Abstract
For a sample of 411 type II QSOs with redshifts less then 0.3, we use the Balmer decrements to do the reddening correction of the [O III] luminosities and then derive the intrinsic [O III] luminosity function. We find that the host reddening correction of the [O III] 5007 luminosity for type II QSOs cannot be neglected. The median Balmer decrement of Hα/Hβ=4.0 corresponds to an extinction of 0.94 mag for the [O III] 5007 line, which is consistent with the result derived from the median Hβ/Hγ. Comparing the intrinsic luminosity function of type II QSOs with that of type I QSOs, we find that the upper limit of the type II QSO’s fraction in the total QSOs is 80% for type II QSOs with z < 0.3 and 8.6⩽log (L [O III]/L ⊙)⩽9.4.
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The work is supported by the National Natural Science Foundation of China (Grant Nos. 10873010 and 10733010) and the National Basic Research Program of China (Grant No. 2009CB824800).
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Bian, W., Zhang, S. Luminosity function of optically-selected type II QSOs. Sci. China Phys. Mech. Astron. 53 (Suppl 1), 191–195 (2010). https://doi.org/10.1007/s11433-010-0055-8
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DOI: https://doi.org/10.1007/s11433-010-0055-8