The SAMI Galaxy Survey: Mass and Environment as Independent Drivers of Galaxy Dynamics

Autor: K. E. Harborne, Joss Bland-Hawthorn, Sam P. Vaughan, Luca Cortese, Angel R. Lopez-Sanchez, Anne M. Medling, Richard M. McDermid, Matt S. Owers, Julia J. Bryant, Samuel N. Richards, Sarah M. Sweet, Francesco D'Eugenio, Claudia del P. Lagos, Scott M. Croom, Sarah Brough, Caroline Foster, Jesse van de Sande, Barbara Catinella, Nicholas Scott, Brent Groves
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Popis: The kinematic morphology-density relation of galaxies is normally attributed to a changing distribution of galaxy stellar masses with the local environment. However, earlier studies were largely focused on slow rotators; the dynamical properties of the overall population in relation to environment have received less attention. We use the SAMI Galaxy Survey to investigate the dynamical properties of $\sim$1800 early and late-type galaxies with $\log(M_*/M_{\odot})>9.5$ as a function of mean environmental overdensity ($\Sigma_{5}$) and their rank within a group or cluster. By classifying galaxies into fast and slow rotators, at fixed stellar mass above $\log(M_*/M_{\odot})>10.5$, we detect a higher fraction ($\sim3.4\sigma$) of slow rotators for group and cluster centrals and satellites as compared to isolated-central galaxies. Focusing on the fast-rotator population, we also detect a significant correlation between galaxy kinematics and their stellar mass as well as the environment they are in. Specifically, by using inclination-corrected or intrinsic $\lambda_{R_e}$ values, we find that, at fixed mass, satellite galaxies on average have the lowest $\lambda_{\,R_e,intr}$, isolated-central galaxies have the highest $\lambda_{\,R_e,intr}$, and group and cluster centrals lie in between. Similarly, galaxies in high-density environments have lower mean $\lambda_{\,R_e,intr}$ values as compared to galaxies at low environmental density. However, at fixed $\Sigma_{5}$, the mean $\lambda_{\,R_e,intr}$ differences for low and high-mass galaxies are of similar magnitude as when varying $\Sigma_{5}$ {($\Delta \lambda_{\,R_e,intr} \sim 0.05$. Our results demonstrate that after stellar mass, environment plays a significant role in the creation of slow rotators, while for fast rotators we also detect an independent, albeit smaller, impact of mass and environment on their kinematic properties.
Comment: 22 pages and 17 figures, accepted for publication in MNRAS. Abstract abridged for Arxiv. The key figures of the paper are: 6, 8, 10, and 12
Databáze: OpenAIRE