The exceptional TeV flaring activity of the blazar 1ES 1959+650 in 2015 and 2016 as observed with VERITAS

Understand

The high-synchrotron-peaked blazar 1ES 1959+650 was among the first extragalactic sources detected in the very high energy gamma ray band (VHE, E > 100 GeV).

• In October 2015, the source entered an extended period of activity that continued through July 2016, during which several strong VHE flares were observed.
• This flaring activity in the TeV band was accompanied by a strong increase in the optical, X-ray, and GeV gamma-ray flux of the source, surpassing its brightest recorded flux states.
• The VERITAS telescope array performed observations of 1ES 1959+650 between October 2015 and June 2016, and detected the source multiple times at a flux higher than the Crab nebula flux in the TeV band, representing the brightest flares of this object since 2002.