Relative spectral lag: an new redshift indicator to measure the cosmos with gamma-ray bursts

Zhi-Bin Zhang, Jia-Gan Deng, Rui-Jing Lu +1

Using 64 ms count data for long gamma-ray bursts ($T_{90}>$2.6s), we analyze the quantity, relative spectral lag (RSL), which is defined as ${\tau }_{31}/FWH{M}_{(1)}$, where ${\tau }_{31}$ is t…