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Related papers: Modelling the variability of 1ES1218+30.4

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We report on VERITAS observations of the BL Lac object B2 1215+30 between 2008 and 2012. During this period, the source was detected at very high energies (VHE; E > 100 GeV) by VERITAS with a significance of $8.9\sigma$ and showed clear…

We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the…

We present very-high-energy $\gamma$-ray observations of the BL Lac object 1ES 2344+514 taken by the Very Energetic Radiation Imaging Telescope Array System (VERITAS) between 2007 and 2015. 1ES 2344+514 is detected with a statistical…

During May 2013, a gamma-ray flare from the BL Lac object 1ES 1727+502 (z=0.055) has been detected with the VERITAS Cherenkov telescopes. This detection represents the first evidence of very-high-energy (E>100 GeV) variability from this…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Matteo Cerruti

We present results of 45 hours of data taken from January to June 2011 with VERITAS above 200 GeV in the direction of B2 1215+30. The blazar was clearly detected with a constant flux of F(E>200 GeV) = (8.0 +- 0.9) \times 10^{-12} cm^{-2}…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Heike Prokoph

We present here the results of the analysis of the $\gamma$-ray blazar, 1ES 1215+303, over a 10-year period, from 2008 to 2017, measured at high energies (HE; 200 MeV $< E <$ 100 GeV) by the Fermi Large Area Telescope (LAT) and at very high…

High Energy Astrophysical Phenomena · Physics 2017-12-19 Janeth Valverde , Deirdre Horan , Giuliana Noto , Reshmi Mukherjee , Denis Bernard

Multiwavelength observations of blazars such as Mrk 421 and Mrk 501 show that they exhibit strong short time variabilities in flare-like phenomena. Based on the homogeneous synchrotron self-Compton (SSC) model and assuming that time…

Astrophysics · Physics 2009-10-31 H. Li , M. Kusunose

We report on the VERITAS discovery of very-high-energy (VHE) gamma- ray emission above 200 GeV from the high-frequency-peaked BL Lac object RXJ0648.7+1516 (GBJ0648+1516), associated with 1FGLJ0648.8+1516. The photon spectrum above 200 GeV…

We present results from multiwavelength observations of the BL Lacertae object 1ES 1741+196, including results in the very-high-energy $\gamma$-ray regime using the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The…

1ES 1218+304 is among a group of several TeV blazars that exhibit surprisingly hard energy spectra given their redshifts. The VERITAS collaboration has carried out an intensive observing campaign of 1ES 1218+304 in early 2009 to…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Asif Imran

1ES 1218+304 is a moderate-redshift (z = 0.182) high-frequency-peaked BL Lac object (HBL). Detected by both the MAGIC and VERITAS gamma-ray observatories, 1ES 1218+304 is frequently monitored by VERITAS as part of its long-term blazar…

High Energy Astrophysical Phenomena · Physics 2019-09-02 Stephan O'Brien

During moonlit nights, observations with ground-based Cherenkov telescopes at very high energies (VHE, $E>100$ GeV) are constrained since the photomultiplier tubes (PMTs) in the telescope camera are extremely sensitive to the background…

Blazars are characterized by large amplitude and fast variability, indicating that the electron distribution is rapidly changing, often on time scales shorter than the light crossing time. The emitting region is sufficiently compact to let…

Astrophysics · Physics 2009-10-31 Marco Chiaberge , Gabriele Ghisellini

Observations of the blazars 1ES 0647+250 and 1ES 0806+524 with VERITAS are reported here. These objects are among the favoured candidate extragalactic sources in the very high-energy regime due to the presence of high-energy electrons and…

Astrophysics · Physics 2019-08-13 P. Cogan

RGB J2243+203 is a blazar at an estimated redshift of greater than 0.39 that has been classified both as an intermediate-frequency-peaked BL Lac object and as a high-frequency-peaked BL Lac object. This source has been detected by VERITAS…

High Energy Astrophysical Phenomena · Physics 2019-08-13 A. U. Abeysekara

This paper presents the results of a detailed timing and spectral analysis of the TeV-detected blazar 1ES 1218+304, focused on the observations performed with the different instruments onboard the Neil Gehrels Swift Observatory in the…

Astrophysics of Galaxies · Physics 2025-04-22 B. Kapanadze , A. Gurchumelia , M. Aller

VERITAS, an array of imaging atmospheric-Cherenkov telescopes, studies blazars in the energy range between ~100 GeV and ~30 TeV. With its excellent sensitivity at these energies, and ever-deepening source exposures, VERITAS is in a position…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-13 Matthew Orr

We summarize broadband observations of the TeV-emitting blazar 1ES 1959+650, including optical R-band observations by the robotic telescopes Super-LOTIS and iTelescope, UV observations by Swift UVOT, X-ray observations by the Swift X-ray…

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