The SAMI Galaxy Survey: mass–kinematics scaling relations

• Published in: Monthly Notices of the Royal Astronomical Society
• Main Authors: Barat, Dilyar, D’Eugenio, Francesco, Colless, Matthew, Brough, Sarah, Catinella, Barbara, Cortese, Luca, Croom, Scott M, Medling, Anne M, Oh, Sree, van de Sande, Jesse, Sweet, Sarah M, Yi, Sukyoung K, Bland-Hawthorn, Joss, Bryant, Julia, Goodwin, Michael, Groves, Brent, Lawrence, Jon, Owers, Matt S, Richards, Samuel N, Scott, Nicholas
• Other Authors: University of Sydney, Australian Astronomical Observatory, Australian Research Council, European Research Council, National Aeronautics and Space Administration, Space Telescope Science Institute, Yonsei University
• Format: Article in Journal/Newspaper
• Language: English
• Published: Oxford University Press (OUP) 2019
• Subjects: sami
• Online Access: http://dx.doi.org/10.1093/mnras/stz1439; http://academic.oup.com/mnras/advance-article-pdf/doi/10.1093/mnras/stz1439/28701525/stz1439.pdf; http://academic.oup.com/mnras/article-pdf/487/2/2924/28830161/stz1439.pdf

ABSTRACT We use data from the Sydney-AAO Multi-object Integral-field spectroscopy (SAMI) Galaxy Survey to study the dynamical scaling relation between galaxy stellar mass M∗ and the general kinematic parameter $S_K = \sqrt{K V_{\rm rot}^2 + \sigma ^2}$ that combines rotation velocity Vrot and velocity dispersion σ. We show that the log M∗ – log SK relation: (1) is linear above limits set by properties of the samples and observations; (2) has slightly different slope when derived from stellar or gas kinematic measurements; (3) applies to both early-type and late-type galaxies and has smaller scatter than either the Tully–Fisher relation (log M∗ − log Vrot) for late types or the Faber–Jackson relation (log M∗ − log σ) for early types; and (4) has scatter that is only weakly sensitive to the value of K, with minimum scatter for K in the range 0.4 and 0.7. We compare SK to the aperture second moment (the ‘aperture velocity dispersion’) measured from the integrated spectrum within a 3-arcsecond radius aperture ($\sigma _{3^{\prime \prime }}$). We find that while SK and $\sigma _{3^{\prime \prime }}$ are in general tightly correlated, the log M∗ − log SK relation has less scatter than the $\log M_* - \log \sigma _{3^{\prime \prime }}$ relation.