ner_tags: O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O O O O O O O O O O O O B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O O O O O O B-Survey O B-Citation I-Citation I-Citation I-Citation I-Citation O O O O O O O O O O O O O O O O O O O O B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O O O O O O O B-Citation I-Citation I-Citation I-Citation O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Survey O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Tag I-Tag I-Tag I-Tag I-Tag I-Tag I-Tag O O O O O O O O O O O B-Wavelength O O O O B-CelestialRegion I-CelestialRegion B-Citation I-Citation I-Citation I-Citation O B-Citation O O O O O O O O O O O O O O O O B-Survey O O O O O O O O O O O O O O O O O O O O O O O O O B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O O O O O O B-CelestialRegion I-CelestialRegion O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Survey O O O O O O O O O B-Citation I-Citation I-Citation I-Citation O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B-Survey O O O O O O O O O O O O O O O O O O O B-Citation I-Citation I-Citation I-Citation I-Citation I-Citation O B-Survey B-Citation I-Citation I-Citation I-Citation O O O O O O O B-Survey O O B-Citation I-Citation I-Citation I-Citation O O O O O O O O O O O O O O O O O O O O
tokens: spectral template characterized by . Figure 7 shows the photometric completeness as a function of the redshift and apparent -band magnitude. Although the derived completeness is generally higher for brighter -band magnitudes as expected, the opposite tendency is seen at . This is due to the luminosity dependence of the quasar spectrum, which makes the completeness higher for lower-luminosity quasars (see Section 2.3 ). The estimated completeness at is generally higher than that estimated by Ikeda et al. ( 2011 ), which is also due to the luminosity dependence of quasar spectra, since Ikeda et al. ( 2011 ) used a composite spectrum of bright SDSS-selected quasars (Vanden Berk et al. 2001 ) for the completeness estimate. However, at , the estimated completeness in this work is lower than that estimated by Ikeda et al. ( 2012 ). This is because the new extinction model (Inoue et al. 2014 ) makes the completeness lower especially at , whose effect has a stronger impact on the completeness estimate than the effect of the luminosity dependence of the quasar spectrum. Figure 7. Photometric completeness for COSMOS quasars at (left) and at (right). Red, green, blue, purple, and cyan lines denote the estimated completeness for quasars with , respectively. 4. DISCUSSION 4.1. The QLF at <inline-formula> <tex-math> </tex-math> <inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="apjaa4497ieqn184.gif"></inline-graphic> </inline-formula> Based on the revised completeness for the previous quasar survey through optical color selection at the COSMOS field (Ikeda et al. 2011 , 2012 ), we revisit the QLF at . First we compute the effective comoving volume of the COSMOS quasar survey aswhere (1.64 deg 2 ) is the solid angle of the survey and is the photometric completeness studied in Section 3.2 . In Ikeda et al. ( 2011 ), eight spectroscopically confirmed quasars in the COSMOS field are used to derive the QLF at . Taking into account the possibility that some of the photometric quasar candidates without spectra could also be quasars (which is estimated based on the success rate of the spectroscopic run), we statistically adopt the number of quasars in the COSMOS survey at as follows: 4.67 for and 6.06 for (Ikeda et al. 2011 ). By using these corrected numbers of quasars and the effective comoving volume, we calculate the space density of quasars and their standard deviation as where and is the corrected number of quasars. The calculated space density of quasars and their standard deviation are Mpc −3 mag −1 for and Mpc −3 mag −1 for , respectively. The corrected number and calculated space density of quasars in COSMOS are shown in Table 2 , and the obtained QLF is plotted in Figure 8 with the results of Ikeda et al. ( 2011 ) and SDSS (Richards et al. 2006 ). Although the redshift range of the SDSS data ( Richards et al. 2006 ) is slightly different from our study (), we apply the weighted least-squares fit to the space density of quasars