Related papers: Variability Study of Extreme Blazars with VERITAS

VERITAS Discovery of Variability in the VHE Gamma-Ray Emission of 1ES 1218+304

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

Highlight Talk: Recent Results from VERITAS

VERITAS is a state-of-the-art ground-based gamma-ray observatory that operates in the very high-energy (VHE) region of 100 GeV to 50 TeV. The observatory consists of an array of four 12m-diameter imaging atmospheric Cherenkov telescopes…

High Energy Astrophysical Phenomena · Physics 2009-12-31 R. A. Ong , V. A. Acciari , T. Arlen , T. Aune , M. Beilicke , W. Benbow , D. Boltuch , S. M. Bradbury , J. H. Buckley , V. Bugaev , K. Byrum , A. Cannon , A. Cesarini , L. Ciupik , Y. C. Chow , P. Cogan , W. Cui , C. Duke , S. J. Fegan , J. P. Finley , G. Finnegan , P. Fortin , L. Fortson , A. Furniss , N. Galante , D. Gall , G. H. Gillanders , S. Godambe , J. Grube , R. Guenette , G. Gyuk , D. Hanna , J. Holder , D. Horan , C. M. Hui , T. B. Humensky , A. Imran , P. Kaaret , N. Karlsson , M. Kertzman , D. Kieda , A. Konopelko , H. Krawczynski , F. Krennrich , M. J. Lang , G. Maier , S. McArthur , A. McCann , M. McCutcheon , J. Millis , P. Moriarty , A. N. Otte , D. Pandel , J. S. Perkins , A. Pichel , M. Pohl , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , E. Roache , H. J. Rose , M. Schroedter , G. H. Sembroski , A. W. Smith , D. Steele , S. P. Swordy , M. Theiling , S. Thibadeau , J. A. Toner , A. Varlotta , V. V. Vassiliev , S. Vincent , R. G. Wagner , S. P. Wakely , J. E. Ward , T. C. Weekes , A. Weinstein , D. A. Williams , S. Wissel , M. Wood , B. Zitzer

Long term observations of B2 1215+30 with VERITAS

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…

High Energy Astrophysical Phenomena · Physics 2015-06-17 VERITAS collaboration , E. Aliu , S. Archambault , T. Arlen , T. Aune , M. Beilicke , W. Benbow , R. Bird , A. Bouvier , J. H. Buckley , V. Bugaev , A. Cesarini , L. Ciupik , M. P. Connolly , W. Cui , J. Dumm , M. Errando , A. Falcone , S. Federici , Q. Feng , J. P. Finley , P. Fortin , L. Fortson , A. Furniss , N. Galante , L. Gérard , G. H. Gillanders , S. Griffin , J. Grube , G. Gyuk , D. Hanna , J. Holder , G. Hughes , T. B. Humensky , P. Kaaret , M. Kertzman , Y. Khassen , D. Kieda , H. Krawczynski , F. Krennrich , M. J. Lang , A. S Madhavan , G. Maier , P. Majumdar , S. McArthur , A. McCann , P. Moriarty , R. Mukherjee , D. Nieto , A. O'Faoláin de Bhróithe , R. A. Ong , M. Orr , A. N. Otte , N. Park , J. S. Perkins , M. Pohl , A. Popkow , H. Prokoph , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , G. T. Richards , E. Roache , D. B. Saxon , G. H. Sembroski , C. Skole , A. W. Smith , M. Soares-Furtado , D. Staszak , I. Telezhinsky , G. Tešić , M. Theiling , A. Varlotta , V. V. Vassiliev , S. Vincent , S. P. Wakely , T. C. Weekes , A. Weinstein , R. Welsing , D. A. Williams , B. Zitzer , M. Böttcher , M. Fumagalli , J. Jadhav

Discovery of Very High-Energy Gamma-Ray Radiation from the BL Lac 1ES 0806+524

The high-frequency-peaked BL-Lacertae object \objectname{1ES 0806+524}, at redshift z=0.138, was observed in the very-high-energy (VHE) gamma-ray regime by VERITAS between November 2006 and April 2008. These data encompass the two-, and…

Astrophysics · Physics 2015-05-13 VERITAS Collaboration , V. Acciari , E. Aliu , T. Arlen , M. Bautista , M. Beilicke , W. Benbow , M. Böttcher , S. M. Bradbury , J. H. Buckley , V. Bugaev , Y. Butt , K. Byrum , A. Cannon , O. Celik , A. Cesarini , Y. C. Chow , L. Ciupik , P. Cogan , P. Colin , W. Cui , R. Dickherber , C. Duke , T. Ergin , A. Falcone , S. J. Fegan , J. P. Finley , G. Finnegan , P. Fortin , L. Fortson , A. Furniss , D. Gall , K. Gibbs , G. H. Gillanders , J. Grube , R. Guenette , G. Gyuk , D. Hanna , E. Hays , J. Holder , D. Horan , C. M. Hui , T. B. Humensky , A. Imran , P. Kaaret , N. Karlsson , M. Kertzman , D. Kieda , J. Kildea , A. Konopelko , H. Krawczynski , F. Krennrich , M. J. Lang , S. LeBohec , G. Maier , A. McCann , M. McCutcheon , J. Millis , P. Moriarty , R. Mukherjee , T. Nagai , R. A. Ong , A. N. Otte , D. Pandel , J. S. Perkins , D. Petry , M. Pohl , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , E. Roache , J. Rose , M. Schroedter , G. H. Sembroski , A. W. Smith , D. Steele , S. P. Swordy , M. Theiling , J. A. Toner , L. Valcarcel , A. Varlotta , V. V. Vassiliev , R. G. Wagner , S. P. Wakely , J. E. Ward , T. C. Weekes , A. Weinstein , R. J. White , D. A. Williams , S. Wissel , M. Wood , B. Zitzer

Study of the long-term Very High Energy emission of the blazars 1ES 1215+3031 and VER J0521+211 with the HAWC gamma-ray observatory

Blazars are the most abundant type of extragalactic gamma-ray source, usually presenting high variability across the electromagnetic spectrum. Their Very High Energy (VHE, above 0.1 TeV) emission has been studied in detail using Air…

High Energy Astrophysical Phenomena · Physics 2023-10-05 Fernando Ureña-Mena , Alberto Carramiñana , Anna Lia Longinotti , Daniel Rosa-González , HAWC Collaboration

Recent results from the VERITAS multimessenger program

VERITAS, an array of atmospheric-Cherenkov telescopes sensitive to gamma rays in the very-high-energy range (VHE, E > 100 GeV), carries out an extensive multimessenger program focused on the search for electromagnetic counterparts to…

High Energy Astrophysical Phenomena · Physics 2019-09-12 Marcos Santander

HESS J1943+213: An Extreme Blazar Shining Through The Galactic Plane

HESS J1943+213 is a very-high-energy (VHE; $>$100 GeV) $\gamma$-ray source in the direction of the Galactic Plane. Studies exploring the classification of the source are converging towards its identification as an extreme synchrotron BL Lac…

High Energy Astrophysical Phenomena · Physics 2018-08-29 The VERITAS Collaboration , A. Archer , W. Benbow , R. Bird , R. Brose , M. Buchovecky , V. Bugaev , W. Cui , M. K. Daniel , A. Falcone , Q. Feng , J. P. Finley , A. Flinders , L. Fortson , A. Furniss , G. H. Gillanders , M. Hütten , D. Hanna , O. Hervet , J. Holder , G. Hughes , T. B. Humensky , C. A. Johnson , P. Kaaret , P. Kar , N. Kelley-Hoskins , D. Kieda , M. Krause , F. Krennrich , S. Kumar , M. J. Lang , T. T. Y. Lin , S. McArthur , P. Moriarty , R. Mukherjee , D. Nieto , S. O'Brien , R. A. Ong , A. N. Otte , N. Park , A. Petrashyk , M. Pohl , A. Popkow , E. Pueschel , J. Quinn , K. Ragan , P. T. Reynolds , G. T. Richards , E. Roache , C. Rulten , I. Sadeh , G. H. Sembroski , K. Shahinyan , J. Tyler , S. P. Wakely , O. M. Weiner , A. Weinstein , R. M. Wells , P. Wilcox , A. Wilhelm , D. A. Williams , W. F. Brisken , P. Pontrelli

VERITAS Discovery of Very High-Energy Gamma-Ray Emission from RGB J2243+203

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

Recent observations of PKS 2155-304 with MAGIC and LST-1 in a multi-wavelength context

PKS 2155-304 is a well-known high-frequency peaked BL Lac (HBL) at redshift z=0.116, which has been extensively studied across the electromagnetic spectrum due to its rapid and large-amplitude variability. Several violent outbursts in…

High Energy Astrophysical Phenomena · Physics 2025-10-08 Lisa Nikolić , Gaia Verna , Marina Manganaro , Giacomo Bonnoli , Ivan Agudo , Giuseppe Silvestri , Davide Cerasole , Francesco Schiavone , Franjo Podobnik , Jorge Otero-Santos

VERITAS Observations of the Unidentified Point Source HESS J1943+213

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

A Three-Year Multi-Wavelength Study of the Very High Energy Gamma-ray Blazar 1ES 0229+200

The high-frequency-peaked BL Lacertae object 1ES 0229+200 is a relatively distant (z = 0.1396), hard-spectrum (Gamma ~ 2.5), very-high-energy-emitting (E > 100 GeV) gamma-ray blazar. Very-high-energy measurements of this active galactic…

High Energy Astrophysical Phenomena · Physics 2015-06-18 E. Aliu , S. Archambault , T. Arlen , T. Aune , B. Behera , M. Beilicke , W. Benbow , K. Berger , R. Bird , A. Bouvier , J. H. Buckley , V. Bugaev , K. Byrum , M. Cerruti , X. Chen , L. Ciupik , M. P. Connolly , W. Cui , C. Duke , J. Dumm , M. Errando , A. Falcone , S. Federici , Q. Feng , J. P. Finley , H. Fleischhack , P. Fortin , L. Fortson , A. Furniss , N. Galante , G. H. Gillanders , S. Griffin , S. T. Griffiths , J. Grube , G. Gyuk , D. Hanna , J. Holder , G. Hughes , T. B. Humensky , C. A. Johnson , P. Kaaret , M. Kertzman , Y. Khassen , D. Kieda , H. Krawczynski , F. Krennrich , M. J. Lang , A. S Madhavan , G. Maier , P. Majumdar , S. McArthur , A. McCann , K. Meagher , J. Millis , P. Moriarty , R. Mukherjee , D. Nieto , A. O'Faolain de Bhroithe , R. A. Ong , A. N. Otte , N. Park , J. S. Perkins , M. Pohl , A. Popkow , H. Prokoph , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , G. T. Richards , E. Roache , G. H. Sembroski , A. W. Smith , D. Staszak , I. Telezhinsky , M. Theiling , A. Varlotta , V. V. Vassiliev , S. Vincent , S. P. Wakely , T. C. Weekes , A. Weinstein , R. Welsing , D. A. Williams , A. Zajczyk , B. Zitzer

Hunting extreme BL Lacertae blazars with Fermi-LAT

The emission of very-high-energy photons (VHE, E>100 GeV$) in blazars is closely connected to the production of ultra-relativistic particles and the role of these gamma-ray sources as cosmic particle accelerators. This work focuses on a…

High Energy Astrophysical Phenomena · Physics 2022-03-04 M. Nievas Rosillo , A. Domínguez , G. Chiaro , G. La Mura , A. Brill , V. S. Paliya

Status And Highlights Of VERITAS

VERITAS (Very Energetic Radiation Imaging Telescope Array System) is an array of atmospheric Cherenkov telescopes sensitive to very high energy (VHE) gamma-rays above 100 GeV. Located at the Fred Lawrence Whipple Observatory in southern…

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

Long-term TeV Observations of the Gamma-ray Binary HESS J0632+057 with VERITAS

The gamma-ray binary HESS J0632+057 has been observed at very-high energies for almost ten years by all major systems of imaging atmospheric Cherenkov telescopes. We present new observations taken by the VERITAS observatory and an updated…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Gernot Maier

VERITAS Observations of Six Bright, Hard-Spectrum Fermi-LAT Blazars

We report on VERITAS very-high-energy (VHE; E>100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band,…

High Energy Astrophysical Phenomena · Physics 2015-06-11 E. Aliu , S. Archambault , T. Arlen , T. Aune , M. Beilicke , W. Benbow , M. Bottcher , A. Bouvier , J. H. Buckley , V. Bugaev , A. Cesarini , L. Ciupik , E. Collins-Hughes , M. P. Connolly , W. Cui , R. Dickherber , C. Duke , J. Dumm , M. Errando , A. Falcone , S. Federici , Q. Feng , J. P. Finley , G. Finnegan , L. Fortson , A. Furniss , N. Galante , D. Gall , S. Godambe , S. Griffin , J. Grube , G. Gyuk , D. Hanna , J. Holder , H. Huan , P. Kaaret , N. Karlsson , Y. Khassen , D. Kieda , H. Krawczynski , F. Krennrich , K. Lee , A. S Madhavan , G. Maier , P. Majumdar , S. McArthur , A. McCann , P. Moriarty , R. Mukherjee , T. Nelson , A. O'Faolain de Bhroithe , R. A. Ong , M. Orr , A. N. Otte , N. Park , J. S. Perkins , A. Pichel , M. Pohl , H. Prokoph , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , E. Roache , D. B. Saxon , G. H. Sembroski , D. Staszak , I. Telezhinsky , G. Tesic , M. Theiling , S. Thibadeau , K. Tsurusaki , A. Varlotta , V. V. Vassiliev , S. Vincent , M. Vivier , S. P. Wakely , T. C. Weekes , A. Weinstein , R. Welsing , D. A. Williams , B. Zitzer , P. Fortin , D. Horan , M. Fumagalli , K. Kaplan , J. X. Prochaska

Very High-Energy ($>$50 GeV) Gamma-ray Flux Variability of Bright Fermi Blazars

Understanding the high-energy emission processes and variability patterns are two of the most challenging research problems associated with relativistic jets. In particular, the long-term (months-to-years) flux variability at very high…

High Energy Astrophysical Phenomena · Physics 2024-01-23 Vaidehi S. Paliya

Catalog of very-high-energy emitting active galactic nuclei at high Galactic latitudes

Large number of Active Galactic Nuclei (AGN) producing Very-High-Energy (VHE) gamma-rays (energies above 100~GeV) has been revealed using observations with Imaging Atmospheric Cherenkov Telescopes (IACTs). However, our knowledge of the VHE…

High Energy Astrophysical Phenomena · Physics 2025-06-11 A. Neronov , D. Semikoz

TeV and Multi-wavelength Observations of Mrk 421 in 2006-2008

We report on TeV gamma-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV gamma-ray fluxes and…

High Energy Astrophysical Phenomena · Physics 2011-08-12 V. A. Acciari , E. Aliu , T. Arlen , T. Aune , M. Beilicke , W. Benbow , D. Boltuch , S. M. Bradbury , J. H. Buckley , V. Bugaev , K. Byrum , A. Cannon , A. Cesarini , L. Ciupik , W. Cui , R. Dickherber , C. Duke , A. Falcone , J. P. Finley , G. Finnegan , L. Fortson , A. Furniss , N. Galante , D. Gall , G. H. Gillanders , S. Godambe , J. Grube , R. Guenette , G. Gyuk , D. Hanna , J. Holder , C. M. Hui , T. B. Humensky , A. Imran , P. Kaaret , N. Karlsson , M. Kertzman , D. Kieda , A. Konopelko , H. Krawczynski , F. Krennrich , M. J. Lang , G. Maier , S. McArthur , M. McCutcheon , P. Moriarty , R. A. Ong , A. N. Otte , M. Ouellette , D. Pandel , J. S. Perkins , A. Pichel , M. Pohl , J. Quinn , K. Ragan , L. C. Reyes , P. T. Reynolds , E. Roache , H. J. Rose , A. C. Rovero , M. Schroedter , G. H. Sembroski , G. Demet Senturk , D. Steele , S. P. Swordy , M. Theiling , S. Thibadeau , A. Varlotta , V. V. Vassiliev , S. Vincent , R. G. Wagner , S. P. Wakely , J. E. Ward , T. C. Weekes , A. Weinstein , T. Weisgarber , D. A. Williams , S. Wissel , M. Wood , B. Zitzer , A. Garson , K. Lee , A. C. Sadun , M. Carini , D. Barnaby , K. Cook , J. Maune , A. Pease , S. Smith , R. Walters , A. Berdyugin , E. Lindfors , K. Nilsson , M. Pasanen , J. Sainio , A. Sillanpaa , L. O. Takalo , C. Villforth , T. Montaruli , M. Baker , A. Lahteenmaki , M. Tornikoski , T. Hovatta , E. Nieppola , H. D. Aller , M. F. Aller

VERITAS Observations of High-Frequency-Peaked BL Lac Objects

Here we present highlights from VERITAS observations of high-frequency-peaked BL Lac objects (HBLs). We discuss the key science motivations for observing these sources -- including performing multiwavelength campaigns critical to…

High Energy Astrophysical Phenomena · Physics 2019-08-13 M. Orr

Hunting Very High-Energy ($>$100 GeV) Emitting High-Synchrotron Peaked Blazars

Very-high energy (VHE; $>$100 GeV) $\gamma$-ray emission originates via some of the most extreme particle acceleration processes in the universe. Considering beamed active galactic nuclei, i.e., blazars, only a small fraction, mainly high…

High Energy Astrophysical Phenomena · Physics 2025-12-10 Sushmita Agarwal , Vaidehi S. Paliya