Abstract for Proposal 096158

The First Five Days: The Onset of Nuclear Burning in SAX J1808.4-3568

We propose an optically triggered, nearly continuous monitoring campaign of the first five days of an outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3568 with XMM-Newton. Key goals for this unique campaign are to observe the accretion onset and the low accretion rate nuclear burning regime where weak, hydrogen triggered X-ray bursts are expected. Observational evidence for this regime has only recently been presented, but X-ray coverage of the onset of outbursts remains exceedingly rare, and even when observed have been done so with very low duty cycle. XMM-Newton provides the critical, nearly continuous observations needed to measure burst recurrence times and to fully account for the energy associated with accretion, and both stable and unstable CNO hydrogen burning.

Details on Observing Strategy and Trigger Criteria
There are no triggering criteria available for this proposal yet.