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Evidence for anisotropy in the distribution of short-lived gamma-ray bursts

M. Magliocchetti·G. Ghirlanda·A. Celotti
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Abstract

Measurements of the two-point angular correlation function w(θ) for 407 short gamma-ray bursts collected in the Current BATSE Catalogue reveal a ~2 σdeviation from isotropy on angular scales θ~ 2-4 degrees. Such an anisotropy is not observed in the distribution of long gamma-ray bursts and hints to the presence of repeated bursts for up to ~13% of the sources under exam. However, the available data cannot exclude the signal as due to the presence of large-scale structure. Under this assumption, the amplitude of the observed w(θ) is compatible with those derived for different populations of galaxies up to redshifts ~0.5, result that suggests short gamma-ray bursts to be relatively local sources.

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M. Magliocchetti, G. Ghirlanda, A. Celotti. 2003-02-02. Evidence for anisotropy in the distribution of short-lived gamma-ray bursts. https://doi.org/10.1046/j.1365-8711.2003.06657.x

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