Crust cooling of the neutron star in 1RXS J180408.9 342058

We propose a 70 ks XMMNewton observation of the neutron star in 1RXSJ180408.9342058 (1RXS J1804), a transient LMXB which underwent a virgul4.5 monthaccretion outburst in 2015. The neutron star in transient LMXBs may experiencecrust heating during the outburst and subsequent cooling in quiescence. Trackingthe thermal evolution of the crust over time helps indicate the properties ofneutron star matter. 1RXS J1804 has already been monitored for virgul480 days intoquiescence and observations have indicated crust cooling. By observing thesource further in quiescence more constraints on the neutron star crust physicscan be obtained, in particular at deeper layers in the crust than currentlypossible for this source. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]