Searching for Pulsations in the Millisecond Pulsar PSRJ1231-1411

We propose to observe the Fermi/LAT millisecond rotation-powered pulsar (MSP) PSR J1231-1411 in EPIC-pn Timing Mode for 100 ks. PSR J1231-1411 is one of a growing number of rotation-powered MSPs discovered by searching unassociated sources from the Fermi/LAT at radio wavelengths. A previous XMM-Newton observation revealed a neutron star X-ray source spatially coincident with the radio position but is not adequate for the pulsation search we propose here. We will search for X-ray pulsations and utilize the pulsation light curve to constrain the geometry of the polar cap magnetic field and the compactness of the neutron star. We will use the MOS spectroscopic data to constrain the effective temperature and effective emitting area of the neutron star.