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arXiv · 2502.17141

The Starburst Acceleration of High-Velocity Clouds in the Galactic Center

Mengfei Zhang·Miao Li·Peixin Zhu
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Abstract

High-velocity clouds (HVCs) in the Galactic center have garnered significant attention due to their mysterious formation, potentially linked to starburst events or supermassive black hole activity in the region. However, it remains challenging to explain the observed column density and velocity distribution of HVCs. The discovery of high-velocity molecular clouds (HVMCs), which are denser and more massive, adds to this complexity. To address this, we conduct three-dimensional numerical simulations to explore the origin and magneto-hydrodynamic evolution of HVCs in the context of a starburst in the Galactic center. By incorporating magnetic fields and an initial tangential velocity for the clouds, our simulation results align with the observed properties of HVCs, supporting the notion that these clouds can originate from a starburst process. In addition, ~5% of the total mass of initial clouds can survive after 3.5 Myr, as a result, the following star formation will be more efficient than a feedback process that destroys all cool clouds.

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Mengfei Zhang, Miao Li, Peixin Zhu. 2025-02-24. The Starburst Acceleration of High-Velocity Clouds in the Galactic Center. https://arxiv.org/abs/2502.17141

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