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arXiv · 1209.0854

Nonthermal processes and neutrino emission from the black hole GRO J0422+32 in a bursting state

F. L. Vieyro·Y. Sestayo·G. E. Romero·J. M. Paredes
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Abstract

GRO J0422+32 is a member of the class of low-mass X-ray binaries (LMXBs). It was discovered during an outburst in 1992. During the entire episode a persistent power-law spectral component extending up to $\sim 1$ MeV was observed, which suggests that nonthermal processes should have occurred in the system. We study relativistic particle interactions and the neutrino production in the corona of GRO J0422+32, and explain the behavior of GRO J0422+32 during its recorded flaring phase. We have developed a magnetized corona model to fit the spectrum of GRO J0422+32 during the low-hard state. We also estimate neutrino emission and study the detectability of neutrinos with 1 km$^3$ detectors, such as IceCube. The short duration of the flares ($\sim$ hours) and an energy cutoff around a few TeV in the neutrino spectrum make neutrino detection difficult. There are, however, many factors that can enhance neutrino emission. The northern-sky coverage and full duty cycle of IceCube make it possible to detect neutrino bursts from objects of this kind through time-dependent analysis.

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F. L. Vieyro, Y. Sestayo, G. E. Romero, J. M. Paredes. 2012-09-05. Nonthermal processes and neutrino emission from the black hole GRO J0422+32 in a bursting state. https://doi.org/10.1051/0004-6361/201219961

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