History of processing versions
This table lists the processing version together with the software and calibration releases for the data present in the archive. The first column is the date when the processing version was moved into production, the second column gives the processing version number, the third is the NICER and Heasoft software release version and the last the caldb version. The software version and caldb version are written in the FITS file in the keywords SOFTVER and CALDBVER. Note that if the processing version increses when the software and caldb version are unchanged, it implies that there was an upgrade of the processing script itself.