The evolution of the clustering of QSOs
نویسندگان
چکیده
The evolution of QSO clustering is investigated with a new sample of 388 QSOs with 0.3 < z ≤ 2.2, B ≤ 20.5 and MB < −23. Evidence is found for an increase of the clustering amplitude with increasing redshift. These measurements allow to further distinguish among the various physical scenarios proposed to interpret the QSO phenomenon. A single population model is inconsistent with the observations. The general properties of the QSO population would arise naturally if quasars are short-lived events connected to a characteristic halo mass ∼ 5 · 10 M .
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