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An independent estimate of the cosmological distance to GRB970228 and GRB970508

V. M. Lipunov·K. A. Postnov·M. E. Prokhorov
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Abstract

Assuming binary neutron star mergings as a standard-candle model for GRBs, an independent estimate is obtained for the redshift of GRB970228 and GRB970508 with optical counterparts, using mean statistical properties of GRBs observed by BATSE. We derive z=0.7\pm 0.1 and z=1.9\pm 0.1 for GRB970228 and GRB970508 respectively, depending on the power-law index of the GRB spectrum s=-1.1\pm 0.3 and the value of the redshift of the initial star formation z_*=3-10 in a flat Ω=1 Universe with a cosmological term Λ=0.7.

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V. M. Lipunov, K. A. Postnov, M. E. Prokhorov. 1997-05-13. An independent estimate of the cosmological distance to GRB970228 and GRB970508. https://arxiv.org/abs/astro-ph/9703181

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