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Articles 1 - 9 of 9
Full-Text Articles in Physical Sciences and Mathematics
Further Studies Of Single-Sided Charge-Sharing Czt Strip Detectors, B Donmez, John R. Macri, Mark L. Mcconnell, James M. Ryan, Mark Widholm, T Narita, L A. Hamel
Further Studies Of Single-Sided Charge-Sharing Czt Strip Detectors, B Donmez, John R. Macri, Mark L. Mcconnell, James M. Ryan, Mark Widholm, T Narita, L A. Hamel
Space Science Center
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 …
Imaging Solar Neutrons Below 10 Mev In The Inner Heliosphere, U Bravar
Imaging Solar Neutrons Below 10 Mev In The Inner Heliosphere, U Bravar
Space Science Center
Inner heliosphere measurements of the Sun can be conducted with the proposed Solar Sentinel spacecraft and mission. One of the key measurements that can be made inside the orbit of the Earth is that of lower energy neutrons that arise in flares from nuclear reactions. Solar flare neutrons below 10 MeV suffer heavy weak-decay losses before reaching 1 AU. For heliocentric radii as close as 0.3 AU, the number of surviving neutrons from a solar event is dramatically greater. Neutrons from 1-10 MeV provide a new measure of heavy ion interactions at low energies, where the vast majority of energetic …
Caster: A Concept For A Black Hole Finder Probe Based On The Use Of New Scintillator Technologies, Mark L. Mcconnell, Peter F. Bloser, G L. Case, M L. Cherry, J Cravens, T G. Guzik, K Hurley, R M. Kippen, John R. Macri, R S. Miller, W Paciesas, James M. Ryan, B Schaefer, J G. Stacy, W T. Vestrand, J P. Wefel
Caster: A Concept For A Black Hole Finder Probe Based On The Use Of New Scintillator Technologies, Mark L. Mcconnell, Peter F. Bloser, G L. Case, M L. Cherry, J Cravens, T G. Guzik, K Hurley, R M. Kippen, John R. Macri, R S. Miller, W Paciesas, James M. Ryan, B Schaefer, J G. Stacy, W T. Vestrand, J P. Wefel
Space Science Center
The primary scientific mission of the Black Hole Finder Probe (BHFP), part of the NASA Beyond Einstein program, is to survey the local Universe for black holes over a wide range of mass and accretion rate. One approach to such a survey is a hard X-ray coded-aperture imaging mission operating in the 10-600 keV energy band, a spectral range that is considered to be especially useful in the detection of black hole sources. The development of new inorganic scintillator materials provides improved performance (for example, with regards to energy resolution and timing) that is well suited to the BHFP science …
Gas Micro-Well Track Imaging Detectors For Gamma-Ray Astronomy, Peter F. Bloser, S Hunter, James M. Ryan, Mark L. Mcconnell, John R. Macri
Gas Micro-Well Track Imaging Detectors For Gamma-Ray Astronomy, Peter F. Bloser, S Hunter, James M. Ryan, Mark L. Mcconnell, John R. Macri
Space Science Center
We describe our program to develop gas micro-well detectors (MWDs) as three-dimensional charged particle trackers for use in advanced gamma-ray telescope concepts. A micro-well detector consists of an array of individual micro-patterned gas proportional counters opposite a planar drift electrode. The well anodes and cathodes may be connected in X and Y strips, respectively, to provide two-dimensional imaging. When combined with transient digitizer electronics, which record the time signature of the charge collected in the wells of each strip, full three-dimensional reconstruction of charged-particle tracks in large gas volumes is possible. Such detectors hold great promise for advanced Compton telescope …
Mega: A Medium-Energy Gamma-Ray Astronomy Mission Concept, Peter F. Bloser, James M. Ryan, Mark L. Mcconnell, John R. Macri, U Bravar, G Kanbach, R Andritsche, M Ajello, A Zoglauer, S Hunter, B F. Phlips, Eric Wulf, Dieter H. Hartman, R S. Miller, W Paciesas, Allen Zych, R M. Kippen, W T. Vestrand, M L. Cherry, T G. Guzik, J G. Stacy, J P. Wefel, V Reglero, G Dicocco, J Cravens
Mega: A Medium-Energy Gamma-Ray Astronomy Mission Concept, Peter F. Bloser, James M. Ryan, Mark L. Mcconnell, John R. Macri, U Bravar, G Kanbach, R Andritsche, M Ajello, A Zoglauer, S Hunter, B F. Phlips, Eric Wulf, Dieter H. Hartman, R S. Miller, W Paciesas, Allen Zych, R M. Kippen, W T. Vestrand, M L. Cherry, T G. Guzik, J G. Stacy, J P. Wefel, V Reglero, G Dicocco, J Cravens
Space Science Center
The Medium Energy Gamma-ray Astronomy (MEGA) telescope concept will soon be proposed as a MIDEX mission. This mission would enable a sensitive all-sky survey of the medium-energy gamma-ray sky (0.4 - 50 MeV) and bridge the huge sensitivity gap between the COMPTEL and OSSE experiments on the Compton Gamma Ray Observatory, the SPI and IBIS instruments on INTEGRAL, and the visionary Advanced Compton Telescope (ACT) mission. The scientific goals include, among other things, compiling a much larger catalog of sources in this energy range, performing far deeper searches for supernovae, better measuring the galactic continuum and line emissions, and identifying …
Atmospheric Neutron Measurements With The Sontrac Science Model, U Bravar, E O. Fluckiger, Kevin Godin, Zachary C. Hansen, John R. Macri, Mark L. Mcconnell, R S. Miller, M R. Moser, James M. Ryan
Atmospheric Neutron Measurements With The Sontrac Science Model, U Bravar, E O. Fluckiger, Kevin Godin, Zachary C. Hansen, John R. Macri, Mark L. Mcconnell, R S. Miller, M R. Moser, James M. Ryan
Space Science Center
–The SOlar Neutron TRACking (SONTRAC) telescope was originally developed to measure the energy spectrum and incident direction of neutrons produced in solar flares, in the energy range 20 - 250 MeV. While developed primarily for solar physics, the SONTRAC detector may be employed in virtually any application requiring both energy measurement and imaging capabilities. The SONTRAC Science Model (SM) is presently being operated at the University of New Hampshire (UNH) as a ground-based instrument to investigate the energy spectrum, zenith and azimuth angle dependence of the cosmic-ray induced sea-level atmospheric neutron flux. SONTRAC measurements are based on the non-relativistic double …
Continued Studies Of Single-Sided Charge-Sharing Czt Strip Detectors, B Donmez, John R. Macri, Mark L. Mcconnell, James M. Ryan, Mark Widholm, L A. Hamel, T Narita
Continued Studies Of Single-Sided Charge-Sharing Czt Strip Detectors, B Donmez, John R. Macri, Mark L. Mcconnell, James M. Ryan, Mark Widholm, L A. Hamel, T Narita
Space Science Center
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 …
Development Of The Fast Neutron Imaging Telescope, U Bravar, P J. Bruillard, E O. Fluckiger, John R. Macri, A L. Mackinnon, Mark L. Mcconnell, M R. Moser, James M. Ryan, R S. Woolf
Development Of The Fast Neutron Imaging Telescope, U Bravar, P J. Bruillard, E O. Fluckiger, John R. Macri, A L. Mackinnon, Mark L. Mcconnell, M R. Moser, James M. Ryan, R S. Woolf
Space Science Center
We report on the development of a next generation neutron telescope, with imaging and energy measurement capabilities, sensitive to neutrons in the 2-20 MeV energy range. The Fast Neutron Imaging Telescope (FNIT) was initially conceived to study solar neutrons as a candidate instrument for the Inner Heliosphere Sentinels (IHS) program under formulation at NASA. This detector is now being adapted to locate Special Nuclear Material (SNM) for homeland security purposes by detecting fission neutrons and reconstructing the image of their source. In either case, the detection principle is based on multiple elastic neutron-proton scatterings in organic scintillator. By reconstructing the …
A Hard X-Ray Polarimeter Designed For Transient Astrophysical Sources, Mark L. Mcconnell, Peter F. Bloser, Jason S. Legere, John R. Macri, T Narita
A Hard X-Ray Polarimeter Designed For Transient Astrophysical Sources, Mark L. Mcconnell, Peter F. Bloser, Jason S. Legere, John R. Macri, T Narita
Space Science Center
— This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are particularly interested in X-rays that are emitted from solar flares and gamma-ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead, to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high-Z crystal scintillator. We can monitor individual Compton …