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Title: IMPLICATIONS FOR THE BLAZAR SEQUENCE AND INVERSE COMPTON MODELS FROM FERMI BRIGHT BLAZARS

Abstract

In this paper, we use the quasi-simultaneous spectra of Fermi bright blazars and Fermi-detected narrow-line Seyfert 1 (NLS1) to study the blazar sequence and inverse Compton models. (1) The synchrotron peak luminosities (L{sub s}) significantly correlate inversely with the synchrotron peak frequencies ({nu}{sub s}), L{sub s} {proportional_to}{nu}{sup -0.44{+-}0.11}{sub s}, which is consistent with the blazar sequence. In addition to the correlation, there are some blazars showing low {nu}{sub s} and low L{sub s} . To study the relation between these low-{nu}{sub s}-low-L{sub s} blazars and the blazar sequence, we present correlations of the parameter L{sub s} {nu}{sup 1/4}{sub s} with the ratio of Compton to synchrotron peak frequencies (r{sub Cs} {identical_to} {nu}{sub C}/{nu}{sub s}) and with the ratio of Compton to synchrotron luminosities (CD {identical_to} L{sub C} /L{sub s}). The results indicate that both correlations are significant with a Pearson's probability for a null correlation of p = 0.0218 and p = 0.0286, respectively. This does not support the idea that the low-{nu}{sub s}-low-L{sub s} blazars are sources with less beaming. Another possibility, as suggested by Ghisellini and Tavecchio, is that these blazars have relatively lower black hole masses. To test this, we collect the black hole masses of 30more » blazars from archives and find that the black hole mass correlates with the parameter L{sub s} {nu}{sup 0.44}{sub s} (p = 0.0344). Therefore, the black hole masses of low-{nu}{sub s}-low-L{sub s} blazars are statistically small. The NLS1s are thought to have lower black hole masses. We find that the four NLS1s detected by Fermi have low {nu}{sub s} and low L{sub s} . This supports the above result. (2) The ratio r{sub Cs} correlates with CD significantly (p = 0.00375). The external Compton model can naturally explain this correlation, while the synchrotron self-Compton model cannot. This agrees with the findings of many authors that the EC process dominates the gamma-ray emission of flat spectrum radio quasars.« less

Authors:
;  [1]
  1. National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 (China)
Publication Date:
OSTI Identifier:
21578397
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal
Additional Journal Information:
Journal Volume: 735; Journal Issue: 2; Other Information: DOI: 10.1088/0004-637X/735/2/108; Journal ID: ISSN 0004-637X
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BL LACERTAE OBJECTS; BLACK HOLES; CORRELATIONS; EMISSION; GALAXIES; GAMMA RADIATION; LUMINOSITY; MASS; QUASARS; COSMIC RADIO SOURCES; ELECTROMAGNETIC RADIATION; IONIZING RADIATIONS; OPTICAL PROPERTIES; PHYSICAL PROPERTIES; RADIATIONS

Citation Formats

Chen Liang, and Bai, J. M., E-mail: chenliangew@hotmail.com, E-mail: baijinming@ynao.ac.cn. IMPLICATIONS FOR THE BLAZAR SEQUENCE AND INVERSE COMPTON MODELS FROM FERMI BRIGHT BLAZARS. United States: N. p., 2011. Web. doi:10.1088/0004-637X/735/2/108.
Chen Liang, & Bai, J. M., E-mail: chenliangew@hotmail.com, E-mail: baijinming@ynao.ac.cn. IMPLICATIONS FOR THE BLAZAR SEQUENCE AND INVERSE COMPTON MODELS FROM FERMI BRIGHT BLAZARS. United States. doi:10.1088/0004-637X/735/2/108.
Chen Liang, and Bai, J. M., E-mail: chenliangew@hotmail.com, E-mail: baijinming@ynao.ac.cn. Sun . "IMPLICATIONS FOR THE BLAZAR SEQUENCE AND INVERSE COMPTON MODELS FROM FERMI BRIGHT BLAZARS". United States. doi:10.1088/0004-637X/735/2/108.
@article{osti_21578397,
title = {IMPLICATIONS FOR THE BLAZAR SEQUENCE AND INVERSE COMPTON MODELS FROM FERMI BRIGHT BLAZARS},
author = {Chen Liang and Bai, J. M., E-mail: chenliangew@hotmail.com, E-mail: baijinming@ynao.ac.cn},
abstractNote = {In this paper, we use the quasi-simultaneous spectra of Fermi bright blazars and Fermi-detected narrow-line Seyfert 1 (NLS1) to study the blazar sequence and inverse Compton models. (1) The synchrotron peak luminosities (L{sub s}) significantly correlate inversely with the synchrotron peak frequencies ({nu}{sub s}), L{sub s} {proportional_to}{nu}{sup -0.44{+-}0.11}{sub s}, which is consistent with the blazar sequence. In addition to the correlation, there are some blazars showing low {nu}{sub s} and low L{sub s} . To study the relation between these low-{nu}{sub s}-low-L{sub s} blazars and the blazar sequence, we present correlations of the parameter L{sub s} {nu}{sup 1/4}{sub s} with the ratio of Compton to synchrotron peak frequencies (r{sub Cs} {identical_to} {nu}{sub C}/{nu}{sub s}) and with the ratio of Compton to synchrotron luminosities (CD {identical_to} L{sub C} /L{sub s}). The results indicate that both correlations are significant with a Pearson's probability for a null correlation of p = 0.0218 and p = 0.0286, respectively. This does not support the idea that the low-{nu}{sub s}-low-L{sub s} blazars are sources with less beaming. Another possibility, as suggested by Ghisellini and Tavecchio, is that these blazars have relatively lower black hole masses. To test this, we collect the black hole masses of 30 blazars from archives and find that the black hole mass correlates with the parameter L{sub s} {nu}{sup 0.44}{sub s} (p = 0.0344). Therefore, the black hole masses of low-{nu}{sub s}-low-L{sub s} blazars are statistically small. The NLS1s are thought to have lower black hole masses. We find that the four NLS1s detected by Fermi have low {nu}{sub s} and low L{sub s} . This supports the above result. (2) The ratio r{sub Cs} correlates with CD significantly (p = 0.00375). The external Compton model can naturally explain this correlation, while the synchrotron self-Compton model cannot. This agrees with the findings of many authors that the EC process dominates the gamma-ray emission of flat spectrum radio quasars.},
doi = {10.1088/0004-637X/735/2/108},
journal = {Astrophysical Journal},
issn = {0004-637X},
number = 2,
volume = 735,
place = {United States},
year = {2011},
month = {7}
}