The TeV Energy Spectrum of Mrk 421 Measured in A High Flaring State
arXiv:0708.3857 · doi:10.1086/588782
Abstract
The BL Lac object (blazar) Mrk 421 was observed during its outburst in April 2004 with the Whipple 10 m telescope for a total of about 24.5 hours. The measured gamma-ray rate varied substantially over the range from 4 to 10 gamma's/min and eventually exceeded the steady gamma-ray rate of the Crab Nebula (standard candle) by a factor of 3. The overall significance of the gamma-ray signal exceeded 70 sigma and the total number of excess events was more than 10,000. The signal light curve does not show any particular variability pattern. This unique Mrk 421 outburst enabled the measurement of a high quality spectrum of very high-energy gamma rays in a high state of emission. This spectrum is a power-law and it extends beyond 10 TeV.
arXiv comment4 pages, 5 figures, Proc. 30th International Cosmic Ray Conference, Merida, Mexico, 2007
References in corpus (8)
- A Multi-wavelength View of the TeV Blazar Markarian 421: Correlated Variability, Flaring, and Spectral Evolution
- Observations of Mkn 421 with the MAGIC Telescope
- Modelling the TeV gamma-ray spectra of two low redshift AGNs: Mkn 501 and Mkn 421
- Variations of the TeV energy spectrum at different flux levels of Mkn 421 observed with the HEGRA system of Cherenkov telescopes
- Simultaneous X-Ray and TeV Gamma-Ray Observations of the TeV Blazar Markarian 421 during February and May 2000
- Discovery of Spectral Variability of Markarian 421 at TeV Energies
- Observations of Mkn 421 in 2004 with H.E.S.S. at large zenith angles
- A New Analysis Method for Reconstructing the Arrival Direction of TeV Gamma-rays Using a Single Imaging Atmospheric Cherenkov Telescope