEB sensors will be discussed. *This presentation will contain contributions from my co-workers and collaborators: Boris Karasik, Anders Skalare, Rolf Wyss, Pierre Echternach, Bruce Bumble, Rick LeDuc, Dan Prober, Irfan Siddiq
Science Drivers for UV-Optical Space Astrophysics Detector Development Jon A. Morse, Center for Astrophysics and Space Astronomy, University of Colorado I review science goals for UV-optical space astrophysics missions and discuss required detector technology development during the next two decades. Small, medium, and large mission concepts are summarized, including the Space UltraViolet-Optical (SUVO) telescope and several Explorers. I will emphasize the need to develop detectors with large format, low noise, and high quantum efficiency in order to achieve large gains in discovery efficiency over current capabilities. The development of energy-resolving detector arrays for UV-optical-NIR imaging and spectroscopy may revolutionize our study of planets, stars, galaxies, and the Universe.
Caroline K. Stahle, GSFC An x-ray calorimeter consists of an absorber to thermalize incident x-ray photons, a weak link to a low-temperature heat sink to provide the thermal isolation required for a temperature change to be sensed, and a sensitive thermometer to measure that temperature change. This basic framework can be realized in a variety of implementations. Several of these have demonstrated spectral resolution better than 10 eV FWHM at 6 keV, and progress towards the 2 eV resolution needed for the Constellation-X and XEUS observatories continues to be made. The fundamental limit on the energy resolution of a microcalorimeter is determined by the effective bandwidth of the measurement of a temperature increase in the presence of thermal fluctuations. I will discuss the calculation of this fundamental limit, non-ideal effects that are impediments to achieving predicted resolutions, and optimization issues for several of the more successful x-ray calorimeter implementations. I will conclude with an overview of the present state-of-the-art and a discussion of future directions.
Far-infrared Photon-Counting Detectors Rob Schoelkopf , Yale University, Dept. of Applied Physics and Physics I will attempt to review the state of the art and future prospects for very high sensitivity direct detectors in the wavelength range from a few millimeters to 100 microns. Though excellent heterodyne detectors for this portion of the spectrum are available, and can approach the fundamental limit of 1/2 photon per mode of added noise, a high-performance direct detector can still be superior in low-background applications. The simplicity and scalability for producing arrays of direct detectors may also be favorable in comparison with heterodyne systems. There are several types of cryogenic detectors currently in development which have promise to produce sensitivity levels many orders of magnitude better than the present noise-equivalent powers of ~10^-17- 10^-18 Watts/rt(Hz). These new devices include antenna-coupled bolometers using NIS (normal-insulator-superconductor) junctions and transition-edge sensor (TES) bolometers, as well as cryogenic photoconductors based on superconductors (SQPC) or semiconductor quantum dots. The photoconducting detectors in particular may be capable of true single-photon counting in the submillimeter band, as recently demonstrated by Komiyama et al. I will focus on the prospects and challenges for these devices, and on recent progress at Yale & NASA/GSFC on detector readouts using single-electron transistors (SETs). http://www.eng.yale.edu/rslab - our group's home page http://www.eng.yale.edu/aphy - department page, with some links http://www.eng.yale.edu/aphy/grad.pdf - dept. grad. brochure, with links
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