南方基地知识库

AGNs with hard gamma-ray emission identified so far are radio-loud. III Zw 2 is a radio intermediate AGN with a relativistic jet. We study its spectral energy distribution (SED) and find that the broad band emissions are dominated by the non-thermal emissions from the jet. We model its SED through a synchrotron + inverse Compton (IC) model. The results show that the IC component of III Zw 2 peaks at a few MeV, and the flux density drops rapidly at higher energy with photon index Gamma approximate to 3.3 above 0.1 GeV. The predicted flux is slightly over the sensitivity of Fermi/LAT, but it was not included in the first Fermi/LAT AGN catalog. The reason for this may be: 1) that the IC peak is low and the spectrum is very steep above 0.1 GeV, 2) that 111 Zw 2 is in the low state during the period of the Fermi/LAT operation. We also find that III Zw 2 follows similar jet processes as those in gamma-ray AGNs, e.g., the relation between jet power and radiation power, which is called the blazar sequence. We suggest that III Zw 2 may be a young source at an earlier stage of jet activity.