Accepted author manuscript, 1.08 MB, PDF document
Available under license: CC BY: Creative Commons Attribution 4.0 International License
Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Galaxy Zoo
T2 - the interplay of quenching mechanisms in the group environment
AU - Smethurst, R. J.
AU - Lintott, C. J.
AU - Bamford, S. P.
AU - Hart, R. E.
AU - Kruk, S. J.
AU - Masters, K. L.
AU - Nichol, R. C.
AU - Simmons, B. D.
PY - 2017/8/11
Y1 - 2017/8/11
N2 - Does the environment of a galaxy directly influence the quenching history of a galaxy? Here, we investigate the detailed morphological structures and star formation histories of a sample of SDSS group galaxies with both classifications from Galaxy Zoo 2 and near ultra-violet (NUV) detections in GALEX. We use the optical and NUV colours to infer the quenching time and rate describing a simple exponentially declining star formation history for each galaxy, along with a control sample of field galaxies. We find that the time since quenching and the rate of quenching do not correlate with the relative velocity of a satellite but are correlated with the group potential. This quenching occurs within an average quenching time-scale of ∼ 2.5 Gyr from star forming to complete quiescence, during an average infall time (from ∼10R200 to 0.01R200) of ∼ 2.6 Gyr. Our results suggest that the environment does play a direct role in galaxy quenching through quenching mechanisms that are correlated with the group potential, such as harassment, interactions or starvation. Environmental quenching mechanisms that are correlated with satellite velocity, such as ram-pressure stripping, are not the main cause of quenching in the group environment. We find that no single mechanism dominates over another, except in the most extreme environments or masses. Instead, an interplay of mergers, mass and morphological quenching and environment-driven quenching mechanisms dependent on the group potential drive galaxy evolution in groups.
AB - Does the environment of a galaxy directly influence the quenching history of a galaxy? Here, we investigate the detailed morphological structures and star formation histories of a sample of SDSS group galaxies with both classifications from Galaxy Zoo 2 and near ultra-violet (NUV) detections in GALEX. We use the optical and NUV colours to infer the quenching time and rate describing a simple exponentially declining star formation history for each galaxy, along with a control sample of field galaxies. We find that the time since quenching and the rate of quenching do not correlate with the relative velocity of a satellite but are correlated with the group potential. This quenching occurs within an average quenching time-scale of ∼ 2.5 Gyr from star forming to complete quiescence, during an average infall time (from ∼10R200 to 0.01R200) of ∼ 2.6 Gyr. Our results suggest that the environment does play a direct role in galaxy quenching through quenching mechanisms that are correlated with the group potential, such as harassment, interactions or starvation. Environmental quenching mechanisms that are correlated with satellite velocity, such as ram-pressure stripping, are not the main cause of quenching in the group environment. We find that no single mechanism dominates over another, except in the most extreme environments or masses. Instead, an interplay of mergers, mass and morphological quenching and environment-driven quenching mechanisms dependent on the group potential drive galaxy evolution in groups.
U2 - 10.1093/mnras/stx973
DO - 10.1093/mnras/stx973
M3 - Journal article
VL - 469
SP - 3670
EP - 3687
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 3
ER -