SDSS-IV MaNGA: The spatial distribution of star formation and its dependence on mass, structure, and environment
Por:
Spindler A., Wake D., Belfiore F., Bershady M., Bundy K., Drory N., Masters K., Thomas D., Westfall K., Wild V.
Publicada:
1 ene 2018
Resumen:
We study the spatially resolved star formation of 1494 galaxies in the SDSS-IV MaNGA Survey. Star formation rates (SFRs) are calculated using a two-step process, using Ha in starforming regions and Dn4000 in regions identified as active galactic nucleus/low-ionization (nuclear) emission region [AGN/LI(N)ER] or lineless. The roles of secular and environmental quenching processes are investigated by studying the dependence of the radial profiles of specific star formation rate on stellar mass, galaxy structure, and environment. We report on the existence of 'centrally suppressed' galaxies, which have suppressed Specific Star Formation Rate (SSFR) in their cores compared to their discs. The profiles of centrally suppressed and unsuppressed galaxies are distributed in a bimodal way. Galaxies with high stellar mass and core velocity dispersion are found to be much more likely to be centrally suppressed than low-mass galaxies, and we show that this is related to morphology and the presence of AGN/LI(N)ER like emission. Centrally suppressed galaxies also display lower star formation at all radii compared to unsuppressed galaxies. The profiles of central and satellite galaxies are also compared, and we find that satellite galaxies experience lower specific star formation rates at all radii than central galaxies. This uniform suppression could be a signal of the stripping of hot halo gas in the process known as strangulation. We find that satellites are not more likely to be suppressed in their cores than centrals, indicating that the core suppression is an entirely internal process. We find no correlation between the local environment density and the profiles of star formation rate surface density. © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society.
Filiaciones:
Spindler A.:
School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, United Kingdom
Wake D.:
School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, United Kingdom
Department of Physics, University of North Carolina Asheville, One University Heights, Asheville, NC 28804, United States
Belfiore F.:
University of California Observatories - Lick Observatory, University of California Santa Cruz, 1156 High St., Santa Cruz, CA 95064, United States
Bershady M.:
Department of Astronomy, University of Wisconsin, 475 N. Charter St., Madison, WI 53706, United States
Bundy K.:
University of California Observatories - Lick Observatory, University of California Santa Cruz, 1156 High St., Santa Cruz, CA 95064, United States
Drory N.:
McDonald Observatory, University of Texas at Austin, 1 University Station, Austin, TX 78712-0259, United States
Masters K.:
Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX, United Kingdom
Thomas D.:
Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth, PO1 3FX, United Kingdom
Westfall K.:
University of California Observatories - Lick Observatory, University of California Santa Cruz, 1156 High St., Santa Cruz, CA 95064, United States
Wild V.:
School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, KY16 9SS, United Kingdom
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