Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni

Abstract

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce X-ray emission but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray (0.1-10 GeV) emission from the recently-detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary, and that particles can be accelerated effectively to produce pi0 decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

38 pages, includes Supplementary Online Material; corresponding authors: C.C. Cheung, A.B. Hill, P. Jean, S. Razzaque, K.S. Wood

References in corpus (5)

• X-Ray Emitting Blast Wave from the Recurrent Nova RS Ophiuchi
• An asymmetric shock wave in the 2006 outburst of the recurrent nova RS Ophiuchi
• An Expanding Shell and Synchrotron Jet in RS Ophiuchi
• Evidence for nonlinear diffusive shock acceleration of cosmic-rays in the 2006 outburst of the recurrent nova RS Ophiuchi
• Novae as a Mechanism for Producing Cavities around the Progenitors of SN 2002ic and Other SNe Ia

Cited by in corpus (2)

• High Energy Neutrinos from Novae in Symbiotic Binaries: The Case of V407 Cygni
• Study of the gamma-ray source 1AGL J2022+4032 in the Cygnus Region