Finding peaks in the detector countrate is performed by program 'whkproc'. Per detected peak a row is stored in a FITS file. The information stored is risetime and falltime of the peak, the countrate at the peak maximum, and the total counts of the peak above the running average. The algorithm for finding a peak is based on the count rate of the input event processor. This countrate is available every second in the Science Housekeeping data. The FITS keyword for the column containing these values is 'RATE_EVENT'. At any point the counts of a fixed number of seconds (currently 50) are buffered and used to find a peak. A peak is accepted if the distance to the falltime of a previous peak is at least a predetermined number of seconds (presently 3) and if for at most a fixed number of succesive counts (presently 24) counts are above the buffer average by at least a fixed number (presently 100)