Does the accreting millisecond pulsar XTE J1814-338 precess?
CTY Chung, DK Galloway, A Melatos
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | OXFORD UNIV PRESS | Published : 2008
Precession in an accretion-powered pulsar is expected to produce characteristic variations in the pulse properties. Assuming surface intensity maps with one and two hotspots, we compute theoretically the periodic modulation of the mean flux, pulse-phase residuals and fractional amplitudes of the first and second harmonic of the pulse profiles. These quantities are characterized in terms of their relative precession phase offsets. We then search for these signatures in 37 d of X-ray timing data from the accreting millisecond pulsar XTE J1814-338. We analyse a 12.2-d modulation observed previously and show that it is consistent with a freely precessing neutron star only if the inclination angl..View full abstract
We are grateful to Ranjan Singh for carrying out preliminary investigations of the precession model described in the manuscript. CC acknowledges the support of an Australian Postgraduate Award.