We noticed a peculiar feature in the time-stamp synchronization monitor. The spectra of timestamp difference between pairs of DAQ systems show, for all possible pair combinations, a peak at Delta(ts)= 65535 = 2**15

This corresponds to a difference of 2.6 ms (for 25MHz correlation clock). See the attachments taken ~23:00 of Nov 28th.

We performed the AIDA system-wide checks (no errors) and a timestamp reset, but the second peak at 65K is still there (we also checked that there is no peak at 2*65K, at least in a short run period).

We also observed a double peak for timestam-differences close to zero, which we interpret as good correlations (attachment 2). Note, however, that this double peak became much supprese around midnight (see attachment 6 and 7).

From analysis of ion (BigRIPS) and implant (AIDA) correlations we have some confidence that these two DAQs are synchronized; see entry https://elog.ph.ed.ac.uk/AIDA/492 where we identify an implant for 20% ofions at F11 (and with an implantatin profile that, for example, is consistent with changes to the degrader configuration)