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تسجيل مستخدم جديدGravitational-wave bursts from soft gamma-ray repeaters: Can they be detected?
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H. J. Mosquera Cuesta
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In this letter we suggest a scenario for simultaneous emission of gravitational-wave and $gamma$-ray bursts (GRBs) from soft gamma-ray repeaters (SGRs). we argue that both of the radiations can be generated by a super-Eddington accreting neutron stars in X-ray binaries. In this model a supercritical accretion transient takes back onto the remnant star the disk leftover by the hydrodynamic instability phase of a low magnetized, rapidly rotating neutron star in a X-ray binary system. We estimate the rise timescale $Delta t_c = 0.21 ms$, minimum mass accretion rate needed to trigger the $gamma$-ray emission, $dot{M}_lambda = 4.5 times 10^{28} g$, and its effective associated temperature $T_{eff} = 740 keV$, and the timescale for repeating a burst of $gamma$-rays $Delta tau_R = 11.3 yr$. Altogether, we find the associated GW amplitude and frequency to be $h_c = 2.7 times 10^{-23}/{(Hz)}^{1/2}$ and $f_{gw} = 966 Hz$, for a source distance $sim 55 kpc$. Detectability of the pulses by t he forthcoming GW anntenas is discussed and found likely.
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