2010/12/14 by Ryo Tsutsui, T. Nakamura, Takashi Nakamura +8
Physics and Astronomy · #Astronomy and Astrophysical Research #FOS: Physical sciences #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #astro-ph.HE
paper · pdf · doi:10.48550/arxiv.1012.3009
11 pages, 1 figure, submitted to ApJ Letter
arxiv created 2010/12/14 · openalex publication_date 2010/12/14 · arxiv updated 2010/12/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We reconsider correlations among the spectral peak energy (Ep), 1-second peak luminosity (Lp) and isotropic energy (\Eiso), using the database constructed by \citetyonetoku10 which consists of 109 Gamma-Ray Bursts (GRBs) whose redshifts are known and Ep, Lp and \Eiso are well determined. We divide the events into two groups by their data quality. One (gold data set) consists of GRBs with peak energies determined by the Band model with four free parameters. On the other hand, GRBs in the other group (bronze data set) have relatively poor energy spectra so that their peak energies were determined by the Band model with fixed spectral index (i.e. three free parameters) or by the Cut-off power law (CPL) model with three free parameters. Using only the gold data set we found the intrinsic dispersion in log Lp (=σ\rm int) is 0.13 and 0.22 for \tsutsui correlation (TL ≡ E\rm iso/Lp) and \yonetoku correlation, respectively. We also find that GRBs in the bronze data set have systematically larger Ep than expected by the correlations constructed with the gold data set. This means that the intrinsic dispersion of correlations among Ep, Lp, and \Eiso of GRBs depends on the quality of data set. At present, using \tsutsui correlation with gold data set, we would be able to determine the luminosity distance with ∼ 16% error, which might be useful to determine the nature of the dark energy at high redshift z > 3.