Redshift evolution of the dynamical properties of massive galaxies from SDSS-III/BOSS

Alessandra Beifiori; Daniel Thomas; Claudia Maraston; Oliver Steele; Karen L. Masters; Janine Pforr; Roberto P. Saglia; Ralf Bender; Rita Tojeiro; Yan-Mei Chen; Adam Bolton; Joel R. Brownstein; Jonas Johansson; Alexie Leauthaud; Robert C. Nichol; Donald P. Schneider; Robert Senger; Ramin Skibba; David Wake; Kaike Pan; Stephanie Snedden; Dmitry Bizyaev; Howard Brewington; Viktor Malanushenko; Elena Malanushenko; Daniel Oravetz; Audrey Simmons; Alaina Shelden; Garrett Ebelke

doi:10.1088/0004-637x/789/2/92

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arXiv · 1405.1431

Redshift evolution of the dynamical properties of massive galaxies from SDSS-III/BOSS

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Abstract

We study the redshift evolution of the dynamical properties of ~180,000 massive galaxies from SDSS-III/BOSS combined with a local early-type galaxy sample from SDSS-II in the redshift range 0.1 2sigma significance. By combining our sample with high-redshift literature data we find that this evolution of the dynamical to stellar mass ratio continues beyond z~0.7 up to z>2 as Mdyn/Mstar~ (1+z)^{-0.30+/- 0.12} further strengthening the evidence for an increase of Mdyn/Mstar with cosmic time. This result is in line with recent predictions from galaxy formation simulations based on minor merger driven mass growth, in which the dark matter fraction within the half-light radius increases with cosmic time.

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Alessandra Beifiori, Daniel Thomas, Claudia Maraston, Oliver Steele, Karen L. Masters, Janine Pforr, Roberto P. Saglia, Ralf Bender, Rita Tojeiro, Yan-Mei Chen, Adam Bolton, Joel R. Brownstein, Jonas Johansson, Alexie Leauthaud, Robert C. Nichol, Donald P. Schneider, Robert Senger, Ramin Skibba, David Wake, Kaike Pan, Stephanie Snedden, Dmitry Bizyaev, Howard Brewington, Viktor Malanushenko, Elena Malanushenko, Daniel Oravetz, Audrey Simmons, Alaina Shelden, Garrett Ebelke. 2014-05-06. Redshift evolution of the dynamical properties of massive galaxies from SDSS-III/BOSS. https://doi.org/10.1088/0004-637x%2F789%2F2%2F92

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