T:Millisecond pulsars have high rotation stability,which can be applied to many research fields,such as the establishment of the pulsar time standard,detection of gravitational wave,spacecraft navigation by using X-ray pulsars and so on.In this paper,we employ two millisecond pulsars PSR J0437-4715 and J1713+0743 which are observed by International Pulsar Timing Array (IPTA),to analyze the precision of pulsar clock parameter and the prediction accuracy of pulse time of arrival (TOA).It is found that the uncertainty of spin frequency is 10-15 Hz,the uncertainty of the first derivative of spin frequency is 10-23 s-2,and the precision of measured rotational parameters increases by one order of magnitude with the accumulated observational data every 4-5 years.In addition,the errors of 4.8 yr TOAs which are predicted by the clock model established by the 10 yr data of J0437-4715 are less than 1 μs.Therefore,one can use the pulsar time standard to calibrate the atomic clock,which can make atomic time deviate from TT (Terrestrial Time) less than 1 μs within 4.8 yr.%毫秒脉冲星具有很高的自转稳定性,利用脉冲星自转极其稳定的特性可以开展许多应用研究,如:脉冲星时间标准的建立、宇宙背景引力波的探测、X射线脉冲星导航应用等等.利用国际脉冲星计时阵(International Pulsar Timing Array,IPTA)中J0437-4715和J1713+0743 2颗源的实测数据开展脉冲星钟模型参数精度分析和脉冲到达时间(Time Of Arrival,TOA)预报精度研究.通过研究得知,目前脉冲星自转频率测量精度为10-15 Hz,频率1阶导数测量精度为10-23 s-2,且自转参数测量精度随观测时间跨度每4-5 yr提高1个量级.另外,利用J0437-4715 10 yr观测数据建立的钟模型,其脉冲到达时间预报偏差4.8 yr之内可保持在1μs之内.因此,利用该脉冲星建立时间标准用于校准原子时,可以使原子时相对于地球时(Terrestrial Time,TT)的偏差在4.8 yr之内小于1 μs.
展开▼
