Séminaire IPAG

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Mapping the Galactic Centre for gamma-ray astronomy: Gas distribution and cosmic rays

jeudi 10 septembre 2026 - 11h00

Sruthiranjani Ravikularaman - AIRUB, Bochum
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The Central Molecular Zone (CMZ) at the centre of our Galaxy is a unique environment due to the extreme physical conditions and the presence of a supermassive Black Hole. It is also a region with a high concentration of cosmic-ray accelerators, making the Galactic Centre the brightest region in the gamma-ray sky. Since most of this emission is produced by the interactions of cosmic-ray protons with the ambient gas, the morphology of the gas is an important source of uncertainty when interpreting the gamma-ray emission. An independent model of the gas distribution is therefore necessary. To construct a 3D model of the gas distribution, we combine molecular line emission from CO isotopologues and atomic Hydrogen. Using modern clustering techniques, we efficiently remove contamination from the gas in the Galactic disk and identify structures in the gas in the CMZ. Here, I present the method and some of the major results of this study including the total mass of the CMZ gas, the approximate 3D locations of different structures in the CMZ and finally the implications for the CR distribution.

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