Campana 2007 Ghirlanda关系在加入Swift数据后变差

主要内容:
Ghirlanda关系以及Liang-Zhang关系，在增加了Swift数据之后其致密性变差，可能不能用于标准烛光关系。

精彩摘抄:


文章信息:
Are Swift gamma-ray bursts consistent with the Ghirlanda relation?

Authors: S. Campana (1), C. Guidorzi (2,1), G. Tagliaferri (1), G. Chincarini (2,1), A. Moretti (1), D. Rizzuto (2,1), P. Romano (1,2) (1, Osservatorio Astronomico di Brera), (2, Universita` degli studi di Milano-Bicocca)

(Submitted on 27 Mar 2007 (v1), last revised 16 Apr 2007 (this version, v2))

Abstract: A few tight correlations linking several properties of gamma-ray bursts (GRBs), namely the spectral peak energy, the total radiated energy, and the afterglow break time, have been discovered with pre-Swift GRBs. They were used to constrain the cosmological parameters, together with type-Ia supernovae. However, the tightness of these correlations is a challenge to GRB models. We explore the effect of adding Swift bursts to the Ghirlanda and Liang-Zhang relations. Although they are both still valid, they become somewhat weakened mostly due to the presence of significant outliers, which otherwise are apparently normal GRBs so difficult to distinguish. The increased dispersion of the relations makes them less reliable for purposes of precision cosmology.

Comments:

Paper accepted for publication on A&A (7 pages, 2 figures). Small changes after comments

Subjects:

Astrophysics (astro-ph)

Cite as:

arXiv:astro-ph/0703676v2