Parkes observations for project P880 semester 2016OCTS

XSS J1227-4859 is the second "Transitional" pulsar binary system discovered in the galactic field. We plan to continue our campaign of observations at 20cm with the aims of: (i) discriminating the various proposed mechanisms responsible for the orbital variations seen in the system; (ii) keeping the phase coherence of the timing solution in order to investigate the nature of the gamma-ray emission from the binary; (iii) determining the critical X-ray luminosity above which the pulsed radio emission disappears; (iv) constraining the geometry of the emission from the system in the radio, X-ray and gamma-ray bands through (quasi) simultaneous multiwavelength observations..