Basic properties of Gamma-ray loud blazars

نویسنده

  • K. S. Cheng
چکیده

In this paper, a method is proposed to determine the basic properties of γ-ray loud blazars, among them the central black hole mass, M , the Doppler factor, δ, the propagation angle of the γ-rays with respect to the symmetric axis of a twotemperature accretion disk, Φ, and the distance (i.e. the height above the accretion disk), d at which the γ-rays are created, for seven γ-ray loud blazars with available GeV variability timescales and in which the absorption effect of a γ-ray and the beaming effect have been taken into account. Our results indicate that, if we take the intrinsic γ-ray luminosity to be λ times the Eddington luminosity, L γ = λLEdd., the masses of the blazars are in the range of (4 ∼ 83)× 10M⊙ (λ = 1.0) or (6 ∼ 131)× 10 M⊙ (λ = 0.1), the Doppler factors (δ) lie in the range of 0.57 to 3.72 (λ = 1.0) or 0.79 to 5.33 (λ = 0.1), the angle (Φ) is in the range of 14◦ to 43◦ (λ = 1.0) or 13◦ to 39◦ (λ = 0.1), and the distance (d) is in the range of 28Rg to 411Rg (λ = 1.0) or 26Rg to 366Rg (λ = 0.1). For 3C279, the case of a uniformly-bright disk is also adopted to determine the basic parameters, which are compared with those obtained for a two-temperature disk as well as those obtained by Becker & Kafatos (1995). Our model results are independent of γ-ray emission mechanisms but they do depend on the X-ray emission mechanism of the accretion disk.

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تاریخ انتشار 1999