A Search for Enhanced Very High Energy Gamma-Ray Emission from the 2013 March Crab Nebula Flare
Abstract
In 2013 March, a flaring episode from the Crab Nebula lasting ~2 weeks was detected by Fermi-LAT (Large Area Telescope on board the Fermi Gamma-ray Space Telescope). The Very Energetic Radiation Imaging Telescope Array System (VERITAS) provides simultaneous observations throughout this period. During the flare, Fermi-LAT detected a 20 fold increase in flux above the average synchrotron flux >100 MeV seen from the Crab Nebula. Simultaneous measurements with VERITAS are consistent with the non-variable long-term average Crab Nebula flux at TeV energies. Assuming a linear correlation between the very high energy flux change >1 TeV and the flux change seen in the Fermi-LAT band >100 MeV during the period of simultaneous observations, the linear correlation factor can be constrained to be at most 8.6 × 10-3 with 95% confidence.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 2014
- DOI:
- 10.1088/2041-8205/781/1/L11
- arXiv:
- arXiv:1309.5949
- Bibcode:
- 2014ApJ...781L..11A
- Keywords:
-
- gamma rays: general;
- ISM: individual objects: Crab Nebula;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 4 figures, 1 table, published in The Astrophysical Journal Letters