1. SAMI Galaxy Survey: observing the environmental quenching of star formation in GAMA groups.
- Author
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Schaefer, A L, Croom, S M, Scott, N, Brough, S, Allen, J T, Bekki, K, Bland-Hawthorn, J, Bloom, J V, Bryant, J J, Cortese, L, Davies, L J M, Federrath, C, Fogarty, L M R, Green, A W, Groves, B, Hopkins, A M, Konstantopoulos, I S, López-Sánchez, A R, Lawrence, J S, and McElroy, R E
- Subjects
STAR formation ,GALACTIC evolution ,STELLAR mass ,RADIAL distribution function ,DENSITY of stars - Abstract
We explore the radial distribution of star formation in galaxies in the SAMI Galaxy Survey as a function of their Local Group environment. Using a sample of galaxies in groups (with halo masses less than |$\simeq 10^{14} \, \mathrm{M_{\odot }}$|) from the Galaxy And Mass Assembly Survey, we find signatures of environmental quenching in high-mass groups (|$M_{\mathrm{ G}}\, \gt\, 10^{12.5} \, \mathrm{M_{\odot }}$|). The mean integrated specific star formation rate (sSFR) of star-forming galaxies in high-mass groups is lower than for galaxies in low-mass groups or those that are ungrouped, with |$\Delta \log (\mathrm{ sSFR}/\mathrm{yr^{-1}}) \,=\, 0.45 \pm 0.07$|. This difference is seen at all galaxy stellar masses. In high-mass groups, star-forming galaxies more massive than |$M_{*} \sim 10^{10} \, \mathrm{M_{\odot }}$| have centrally concentrated star formation. These galaxies also lie below the star formation main sequence, which suggests they may be undergoing outside-in quenching. Lower mass galaxies in high-mass groups do not show evidence of concentrated star formation. In groups less massive than |$M_{\mathrm{ G}} = 10^{12.5} \, \mathrm{M_{\odot }}$|, we do not observe these trends. In this regime, we find a modest correlation between centrally concentrated star formation and an enhancement in the total star formation rate, consistent with triggered star formation in these galaxies. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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