Spectrum of very high energy gamma-rays from the blazar 1ES 1959+650 during flaring activity in 2002

  • M. K. Daniel
  • , H. M. Badran
  • , I. H. Bond
  • , P. J. Boyle
  • , S. M. Bradbury
  • , J. H. Buckley
  • , D. A. Carter-Lewis
  • , M. Catanese
  • , O. Celik
  • , P. Cogan
  • , W. Cui
  • , M. D'Vali
  • , I. De La Calle Perez
  • , C. Duke
  • , A. Falcone
  • , D. J. Fegan
  • , S. J. Fegan
  • , J. P. Finley
  • , L. F. Fortson
  • , J. A. Gaidos
  • S. Gammell, K. Gibbs, G. H. Gillanders, J. Grube, J. Hall, T. A. Hall, D. Hanna, A. M. Hillas, J. Holder, D. Horan, T. B. Humensky, A. Jarvis, M. Jordan, G. E. Kenny, M. Kertzman, D. Kieda, J. Kildea, J. Knapp, K. Kosack, H. Krawczynski, F. Krennrich, M. J. Lang, S. L.E. Bohec, E. Linton, J. Lloyd-Evans, A. Milovanovic, P. Moriarty, D. Müller, T. Nagai, S. Nolan, R. A. Ong, R. Pallassini, D. Petry, B. Power-Mooney, J. Quinn, M. Quinn, K. Ragan, P. Rebillot, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, S. P. Swordy, A. Syson, V. V. Vassiliev, S. P. Wakely, G. Walker, T. C. Weekes, J. Zweerink

Research output: Contribution to journalArticlepeer-review

Abstract

The blazar 1ES 1959+650 was observed in a flaring state with the Whipple 10 m Imaging Atmospheric Cerenkov Telescope in 2002 May. A spectral analysis has been carried out on the data from that time period, and the resulting very high energy gamma-ray spectrum (E ≥ 316 GeV) can be well fitted by a power law of differential spectral index α = 2.78 ± 0.12stat ± 0.21sys. On 2002 June 4, the source flared dramatically in the gamma-ray range without any coincident increase in the X-ray emission, providing the first unambiguous example of an "orphan" gamma-ray flare from a blazar. The gamma-ray spectrum for these data can also be described by a simple power-law fit with α = 2.82 ± 0.15stat ± 0.30sys. There is no compelling evidence for spectral variability or for any cutoff to the spectrum.

Original languageEnglish (US)
Pages (from-to)181-187
Number of pages7
JournalAstrophysical Journal
Volume621
Issue number1 I
DOIs
StatePublished - Mar 1 2005

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'Spectrum of very high energy gamma-rays from the blazar 1ES 1959+650 during flaring activity in 2002'. Together they form a unique fingerprint.

Cite this