Fermi Gamma-ray Space Telescope

Very high energy gamma-ray follow-up observations of novae and dwarf novae with the MAGIC telescopes.

Julian Sitarek
W. Bednarek, R. Lopez-Coto, E. de Ona Wilhelmi for the MAGIC Collaboration, F. Longo, R. Desiante, E. Hays for the Fermi Collaboration

Abstract:

In the last few years the Fermi-LAT instrument has detected GeV gamma-ray emission from a few novae. Such GeV emission can be interpreted in terms of an inverse Compton process of electrons accelerated in a shock. It is expected that hadrons can be accelerated in the same conditions, but reaching much higher energies. They can produce a second component in the gamma-ray spectrum at the TeV energies. We perform follow up observations of selected novae and dwarf novae in a search of the second component in the gamma-ray spectrum. This can shed light on the acceleration process of leptons and hadrons in nova explosions. We have performed observations with the MAGIC telescopes of 3 sources, a symbiotic nova YY Her, a dwarf nova ASASSN-13ax and a classical nova V339 Del shortly after their outbursts. We confront the results of MAGIC TeV observations of V339 Del against the GeV detection by Fermi in order to evaluate the acceleration parameters for electrons and hadrons.