2003/01/15 by Maarten Schmidt, Schmidt, Maarten
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #Gamma-ray bursts and supernovae #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0301277
4 pages, 3 figures, contribution for Rome 2002 GRB Workshop
arxiv created 2003/01/15 · openalex publication_date 2003/01/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We review five studies of the gamma-ray burst (GRB) luminosity function that are based on one or more of the proposed luminosity criteria, i.e., variability, spectral lag and spectral hardness. A comparison between the resulting luminosity functions at redshift zero shows considerable divergence. We derive for each of the luminosity functions the expected source counts and the Euclidean value of . The source counts exhibit large differences from the observed counts. In most cases the value of differs substantially from the observed value of 0.34 for BATSE-based samples, with offsets ranging from 6-24 sigmas. Given that the value of is well established and that it is a cosmological distance indicator, we recommend that any study of the GRB luminosity function take its value into account.