Prompt XMM-Newton and NuSTAR study of magnetar outbursts

Magnetars are a small class of neutron stars mainly powered by their hugemagnetic fields. They go through long stretches of quiescence, interrupted byperiods of activity, via large flares and yearlytimescale Xray outbursts.Magnetar activity has been recently observed also in other pulsar classes.Observations performed during, and immediately after such periods yield thelargest amount of information on this magnetic emission, allowing one to testthe theoretical models on a variety of phenomena and source states. We propose aJoint XMM (85ks) and NuSTAR (170ks) ToO program (1 trigger of 4 observationsover a few months) aimed at gathering new physical insight on the crust andfield configuration of sources showing magnetar outbursts. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]