The Connection between BL Lacs and FSRQs

V. D'Elia; A. Cavaliere

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arXiv · astro-ph/0101124

The Connection between BL Lacs and FSRQs

V. D'Elia·A. Cavaliere

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Abstract

We discuss the features that mark the Flat Spectrum Radio Quasars from the BL Lacertae objects. We propose that FSRQs exceeding L = 10^{46} erg/s are powered by black hole accreting at rates dm/dt = 1 - 10; their power is dominated by the disk components, thermal and BZ. Instead, sources accreting at rates 10^{-3} < dm/dt < 10^{-2} radiate in the BL Lac mode; here the power is mainly non-thermal, and is driven by the rotational energy stored in a Kerr hole which sustains L < 10^{46} erg/s in the jet frame for Gyrs. The two populations may be even linked if around the same objects dm/dt drops in time; then some negative cosmological evolution is expected for the newborn BL Lacs fed by the dying FSRQs. Further implications are discussed.

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V. D'Elia, A. Cavaliere. 2001-03-19. The Connection between BL Lacs and FSRQs. https://arxiv.org/abs/astro-ph/0101124

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