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arXiv · 0804.1774

Inverse Compton Origin of the Hard X-Ray and Soft Gamma-Ray Emission from the Galactic Ridge

Troy A. Porter·Igor V. Moskalenko·Andrew W. Strong·Elena Orlando·Laurent Bouchet
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Abstract

A recent re-determination of the non-thermal component of the hard X-ray to soft gamma-ray emission from the Galactic ridge, using the SPI instrument on the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) Observatory, is shown to be well reproduced as inverse-Compton emission from the interstellar medium. Both cosmic-ray primary electrons and secondary electrons and positrons contribute to the emission. The prediction uses the GALPROP model and includes a new calculation of the interstellar radiation field. This may solve a long-standing mystery of the origin of this emission, and potentially opens a new window on Galactic cosmic rays.

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Troy A. Porter, Igor V. Moskalenko, Andrew W. Strong, Elena Orlando, Laurent Bouchet. 2008-04-10. Inverse Compton Origin of the Hard X-Ray and Soft Gamma-Ray Emission from the Galactic Ridge. https://doi.org/10.1086/589615

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