The multiband nonthermal emissions in radio, X-ray, and very high-energy（VHE） γ-ray bands from two distant blazars, H 2356–309 and 1ES 1218＋304, havebeen detected, and, especially from recent observations with th...The multiband nonthermal emissions in radio, X-ray, and very high-energy（VHE） γ-ray bands from two distant blazars, H 2356–309 and 1ES 1218＋304, havebeen detected, and, especially from recent observations with the Suzaku, MAGICand VERITAS telescopes, clearly reveal nonthermal power-law spectra. We study thebroadband nonthermal spectra of the two sources by using a combination of a one-zone homogeneous synchrotron self-Compton （SSC） model and an inhomogeneousconical jet model, where the new external background light （EBL） model is taken intoaccount. The results show that （1） the nonthermal emissions of the two blazars, rang-ing from X-rays to VHE γ-rays, are from the homogeneous zone whereas the emis-sions in the radio bands can be explained as the radiation from the inhomogeneousconical jet; （2） a strict lower-limit EBL model can be used to explain their observedspectra well.展开更多
The origin of ultra high energy cosmic rays (UHECRs) is still an open question in astroparticle physics. TeV blazars are a small group of active galactic nuclei (AGNs). They all have been observed in TeV gamma ray ban...The origin of ultra high energy cosmic rays (UHECRs) is still an open question in astroparticle physics. TeV blazars are a small group of active galactic nuclei (AGNs). They all have been observed in TeV gamma ray band, and show violent variabilities in flux at all wavelengths. So it is believed that they have abilities to produce UHECRs. To judge whether the TeV blazars can be the candidates of the origin of UHECRs, we collect the information of emission region of 38 TeV blazars, and estimate the maximum energy that the charged particle can be accelerated there. The results show that TeV blazars have abilities to accelerate cosmic rays to the energy above 1018?eV, some even higher than 1020?eV, and they may be the sources of UHECRs.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 10778702 and 10803005)the 973 Program (2009CB824800)Yunnan Province under grant 2009 OC
文摘The multiband nonthermal emissions in radio, X-ray, and very high-energy（VHE） γ-ray bands from two distant blazars, H 2356–309 and 1ES 1218＋304, havebeen detected, and, especially from recent observations with the Suzaku, MAGICand VERITAS telescopes, clearly reveal nonthermal power-law spectra. We study thebroadband nonthermal spectra of the two sources by using a combination of a one-zone homogeneous synchrotron self-Compton （SSC） model and an inhomogeneousconical jet model, where the new external background light （EBL） model is taken intoaccount. The results show that （1） the nonthermal emissions of the two blazars, rang-ing from X-rays to VHE γ-rays, are from the homogeneous zone whereas the emis-sions in the radio bands can be explained as the radiation from the inhomogeneousconical jet; （2） a strict lower-limit EBL model can be used to explain their observedspectra well.
文摘The origin of ultra high energy cosmic rays (UHECRs) is still an open question in astroparticle physics. TeV blazars are a small group of active galactic nuclei (AGNs). They all have been observed in TeV gamma ray band, and show violent variabilities in flux at all wavelengths. So it is believed that they have abilities to produce UHECRs. To judge whether the TeV blazars can be the candidates of the origin of UHECRs, we collect the information of emission region of 38 TeV blazars, and estimate the maximum energy that the charged particle can be accelerated there. The results show that TeV blazars have abilities to accelerate cosmic rays to the energy above 1018?eV, some even higher than 1020?eV, and they may be the sources of UHECRs.
