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Related papers: Recent Results from VERITAS AGN Observations

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The H.E.S.S. Galactic plane scan has revealed a large population of Galactic very high energy (VHE; E > 100 GeV) emitters. The majority of the galactic sources are extended and can typically be associated with pulsar wind nebulae (35%) and…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Karlen Shahinyan

Active galactic nuclei (AGN) are a promising source for high-energy astrophysical neutrinos (HEANs). By the end of 2022, the Vera C. Rubin Observatory (VRO) will begin to observe $\gtrsim10$ million AGN with a regular and high cadence.…

High Energy Astrophysical Phenomena · Physics 2022-07-13 Cyril Creque-Sarbinowski , Marc Kamionkowski , Bei Zhou

During the 2007/2008 season, VERITAS was used for observations at E>200 GeV of several extragalactic non-blazar objects such as galaxy clusters, starburst and interacting galaxies, dwarf galaxies, and nearby galaxies. In these proceedings,…

Astrophysics · Physics 2019-08-13 C. M. Hui

With 8 hours of observations, VERITAS confirms the detection of two very high energy gamma-ray sources. The gamma-ray binary LS 5039 is detected with a statistical significance of $8.8\sigma$. The measured flux above 1 TeV is $(2.5 \pm 0.4)…

Since the commissioning of the array in Spring 2007, the VERITAS array (sensitive in the 0.1-50 TeV energy range) has acquired over 300 hours of observations investigating the TeV emission from X-ray binary star systems, in particular…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Andrew W. Smith

The VERITAS collaboration has approved long-term observations on several distant, hard-spectrum blazars. We present first results from VERITAS long-term observations of 1ES1218+304, 1ES0229+200, and 1ES0414+009. Gamma-ray observations of…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Arun S. Madhavan

Many authors have predicted very-high-energy (VHE; E > 100 GeV) emission from gamma-ray bursts (GRBs) both during the prompt phase and during the multi-component afterglow. To date, however, there has been no definitive detection of such…

Astrophysics · Physics 2019-08-13 D. Horan

Gamma-ray observations of the Galactic Center (GC) region provide some of the most sensitive measurements of annihilation signals from dark matter in the GeV-TeV mass range. We present the first results from 178 hours of VERITAS…

High Energy Astrophysical Phenomena · Physics 2023-09-25 James L Ryan

The F-GAMMA-project is the coordinated effort of several observatories to understand the AGN phenomenon and specifically blazars via multi-frequency monitoring in collaboration with the {\sl Fermi}-GST satellite since January 2007. The core…

VERITAS is a new atmospheric Cherenkov imaging telescope array to detect very high energy gamma rays above 100 GeV. The array is located in southern Arizona, USA, at an altitude of 1268m above sea level. The array consists of four 12-m…

Astrophysics · Physics 2007-10-01 VERITAS Collaboration , T. Nagai , R. McKay , G. Sleege , D. Petry

The four-year X-ray all-sky survey (eRASS) of the eROSITA telescope aboard the Spektrum-Roentgen-Gamma satellite will detect ~3 million active galactic nuclei (AGN) with a median redshift of z~1 and a typical luminosity of L_(0.5-2.0 keV) ~…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-29 Alexander Kolodzig , Marat Gilfanov , Gert Hütsi , Rashid Sunyaev

Data obtained in the very high energy gamma-ray band with the new generation of imaging telescopes, in particular through the galactic plane survey undertaken by H.E.S.S., low threshold observations with MAGIC and more recently by operation…

Astrophysics · Physics 2009-11-13 Arache Djannati-Atai

We present the results of our search for highly variable active galactic nuclei (AGNs) the X-ray flux from which changed by more than an order of magnitude during the SRG/eROSITA all-sky survey. Using the eROSITA data obtained in the period…

High Energy Astrophysical Phenomena · Physics 2023-09-21 Pavel Medvedev , Marat Gilfanov , Sergey Sazonov , Rashid Sunyaev , Georgii Khorunzhev

Accurate distances to celestial objects are key to establishing the age and energy density of the Universe and the nature of dark energy. A distance measure using active galactic nuclei (AGN) has been sought for more than forty years, as…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-05 D. Watson , K. D. Denney , M. Vestergaard , T. M. Davis

The Galactic center is an interesting region for high-energy (0.1-100 GeV) and very-high-energy (E > 100 GeV) gamma-ray observations. Potential sources of GeV/TeV gamma-ray emission have been suggested, e.g., the accretion of matter onto…

High Energy Astrophysical Phenomena · Physics 2015-05-27 The VERITAS Collaboration

The VERITAS gamma-ray observatory, situated in southern Arizona, is an array of four 12m diameter imaging Cherenkov telescopes, each with a 499-pixel photomultiplier-tube camera. The instrument is designed to detect astrophysical gamma rays…

Astrophysics · Physics 2019-08-13 A. Weinstein

High-energy photons are a powerful probe for astrophysics and for fundamental physics under extreme conditions. During the recent years, our knowledge of the most violent phenomena in the universe has impressively progressed thanks to the…

High Energy Astrophysical Phenomena · Physics 2015-05-28 Alessandro De Angelis

Radio galaxies are the only non-blazar extragalactic objects detected in the VHE (E >100 GeV) band. These objects enable the investigation of the main substructures of the AGN, in particular the core, the jet and its interaction with the…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Nicola Galante

As a critical part of the Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry (TANAMI) program, in November 2007 the Australia Telescope Compact Array (ATCA) started monitoring the radio spectra of a sample of…

High Energy Astrophysical Phenomena · Physics 2012-05-14 J. Stevens , P. G. Edwards , R. Ojha , M. Kadler , F. Hungwe , M. Dutka , S. Tingay , J. P. Macquart , A. Moin , J. Lovell , J. Blanchard

Pierre Auger collaboration have recently put forward the hypothesis that the arrival directions of the highest energy cosmic rays correlate with the subset of local active galactic nuclei (AGN). We perform a blind test of AGN hypothesis…

High Energy Astrophysical Phenomena · Physics 2017-08-23 G. I. Rubtsov , I. I. Tkachev , A. D. Dolgov
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