Method of determining cosmological parameter ranges with samples of candles with an intrinsic distribution

• 来源期刊: 中国物理（英文版）
• 关键词: cosmological parameters observational cosmology distance scale
• 年，卷（期）: 2006,（7）
• 页码范围: 1645-1652
• 页数: 8页
• 语种: 英文

摘要

In this paper, the effect of the intrinsic distribution of cosmological candles is investigated. We find that in the case of a narrow distribution the deviation of the observed modulus of sources from the expected central value can be estimated within a ceratin range. We thus introduce lower and upper limits of χ2, χ2min and χ2max to estimate cosmological parameters by applying the conventional minimizing χ2 method. We apply this method to a gammaray burst (GR2 sample as well as to a combined sample including this GRB sample and an SN Ia sample. Our analysis shows that: 1 in the case of assuming an intrinsic distribution of candles of the GRB sample, the effect of the distribution is obvious and should not be neglected; 2 taking into account this effect would lead to a poorer constraint of the cosmological parameter ranges. The analysis suggests that in the attempt of constraining the cosmological model with current GRB samples, the results tend to be worse than was previously anticipated if the mentioned intrinsic distribution does exist.