%0 Generic %1 trayford2016being %A Trayford, James. W. %A Theuns, Tom %A Bower, Richard G. %A Crain, Robert A. %A Lagos, Claudia del P. %A Schaller, Matthieu %A Schaye, Joop %D 2016 %K bimodality color quenching simulation %T It's not easy being green: The evolution of galaxy colour in the EAGLE simulation %U http://arxiv.org/abs/1601.07907 %X We examine the evolution of intrinsic u-r colours of galaxies in the EAGLE cosmological hydrodynamical simulations, which has been shown to reproduce the observed redshift z=0.1 colour-magnitude distribution well. The median u-r of star-forming ('blue cloud') galaxies reddens by 1 mag from z=2 to 0 at fixed stellar mass, as their specific star formation rates decrease with time. A red sequence starts to build-up around z=1, due to the quenching of low-mass satellite galaxies at the faint end, and due to the quenching of more massive central galaxies by their active galactic nuclei (AGN) at the bright end. This leaves a dearth of intermediate-mass red sequence galaxies at z=1, which is mostly filled in by z=0. We quantify the time-scales of colour transition due to satellite and AGN quenching, finding that most galaxies spend less than 2 Gyr in the 'green valley'. On examining the trajectories of galaxies in a colour-stellar mass diagram, we identify three characteristic tracks that galaxies follow (quiescently star-forming, quenching and rejuvenating galaxies) and quantify the fraction of galaxies that follow each track.

@misc{trayford2016being, abstract = {We examine the evolution of intrinsic u-r colours of galaxies in the EAGLE cosmological hydrodynamical simulations, which has been shown to reproduce the observed redshift z=0.1 colour-magnitude distribution well. The median u-r of star-forming ('blue cloud') galaxies reddens by 1 mag from z=2 to 0 at fixed stellar mass, as their specific star formation rates decrease with time. A red sequence starts to build-up around z=1, due to the quenching of low-mass satellite galaxies at the faint end, and due to the quenching of more massive central galaxies by their active galactic nuclei (AGN) at the bright end. This leaves a dearth of intermediate-mass red sequence galaxies at z=1, which is mostly filled in by z=0. We quantify the time-scales of colour transition due to satellite and AGN quenching, finding that most galaxies spend less than 2 Gyr in the 'green valley'. On examining the trajectories of galaxies in a colour-stellar mass diagram, we identify three characteristic tracks that galaxies follow (quiescently star-forming, quenching and rejuvenating galaxies) and quantify the fraction of galaxies that follow each track.}, added-at = {2016-02-01T10:10:11.000+0100}, author = {Trayford, James. W. and Theuns, Tom and Bower, Richard G. and Crain, Robert A. and Lagos, Claudia del P. and Schaller, Matthieu and Schaye, Joop}, biburl = {https://www.bibsonomy.org/bibtex/283da89f9cf8784f2e9e39dc97c9789c4/miki}, description = {[1601.07907] It's not easy being green: The evolution of galaxy colour in the EAGLE simulation}, interhash = {0a67a1ee87f5ef1e7ddfb5d53eee164d}, intrahash = {83da89f9cf8784f2e9e39dc97c9789c4}, keywords = {bimodality color quenching simulation}, note = {cite arxiv:1601.07907Comment: 15 pages, 10 figures. Submitted to MNRAS. All comments welcome. Larger version of Fig. 1 included in source. For the animated evolution of the EAGLE intrinsic u-r CMD (with central and satellite galaxies coloured red and blue respectively) see http://community.dur.ac.uk/j.w.trayford/media/CMD_evolution_EAGLE.mp4}, timestamp = {2016-02-01T10:10:11.000+0100}, title = {It's not easy being green: The evolution of galaxy colour in the EAGLE simulation}, url = {http://arxiv.org/abs/1601.07907}, year = 2016 }