... Dead time corrections are not considered explicitly in the current version of this task, as it is expected that the EXPOSURE attribute, written to the spectral file by evselect (see also Julian Osborne's proposal regarding exposure-type attributes available on the SOC web server), should take into account dead time effects. arfgen calls the task attcalc internally. ... Note that the intermediate event dataset also contains attributes used to initialise the CAL in the subsequent call by attcalc . ...