Clustering of gamma-ray selected 2LAC Fermi Blazars

Abstract

We present the first measurement of the projected correlation function of 485 gamma-ray selected Blazars, divided in 175 BLLacertae (BL Lacs) and 310 Flat Spectrum Radio Quasars (FSRQs) detected in the 2-year all-sky survey by Fermi-Large Area Telescope. We find that Fermi BL Lacs and FSRQs reside in massive dark matter halos (DMHs) with logMh=13.35+0.20/-0.14 and logMh = 13.40+0.15/-0.19 Msun/h, respectively, at low (z=0.4) and high (z =1.2) redshift. In terms of clustering properties, these results suggest that BL Lacs and FSRQs are similar objects residing in the same dense environment typical of galaxy groups, despite their different spectral energy distribution, power and accretion rate. We find no difference in the typical bias and hosting halo mass between Fermi Blazars and radio-loud AGN, supporting the unifcation scheme simply equating radio-loud objects with misaligned Blazar counterparts. This similarity in terms of typical environment they preferentially live in, suggests that Blazars preferentially occupy the centre of DMHs, as already pointed out for radio-loud AGN. This implies, in light of several projects looking for the gamma-ray emission from DM annihilation in galaxy clusters, a strong contamination from Blazars to the expected signal from DM annihilation.

Accepted for publication in The Astrophysical Journal

References in corpus (11)

• The 2dF-SDSS LRG and QSO Survey: QSO clustering and the L-z degeneracy
• A new method to separate star forming from AGN galaxies at intermediate redshift: The submillijansky radio population in the VLA-COSMOS survey
• The clustering of narrow-line AGN in the local Universe
• Luminosity and redshift dependent quasar clustering
• Clustering Analyses of 300,000 Photometrically Classified Quasars--II. The Excess on Very Small Scales
• Halo masses for optically-selected and for radio-loud AGN from clustering and galaxy-galaxy lensing
• The spatial clustering of X-ray selected AGN in the XMM-COSMOS field
• The Spatial Clustering of ROSAT All-Sky Survey AGN: I. The cross-correlation function with SDSS Luminous Red Galaxies
• The clustering of radio galaxies at z~0.55 from the 2SLAQ LRG survey
• The XMM-Newton wide-field survey in the COSMOS field: V. Angular Clustering of the X-ray Point Sources
• gamma-rays from annihilating dark matter in galaxy clusters: stacking vs single source analysis

Cited by in corpus (6)

• Clustering of quasars in SDSS-IV eBOSS : study of potential systematics and bias determination
• Evidence of cross-correlation between the CMB lensing and the gamma-ray sky
• Large-scale clustering amongst Fermi blazars; evidence for axis alignments?
• High-Significance Detection of Correlation Between the Unresolved Gamma-Ray Background and the Large Scale Cosmic Structure
• Constraining blazar heating with the 2<z<3 Lyman-$\alpha$ forest
• Do BL Lac Objects and FR I radiogalaxies inhabit the same galaxy environment?