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Related papers: Blazar Flaring Rates Measured with GLAST

200 papers

Fermi-LAT observations provide continuous and regularly-sampled measurements of gamma-ray photon flux for hundreds of blazars. Many of these light curves, spanning almost 15 years, have been thoroughly examined for periodicity in multiple…

High Energy Astrophysical Phenomena · Physics 2023-09-26 Polina Novikova , Ekaterina Shishkina , Dmitry Blinov

Possible indirect detection of neutralino, through its gamma-ray annihilation product, by the forthcoming GLAST satellite from our galactic halo, M31, M87 and the dwarf galaxies Draco and Sagittarius is studied. Gamma-ray fluxes are…

Astrophysics · Physics 2009-11-10 Sebastien Peirani , Roya Mohayaee , Jose A. de Freitas Pacheco

Flaring activity from the jets of active galactic nuclei has been studied for several decades, closely related to the loading and evolution of the jet. In this work, we focus on the sub-hundred parsec jet region, well traced by non-thermal…

High Energy Astrophysical Phenomena · Physics 2026-04-07 Alina Kochocki , Emma Kun , Sam Hori

Results of a phenomenological model to estimate the GRB detection rate by the Fermi Gamma ray Space Telescope are reported. This estimate is based on the BATSE 4B GRB fluence distribution, the mean ratio of fluences measured at 100 MeV - 5…

Astrophysics · Physics 2015-05-13 Truong Le , Charles D. Dermer

Intermediate-frequency-peaked BL Lacertae objects (IBLs) are a class of blazars characterized by a spectral energy distribution (SED) with a lower-energy synchrotron peak than the majority of extragalactic sources detected by ground-based…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Juliana Vievering

Blazars are strongly variable sources that occasionally show spectacular flares visible in various energy bands. These flares are often, but not always, correlated. In a number of cases the peaks of optical flares are found to be somewhat…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Mateusz Janiak , Marek Sikora , Krzysztof Nalewajko , Rafał Moderski , Greg M. Madejski

Blazars show optical and $\gamma$-ray flux variations that are generally correlated, although there are exceptions. Here we present anomalous behaviour seen in the blazar 3C 454.3 based on an analysis of quasi-simultaneous data at optical,…

High Energy Astrophysical Phenomena · Physics 2019-04-10 Bhoomika Rajput , C. S. Stalin , S. Sahayanathan , Suvendu Rakshit , Amit Kumar Mandal

High redshift blazars are among the most powerful non-explosive sources in the Universe and play a crucial role in understanding the evolution of relativistic jets. To understand these bright objects, we performed a detailed investigation…

High Energy Astrophysical Phenomena · Physics 2024-01-29 N. Sahakyan , G. Harutyunyan , S. Gasparyan , D. Israyelyan

Jets in blazars are an excellent forum for studying acceleration at relativistic shocks using the highly-variable emission seen across the electromagnetic spectrum. Our recent work on combining multi-wavelength leptonic emission models with…

High Energy Astrophysical Phenomena · Physics 2020-01-01 Matthew G. Baring , Markus Boettcher

This paper presents light curves and the first systematic characterization of variability of the 106 objects in the Fermi Large Area Telescope (LAT) Bright AGN Sample (LBAS). Weekly light curves obtained during the first 11 months of survey…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. A. Abdo

Some pulsars have their maximum observable energy output in the gamma-ray band, offering the possibility of using these high-energy photons as probes of the particle acceleration and interaction processes in pulsar magnetospheres. After an…

Astrophysics · Physics 2009-06-23 D. J. Thompson

We present ~2000 polarimetric and ~3000 photometric observations of 15 gamma-ray bright blazars over a period of 936 days (11/10/2008 - 26/10/2012) using data from the Tuorla blazar monitoring program (KVA DIPOL) and Liverpool Telescope…

High Energy Astrophysical Phenomena · Physics 2016-09-15 H. Jermak , I. A. Steele , E. Lindfors , T. Hovatta , K. Nilsson , G. P. Lamb , C. Mundell , U. Barres de Almeida , A. Berdyugin , V. Kadenius , R. Reinthal , L. Takalo

Spectroscopic observations covering the wavelength range 3600--4600\AA are presented for a large flare on the late type M dwarf AT Mic (dM4.5e). A procedure to estimate the physical parameters of the flaring plasma has been used which…

Flare flux reflect contribution from active regions rather than the whole hemisphere of a star. Unlike the amplitude of light-curves caused by starspots, the flare detection is independent of inclination. The two valuable properties of…

Solar and Stellar Astrophysics · Physics 2026-03-04 Huiqin Yang , Shuai Liu , Yang Huang , Bowen Zhang , Jifeng Liu

Around the peaks of substantial flares, bright artifact nearly horizontal saturation streaks (B-streaks) corresponding to the brightest parts of the flare sources appear in the STEREO/EUVI 195 A images. We show that the length of such…

Solar and Stellar Astrophysics · Physics 2015-08-06 I. M. Chertok , A. V. Belov , V. V. Grechnev

Solar flares commonly have a hot onset precursor event" (HOPE), detectable from soft X-ray observations. Detecting this requires subtraction of pre-flare fluxes from the non-flaring Sun prior to the event, fitting an isothermal emission…

Solar and Stellar Astrophysics · Physics 2024-07-08 Hugh S. Hudson

The gamma-ray emission of blazar jets shows a pronounced variability and this feature provides limits to the size and to the speed of the emitting region. We study the gamma-ray variability of bright blazars using data from the first 18…

High Energy Astrophysical Phenomena · Physics 2015-05-28 T. Sbarrato , L. Foschini , G. Ghisellini , F. Tavecchio

We present a flare rate analysis of 50,130 M dwarf light curves in SDSS Stripe 82. We identified 271 flares using a customized variability index to search ~2.5 million photometric observations for flux increases in the u- and g-bands. Every…

Solar and Stellar Astrophysics · Physics 2009-07-28 A. F. Kowalski , S. L. Hawley , E. J. Hilton , A. C. Becker , A. A. West , J. J. Bochanski , B. Sesar

We conducted a comprehensive temporal and spectral study of the FSRQ PKS 0805-07 by using the broadband observations from the Fermi-LAT and Swift-XRT/UVOT instruments over the period MJD 54684-60264. The 3-day binned $\gamma$-ray light…

High Energy Astrophysical Phenomena · Physics 2024-12-13 Sikandar A. Dar , Zahir Shah , Ranjeev Misra , Naseer Iqbal

Blazars are known for their energetic multiwavelength flares from radio wavelengths to high-energy $\gamma$-rays. In this work, we study radio, optical, and $\gamma$-ray light curves of 145 bright blazars spanning up to 8~yr, to probe the…

High Energy Astrophysical Phenomena · Physics 2018-08-20 I. Liodakis , R. W. Romani , A. V. Filippenko , S. Kiehlmann , W. Max-Moerbeck , A. C. S. Readhead , W. Zheng
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