부산대학교 도서관

We study γ -ray luminosity functions (GLFs) and the contribution to the extragalactic diffuse γ -rays for blazars. After using a clean blazar sample in which 485 blazars are observed at both the 8.4 GHz and - GeV bands, we investigate the radio/γ -ray luminosity correlation and find out that a strong correlation exists between the radio and γ -ray luminosities using the partial correlation analysis method. Based on such a correlation, we obtain the GLF, while also considering the GLF based on studies of the X-ray luminosity function of active galactic nuclei and the GLF of the EGRET blazars. K-S tests indicate that these three kinds of GLFs are consistent with the observed data of our sample in a reasonable parameter range. Using these GLFs, we further investigate the blazar contribution to the extragalactic diffuse γ -ray background (EGRB). Our results show that (1) the contribution of blazars are ~21.3%±2.7%, ~12.9%±1.7%, and ~37.9%±4.8% of unresolved Fermi EGRB flux for the three GLFs and (2) the contribution of flat-spectrum radio quasars are ~11.2%±1.6%, ~6.9%±1.0%, and ~9.0%±1.2% of unresolved Fermi EGRB flux for the three GLFs. [ABSTRACT FROM AUTHOR]