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Articles 31 - 37 of 37

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The Advanced Compton Telescope, S E. Boggs, J Kurfess, James M. Ryan, Elena Aprile, Neil Gehrels, R M. Kippen, Marc Leising, U Oberlack, Cornelia B. Wunderer, Allen Zych, Peter F. Bloser, M Harris, A Hoover, Alexei Klimenk, Dan Kocevski, Mark L. Mcconnell, Peter Milne, E I. Novikova, B F. Phlips, Mark Polsen, Steven Sturner, Derek Tournear, G Weidenspointer, Eric Wulf, A Zoglauer, Matthew Baring, John Beacom, Lars Bildsten, Charles Dermer, Dieter H. Hartman, Margarita Hernanz, David Smith, Sumner Starrfield Jun 2006

The Advanced Compton Telescope, S E. Boggs, J Kurfess, James M. Ryan, Elena Aprile, Neil Gehrels, R M. Kippen, Marc Leising, U Oberlack, Cornelia B. Wunderer, Allen Zych, Peter F. Bloser, M Harris, A Hoover, Alexei Klimenk, Dan Kocevski, Mark L. Mcconnell, Peter Milne, E I. Novikova, B F. Phlips, Mark Polsen, Steven Sturner, Derek Tournear, G Weidenspointer, Eric Wulf, A Zoglauer, Matthew Baring, John Beacom, Lars Bildsten, Charles Dermer, Dieter H. Hartman, Margarita Hernanz, David Smith, Sumner Starrfield

Space Science Center

The Advanced Compton Telescope (ACT), the next major step in gamma-ray astronomy, will probe the fires where chemical elements are formed by enabling high-resolution spectroscopy of nuclear emission from supernova explosions. During the past two years, our collaboration has been undertaking a NASA mission concept study for ACT. This study was designed to (1) transform the key scientific objectives into specific instrument requirements, (2) to identify the most promising technologies to meet those requirements, and (3) to design a viable mission concept for this instrument. We present the results of this study, including scientific goals and expected performance, mission design, …


Position Resolution In Labr3 And Lacl3 Scintillators Using Position-Sensitive Photomultiplier Tubes, Peter F. Bloser, Mark L. Mcconnell, John R. Macri, James M. Ryan, Justin Baker Jan 2006

Position Resolution In Labr3 And Lacl3 Scintillators Using Position-Sensitive Photomultiplier Tubes, Peter F. Bloser, Mark L. Mcconnell, John R. Macri, James M. Ryan, Justin Baker

Space Science Center

Advanced scintillator materials such as LaBr3:Ce and LaCl3:Ce hold great promise for future hard X-ray and gamma-ray astrophysics missions due to their high density, high light output, good linearity, and fast decay times. Of particular importance for future space-based imaging instruments, such as coded-aperture telescopes, is the precise spatial location of individual gamma-ray interactions. We have investigated the position and energy resolution achievable within monolithic (5 cm × 5 cm × 1 cm) LaBr3:Ce and LaCl3:Ce crystals using position-sensitive light readout devices, including a position-sensitive photomultiplier tube and a multi-anode photomultiplier tube. We present the results of these tests and …


Radiation Damage And Activation From Proton Irradiation Of Advanced Scintillators, Peter F. Bloser, Mark L. Mcconnell, John R. Macri, P J. Bruillard, James M. Ryan, W Hajdas Jan 2006

Radiation Damage And Activation From Proton Irradiation Of Advanced Scintillators, Peter F. Bloser, Mark L. Mcconnell, John R. Macri, P J. Bruillard, James M. Ryan, W Hajdas

Space Science Center

We present results from a proton accelerator beam test to measure radiation damage and activation in advanced scintillator materials. Samples of LaBr3:Ce and LaCl3:Ce were exposed to protons from 40-250 MeV at the Proton Irradiation Facility of the Paul Scherrer Institute in Switzerland. Twelve energy bands were used to simulate the spectrum of the South Atlantic Anomaly (SAA), with different samples exposed to the equivalent of 4 months, 1 year, and 5 years of SAA passage. No significant decrease in light output was found due to radiation damage, indicating that these new scintillator materials are radiation tolerant. High-resolution spectra of …


Simulated Performance Of 3-Dti Gamma-Ray Telescope Concepts, Peter F. Bloser, Mark L. Mcconnell, James M. Ryan, Louis M. Barbier, Alan Centa, Stanley D. Hunter, John F. Krizmanic, Jason T. Link, Geoergia A. De Nolfo, Seunghee Son Jan 2006

Simulated Performance Of 3-Dti Gamma-Ray Telescope Concepts, Peter F. Bloser, Mark L. Mcconnell, James M. Ryan, Louis M. Barbier, Alan Centa, Stanley D. Hunter, John F. Krizmanic, Jason T. Link, Geoergia A. De Nolfo, Seunghee Son

Space Science Center

We present Monte Carlo simulations of two astronomical gamma-ray telescope concepts based on the ThreeDimensional Track Imager (3- DTI) detector. The 3-DTI consists of a time projection chamber with two-dimensional, crossedstrip micro-well detector readout. The full three- dimensional reconstruction of charged-particle tracks in the gas volume is obtained from transient digitizers, which record the time signature of the charge collected in the wells of each strip. Such detectors hold great promise for advanced Compton telescope (ACT) and advanced pair telescope (APT) concepts due to the very precise measurement of charged particle momenta that is possible (Compton recoil electrons and electron-positron …


Environmental Audit Of The Rose Hill Campus, Nicole Marshall, Maria Nissi, Brian Flaherty, Carl Van Ostrand, Ian Mcclelland Jan 2002

Environmental Audit Of The Rose Hill Campus, Nicole Marshall, Maria Nissi, Brian Flaherty, Carl Van Ostrand, Ian Mcclelland

Student Theses 2001-2013

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Coded-Aperture X-Ray/Gamma-Ray Telescope For Arc-Minute Localization Of Gamma-Ray Bursts, M L. Cherry, P P. Altice, D L. Band, J Buckley, T G. Guzik, P L. Hink, S C. Kappadath, John R. Macri, J L. Matteson, Mark L. Mcconnell, Terence J. O'Neill, James M. Ryan, K R. Slavis, J G. Stacy, Allen Zych Oct 1999

Coded-Aperture X-Ray/Gamma-Ray Telescope For Arc-Minute Localization Of Gamma-Ray Bursts, M L. Cherry, P P. Altice, D L. Band, J Buckley, T G. Guzik, P L. Hink, S C. Kappadath, John R. Macri, J L. Matteson, Mark L. Mcconnell, Terence J. O'Neill, James M. Ryan, K R. Slavis, J G. Stacy, Allen Zych

Space Science Center

MARGIE will be a large-area, wide field-of-view, hard x- ray/gamma-ray imaging telescope capable of providing accurate positions for faint gamma-ray bursts in near-real- time and of performing a sensitive survey of both steady and transient cosmic sources. The instrument is designed to image faint bursts at the low-intensity end of the log N - log S distribution. MARGIE was recently selected by NASA for a mission-concept study for an Ultra Long Duration Balloon flight. We describe a program to develop an instrument based on the new detector technology of either cadmium zinc telluride room-temperature semiconductors or pixelated cesium iodide scintillators …


Nanosecond Optical Transmission Studies Of Laser Annealing In Ion-Implanted Silicon-On-Sapphire, M. C. Lee, H. W. Lo, A. Aydinli, G. J. Trott, A. Compaan, Edward Boyd Hale Jan 1983

Nanosecond Optical Transmission Studies Of Laser Annealing In Ion-Implanted Silicon-On-Sapphire, M. C. Lee, H. W. Lo, A. Aydinli, G. J. Trott, A. Compaan, Edward Boyd Hale

Physics Faculty Research & Creative Works

Time-resolved optical transmission has been studied using 633 and 514 nm CW probes on ion-implantation-amorphized silicon-on-sapphire during annealing by a 10 nsec, ⊥ J/cm2 pulse at either 532 nm or 485 nm. As recrystallization sets in the transmitted signal at 514 nm rises by ⊥ 103 in ⊥ 60 nsec and provides a measure of regrowth velocity. Beyond 200 nsec the much slower transmission rise is used to provide an estimate of the Si cooling rate. The difference in transmission observed between initially crystalline and initially amorphous Si provide an estimate of the latent heat of recrystallization of the amorphous …