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arXiv · 2202.00314

The white dwarf binary merger model of GRB 170817A

J. A. Rueda·R. Ruffini·Liang Li·R. Moradi·N. Sahakyan·Y. Wang
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Abstract

Following the GRB 170817A prompt emission lasting a fraction of a second, $10^8$ s of data in the X-rays, optical, and radio wavelengths have been acquired. We here present a model that fits the spectra, flux, and time variability of all these emissions, based on the thermal and synchrotron cooling of the expanding matter ejected in a binary white dwarf merger. The $10^{-3} M_\odot$ of ejecta, expanding at velocities of $10^9$ cm s$^{-1}$, are powered by the newborn massive, fast rotating, magnetized white dwarf with a mass of $1.3 M_\odot$, a rotation period of $\gtrsim 12$ s, and a dipole magnetic field $\sim 10^{10}$ G, born in the merger of a $1.0+0.8 M_\odot$ white dwarf binary. Therefore, the long-lasting mystery of the GRB 170817A nature is solved by the merger of a white dwarf binary that also explains the prompt emission energetics.

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J. A. Rueda, R. Ruffini, Liang Li, R. Moradi, N. Sahakyan, Y. Wang. 2022-02-01. The white dwarf binary merger model of GRB 170817A. https://doi.org/10.1142/s0218271822300130

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