The Morphology of Galaxies in the Baryon Oscillation Spectroscopic Survey

Autor: Masters, Karen L., Maraston, Claudia, Nichol, Robert C., Thomas, Daniel, Beifiori, Alessandra, Bundy, Kevin, Edmondson, Edward M., Higgs, Tim D., Leauthaud, Alexie, Mandelbaum, Rachel, Pforr, Janine, Ross, Ashley J., Ross, Nicholas P., Schneider, Donald P., Skibba, Ramin, Tinker, Jeremy, Tojeiro, Rita, Wake, David, Brinkmann, Jon, Weaver, Benjamin A.
Rok vydání: 2011
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1111/j.1365-2966.2011.19557.x
Popis: We study the morphology of luminous and massive galaxies at 0.32.35 selects a sub-sample of BOSS galaxies with 90% early-type morphology - more comparable to the earlier Luminous Red Galaxy (LRG) samples of SDSS-I/II. The remaining 10% of galaxies above this cut have a late-type morphology and may be analogous to the "passive spirals" found at lower redshift. We find that 23+/-4% of the early-type galaxies are unresolved multiple systems in the SDSS imaging. We estimate that at least 50% of these are real associations (not projection effects) and may represent a significant "dry merger" fraction. We study the SDSS pipeline sizes of BOSS galaxies which we find to be systematically larger (by 40%) than those measured from HST images, and provide a statistical correction for the difference. These details of the BOSS galaxies will help users of the data fine-tune their selection criteria, dependent on their science applications. For example, the main goal of BOSS is to measure the cosmic distance scale and expansion rate of the Universe to percent-level precision - a point where systematic effects due to the details of target selection may become important.
Comment: 18 pages, 11 figures; v2 as accepted by MNRAS
Databáze: arXiv