Context. The blazar 1 ES 1218+30.4 has been previously detected by the VERITAS and MAGIC telescopes in the very high energies. The new detection of VERITAS from December 2008 to April 2009 proves that 1 ES 1218+30.4 is not static, but shows short-time variability.
Aims: We show that the time variability may be explained in the context of a self-consistent synchrotron-self Compton model, while the long time observation do not necessarily require a time-resolved treatment.
Methods: The kinetic equations for electrons and photons in a plasma blob are solved numerically including Fermi acceleration for electrons as well as synchrotron radiation and Compton scattering.
Results: The light curve observed by VERITAS can be reproduced in our model by assuming a changing level of electron injection compared to the constant state of 1 ES 1218+30.4. The multiwavelength behaviour during an outburst becomes comprehensible by the model.
Conclusions: The long time measurements of VERITAS are still explainable via a constant emission in the SSC context, but the short outbursts each require a time-resolved treatment.
Astronomy and Astrophysics
- Pub Date:
- June 2010
- galaxies: jets;
- relativistic processes;
- radiation mechanisms: non-thermal;
- BL Lacertae objects: individual: 1 ES 1218+30.4;
- galaxies: active;
- Astrophysics - High Energy Astrophysical Phenomena;
- Astrophysics - Cosmology and Extragalactic Astrophysics
- 4 pages, 3 figures