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Quasar clustering: evidence for an increase with redshift and implications for the nature of AGNs

Fabio La Franca·Paola Andreani·Stefano Cristiani
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Abstract

The evolution of quasar clustering is investigated with a new sample of 388 quasars with 0.3 0.0 are excluded at a 0.3% probability level, to be compared with epsilon=0.8 found for galaxies. The observed clustering properties appear qualitatively consistent with a scenario of Omega=1 CDM in which a) the difference between the quasar and the galaxy clustering can be explained as a difference in the effective bias and redshift distributions, and b) the quasars, with a lifetime of t~10^8 yr, sparsely sample halos of mass greater than M_min~10^12-10^13 h^-1 M_sun. We discuss also the possibility that the observed change in the quasar clustering is due to an increase in the fraction of early-type galaxies as quasar hosts at high z.

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Fabio La Franca, Paola Andreani, Stefano Cristiani. 1997-11-06. Quasar clustering: evidence for an increase with redshift and implications for the nature of AGNs. https://doi.org/10.1086/305508

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