Does black hole spin play a key role in the FSRQ/BL Lac dichotomy?

Bhattacharya, Debbijoy and Sreekumar, Parameswaran and Mukhopadhyay, Banibrata and Tomar, Ishan (2016) Does black hole spin play a key role in the FSRQ/BL Lac dichotomy? In: RESEARCH IN ASTRONOMY AND ASTROPHYSICS, 16 (4).

PDF Res_Ast_Ast_16-4_54_2016.pdf - Published Version Restricted to Registered users only Download (201kB) | Request a copy

Abstract

Blazars are characterized by large intensity and spectral variations across the electromagnetic spectrum It is believed that jets emerging from them are almost aligned with the line-of-sight. The majority of identified extragalactic sources in gamma-ray catalogs of EGRET and Fermi are blazars. Observationally, blazars can be divided into two classes: flat spectrum radio quasars (FSRQs) and BL Lacs. BL Lacs usually exhibit lower gamma-ray luminosity and harder power law spectra at gamma-ray energies than FSRQs. We attempt to explain the high energy properties of FSRQs and BL Lacs from Fermi gamma-ray space telescope observations. It was argued previously that the difference in accretion rates is mainly responsible for the large mismatch in observed luminosity in gamma-ray. However, when intrinsic luminosities are derived by correcting for beaming effects, this difference in gamma-ray luminosity between the two classes is significantly reduced. In order to explain this difference in intrinsic luminosities, we propose that spin plays an important role in the luminosity distribution dichotomy of BL Lacs and FSRQs. As the outflow power of a blazar increases with increasing spin of a central black hole, we suggest that the spin plays a crucial role in making BL Lac sources low luminous and slow rotators compared to FSRQ sources.

Item Type:	Journal Article
Publication:	RESEARCH IN ASTRONOMY AND ASTROPHYSICS
Publisher:	NATL ASTRONOMICAL OBSERVATORIES, CHIN ACAD SCIENCES
Additional Information:	Copy right for this article belongs to the NATL ASTRONOMICAL OBSERVATORIES, CHIN ACAD SCIENCES, 20A DATUN RD, CHAOYANG, BEIJING, 100012, PEOPLES R CHINA
Keywords:	BL Lacertae objects: general; quasars: general; galaxies: jets; black hole physics; relativistic processes; gravitation
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	11 Jun 2016 09:18
Last Modified:	11 Jun 2016 09:18
URI:	http://eprints.iisc.ac.in/id/eprint/53913

Actions (login required)

View Item