Accepted author manuscript, 1.42 MB, PDF document
Accepted author manuscript
Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Near-ultraviolet signatures of environment-driven galaxy quenching in Sloan Digital Sky Survey groups
AU - Crossett, Jacob P.
AU - Pimbblet, Kevin A.
AU - Jones, D. Heath
AU - Brown, Michael J. I.
AU - Stott, John P.
PY - 2017/1
Y1 - 2017/1
N2 - We have investigated the effect of group environment on residual star formation in galaxies, using Galaxy Evolution Explorer near-ultraviolet (NUV) galaxy photometry with the Sloan Digital Sky Survey group catalogue of Yang et al. We compared the (NUV - r) colours of grouped and non-grouped galaxies, and find a significant increase in the fraction of red sequence galaxies with blue (NUV - r) colours outside of groups. When comparing galaxies in mass-matched samples of satellite (non-central), and non-grouped galaxies, we found a >4 sigma difference in the distribution of (NUV - r) colours, and an (NUV - r) blue fraction >3 sigma higher outside groups. A comparison of satellite and non-grouped samples has found the NUV fraction is a factor of similar to 2 lower for satellite galaxies between 10(10.5) and 10(10.7)M(circle dot), showing that higher mass galaxies are more likely to have residual star formation when not influenced by a group potential. There was a higher (NUV - r) blue fraction of galaxies with lower Sersic indices (n <3) outside of groups, not seen in the satellite sample. We have used stellar population models of Bruzual & Charlot with multiple burst, or exponentially declining star formation histories to find that many of the (NUV - r) blue non-grouped galaxies can be explained by a slow (similar to 2 Gyr) decay of star formation, compared to the satellite galaxies. We suggest that taken together, the difference in (NUV - r) colours between samples can be explained by a population of secularly evolving, non-grouped galaxies, where star formation declines slowly. This slow channel is less prevalent in group environments where more rapid quenching can occur.
AB - We have investigated the effect of group environment on residual star formation in galaxies, using Galaxy Evolution Explorer near-ultraviolet (NUV) galaxy photometry with the Sloan Digital Sky Survey group catalogue of Yang et al. We compared the (NUV - r) colours of grouped and non-grouped galaxies, and find a significant increase in the fraction of red sequence galaxies with blue (NUV - r) colours outside of groups. When comparing galaxies in mass-matched samples of satellite (non-central), and non-grouped galaxies, we found a >4 sigma difference in the distribution of (NUV - r) colours, and an (NUV - r) blue fraction >3 sigma higher outside groups. A comparison of satellite and non-grouped samples has found the NUV fraction is a factor of similar to 2 lower for satellite galaxies between 10(10.5) and 10(10.7)M(circle dot), showing that higher mass galaxies are more likely to have residual star formation when not influenced by a group potential. There was a higher (NUV - r) blue fraction of galaxies with lower Sersic indices (n <3) outside of groups, not seen in the satellite sample. We have used stellar population models of Bruzual & Charlot with multiple burst, or exponentially declining star formation histories to find that many of the (NUV - r) blue non-grouped galaxies can be explained by a slow (similar to 2 Gyr) decay of star formation, compared to the satellite galaxies. We suggest that taken together, the difference in (NUV - r) colours between samples can be explained by a population of secularly evolving, non-grouped galaxies, where star formation declines slowly. This slow channel is less prevalent in group environments where more rapid quenching can occur.
KW - galaxies:evolution
KW - galaxies:groups:general
KW - galaxies:photometry
KW - galaxies:star formation
KW - galaxies:stellar content
KW - ultraviolet:galaxies
KW - COLOR-MAGNITUDE RELATION
KW - MASS ASSEMBLY GAMA
KW - STAR-FORMATION HISTORIES
KW - RED-SEQUENCE GALAXIES
KW - CLUSTER GALAXIES
KW - S0 GALAXIES
KW - ELLIPTIC GALAXIES
KW - FORMATION RATES
KW - GREEN VALLEY
KW - ENERGY-DISTRIBUTIONS
U2 - 10.1093/mnras/stw2228
DO - 10.1093/mnras/stw2228
M3 - Journal article
VL - 464
SP - 480
EP - 490
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 1
ER -