The SAMI Galaxy Survey: Gas streaming and dynamical M/L in rotationally supported systems ...

• Main Authors: Cecil, G., Fogarty, L. M. R., Richards, S., Bland-Hawthorn, J., Lange, R., Moffett, A., Catinella, Barbara, Cortese, Luca, Ho, I.-T., Taylor, Edward, Bryant, J. J., Allen, J. T., Sweet, Sarah, Croom, S. M., Driver, S. P., Goodwin, M., Kelvin, L., Green, A. W., Konstantopoulos, I. S., Owers, M. S., Lawrence, J. S., Lorente, N. P. F.
• Format: Text
• Language: unknown
• Published: Swinburne 2024
• Subjects: Cosmology and extragalactic astronomy; sami
• Online Access: https://dx.doi.org/10.25916/sut.26243774; https://figshare.swinburne.edu.au/articles/journal_contribution/The_SAMI_Galaxy_Survey_Gas_streaming_and_dynamical_M_L_in_rotationally_supported_systems/26243774

Line-of-sight velocities of gas and stars can constrain dark matter (DM) within rotationally supported galaxies if they trace circular orbits extensively. Photometric asymmetries may signify non-circular motions, requiring spectra with dense spatial coverage. Our integral-field spectroscopy of 178 galaxies spanned the mass range of the Sydney-AAO Multi-object integral field spectrograph (SAMI) Galaxy Survey. We derived circular speed curves (CSCs) of gas and stars from non-parametric fits out to r ∼ 2re. For 12/14 with measured H I profiles, ionized gas and H I maximum velocities agreed. We fitted mass-follows-light models to 163 galaxies by approximating the radial light profile as nested, very flattened mass homeoids viewed as a Sérsic form. Fitting broad-band spectral energy distributions to Sloan Digital Sky Survey images gave median stellar mass/light 1.7 assuming a Kroupa initial mass function (IMF) versus 2.6 dynamically. Two-thirds of the dynamical mass/light measures were consistent with ...