The MAGPI Survey: the evolution and drivers of gas turbulence in intermediate-redshift galaxies ...

• Main Authors: Mai, Yifan, Croom, Scott M., Wisnioski, Emily, Vaughan, Sam P., Varidel, Mathew R., Battisti, Andrew J., Mendel, J. Trevor, Mun, Marcie, Tsukui, Takafumi, Foster, Caroline, Harborne, Katherine E., Lagos, Claudia D. P., Wang, Di, Bellstedt, Sabine, Bland-Hawthorn, Joss, Colless, Matthew, D'Eugenio, Francesco, Grasha, Kathryn, Peng, Yingjie, Santucci, Giulia, Sweet, Sarah M., Thater, Sabine, Valenzuela, Lucas M., Ziegler, Bodo
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: arXiv 2024
• Subjects: Astrophysics of Galaxies astro-ph.GA; FOS: Physical sciences; sami
• Online Access: https://dx.doi.org/10.48550/arxiv.2408.12224; https://arxiv.org/abs/2408.12224

We measure the ionised gas velocity dispersions of star-forming galaxies in the MAGPI survey ($z\sim0.3$) and compare them with galaxies in the SAMI ($z\sim0.05$) and KROSS ($z\sim1$) surveys to investigate how the ionised gas velocity dispersion evolves. For the first time, we use a consistent method that forward models galaxy kinematics from $z=0$ to $z=1$. This method accounts for spatial substructure in emission line flux and beam smearing. We investigate the correlation between gas velocity dispersion and galaxy properties to understand the mechanisms that drive gas turbulence. We find that in both MAGPI and SAMI galaxies, the gas velocity dispersion more strongly correlates with the star-formation rate surface density ($Σ_{\rm SFR}$) than with a variety of other physical properties, and the average gas velocity dispersion is similar, at the same $Σ_{\rm SFR}$, for SAMI, MAGPI and KROSS galaxies. The results indicate that mechanisms related to $Σ_{\rm SFR}$ could be the dominant driver of gas turbulence ... : 15 pages, 10 figures, accepted for publication in MNRAS ...