THE SAMI GALAXY SURVEY: REVISITING GALAXY CLASSIFICATION THROUGH HIGH-ORDER STELLAR KINEMATICS ...

• Main Authors: Richards, Samuel N., Davies, Roger, Taranu, Dan, Allen, James T., Walcher, C. Jakob, Couch, Warrick J., McDermid, Richard M., Bland-Hawthorn, Joss, Lawrence, Jon S., Oh, Sree, Konstantopoulos, Iraklis S., Elahi, Pascal J., Scott, Nicholas, Groves, Brent, Ho, I-Ting, Foster, Caroline, D'Eugenio, Francesco, Cecil, Gerald, Sweet, Sarah M., Brough, Sarah, Sharp, Rob, Goldstein, Gregory, Jeong, Hyunjin, Leslie, Sarah K., Cortese, Luca, Fogarty, Lisa M.R., López-Sánchez, Ángel R., Colless, Matthew, Van De Sande, Jesse, Schaefer, Adam L., Jones, D. Heath, McElroy, Rebecca, Goodwin, Michael, Yi, Sukyoung K., Medling, Anne M., Tonini, Chiara, Bryant, Julia J., Owers, Matt S., Croom, Scott M.
• Format: Text
• Language: English
• Published: The University of North Carolina at Chapel Hill University Libraries 2017
• Subjects: sami
• Online Access: https://dx.doi.org/10.17615/bdq6-nn61; https://cdr.lib.unc.edu/concern/articles/gx41mq09t

Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using 2D integral field data from the SAMI Galaxy Survey. A proxy for the spin parameter ($\lambda_{R_e}$) and ellipticity ($\epsilon_e$) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, respectively, as also seen in earlier studies. We confirm that regular rotators show a strong h3 versus $V/\sigma$ anti-correlation, whereas quasi-regular and non-regular rotators show a more vertical relation in h3 and $V/\sigma$. Motivated by recent cosmological simulations, we develop an alternative approach to kinematically classify galaxies from their individual h3 versus $V/\sigma$ signatures. We ...