The Compton Spectrometer and Imager Project for MeV Astronomy

John A. Tomsick; Steven E. Boggs; Andreas Zoglauer; Eric Wulf; Lee Mitchell; Bernard Phlips; Clio Sleator; Terri Brandt; Albert Shih; Jarred Roberts; Pierre Jean; Peter von Ballmoos; Juan Martinez Oliveros; Alan Smale; Carolyn Kierans; Dieter Hartmann; Mark Leising; Marco Ajello; Eric Burns; Chris Fryer; Pascal Saint-Hilaire; Julien Malzac; Fabrizio Tavecchio; Valentina Fioretti; Andrea Bulgarelli; Giancarlo Ghirlanda; Hsiang-Kuang Chang; Tadayuki Takahashi; Kazuhiro Nakazawa; Shigeki Matsumoto; Tom Melia; Thomas Siegert; Alexander Lowell; Hadar Lazar; Jacqueline Beechert; Hannah Gulick

arXiv · 2109.10403

The Compton Spectrometer and Imager Project for MeV Astronomy

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Abstract

The Compton Spectrometer and Imager (COSI) is a 0.2-5 MeV Compton telescope capable of imaging, spectroscopy, and polarimetry of astrophysical sources. Such capabilities are made possible by COSI's germanium cross-strip detectors, which provide high efficiency, high resolution spectroscopy and precise 3D positioning of photon interactions. Science goals for COSI include studies of 0.511 MeV emission from antimatter annihilation in the Galaxy, mapping radioactive elements from nucleosynthesis, determining emission mechanisms and source geometries with polarization, and detecting and localizing multimessenger sources. The instantaneous field of view (FOV) for the germanium detectors is >25% of the sky, and they are surrounded on the sides and bottom by active shields, providing background rejection as well as allowing for detection of gamma-ray bursts or other gamma-ray flares over >50% of the sky. We have completed a Phase A concept study to consider COSI as a Small Explorer (SMEX) satellite mission, and here we discuss the advances COSI-SMEX provides for astrophysics in the MeV bandpass.

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John A. Tomsick, Steven E. Boggs, Andreas Zoglauer, Eric Wulf, Lee Mitchell, Bernard Phlips, Clio Sleator, Terri Brandt, Albert Shih, Jarred Roberts, Pierre Jean, Peter von Ballmoos, Juan Martinez Oliveros, Alan Smale, Carolyn Kierans, Dieter Hartmann, Mark Leising, Marco Ajello, Eric Burns, Chris Fryer, Pascal Saint-Hilaire, Julien Malzac, Fabrizio Tavecchio, Valentina Fioretti, Andrea Bulgarelli, Giancarlo Ghirlanda, Hsiang-Kuang Chang, Tadayuki Takahashi, Kazuhiro Nakazawa, Shigeki Matsumoto, Tom Melia, Thomas Siegert, Alexander Lowell, Hadar Lazar, Jacqueline Beechert, Hannah Gulick. 2021-09-21. The Compton Spectrometer and Imager Project for MeV Astronomy. https://arxiv.org/abs/2109.10403

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