Probing the Galactic Diffuse Continuum Emission with COSI

Abstract

In 2016 the Compton Spectrometer and Imager (COSI) had a successful 46-day flight onboard NASA's Super Pressure Balloon platform. In this work we report measurements of the Galactic diffuse continuum emission (GDCE) observed towards the inner Galaxy during the flight, which in the COSI energy band (0.2 - 5 MeV) is primarily generated from inverse Compton radiation. Within uncertainties we find overall good agreement with previous measurements from INTEGRAL/SPI and COMPTEL. Based on these initial findings, we discuss the potential for further probing the GDCE with the 2016 COSI balloon data, as well as prospects for the upcoming satellite mission.

arXiv comment14 pages, 4 figures, 2 tables. Accepted for publication in the Astrophysical Journal

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Cited by in corpus (10)

• Anomalous Ionization in the Central Molecular Zone by sub-GeV Dark Matter
• Gamma-ray line emission from the Local Bubble
• Bottom-up Background Simulations of the 2016 COSI Balloon Flight
• Enhancing Compton telescope imaging with maximum a posteriori estimation: a modified Richardson-Lucy algorithm for the Compton Spectrometer and Imager
• Pre-flight Background Estimates for COSI
• The properties of the Galactic Hard X-Ray and soft gamma-ray Background based on 20 years of INTEGRAL/IBIS observations
• Imaging and Spectral Fitting of Bright Gamma-ray Sources with the COSI Balloon Payload
• Low-Energy Cosmic Rays and Associated MeV Gamma-Ray Emissions in the Protoplanetary System
• Constraining light dark matter in vector-scalar portals with COSI and AMEGO-X
• Diffuse continuum emission and large extended sources at MeV energies