Probing the Warped Inner Accretion Flow in SMC X-1 with XMM and NuSTAR

We propose for a series of four 20 ks observations with XMM and NuSTAR of thebinary Xray pulsar SMC X1. This source shows a longperiod (40 60 d)superorbital cycle due to a warped, precessing accretion disk. This disk isheated by the pulsed hard Xray beam from the neutron star, and observations ofthis thermal emission can provide a unique probe of the inner accretion flownear the magnetosphere. However this requires sensitivity and timing resolutionacross the full Xray band (from below 1 keV to above 20 keV), and sampling of afull superorbital cycle. We will take advantage of XMM.s excellent sensitivityand time resolution along with NuSTAR.s exquisite highenergy coverage to yieldthe clearest picture to date of the inner accretion flow. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]