http://arxiv.org/abs/1402.5463
Using 72 Short Gamma Ray Bursts (SGRBs) with well determined spectral data observed by BATSE, we determine their redshift and the luminosity by applying $E_p$–$L_p$ correlation for SGRBs found by Tsutsui et al. (2013). For 53 SGRBs with the observed flux brighter than $4 \times 10^{-6}~{\rm erg~cm^{-2}s^{-1}}$, the cumulative redshift distribution up to $z=1$ agrees well with that of 22 Swift SGRBs. Especially good agreement is seen for $z < 0.4$ with the KS chance probability of 5.3\%. This suggests that the redshift determination by the $E_p$–$L_p$ correlation for SGRBs works very well. The minimum event rate at $z=0$ is estimated as $R_{\rm on-axis}^{\rm min} = 2 \times 10^{-10}~{\rm events~Mpc^{-3}yr^{-1}}$ so that the minimum beaming angle is $0.57^\circ-3.6^\circ$ assuming the merging rate of $10^{-7}-4\times 10^{-6}~{\rm events~yr^{-1}galaxy^{-1}}$ suggested from the binary pulsar data. Interestingly, this angle is consistent with that for SGRB~130603B of $\sim 4^\circ-8^\circ$ (Fong et al. 2013). On the other hand, if we assume the beaming angle of $\sim 6^\circ$ suggested from four SGRBs, the minimum event rate including off-axis SGRBs is estimated as $R_{\rm all}^{\rm min}\sim 4\times 10^{-8}~{\rm events~Mpc^{-3}yr^{-1}}$. If SGRBs are induced by coalescence of binary neutron stars (NSs) and/or black holes (BHs), this event rate leads to the minimum gravitational-wave detection rate of $\rm 1.3 (50)~events~yr^{-1}$ for NS-NS (NS-BH) binary, respectively, by KAGRA, adv-LIGO, adv-Virgo and GEO network.
D. Yonetoku, T. Nakamura, K. Takahashi, et. al.
Tue, 25 Feb 14
49/59