Context :

Aims : A hard X-ray shortage , implying the cooling of the corona , was observed during bursts of IGR J17473-272 , 4U 1636-536 , Aql X-1 , and GS 1826-238 .
Apart from these four sources , we investigate here an atoll sample , in which the number of bursts for each source is larger than 5 , to explore the possible additional hard X-ray shortage during Rossi X-ray timing explorer ( RXTE ) era .

Methods : According to the source catalog that shows type-I bursts , we analyzed all the available pointing observations of these sources carried out by the RXTE proportional counter array ( PCA ) .
We grouped and combined the bursts according to their outburst states and searched for the possible hard X-ray shortage while bursting .

Results : We found that the island states of KS 1731-260 and 4U 1705-44 show a hard X-ray shortage at significant levels of 4.5 and 4.7 \sigma and a systematic time lag of 0.9 \pm 2.1 s and 2.5 \pm 2.0 s with respect to the soft X-rays , respectively .
While in their banana branches and other sources , we did not find any consistent shortage .

Conclusions :