English

GRB 060218 and the outliers with respect to the Ep-Eiso correlation

Astrophysics 2017-08-23 v1

Abstract

GRB 031203 and GRB 980425 are the two outliers with respect to the Ep-Eiso correlation of long GRBs. Recently Swift discovered a nearby extremely long GRB 060218 associated with a SN event. The spectral properties of this bursts are striking: on the one hand its broad band SED presents both thermal and non-thermal components which can be interpreted as due to the emission from the hot cocoon surrounding the GRB jet and as standard synchrotron self absorbed emission in the GRB prompt phase, respectively; on the other hand it is its long duration and its hard--to--soft spectral evolution which make this underluminous burst consistent with the Ep-Eiso correlation of long GRBs. By comparing the available spectral informations on the two major outliers we suggests that they might be twins of 060218 and, therefore, only apparent outliers with respect to the Ep_Eiso correlation. This interpretation also suggests that it is of primary importance the study the broad band spectra of GRBs in order to monitor their spectral evolution throughout their complete duration.

Keywords

Cite

@article{arxiv.astro-ph/0702004,
  title  = {GRB 060218 and the outliers with respect to the Ep-Eiso correlation},
  author = {G. Ghirlanda and G. Ghisellini},
  journal= {arXiv preprint arXiv:astro-ph/0702004},
  year   = {2017}
}

Comments

To appear in the conference proceeding of the IV workshop on "Science with the new generation of high energy Gamma-Ray Experiment", 20-22 June 2006, Isola d'Elba