The Dark Matter Haloes and Host Galaxies of MgII Absorbers at z~1

Abstract

Strong foreground absorption features from singly-ionized Magnesium (Mg II) are commonly observed in the spectra of quasars and are presumed to probe a wide range of galactic environments. To date, measurements of the average dark matter halo masses of intervening Mg II absorbers by way of large-scale cross-correlations with luminous galaxies have been limited to z<0.7. In this work we cross-correlate 21 strong (Wλ2796>0.6 °A) Mg II absorption systems detected in quasar spectra from the Sloan Digital Sky Survey Data Release 7 with ~32,000 spectroscopically confirmed galaxies at 0.7<z<1.45 from the DEEP2 galaxy redshift survey. We measure dark matter (DM) halo biases of b_G=1.44\pm0.02 and b_A=1.49\pm0.45 for the DEEP2 galaxies and Mg II absorbers, respectively, indicating that their clustering amplitudes are roughly consistent. Haloes with the bias we measure for the Mg II absorbers have a corresponding mass of 1.8(+4.2/-1.6) \times 10^12h-1M_sun, although the actual mean absorber halo mass will depend on the precise distribution of absorbers within DM haloes. This mass estimate is consistent with observations at z=0.6, suggesting that the halo masses of typical Mg II absorbers do not significantly evolve from z~1. We additionally measure the average Wλ2796>0.6 Ågas covering fraction to be f =0.5 within 60 h-1kpc around the DEEP2 galaxies, and we find an absence of coincident strong Mg II absorption beyond a projected separation of ~40 h-1kpc. Although the star-forming z>1 DEEP2 galaxies are known to exhibit ubiquitous blueshifted Mg II absorption, we find no direct evidence in our small sample linking Wλ2796>0.6 Åabsorbers to galaxies with ongoing star formation.

12 pages, 5 figures, Accepted to MNRAS

References in corpus (19)

• Ubiquitous outflows in DEEP2 spectra of star-forming galaxies at z=1.4
• The 2dF-SDSS LRG and QSO Survey: The LRG 2-Point Correlation Function and Redshift-Space Distortions
• Galaxy clustering in the NEWFIRM Medium Band Survey: the relationship between stellar mass and dark matter halo mass at 1 < z < 2
• The 2dF-SDSS LRG and QSO survey: Evolution of the Luminosity Function of Luminous Red Galaxies to z=0.6
• New perspectives on strong z=0.5 MgII absorbers: are halo-mass and equivalent width anti-correlated?
• The 2dF-SDSS LRG and QSO survey: evolution of the clustering of luminous red galaxies since z = 0.6
• Narrow associated QSO absorbers: clustering, outflows and the line-of-sight proximity effect
• The SINFONI MgII Program for Line Emitters (SIMPLE): Discovering starbursts near QSO sight-lines
• Luminosity Function Constraints on the Evolution of Massive Red Galaxies Since z~0.9
• Halo Gas and Galaxy Disk Kinematics of a Volume-Limited Sample of MgII Absorption-Selected Galaxies at z~0.1
• On the HI content, dust-to-gas ratio and nature of MgII absorbers
• The Baryon Content of Dark Matter Halos: Empirical Constraints from MgII Absorbers
• The Clustering of MgII Absorption Systems at z=0.5 and Detection of Cold Gas in Massive Halos
• The clustering of radio galaxies at z~0.55 from the 2SLAQ LRG survey
• On the Halo Occupation of Dark Baryons
• The star formation rate of CaII and damped Lyman-alpha absorbers at 0.4<z<1.3
• The MgII Cross-section of Luminous Red Galaxies
• A Kennicutt-Schmidt Law for Intervening Absorption Line Systems
• SOAR Imaging of sub-Damped Lyman-Alpha Systems at z<1

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• The Geometry of Cold, Metal-Enriched Gas Around Galaxies at $z\sim 1.2$
• Large-Scale Star Formation-Driven Outflows at 1<z<2 in the 3D-HST Survey
• MusE GAs Flow and Wind (MEGAFLOW) VI. A study of CIV and MgII absorbing gas surrounding [OII] emitting galaxies
• Observations of Mg II Absorption Near z ~ 1 Galaxies Selected From The DEEP2 Redshift Survey
• The Cross-correlation of MgII Absorption and Galaxies in BOSS
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• The Detection Rate of Associated \mgii\ Absorption Lines in Quasars Depends on Their Radio Emission