13-18 December 2015
International Conference Centre Geneva
Europe/Zurich timezone

Using millisecond pulsars to calibrate XMM/Newton onboard clock

16 Dec 2015, 18:35
Level 0, Room 3 (International Conference Centre Geneva)

Level 0, Room 3

International Conference Centre Geneva

Poster 15 - Binaries


Ms Marilyn Cruces (Instituto de Astrofísica, Pontificia Universidad Católica de Chile)


The XMM-Newton space telescope is capable of 30-microsecond time resolution but its onboard clock drifts, for example due to changes in temperature. Current calibration documentation only provides an upper limit on the clock drift of 10^-8, but observations of X-ray millisecond pulsars (MSPs) suggest that it should be more stable. Using kilo-second XMM-Newton observations of MSPs taken with the EPIC pn-camera in fast timing mode in addition to radio timing measurements from the ATNF pulsar catalog for J1939+2134 (641.9 Hz), J0437-4715 (173.6 Hz), J0218+4232 (430.4 Hz) and J0534+2200 (29.9 Hz), we analyzed the pulse shape for each object with the aim to detect the broadening in the profile produced for a linear clock drift through the use of the statistical H-test plus minimization methods. Our results suggest that the clock is much more stable than what was previously claimed in the literature. A well-established clock stability would permit to derive physical quantities with a properly understood accuracy and perform interesting measurements in accreting X-ray millisecond pulsars (e.g. spin-down rate), transients, among others.

Primary author

Ms Marilyn Cruces (Instituto de Astrofísica, Pontificia Universidad Católica de Chile)


Dr Anne Archibald (ASTRON, Netherlands Institute for Radio Astronomy) Dr Vlad Kondratiev (ASTRON, Netherlands Institute for Radio Astronomy)

Presentation Materials