Large Scale Structure at z=1.2 Outlined by MgII Absorbers

Abstract

The largest known structure in the high redshift universe is mapped by at least 18 quasars and spans ~5 deg x 2.5 deg on the sky, with a quasar spatial overdensity of 6-10 times above the mean. This large quasar group provides an extraordinary laboratory ~100 x 200 x 200 h^-3 comoving Mpc^3 in size (q0=0.5, Lambda=0, H0=100h km/s/Mpc) covering 1.20<z<1.39 in redshift. One approach to establish how LQGs relate to mass (galaxy) enhancements is to probe their gas content and distribution via background quasars. We have found the large quasar group to be associated with 11 MgII absorption systems at 1.2<z<1.4; 0.02%--2.05% of simulations with random MgII redshifts match or exceed this number in that redshift interval, depending on the normalization method used. The minimal spanning tree test also supports the existence of a structure of MgII absorbers coincident with the LQG, and additionally indicates a foreground structure populated by MgII absorbers and quasars at z~0.8. Finally, we find a tendency for MgII absorbers in general to correlate with field quasars (i.e. quasars both inside and outside of the LQG) at a projected scale length on the sky of 9/h Mpc and a velocity difference |Delta v|=3000 to 4500 km/s. While the correlation is on a scale consistent with observed galaxy-AGN distributions, the nonzero velocity offset could be due to the "periphery effect", in which quasars tend to populate the outskirts of clusters of galaxies and metal absorption systems, or to peculiar velocity effects.

56 pages with 8 encapulated Postscript files, 6 JPEG files, with clarified graphics and statistics, aastex Latex, accepted by ApJ

References in corpus (8)

• The Rest Frame Optical Spectra of Lyman Break Galaxies: Star Formation, Extinction, Abundances, and Kinematics
• The Effects of Photoionization on Galaxy Formation - I: Model and Results at z=0
• Galaxy Clusters in Hubble Volume Simulations: Cosmological Constraints from Sky Survey Populations
• Are high-redshift DLA galxies Lyman-break galaxies?
• A Pair of Compact Red Galaxies at Redshift 2.38, Immersed in a 100 kpc Scale Ly-alpha Nebula
• NICMOS imaging search for damped Lya galaxies
• Discovery of the Galaxy Proximity Effect and Implications for Measurements of the Ionizing Background Radiation at Low Redshifts
• The Clustering of AGN and Galaxies at Intermediate Redshift

Cited by in corpus (17)

• A structure in the early universe at z ~ 1.3 that exceeds the homogeneity scale of the R-W concordance cosmology
• New perspectives on strong z=0.5 MgII absorbers: are halo-mass and equivalent width anti-correlated?
• The environmental dependence of radio-loud AGN activity and star formation in the 2dFGRS
• A giant ring-like structure at 0.78<z<0.86 displayed by GRBs
• Galaxy Clusters in the Line of Sight to Background Quasars: I. Survey Design and Incidence of MgII Absorbers at Cluster Redshifts
• Distinct Abundance Patterns in Multiple Damped Ly-alpha Galaxies: Evidence for Truncated Star Formation?
• A Giant Arc on the Sky
• Two close Large Quasar Groups of size ~ 350 Mpc at z ~ 1.2
• An excess of damped Lyman alpha galaxies near QSOs
• Two 100 Mpc-scale structures in the 3-D distribution of radio galaxies and their implications
• Tracing high redshift cosmic web with quasar systems
• Intervening Mg II absorption systems from the SDSS DR12 quasar spectra
• 200 Mpc Sized Structure in the 2dF QSO Redshift Survey
• Detection of 20-30 Mpc-scale Galaxy Structures Embedded in 100 Mpc-scale Structures of Quasars and MgII Absorbers at z~0.8 and z~1.2
• The Clowes-Campusano Large Quasar Group Survey: I. GALEX selected sample of LBGs at z$\sim$1
• Secular Evolution of Spiral Galaxies
• Low-Metallicity Gas Clouds in a Galaxy Proto-Cluster at Redshift 2.38