Research On Millisecond Pulsars' Time Scale And Clock Model

The pulsar is a kind of neutron stars with high-speed rotation, the rotation period of them are extremely stable , especially the millisecond pulsars, which is the natural frequency source that can be comparable to the quantum frequency standard, is the natural clock without maintenance, is excepted to calibrate the ground atomic time system. The inherent internal disturbance of millisecond pulsar is very small, they rotate very stable, the measurement of millisecond pulsar's pulse arrives time has become the most important observation, which provide the feasibility of establishing the time standards with pulsars.This paper summarizes the basic attributes of pulsars, the pulsar timing observation process is briefly discussed, the research on millisecond pulsar time scale ,pulsar clock model and ensemble pulsar time are emphasized, the results show that the millisecond pulsar are more suitable for the timing and navigation applications than ordinary pulsars. The radio pulse signals of the pulsar Geminga, observed at Pushchino radio astronomy observatory in low frequency, has been analyzed and compared with previous results. The de-noising process with Tempo2 before the fitting of residuals is briefly introduced, also with the fitting and analysis methods. Through the simulation result, this approach's influence on the establishing of standard pulsar time scale is analyzed. Researched the method of establishing pulsars clock model, predicted the J1857 + 0943's pulse phase and rotation frequency during 12 h with the latest predicted software Polyco, the latest plug-in of Tempo2, and made each extensive subsection's prediction during the start-stop time of latest calendar table's effective epoch, discussed the accuracy of the prediction, verified the drift of millisecond pulsars'rotation frequency, and made the error analysis.Firstly calculated the ensemble pulsar time with more than 2 pulsars'ten years measured data observed at PARKES. Evaluated the stability of them, and compared their stability with related atomic time scale, discussed multiple modified approaches, also with the application merits and the significance of millisecond pulsar time scale.