摘要
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.
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.
基金
supported by the National Natural Science Foundation of China (Grant Nos. 10873010 and 10733010)
the National Basic Research Program of China (Grant No. 2009CB824800)
