Pre-planned ToO of a pre-main sequence star undergoing an optical-IR outburst

Dramatic optical/IR outbursts from PMS stars, which signal the onset of rapidmassinfall onto such stars through their accretion disks, cannot be predicted.However, our Chandra and XMM monitoring of the outburst of V1647 Oridemonstrates that a high accretion rate can also produce an Xray outburst, and,indeed, that Xray monitoring of PMS accretion outbursts represents a newobservational window on the magnetic interaction between the stellarmagnetosphere and the accretion disk. We propose a 80 ksexposure XMM ToO of anyXray outburst, confirmed with Chandra or Swift (short) ToO exposure, to performXray spectroscopy with EPIC and to investigate Xray variability on a timescaleof a day. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]