Measuring clock jumps using pulsar timing  

作　　者：ZhiXuan Li KeJia Lee Ricardo Nicolaos Caballero YongHua Xu LongFei Hao Min Wang JianCheng Wang 

机构地区：[1]Yunnan Observatories,Chinese Academy of Sciences,Kunming 650216,China [2]Kavli Institute for Astronomy and Astrophysics,Peking University,Beijing 100871,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Key Laboratory for the Structure and Evolution of Celestial Objects,Chinese Academy of Sciences,Kunming 650216,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2020年第1期112-117,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB23010200);the National Natural Science Foundation of China(Grant Nos.U15311243,and 11690024);the National Basic Research Program of China(Grant No.2015CB857101);the funding from Tian Shan Chuang Xin Tuan Dui and the Max-Planck Partner Group

摘　　要：In this paper,we investigate the statistical signal-processing algorithm to measure the instant local clock jump from the timing data of multiple pulsars.Our algorithm is based on the framework of Bayesian statistics.In order to make the Bayesian algorithm applicable with limited computational resources,we dedicated our efforts to the analytic marginalization of irrelevant parameters.We found that the widely used parameter for pulsar timing systematics,the"Efac"parameter,can be analytically marginalized.This reduces the Gaussian likelihood to a function very similar to the Student’s t-distribution.Our iterative method to solve the maximum likelihood estimator is also explained in the paper.Using pulsar timing data from the Yunnan Kunming 40-m radio telescope,we demonstrate the application of the method,where 80-ns level precision for the clock jump can be achieved.Such a precision is comparable to that of current commercial time transferring service using satellites.We expect that the current method could help developing the autonomous pulsar time scale.In this paper, we investigate the statistical signal-processing algorithm to measure the instant local clock jump from the timing data of multiple pulsars. Our algorithm is based on the framework of Bayesian statistics. In order to make the Bayesian algorithm applicable with limited computational resources, we dedicated our efforts to the analytic marginalization of irrelevant parameters.We found that the widely used parameter for pulsar timing systematics, the "Efac" parameter, can be analytically marginalized.This reduces the Gaussian likelihood to a function very similar to the Student’s t-distribution. Our iterative method to solve the maximum likelihood estimator is also explained in the paper. Using pulsar timing data from the Yunnan Kunming 40-m radio telescope, we demonstrate the application of the method, where 80-ns level precision for the clock jump can be achieved. Such a precision is comparable to that of current commercial time transferring service using satellites. We expect that the current method could help developing the autonomous pulsar time scale.

关 键 词：PULSARS time series analysis clocks and frequency standards 

分 类 号：P145.6[天文地球—天体物理]