Three Types of Gamma-Ray Bursts

  title={Three Types of Gamma-Ray Bursts},
  author={Soma Mukherjee and Eric D. Feigelson and Gutti Jogesh Babu and Fionn Murtagh and Chris Fraley and Adrian E. Raftery},
  journal={The Astrophysical Journal},
  pages={314 - 327}
A multivariate analysis of gamma-ray burst (GRB) bulk properties is presented to discriminate between distinct classes of GRBs. Several variables representing burst duration, fluence, and spectral hardness are considered. Two multivariate clustering procedures are used on a sample of 797 bursts from the Third BATSE Catalog, a nonparametric average linkage hierarchical agglomerative clustering procedure validated with Wilks' Λ* and other multivariate analysis of variance tests and a parametric… 

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