Eur. Phys. J. C (2009) 63: 139-147
https://doi.org/10.1140/epjc/s10052-009-1086-z

Regular Article - Theoretical Physics

Reconstructing the cosmic expansion history up to redshift z=6.29 with the calibrated gamma-ray bursts

¹ Department of Physics, Beijing Institute of Technology, Beijing, 100081, China
² Department of Physics and Tsinghua Center for Astrophysics, Tsinghua University, Beijing, 100084, China
³ Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China
⁴ Physics Department, University of Alabama in Huntsville, Huntsville, AL, 35899, USA

^* e-mail: haowei@bit.edu.cn

Received: 20 March 2009
Revised: 28 May 2009
Published online: 2 July 2009

Abstract

Recently, Gamma-Ray Bursts (GRBs) were proposed to be a complementary cosmological probe to type Ia supernovae (SNIa). GRBs have been advocated to be standard candles since several empirical GRB luminosity relations were proposed as distance indicators. However, there is a so-called circularity problem in the direct use of GRBs. Recently, a new idea to calibrate GRBs in a completely cosmology independent manner has been proposed, and the circularity problem can be solved. In the present work, following the method proposed by Liang et al., we calibrate 70 GRBs with the Amati relation using 307 SNIa. Then, following the method proposed by Shafieloo et al., we smoothly reconstruct the cosmic expansion history up to redshift z=6.29 with the calibrated GRBs. We find some new features in the reconstructed results.