%0 Generic %1 perezrafols2014crosscorrelation %A Pérez-Ràfols, Ignasi %A Miralda-Escudé, Jordi %A Lundgren, Britt %A Ge, Jian %A Petitjean, Patrick %A Schneider, Donald P. %A York, Donald G. %A Weaver, Benjamin A. %D 2014 %K absorption correlation galaxy mgII %T The Cross-correlation of MgII Absorption and Galaxies in BOSS %U http://arxiv.org/abs/1402.1342 %X We present a measurement of the cross-correlation of MgII absorption and massive galaxies, using the DR11 galaxy sample of the Baryon Oscillation Spectroscopic Survey of SDSS-III, and the DR7 quasar spectra of SDSS-II. The cross-correlation is measured by stacking quasar absorption spectra shifted to the redshift of galaxies that are within a certain impact parameter bin of the quasar, after dividing by a quasar continuum model. This results in an average MgII equivalent width as a function of impact parameter from a galaxy, ranging from 50 kpc to more than 10 Mpc in proper units, which includes all MgII absorbers. We show that special care needs to be taken to use an unbiased quasar continuum estimator, to avoid systematic errors in the measurement of the mean stacked MgII equivalent width. The measured cross-correlation follows the expected shape of the galaxy correlation function, although measurement errors are large. We use the cross-correlation amplitude to derive the bias factor of MgII absorbers, finding $b_MgII=1.500.19$, where the error accounts only for the statistical uncertainty in measuring the mean equivalent width. This result indicates that MgII absorbers at redshift $z0.5$ are spatially distributed on large scales similarly to galaxies with $L L_*$. Keywords: galaxies: haloes, galaxies: formation, quasars: absorption lines, large-scale structure of universe

@misc{perezrafols2014crosscorrelation, abstract = {We present a measurement of the cross-correlation of MgII absorption and massive galaxies, using the DR11 galaxy sample of the Baryon Oscillation Spectroscopic Survey of SDSS-III, and the DR7 quasar spectra of SDSS-II. The cross-correlation is measured by stacking quasar absorption spectra shifted to the redshift of galaxies that are within a certain impact parameter bin of the quasar, after dividing by a quasar continuum model. This results in an average MgII equivalent width as a function of impact parameter from a galaxy, ranging from 50 kpc to more than 10 Mpc in proper units, which includes all MgII absorbers. We show that special care needs to be taken to use an unbiased quasar continuum estimator, to avoid systematic errors in the measurement of the mean stacked MgII equivalent width. The measured cross-correlation follows the expected shape of the galaxy correlation function, although measurement errors are large. We use the cross-correlation amplitude to derive the bias factor of MgII absorbers, finding $b_{\mathrm{MgII}}=1.50\pm 0.19$, where the error accounts only for the statistical uncertainty in measuring the mean equivalent width. This result indicates that MgII absorbers at redshift $z\simeq 0.5$ are spatially distributed on large scales similarly to galaxies with $L \simeq L_{*}$. Keywords: galaxies: haloes, galaxies: formation, quasars: absorption lines, large-scale structure of universe}, added-at = {2014-02-07T09:46:03.000+0100}, author = {Pérez-Ràfols, Ignasi and Miralda-Escudé, Jordi and Lundgren, Britt and Ge, Jian and Petitjean, Patrick and Schneider, Donald P. and York, Donald G. and Weaver, Benjamin A.}, biburl = {https://www.bibsonomy.org/bibtex/201b6bfed8bcc34c457adbd8bc9c9c07d/miki}, description = {[1402.1342] The Cross-correlation of MgII Absorption and Galaxies in BOSS}, interhash = {ed083acdc420f2ad1178a009adc86d44}, intrahash = {01b6bfed8bcc34c457adbd8bc9c9c07d}, keywords = {absorption correlation galaxy mgII}, note = {cite arxiv:1402.1342Comment: Submitted to MNRAS on February 6; 14 figures, 37 pages (one column format)}, timestamp = {2014-02-07T09:46:03.000+0100}, title = {The Cross-correlation of MgII Absorption and Galaxies in BOSS}, url = {http://arxiv.org/abs/1402.1342}, year = 2014 }