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Title: DISCERNING THE GAMMA-RAY-EMITTING REGION IN THE FLAT SPECTRUM RADIO QUASARS

Journal Article · · Astrophysical Journal, Supplement Series
 [1]; ;  [2]
  1. Department of Physics, Yunnan Normal University, Kunming, 650092 (China)
  2. Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China)

A model-dependent method is proposed to determine the location of the γ -ray-emitting region for a given flat spectrum radio quasar (FSRQ). In the model, the extra-relativistic electrons are injected at the base of the jet and non-thermal photons are produced by both synchrotron radiation and inverse-Compton (IC) scattering in the energy dissipation region. The target photons dominating IC scattering originate from both synchrotron photons and external ambient photon fields, and the energy density of external radiation field is a function of the distance between the position of the dissipation region and a central supermassive black hole, and their spectra are seen in the comoving frame. Moreover, the energy dissipation region could be determined by the model parameter through reproducing the γ -ray spectra. Such a model is applied to reproduce the quasi-simultaneous multi-wavelength observed data for 36 FSRQs. In order to define the width of the broad-line region (BLR) shell and dusty molecular torus (MT) shell, a simple numerical constraint is used to determine the outer boundary of the BLR and dusty MT. Our results show that (1) the γ -ray-emitting regions are located at the range from 0.1 to 10 pc; (2) the γ -ray-emitting regions are located outside the BLRs and within the dusty molecular tori; and (3) the γ -ray-emitting regions are located closer to the dusty MT ranges than the BLRs. Therefore, it may be concluded that direct evidence for the far site scenario could be obtained on the basis of the model results.

OSTI ID:
22661389
Journal Information:
Astrophysical Journal, Supplement Series, Vol. 228, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0067-0049
Country of Publication:
United States
Language:
English