864 research outputs found
Continued Studies of Single-Sided Charge-Sharing CZT Strip Detectors
In this paper, we report progress in the study of thick single-sided charge-sharing cadmium zinc telluride (CZT) strip detector modules designed to perform gammaray spectroscopy and 3-D imaging. We report on continuing laboratory and simulation measurements of prototype detectors with 11×11 unit cells (15×15×7.5mm3 ). We report preliminary measurements of the 3-D spatial resolution. Our studies are aimed at developing compact, efficient, detector modules for 0.05 to 1 MeV gamma measurements while minimizing the number and complexity of the electronic readout channels. This is particularly important in space-based coded aperture and Compton telescope instruments that require large area, large volume detector arrays. Such arrays will be required for the NASA’s Black Hole Finder Probe (BHFP) and Advanced Compton Telescope (ACT). This design requires an anode pattern with contacts whose dimensions and spacing are roughly the size of the ionization charge cloud. The first prototype devices have 125µm anode contacts on 225µm pitch. Our studies conclude that finer pitch contacts will be required to improve imaging efficiency
Further studies of single-sided charge-sharing CZT strip detectors
We report progress in the study of a thick CZT strip detector module designed to perform gamma-ray spectroscopy and 3-D imaging. We report preliminary performance measurements of 7.5 mm thick single-sided charge-sharing strip detector prototype devices. This design features both row and column contacts on the anode surface. This electron-only approach addresses problems associated with poor hole transport in CZT that limit the thickness and energy range of double-sided strip detectors. This work includes laboratory and simulation studies aimed at developing compact, efficient, detector modules for 0.05 to 1 MeV gamma measurements while minimizing the number and complexity of the electronic readout channels. This is particularly important in space-based coded aperture and Compton telescope instruments that require large area, large volume detector arrays. Such arrays will be required for the NASA Black Hole Finder Probe (BHFP)and Advanced Compton Telescope (ACT). This new design requires an anode pattern with contacts whose dimensions and spacing are roughly the size of the ionization charge cloud. The first prototype devices have 125 ÎĽm anode contacts on 225 ÎĽm pitch. Our results demonstrate the principle of operation but suggest that even finer anode contact feature sizes will be necessary to achieve the desired performance
Karolina Gnatowski: Some Kind of Duty
Exhibit catalog for Karolina Gnatowski: Some Kind of Duty, January 17-March 31, 2019https://via.library.depaul.edu/museum-publications/1018/thumbnail.jp
Unheimlich leiden:Über die Empfindsamkeit der Körper, die Übertragbarkeit von Angst und was gemeinhin dagegen unternommen wird – am Beispiel Autismus
Um das Unheimliche eines Leidens zu beschreiben und die Signalfunktion des Unheimlichen an Zusammenhängen zwischen Affekt, Körper und Gesellschaft zu untersuchen, werde ich mich im Folgenden einem konkreten – nach den internationalen Diagnoseschemata ICD und DSM einheitlich klassifizierbaren – Krankheitsbild widmen: dem Autismus-Spektrum
Was nicht täuscht
Angst bei Kierkegaard, Heidegger und Lacan. Kierkegaard und Lacan gut - Heidegger reaktionär. Funktion und Praxis der Angst in der Psychoanalyse. Die Angst ist das, was nicht täuscht. Objektbeziehung und Subjektkonstitution. Objekt a als Objektursache des Begehrens. Es gibt keine andere Auferstehung als die des Körpers. Der Andere weiß das. Gleichheit der Intelligenzen bei Ranciere. Subjektivierung qua Unterwerfung als Gegenstand der pädagogischen Verhältnisse. Verdummung als Methode. Verhaltenstherapie und Lerntheorie. Als ob ein Kind mit Autismus denken könnte
Single-sided CZT strip detectors
We report progress in the study of thick CZT strip detectors for 3-d imaging and spectroscopy and discuss two approaches to device design. We present the spectroscopic, imaging, detection efficiency and response uniformity performance of prototype devices. Unlike double-sided strip detectors, these devices feature both row and column contacts implemented on the anode surface. This electron-only approach circumvents problems associated with poor hole transport in CZT that normally limit the thickness and energy range of double-sided strip detectors. These devices can achieve similar performance to pixel detectors. The work includes laboratory and simulation studies aimed at developing compact, efficient, detector modules for 0.05 to 1 MeV gamma radiation measurements. The low channel count strip detector approach can significantly reduce the complexity and power requirements of the readout electronics. This is particularly important in space-based coded aperture or Compton telescope instruments requiring large area, large volume detector arrays. Such arrays will be required for NASA\u27s Black Hole Finder Probe (BHFP) and Advanced Compton Telescope (ACT)
A prototype ASIC for APD array readout of scintillating plastic fibers
We report on the development of custom front-end electronics for use with avalanche photodiode (APD) arrays as part of a NASA technology study for the readout of scintillating plastic fibers. APD arrays featuring 64 1 mm square pixels are used. We demonstrate that a pixel of these APD arrays coupled to relatively thin (0.25 mm) and short (15 cm) scintillating plastic fibers can be used to detect and measure the tracks of even minimum ionizing particles (MIPs). An applicationspecific integrated circuit (ASIC) implementation of the electronics is required to produce a detector sufficiently compact for practical use in a flight experiment featuring many thousands of channels. This paper briefly describes the detector concept and performance and presents the design and performance of a four-channel prototype ASIC fabricated using the 0.35 micron TSMC process
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