Quantifying the Relationship Between Galaxy Specific Star Formation Rate And Halo Spin For Star-forming Galaxies

TL;DR

This study examines the link between galaxy star formation rates and halo spin using ALFALFA HI data, revealing a weak positive correlation that informs galaxy formation theories.

Contribution

It provides the first observational evidence of a positive correlation between specific star formation rate and halo spin in star-forming galaxies, highlighting discrepancies with simulations.

Findings

Higher halo spin correlates with increased sSFR.

Galaxies with higher spin have more gas-rich, colder disks.

Results challenge current cosmological simulation models.

Abstract

Utilizing ALFALFA HI data, we investigate the relationship between specific star formation rate (sSFR) and halo spin across various star-forming galaxies. Our analysis reveals weak yet statistically significant positive correlation between sSFR and halo spin, irrespective of the galactic environment. This trend suggests that galaxies with higher spin parameters tend to host dynamically colder, gas-rich disks, sustaining elevated gas surface densities and prolonged star formation. These findings align with theoretical expectations of angular momentum-regulated gas accretion but highlight discrepancies with cosmological simulations, underscoring unresolved challenges in modeling baryonic feedback and star formation efficiency.