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相关论文: Study of long-term flux and photon Index distribut…

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We have measured multi-band optical flux and colour variations for a sample of 12 low energy peaked blazars on short, day-to-month, timescales. Our sample contains six BL Lacertae objects and six flat spectrum radio quasars. These…

Optical observations of a sample of 12 $\gamma$-ray bright blazars from four optical data archives, AAVSO, SMARTS, Catalina, and Steward Observatory, are compiled to create densely sampled light curves spanning more than a decade. As a part…

高能天体物理现象 · 物理学 2021-12-15 Gopal Bhatta

Blazars exhibit stochastic flux variability across the electromagnetic spectrum, often exhibiting heavy-tailed flux distributions, commonly modeled as lognormal. However, Tavecchio et al. (2020) and Adams et al. (2022) found that the…

高能天体物理现象 · 物理学 2022-09-21 Aryeh Brill

We performed observations with the Effelsberg 100-m radio telescope to measure flux densities and polarised emission of sources selected from the "Deep X-ray Radio Blazar Survey" (DXRBS) to better define their spectral index behaviour in…

宇宙学与河外天体物理 · 物理学 2011-07-28 Franco Mantovani , Marco Bondi , Karl-Heinz Mack

Blazars are highly variable and display complex characteristics. A key characteristic is the flux probability distribution function or flux PDF whose shape depends upon the form of the underlying physical process driving variability. The BL…

高能天体物理现象 · 物理学 2020-01-09 Nachiketa Chakraborty

We present statistical analyses of a large homogenous data sample of Fermi-detected blazars thoroughly studied in order to reassess the relationship between flat-spectrum radio quasars (FSRQs) and subclasses of BL Lacertae objects (BL Lacs)…

高能天体物理现象 · 物理学 2021-08-18 E. U. Iyida , F. C. Odo , A. E. Chukwude , A. A. Ubachukwu

We present the redshift evolutions and distributions of the gamma-ray luminosity and photon spectral index of flat spectrum radio quasar (FSRQ) type blazars, using non-parametric methods to obtain the evolutions and distributions directly…

高能天体物理现象 · 物理学 2015-06-19 J. Singal , A. Ko , V. Petrosian

Characterisation of the long-term variations in the broad line region in a luminous blazar, where Comptonisation of broad-line emission within a relativistic jet is the standard scenario for production of gamma-ray emission that dominates…

高能天体物理现象 · 物理学 2020-08-04 Krzysztof Nalewajko , Alok C. Gupta , Mai Liao , Krzysztof Hryniewicz , Maitrayee Gupta , Minfeng Gu

We compiled the radio, optical, and X-ray data of blazars from the Sloan Digital Sky Survey (SDSS) database, and presented the distribution of luminosities and broad band spectral indices. The distribution of luminosities shows that the…

高能天体物理现象 · 物理学 2015-03-20 Huaizhen Li , Luoen Chen , Yunguo Jiang , Tingfeng Yi

We present long term optical and near infrared flux variability analysis of 37 blazars detected in the $\gamma$-ray band by the {\it Fermi Gamma-Ray Space Telescope}. Among them, 30 are flat spectrum radio quasars (FSRQs) and 7 are BL Lac…

高能天体物理现象 · 物理学 2020-08-28 P. Z. Safna , C. S. Stalin , Suvendu Rakshit , Blesson Mathew

Blazars, the peculiar class of active galactic nuclei (AGN), are known to show flux variations across the accessible electromagnetic spectrum. Though they have been studied extensively for their flux variability characteristics across…

We examine the long term (~10 years) gamma-ray variability of blazars observed by EGRET and Fermi and find that for six sources the average flux varied by more than an order of magnitude. For two of these sources (PKS 0208-512 and PKS…

宇宙学与河外天体物理 · 物理学 2013-03-26 Debbijoy Bhattacharya , Ranjeev Misra , A. R. Rao , P. Sreekumar

Aims. The blazars Mrk 421 and Mrk 501 have shown multiwavelength variability on all observed timescales, and have been well studied at high energies on short timescales. We aim to characterise the long-term temporal behaviour of these…

高能天体物理现象 · 物理学 2026-02-25 Gabrielle L. Taylor , Stefan J. Wagner , Alicja Wierzcholska , Michael Zacharias

We studied the long term flux distribution of Cygnus X-1 using RXTE-ASM lightcurves in two energy bands B (3-5 keV) & C (5-12.1 keV) as well as MAXI lightcurves in energy bands B (4-10 keV) & C (10-20 keV). The flux histograms were fitted…

高能天体物理现象 · 物理学 2021-04-29 Kabita Deka , Zahir Shah , Ranjeev Misra , Gazi Ameen Ahmed

We studied the optical variability of 241 BL Lacs and 83 flat-spectrum radio quasars (FSRQ) from the 4LAC catalog using data from the Tomo-e Gozen Northern Sky Transient Survey, with $\sim$ 50 epochs per blazar on average. We excluded…

We used the data from the Fermi Gamma-ray Space Telescope to characterise the {\gamma}-ray flux variability of blazars on month-like time scales. Our sample consists of 1120 blazars of which 481 are flat spectrum radio quasars (FSRQs) and…

高能天体物理现象 · 物理学 2020-02-12 Bhoomika Rajput , C. S. Stalin , Suvendu Rakshit

About twenty years of radio observations in five bands (from 4.8 to 37 GHz) of the BL Lac object GC 0109+224 (S2 0109+22, RGB J0112+227), are presented and analysed together with the optical data. Over the past ten years this blazar has…

天体物理学 · 物理学 2016-08-16 Stefano Ciprini , Gino Tosti , Harri Teräsranta , Hugh D. Aller

We study the correlations of the flux of the broad-line emission ($F_{BLR}$) with the X-ray emission flux, optical emission flux at 5500 \AA and radio emission flux at 5 GHz, respectively, for a large sample of 50 Blazars (39 flat-spectrum…

天体物理学 · 物理学 2015-05-13 T. F. Yi , G. Z. Xie

Prompted by recent discoveries of log-normal distributions in gamma-ray/X-ray temporal variabilities of gamma-ray bursts (GRBs) and blazars, we re-examine the X-ray variability of Cygnus X-1 in the hard/low state using Ginga data in 1990.…

天体物理学 · 物理学 2015-06-24 H. Negoro , S. Mineshige

We analyze X-ray light curves of the blazars Mrk 421, PKS 2155-304, and 3C 273 using observations by the Soft X-ray Telescope on board AstroSat and archival XMM-Newton data. We use light curves of length 30-90 ks each from 3-4 epochs for…

高能天体物理现象 · 物理学 2023-10-27 Joy Bhattacharyya , Ritesh Ghosh , Ritaban Chatterjee , Nabanita Das