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arXiv · 2411.12210

Moderate Influence of Halo Spin on Stellar Mass Distributions in Dwarf and Massive Galaxies

Yu Rong·Zichen Hua·Huijie Hu
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Abstract

We estimate halo spins for HI-rich galaxies in the Arecibo Legacy Fast Alfa Survey using a semi-analytic approach, examining the relationship between halo spin and stellar surface density. Our findings reveal an inverse correlation in both low- and high-mass galaxy samples, with stellar surface density decreasing as halo spin increases. This trend highlights the pivotal role of halo spin in galaxy evolution and suggests a universal formation scenario: high-spin halos, accompanied by high-spin accreted gas, retain angular momentum, preventing gas from efficiently condensing in the galactic center and thus suppressing star formation. Consequently, weak feedback redistributes gas to the halo outskirts without significant expulsion. The shallower central gravitational potential in high-spin halos promotes outward stellar migration, leading to more extended stellar distributions and lower stellar surface densities.

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Yu Rong, Zichen Hua, Huijie Hu. 2024-11-19. Moderate Influence of Halo Spin on Stellar Mass Distributions in Dwarf and Massive Galaxies. https://arxiv.org/abs/2411.12210

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