Stochastic approach to modeling the γ-ray variability of Fermi/LAT blazars

被引:0
作者
Sobolewska, M. [1 ]
Siemiginowska, A. [2 ]
Kelly, B. [3 ]
Nalewajko, K. [4 ]
机构
[1] Nicolaus Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland
[2] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA
[3] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA
[4] Stanford Univ, SLAC Natl Accelerator Lab, Kavli Inst Particle Astrophys & Cosmol, Menlo Pk, CA 94025 USA
来源
EXTRAGALACTIC JETS FROM EVERY ANGLE | 2015年 / 10卷 / 313期
关键词
black hole physics; BL Lacertae objects: general; galaxies: active; galaxies: jets; gamma rays: galaxies; EVOLUTION;
D O I
10.1017/S1743921315001805
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We studied the gamma-ray variability of 13 blazars observed with the Fermi Large Area Telescope (LAT). These blazars were among the brightest ones monitored during the first 4 years of the Fermi sky survey. We modelled their gamma-ray light curves with the Ornstein-Uhlenbeck (OU) process or mixed OU process. The power spectral density (PSD) of the OU process is a zero-centered Lorentzian function, proportional to 1/f(alpha) with a changing at a characteristic time scale, tau(0), from 0 (tau >> tau(0)) to 2 (tau << tau(0)). The PSD of the mixed OU process has in addition an intermediate part with 0 < alpha < 2 between the long and short characteristic time scales. We show that the OU model provides a good description of the Fermi/LAT light curves of three blazars in our sample. For the first time we provide constraints on the characteristic gamma-ray time scale of variability in two BL Lac sources, 3C 66A and PKS 2155-304. We find that the mixed OU process describes the light curves of the remaining 10 blazars better than the OU process. We infer that their Fermi/LAT PSD resemble power-law functions and constrain their PSD slopes.
引用
收藏
页码:21 / 26
页数:6
相关论文
共 50 条
[41]   Mid-infrared variability of γ-ray emitting blazars [J].
Anjum, Ayesha ;
Stalin, C. S. ;
Rakshit, Suvendu ;
Gudennavar, Shivappa B. ;
Durgapal, Alok .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2020, 494 (01) :764-774
[42]   Fast γ-Ray Variability in Blazars beyond Redshift 3 [J].
Li, Shang ;
Xia, Zi-Qing ;
Liang, Yun-Feng ;
Liao, Neng-Hui ;
Fan, Yi-Zhong .
ASTROPHYSICAL JOURNAL, 2018, 853 (02)
[43]   Source Count Distribution of Fermi LAT Gamma-Ray Blazars Using Novel Nonparametric Methods [J].
Yin, Xuhang ;
Zeng, Houdun .
UNIVERSE, 2024, 10 (09)
[44]   POLARIZATION AND VARIATION OF NEAR-INFRARED LIGHT FROM FERMI/LAT γ-RAY SOURCES [J].
Fujiwara, M. ;
Matsuoka, Y. ;
Ienaka, N. .
ASTRONOMICAL JOURNAL, 2012, 144 (04)
[45]   Study of the variability of blazars gamma-ray emission [J].
Sbarrato, T. ;
Foschini, L. ;
Ghisellini, G. ;
Tavecchio, F. .
ADVANCES IN SPACE RESEARCH, 2011, 48 (06) :998-1003
[46]   Long term γ-ray variability of blazars [J].
Rajput, Bhoomika ;
Stalin, C. S. ;
Rakshit, Suvendu .
ASTRONOMY & ASTROPHYSICS, 2020, 634
[47]   The sequence of Compton dominance in blazars based on data from WISE and Fermi-LAT [J].
Nalewajko, Krzysztof ;
Gupta, Maitrayee .
ASTRONOMY & ASTROPHYSICS, 2017, 606
[48]   Correlation between γ-ray and radio emissions in Fermi blazars [J].
Wu, De-Xiang ;
Fan, Jun-Hui ;
Liu, Yi ;
Yang, Jiang-He ;
Hao, Jing-Meng ;
Pei, Zhi-Yuan ;
Lin, Chao .
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN, 2014, 66 (06)
[49]   VERITAS OBSERVATIONS OF SIX BRIGHT, HARD-SPECTRUM FERMI-LAT BLAZARS [J].
Aliu, E. ;
Archambault, S. ;
Arlen, T. ;
Aune, T. ;
Beilicke, M. ;
Benbow, W. ;
Boettcher, M. ;
Bouvier, A. ;
Buckley, J. H. ;
Bugaev, V. ;
Cesarini, A. ;
Ciupik, L. ;
Collins-Hughes, E. ;
Connolly, M. P. ;
Cui, W. ;
Dickherber, R. ;
Duke, C. ;
Dumm, J. ;
Errando, M. ;
Falcone, A. ;
Federici, S. ;
Feng, Q. ;
Finley, J. P. ;
Finnegan, G. ;
Fortson, L. ;
Furniss, A. ;
Galante, N. ;
Gall, D. ;
Godambe, S. ;
Griffin, S. ;
Grube, J. ;
Gyuk, G. ;
Hanna, D. ;
Holder, J. ;
Huan, H. ;
Kaaret, P. ;
Karlsson, N. ;
Khassen, Y. ;
Kieda, D. ;
Krawczynski, H. ;
Krennrich, F. ;
Lee, K. ;
Madhavan, A. S. ;
Maier, G. ;
Majumdar, P. ;
McArthur, S. ;
McCann, A. ;
Moriarty, P. ;
Mukherjee, R. ;
Nelson, T. .
ASTROPHYSICAL JOURNAL, 2012, 759 (02)
[50]   Relation between X-Ray and γ-Ray Emissions for Fermi Blazars [J].
Li, Bijun ;
Zhang, Xiong .
JOURNAL OF ASTROPHYSICS AND ASTRONOMY, 2014, 35 (03) :345-347