TY - JOUR
T1 - Quenching time-scales of galaxies in the eagle simulations
AU - Wright, Ruby J.
AU - Lagos, Claudia Del P.
AU - Davies, Luke J. M.
AU - Power, Chris
AU - Trayford, James W.
AU - Ivy Wong, O.
N1 - Funding Information:
We thank Camila Correa for her valuable scientific input and sharing a submitted version of her manuscript. RW is funded by a Postgraduate Research Scholarship from UWA. CL has received funding from a Discovery Early Career Researcher Award (DE150100618) and by the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. We also thanks the Research Collaboration Awards at UWA in its 2018 program, which funded the visit of Dr. James Trayford to ICRAR. We acknowledge the Virgo Consortium for making their simulation data available. The EAGLE simulations were performed using the DiRAC-2 facility at Durham, managed by the ICC, and the PRACE facility Curie based in France at TGCC, CEA, Bruyeres-le-Chatel.
Funding Information:
We thank Camila Correa for her valuable scientific input and sharing a submitted version of her manuscript. RW is funded by a Postgraduate Research Scholarship from UWA. CL has received funding from a Discovery Early Career Researcher Award (DE150100618) and by the ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D), through project number CE170100013. We also thanks the Research Collaboration Awards at UWA in its 2018 program, which funded the visit of Dr. James Trayford to ICRAR. We acknowledge the Virgo Consortium for making their simulation data available. The EAGLE simulations were performed using the DiRAC-2 facility at Durham, managed by the ICC, and the PRACE facility Curie based in France at TGCC, CEA, Bruyeresle-Chatel.
Publisher Copyright:
© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2019/8/1
Y1 - 2019/8/1
N2 - We use the eagle simulations to study the connection between the quenching time-scale, τQ, and the physical mechanisms that transform star-forming galaxies into passive galaxies. By quantifying τQ in two complementary ways-as the time over which (i) galaxies traverse the green valley on the colour-mass diagram, or (ii) leave the main sequence of star formation and subsequently arrive on the passive cloud in specific star formation rate (SSFR)-mass space-we find that the τQ distribution of high-mass centrals, low-mass centrals, and satellites are divergent. In the low stellar mass regime where M < 109.6 M·, centrals exhibit systematically longer quenching time-scales than satellites (≈4 Gyr compared to ≈2 Gyr). Satellites with low stellar mass relative to their halo mass cause this disparity, with ram pressure stripping quenching these galaxies rapidly. Low-mass centrals are quenched as a result of stellar feedback, associated with long τQ 3 Gyr. At intermediate stellar masses where $109.7< M☆ < 1010.3M⊙, τQ are the longest for both centrals and satellites, particularly for galaxies with higher gas fractions. At M☆1010.3M⊙, galaxy merger counts and black hole activity increase steeply for all galaxies. Quenching time-scales for centrals and satellites decrease with stellar mass in this regime to τQ2 Gyr. In anticipation of new intermediate redshift observational galaxy surveys, we analyse the passive and star-forming fractions of galaxies across redshift, and find that the τQ peak at intermediate stellar masses is responsible for a peak (inflection point) in the fraction of green valley central (satellite) galaxies at z ≈ 0.5-0.7.
AB - We use the eagle simulations to study the connection between the quenching time-scale, τQ, and the physical mechanisms that transform star-forming galaxies into passive galaxies. By quantifying τQ in two complementary ways-as the time over which (i) galaxies traverse the green valley on the colour-mass diagram, or (ii) leave the main sequence of star formation and subsequently arrive on the passive cloud in specific star formation rate (SSFR)-mass space-we find that the τQ distribution of high-mass centrals, low-mass centrals, and satellites are divergent. In the low stellar mass regime where M < 109.6 M·, centrals exhibit systematically longer quenching time-scales than satellites (≈4 Gyr compared to ≈2 Gyr). Satellites with low stellar mass relative to their halo mass cause this disparity, with ram pressure stripping quenching these galaxies rapidly. Low-mass centrals are quenched as a result of stellar feedback, associated with long τQ 3 Gyr. At intermediate stellar masses where $109.7< M☆ < 1010.3M⊙, τQ are the longest for both centrals and satellites, particularly for galaxies with higher gas fractions. At M☆1010.3M⊙, galaxy merger counts and black hole activity increase steeply for all galaxies. Quenching time-scales for centrals and satellites decrease with stellar mass in this regime to τQ2 Gyr. In anticipation of new intermediate redshift observational galaxy surveys, we analyse the passive and star-forming fractions of galaxies across redshift, and find that the τQ peak at intermediate stellar masses is responsible for a peak (inflection point) in the fraction of green valley central (satellite) galaxies at z ≈ 0.5-0.7.
KW - galaxies: evolution
KW - galaxies: formation
UR - http://www.scopus.com/inward/record.url?scp=85070081722&partnerID=8YFLogxK
U2 - 10.1093/mnras/stz1410
DO - 10.1093/mnras/stz1410
M3 - Article
AN - SCOPUS:85070081722
SN - 0035-8711
VL - 487
SP - 3740
EP - 3758
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -