6.2.1. *L* iso–*τ*lag Correlation

This correlation holds for LGRBs and indicates that the more luminous bursts possess shorter time lags, i.e., *L*iso ∝ *τ* −1.25 lag [129]. It has been used as a GRB redshift indicator and to constrain cosmological parameters. However, the existence of this correlation is challenged by recent studies. For details, see Ref. [130].
