The statistical shapes of the highest pulse have been studied by aligned method .
A wavelet package analysis technique and a developed pulse–finding algorithm have been applied to select the highest pulse from burst profiles observed by BATSE on board CGRO from 1991 April 21 to 1999 January 26 .
The results of this work show that the statistical shapes of the highest pulses are related to energy : the higher the energy , the narrower the pulse .
However , the characteristic structures of the pulses have nothing to do with energy , which strongly supports the previous conclusion that the temporal profiles in different channels are self–similar .
The characteristic structures of the pulses can be well described by a model proposed by Norris et al .
( 1996 ) .
The fitting parameters are : t _ { r } =0.12 , t _ { d } =0.16 , \upsilon = 1.09 , the ratio of t _ { r } to t _ { d } for the pulse is 0.75 .
The result leads to our conjecture that the mechanisms of bursts in different gamma-ray bands might be the same .
The shock , either an internal or an external one , producing the pulse , might emit photons over the four energy channels in the same way .