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arXiv · 1101.6013

Gamma-ray sources like V407 Cygni in Symbiotic Stars

Guoliang Lu·Chunhua Zhu·Zhaojun Wang·Wensheng Huo·Yuangui Yang
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Abstract

Using a simple accelerating model and an assumption that $\gamma$-rays originate from $p-p$ collisions for a $\pi^0$ model, we investigate $\gamma$-ray sources like V407 Cygni in symbiotic stars. The upper limit of their occurrence rate in the Galaxy is between 0.5 and 5 yr$^{-1}$, indicating that they may be an important source of the high-energy $\gamma$-rays. The maximum energies of the accelerated protons mainly distribute around $10^{11}$ eV, and barely reach $10^{15}$ eV. The novae occurring in D-type SSs with ONe WDs and long orbital periods are good candidates for $\gamma$-ray sources. Due to a short orbital period which results in a short acceleration duration, the nova occurring in symbiotic star RS Oph can not produce the $\gamma$-ray emission like that in V407 Cygni.

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Guoliang Lu, Chunhua Zhu, Zhaojun Wang, Wensheng Huo, Yuangui Yang. 2011-01-31. Gamma-ray sources like V407 Cygni in Symbiotic Stars. https://arxiv.org/abs/1101.6013

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