English
Related papers

Related papers: Moderate Correlation between the Accretion Disk an…

200 papers

Among the blazars detected by the Fermi satellite, we have selected the 23 blazars that in the three months of survey had an average gamma-ray luminosity above 1e48 erg/s. For 17 out of the 23 sources we found and analysed X-ray and…

High Energy Astrophysical Phenomena · Physics 2015-05-13 G. Ghisellini , F. Tavecchio , G. Ghirlanda

We have analyzed a large sample of clean blazars detected by Fermi Large Area Telescope (LAT). Using literature and calculation, we obtained intrinsic $\gamma$-ray luminosity excluding beaming effect, black hole mass, broad-line luminosity…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Dingrong Xiong , Xiong Zhang

We study the general physical properties of Fermi blazars using the Fermi fourth source catalog data (4FGL-DR2). The quasi-simultaneous multiwavelength data of Fermi blazar are fitted by using the one-zone leptonic model to obtain some…

High Energy Astrophysical Phenomena · Physics 2023-07-03 Yongyun Chen , Qiusheng Gu , Junhui Fan , Xiaoling Yu , Xiaogu Zhong , Hongyu Liu , Nan Ding , Dingrong Xiong , Xiaotong Guo

We present our latest results on the connection between accretion rate and relativistic jet power in AGN, by using a large sample which includes mostly blazars, but contains also some radio--galaxies. The jet power can be traced by…

High Energy Astrophysical Phenomena · Physics 2015-06-19 T. Sbarrato , P. Padovani , G. Ghisellini

We studied all blazars of known redshift detected by the Fermi satellite during its first three months survey. For the majority of them, pointed Swift observations ensures a good multiwavelength coverage, enabling us to to reliably…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 G. Ghisellini , F. Tavecchio , L. Foschini , G. Ghirlanda , L. Maraschi , A. Celotti

The properties of relativistic radio jets are thought to be closely connected with the properties of accretion disks in active galactic nuclei. We explore this issue using a sample of 35 blazars with very-long baseline observations, for…

Astrophysics · Physics 2009-11-10 Jian-Min Wang , Bin Luo , Luis C. Ho

The new high energy data coming mainly from the Fermi and Swift satellites and from the ground based Cerenkov telescopes are making possible to study not only the energetics of blazar jets, but also their connection to the associated…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Gabriele Ghisellini

Jet origination is one of the most important questions of AGN, yet it stays obscure. In this work, we made use of information of emission lines, spectral energy distributions (SEDs), \textit{Fermi}-LAT $\gamma$-ray emission, construct a…

High Energy Astrophysical Phenomena · Physics 2022-02-02 Hubing Xiao , Zhihao OuYang , Lixia Zhang , Liping Fu , Shaohua Zhang , Xiangtao Zeng , Junhui Fan

We have not identified for sure what is the mechanism launching, accelerating and collimating relativistic jets. The two most likely possibilities are the gravitational energy of the accreting matter or the rotational energy of a spinning…

High Energy Astrophysical Phenomena · Physics 2018-09-21 Gabriele Ghisellini

The Fermi and Swift satellites, together with ground based Cherenkov telescopes, has greatly improved our knowledge of blazars, namely Flat Spectrum Radio Quasars and BL Lac objects, since all but the most powerful emit most of their…

High Energy Astrophysical Phenomena · Physics 2015-06-17 G. Ghisellini

We study the relationship between jet power and accretion for Fermi and non-Fermi blazars, respectively. We also compare the relevant parameter between them. Our main results are as follows. (i) Fermi and non-Fermi blazars have significant…

High Energy Astrophysical Phenomena · Physics 2015-03-31 Y. Y. Chen , X. Zhang , H. J. Zhang , X. L. Yu

Theoretical models for the production of relativistic jets from active galactic nuclei predict that jet power arises from the spin and mass of the central black hole, as well as the magnetic field near the event horizon. The physical…

High Energy Astrophysical Phenomena · Physics 2015-06-23 G. Ghisellini , F. Tavecchio , L. Maraschi , A. Celotti , T. Sbarrato

The study of blazar jet has been performed for several decades via the VLBI technique, while its generation and propagation stay unclear. In the present work, we compiled a sample of 407 VLBI detected \textit{Fermi} blazars (VFBs) and…

High Energy Astrophysical Phenomena · Physics 2023-03-30 H. B. Xiao , J. T. Zhu , J. H. Fan , Z. Y. Pei , Z. J. Luo , S. H. Zhang

We study the broad emission line blazars detected in the gamma-ray band by the Large Area Telescope onboard the Fermi satellite and with the optical spectrum studied by Shaw et al. (2012, 2013). The observed broad line strength provides a…

High Energy Astrophysical Phenomena · Physics 2015-06-23 G. Ghisellini , F. Tavecchio

Most of the electromagnetic output of blazars (BL Lac objects and Flat Spectrum Radio Quasars) comes out in the gamma-ray band, making the Large Area Telescope [0.1-100 GeV] onboard the Fermi satellite and the Cherenkov telescopes crucial…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 G. Ghisellini

We discuss the relation between the power carried by relativistic jets and the nuclear power provided by accretion, for a group of blazars including FSRQs and BL Lac objects. They are characterized by good quality broad band X-ray data…

Astrophysics · Physics 2009-11-07 Laura Maraschi , Fabrizio Tavecchio

With the release of the first year Fermi catalogue, the number of blazars detected above 100 MeV lying at high redshift has been largely increased. There are 28 blazars at z>2 in the "clean" sample. All of them are Flat Spectrum Radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Ghisellini , G. Tagliaferri , L. Foschini , G. Ghirlanda , F. Tavecchio , R. Della Ceca , F. Haardt , M. Volonteri , N. Gehrels

The origin of jet launching mainly comes from two mechanisms: the BZ mechanism and the BP mechanism. However, it is in debate which one is dominating in blazars. In this work, we used a sample of 937 Fermi blazars to study the jet formation…

High Energy Astrophysical Phenomena · Physics 2024-11-19 Shangchun Xie , Zhihao Ouyang , Jingyu Wu , Hubing Xiao , Shaohua Zhang , Yongyun Chen , Zhijian Luo , Junhui Fan

The relation between accretion disc (thermal emission) and jet (non-thermal emission) in blazars is still a mystery as, typically, the beamed jet emission swamps the disc even in the ultraviolet band where disc emission peaks. In this paper…

Astrophysics · Physics 2009-11-07 V. D'Elia , P. Padovani , H. Landt

The correlation between the jet power and accretion disk luminosity is investigated and analyzed with our model for 7 samples of low luminosity active galactic nuclei (LLAGNs). The main results are: (1) the power-law correlation index…

Astrophysics of Galaxies · Physics 2016-12-14 Renzhi Su , Xiang Liu , Zhen Zhang
‹ Prev 1 2 3 10 Next ›