以澳大利亚国家天文台Parks射电望远镜观测到的12颗毫秒脉冲星共十余年的实测计时数据为基础,首先根据互相关法获取脉冲到达时间及其误差,分析太阳系质心时的计时残差,然后运用傅里叶级数建立综合脉冲星时模型,从而实现地球时,并利用!z方法评估了它的稳定度。结果表明,综合脉冲星时的稳定度呈现线性增强趋势,10a的稳定度高于10^-15。白噪声是主要噪声来源,其对稳定度的影响随着时间的增长逐渐减弱。综合脉冲星时的稳定性和BIPM(2013)相当,可以作为地球时的一种实现方式。
Based on over 10-year timing data for 12 millisecond pulsars from the Parks telescope at Australia Telescope National Facility, TOAs(time of arrival) for these millisecond pulsars and their errors were solved using the cross-correlation technique. The corresponding timing residuals in Bary- centric Coordinate Time were analyzed and then the Ensemble Pulsar Timescale model was constructed using Fourier series in order to realize Terrestrial Time. The stability of the timescale was evaluated with sz method. The results show that the stability of the ensemble Pulsar Timescale reached 10--15 over 10 years, presenting a linear increasing trend with an a upward tendency over time. The stability could rise with a longer observation time. White noise is the primary noise source and its impact on stability of the timescale decreased over time. Ensemble Pulsar Timescale could be considered as a re- alization of Terrestrial Time since the stability of the timescale is comparable to that of BIPM(2013).