Parkes observations for project P880 semester 2016OCTS_BPSR_01

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..

XSS J1227-4859是在银道场区中发现的第二个"过渡态"脉冲星双星系统（Transitional pulsar binary system）。我们计划继续开展20厘米波段的观测项目，旨在达成以下目标：(i) 甄别导致该系统轨道变化的各类已提出的物理机制；(ii) 维持计时解的相位相干性，以研究该双星系统的伽马射线辐射本质；(iii) 确定脉冲射电辐射消失的临界X射线光度；(iv) 通过（准）同时多波段观测，约束该系统在射电、X射线与伽马射线波段的辐射几何结构。