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arXiv · 2610.40049

Can the $\sim 5$ kpc starburst ring in MW create eROSITA bubbles?

Mukesh Singh Bisht·Kartick C. Sarkar
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Abstract

eROSITA bubbles (eRBs) in our Galaxy are thought to be due to the energy injection by the central star-forming region or the central Super Massive Black Hole. Identifying the origin of these bubbles is crucial in constraining the origin of the Fermi Bubbles and the nature of the Galactic feedback. However, some recent opinions suggest that the eRBs may not even have been produced by any central source, but rather a result of a star-formation ring at $R\sim 5$ kpc. In this letter, we perform detailed hydrodynamic simulations to refute that claim and show that such a ring of star formation alone is not able to produce the symmetric eROSITA bubbles - one needs a compact energy injection from the Galactic Center to produce these bubbles. Our study, therefore, suggests that the eROSITA bubbles truly represent the nuclear outflow from our Galaxy.

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Mukesh Singh Bisht, Kartick C. Sarkar. 2026-10-29. Can the $\sim 5$ kpc starburst ring in MW create eROSITA bubbles?. https://arxiv.org/abs/2610.40049

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