New Timing Results of MSPs from NICER Observations

Shijie Zheng; Dawei Han; Heng Xu; Kejia Lee; Jianping Yuan; Haoxi Wang; Mingyu Ge; Liang Zhang; Yongye Li; Yitao Yin; Xiang Ma; Yong Chen; Shuangnan Zhang

arXiv · 2404.16263

New Timing Results of MSPs from NICER Observations

Shijie Zheng·Dawei Han·Heng Xu·Kejia Lee·Jianping Yuan·Haoxi Wang·Mingyu Ge·Liang Zhang·Yongye Li·Yitao Yin·Xiang Ma·Yong Chen·Shuangnan Zhang

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Abstract

Millisecond pulsars (MSPs) are known for their long-term stability. Using six years of observations from the Neutron Star Interior Composition Explorer (NICER), we have conducted an in-depth analysis of the X-ray timing results for six MSPs: PSRs B1937+21, B1821$-$24, J0437$-$4715, J0030+0451, J0218+4232, and J2124$-$3358. The timing stability parameter $\sigma_z$ has been calculated, revealing remarkable timing precision on the order of $10^{-14}$ for PSRs B1937+21 and J0437$-$4715, and $10^{-13}$ for PSRs B1821$-$24, J0218+4232, and J0030+0451 over a timescale of 1000 days. These findings underscore the feasibility of autonomous in-orbit timekeeping using X-ray observations of MSPs. In addition, the consistency of long-term spin-down noise in the X-ray and radio bands has been investigated by comparison with IPTA radio data.

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Shijie Zheng, Dawei Han, Heng Xu, Kejia Lee, Jianping Yuan, Haoxi Wang, Mingyu Ge, Liang Zhang, Yongye Li, Yitao Yin, Xiang Ma, Yong Chen, Shuangnan Zhang. 2024-04-25. New Timing Results of MSPs from NICER Observations. https://arxiv.org/abs/2404.16263

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