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Title: Discovery of a new TeV gamma-ray source: VER J0521+211

Journal Article · · The Astrophysical Journal

Here, we report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov Telescope Array. These observations were motivated by the discovery of a cluster of >30 GeV photons in the first year of Fermi Large Area Telescope observations. VER J0521+211 is relatively bright at TeV energies, with a mean photon flux of (1.93 ± 0.13stat ± 0.78sys) × 10–11 cm–2 s–1 above 0.2 TeV during the period of the VERITAS observations. The source is strongly variable on a daily timescale across all wavebands, from optical to TeV, with a peak flux corresponding to ~0.3 times the steady Crab Nebula flux at TeV energies. Follow-up observations in the optical and X-ray bands classify the newly discovered TeV source as a BL Lac-type blazar with uncertain redshift, although recent measurements suggest z = 0.108. VER J0521+211 exhibits all the defining properties of blazars in radio, optical, X-ray, and gamma-ray wavelengths.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Organization:
USDOE
Contributing Organization:
The VERITAS Collaboration
Grant/Contract Number:
AC02-76SF00515
OSTI ID:
1356558
Journal Information:
The Astrophysical Journal, Vol. 776, Issue 2; ISSN 0004-637X
Publisher:
Institute of Physics (IOP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 23 works
Citation information provided by
Web of Science

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Cited By (8)

GeV-TeV γ $\gamma $ -ray energy spectral break of BL Lac objects journal August 2018
The most powerful flaring activity from the NLSy1 PMN J0948+0022 journal November 2014
On the Redshift of TeV BL Lac Objects journal March 2017
A Decade of Multiwavelength Observations of the TeV Blazar 1ES 1215+303: Extreme Shift of the Synchrotron Peak Frequency and Long-term Optical–Gamma-Ray Flux Increase journal March 2020
The most powerful flaring activity from the NLSy1 PMN J0948+0022 text January 2015
A Decade of Multiwavelength Observations of the TeV Blazar 1ES 1215+303: Extreme Shift of the Synchrotron Peak Frequency and Long-term Optical–Gamma-Ray Flux Increase text January 2020
The extragalactic background light, the Hubble constant, and anomalies: conclusions from 20 years of TeV gamma-ray observations text January 2015
A decade of multi-wavelength observations of the TeV blazar 1ES 1215+303: Extreme shift of the synchrotron peak frequency and long-term optical-gamma-ray flux increase text January 2020

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