1. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 1 XMM-Newton Status of EPIC time jump problems Marcus G. F. Kirsch, M.J. Freyberg, E. Kendziorra, U. Lammers

2. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 2 XMM-Newton EPIC Time jumps mid-2000 first discovered pn-AUX data anomalies: –frequency of occurrence is variable –unrelated to camera mode, observing time or duration –some data sets are completely free of any problems others are heavily affected. reason: H/W problem of EPEA consequences: event times turn out wrong –single shift in FTCOARSE time will cause all subsequent times to be wrongly shifted by the same amount. –pulse profile analyses inconclusive because all photons after the instant of the time jump will be out-of-phase –pulse peak broadening, phase shift or the appearance of spurious pulse components. SAS should find and correct those time jumps

3. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 3 XMM-Newton EPIC Situation 5.4.1 Not all negative or positive jumps in FTCOARSE are found and corrected by SAS pulse peak broadening, phase shift spurious pulse components

4. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 4 XMM-Newton EPIC Experimenting with the detection algorithm:  2 -tests 0153750301 0153750401 0153750501 deltrack 6.0

5. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 5 XMM-Newton EPIC Relative Timing accuracy

6. Marcus Kirsch Science Operations & Data Systems Division Research & Scientific Support Department Page 6 XMM-Newton EPIC Status: SAS 6.0 fast modes: –problems are reliably found and corrected –only 2 know problem cases imaging modes: –rare cases of very long time jumps (ks) in the imaging modes (< 0.5 %) –still uncorrected time gaps with no integer multiple of frame time (< 2 %) mainly in revs < 220 list of problematical cases and work around will be provided in document: XMM-Newton EPIC photon arrival times: This document gives an overview of the readout of the EPIC camera and the applied correction to the photon arrival times. list of problematical cases and work around will be provided in document: XMM-Newton EPIC photon arrival times: This document gives an overview of the readout of the EPIC camera and the applied correction to the photon arrival times.