Preprocessing among the Infalling Galaxy Population of EDisCS Clusters
Autor: | Douglas Clowe, Gabriella De Lucia, Alfonso Aragón-Salamanca, Bianca M. Poggianti, Fuyan Bian, John Moustakas, Gregory Rudnick, Kelley Liebst, Pascale Jablonka, Dennis W. Just, Matthew Kirby, Richard J. Cool, Tyler D. Desjardins, Claire Halliday, Rose Finn, Justin L. Mann, Dennis Zaritsky, Vandana Desai |
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Přispěvatelé: | Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) |
Jazyk: | angličtina |
Rok vydání: | 2019 |
Předmět: |
010504 meteorology & atmospheric sciences
Population FOS: Physical sciences Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics 01 natural sciences large-scale structure environmental dependence 0103 physical sciences evolution Cluster (physics) galaxies: interactions Astrophysics::Solar and Stellar Astrophysics education 010303 astronomy & astrophysics Galaxy cluster Astrophysics::Galaxy Astrophysics ComputingMilieux_MISCELLANEOUS 0105 earth and related environmental sciences Physics [PHYS]Physics [physics] education.field_of_study Star formation weak lensing observations Velocity dispersion Astronomy and Astrophysics Radius Astrophysics - Astrophysics of Galaxies Galaxy Redshift morphology-density relation velocity dispersions dark-matter Space and Planetary Science star-formation rates Astrophysics of Galaxies (astro-ph.GA) digital sky survey galaxies: distances and redshifts stellar mass galaxies: evolution [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
Zdroj: | The Astrophysical Journal The Astrophysical Journal, American Astronomical Society, 2019, 885 (1), pp.6. ⟨10.3847/1538-4357/ab44a0⟩ |
ISSN: | 0004-637X 1538-4357 |
Popis: | We present results from a low-resolution spectroscopic survey for 21 galaxy clusters at $0.4 < z < 0.8$ selected from the ESO Distant Cluster Survey. We measured spectra using the low-dispersion prism in IMACS on the Magellan Baade telescope and calculate redshifts with an accuracy of $\sigma_z = 0.007$. We find 1763 galaxies that are brighter than $R = 22.9$ in the large-scale cluster environs. We identify the galaxies expected to be accreted by the clusters as they evolve to $z = 0$ using spherical infall models and find that $\sim30\%$ to $\sim70\%$ of the $z = 0$ cluster population lies outside the virial radius at $z \sim 0.6$. For analogous clusters at $z = 0$, we calculate that the ratio of galaxies that have fallen into the clusters since $z \sim 0.6$ to those that were already in the core at that redshift is typically between $\sim0.3$ and $1.5$. This wide range of ratios is due to intrinsic scatter and is not a function of velocity dispersion, so a variety of infall histories is to be expected for clusters with current velocity dispersions of $300 \lesssim\sigma\lesssim 1200$ km s$^{-1}$. Within the infall regions of $z \sim 0.6$ clusters, we find a larger red fraction of galaxies than in the field and greater clustering among red galaxies than blue. We interpret these findings as evidence of "preprocessing", where galaxies in denser local environments have their star formation rates affected prior to their aggregation into massive clusters, although the possibility of backsplash galaxies complicates the interpretation. Comment: Accepted for publication in ApJ |
Databáze: | OpenAIRE |
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