Related papers: VERITAS Blazar Observations - Recent Results
Observations of very high energy gamma-rays from blazars provide information about acceleration mechanisms occurring in their innermost regions. Studies of variability in these objects allow a better understanding of the mechanisms at play.…
1RXS J101015.9-311909 is a galaxy located at a redshift of z=0.14 hosting an active nucleus belonging to the class of bright BL Lac objects. Observations at high (HE, E > 100 MeV) and very high (VHE, E > 100 GeV) energies provide insights…
In December 2023, the Large-Sized Telescope prototype (LST-1) detected for the first time VHE $\gamma$-ray emission from the FSRQ OP~313 becoming the furthest blazar ever observed at VHE with z=0.997. We aim to characterize the $\gamma$-ray…
The flat spectrum radio quasar PKS 1510-089 is a monitored target in many wavelength bands due to its high variability. It was detected as a very-high-energy (VHE) $\gamma$-ray emitter with H.E.S.S. in 2009, and has since been a regular…
VERITAS, the Very Energetic Radiation Telescope Imaging Array System, is an array of four imaging Atmospheric Cherenkov telescopes in southern Arizona. It is sensitive to gamma rays at energies above 100 GeV. Here, we discuss the results of…
Ground-based $\gamma$-ray observatories, such as the VERITAS array of imaging atmospheric Cherenkov telescopes, provide insight into very-high-energy (VHE, $\mathrm{E}>100\,\mathrm{GeV}$) astrophysical transient events. Examples include the…
The extragalactic VHE gamma-ray sky is rich in blazars. These are jetted active galactic nuclei viewed at a small angle to the line-of-sight. Only a handful of objects viewed at a larger angle are known so far to emit above 100 GeV.…
The close X-ray selected BL Lac PKS 2155-304 has been observed using the University of Durham Mark 6 very high energy (VHE) gamma ray telescope during 1996 September/October/November and 1997 October/November. VHE gamma rays with energy >…
A detailed multi-epoch study of the broadband spectral behaviour of the very high energy (VHE) source, 1ES\,1011+496, provides us with valuable information regarding the underlying particle distribution. Simultaneous observations of the…
In this paper we report the \textit{Fermi} Large Area Telescope (LAT) detection of Very High Energy (VHE; $E_{\gamma}>100$ GeV) $\gamma$-ray emission from the BL Lac object RBS 0679. $5.3$ years of LAT observations revealed the presence of…
We present results of very-high-energy gamma-ray observations (E > 160 GeV) of two high-frequency-peaked BL Lac (HBL) objects, 1ES 1218+304 and H 1426+428, with the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE). Both sources…
High-energy observations of extreme BL Lac objects, such as 1ES0229+200 or 1ES 0347-121, recently focused interest both for blazar and jet physics and for the implication on the extragalactic background light and intergalactic magnetic…
The blazar PG 1553+113 is a well known TeV gamma-ray emitter. In this paper, we determine its spectral energy distribution using simultaneous multi-frequency data in order to study its emission processes. An extensive campaign was carried…
Significant gamma-ray emission between 1 TeV and 20 TeV from a point source, 1LHAASO J1219+2915, consistent with the location of the LINER/LLAGN galaxy NGC 4278 was recently reported by the LHAASO collaboration. These data were later split…
Spectral fitting of the radio through hard X-ray emission of BL Lac objects has previously been used to predict their level of high-energy (GeV - TeV) emission. In this paper, we point out that such spectral fitting can have very large…
Most of the extragalactic objects detected so far in the very high energy (VHE) regime are blazars, but the discovered nearby radio galaxies: M87, Cen A and NGC 1275 of type FRI seem to constitute a new class of VHE emitters. The radio…
We report multiwavelength observations of the gravitationally lensed blazar QSO B0218+357 in 2016-2020. Optical, X-ray and GeV flares were detected. The contemporaneous MAGIC observations do not show significant very-high-energy (VHE, >=…
The well-studied VHE (E >100 GeV) blazar Mrk 501 was observed between March and May 2008 as part of an extensive multiwavelength observation campaign including radio, optical, X-ray and VHE gamma-ray instruments. Mrk 501 was in a low state…
The high energy blazar, Markarian 501 was observed as a part of multi-instrument and multiwavelength campaign spanning the whole electromagnetic spectrum for 4.5 months during March 15 to August 1, 2009. On May 1, Whipple 10m telescope…
The VERITAS array of Cherenkov telescopes was used to observe ~130 blazars from 2007 to 2012. Of these, 25 were detected as very-high-energy (VHE; E > 100 GeV) sources. We present here the results of the analysis of 65 VERITAS non-detected…