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

  title={Evidence for anisotropy in the distribution of short-lived gamma-ray bursts},
  author={M Magliocchetti and Giancarlo Ghirlanda and Annalisa Celotti},
  journal={Monthly Notices of the Royal Astronomical Society},
Measurements of the two-point angular correlation function w(θ) for 407 short gamma-ray bursts collected in the Current BATSE Catalogue reveal a ∼2σ deviation from isotropy on angular scales 0 ∼ 2°-4°. 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 per cent of the sources under exam. However, the available data cannot exclude the signal as due to the presence of large-scale structure. Under this… Expand

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