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arXiv 1906.06992astro-ph.HEastro-ph.SR
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中年人定时噪声的诊断

Diagnostics of timing noise in middle aged pulsars

Nakornping Namkham, Phrudth Jaroenjittichai, Simon Johnston

摘要:

在各种各样的实验中,射电望远镜经常被用作时钟。时钟中的缺陷,称为定时噪声,有可能降低其重要性,甚至阻碍例如寻找随机引力波(GW)背景的尝试。自2014年以来,利用Parkes射电望远镜观测了129颗中年恒星(特征年龄在100万年左右)的时间噪声。我们研究了四种不同的定时噪声指标,但仍不清楚哪一种(如果有的话)提供了最佳的确定。尽管如此,很明显,这些微扰星的定时噪声比它们年轻的同行要小得多,但比(老得多的)毫秒微扰星(MSP)要大得多。与以前的作者一样,我们发现定时噪声和脉冲星自旋下降率,$\dotν$之间有很强的相关性。然而,对于一个给定的$\dotν$,定时噪声的强度大约有30倍的扩展,这可能表明恒星内部的核条件在物体之间是不同的。我们简要地评论GW检测脉冲星定时阵列的定时噪声水平可能小于预测的影响。

英文摘要:

Radio pulsars are often used as clocks in a wide variety of experiments. Imperfections in the clock, known as timing noise, have the potential to reduce the significance of, or even thwart e.g. the attempt to find a stochastic gravitational wave (GW) background. We measure the timing noise in a group of 129 mostly middle-aged pulsars (i.e. characterstic ages near 1~Myr) observed with the Parkes radio telescope on a monthly basis since 2014. We examine four different metrics for timing noise, but it remains unclear which, if any, provides the best determination. In spite of this, it is evident that these pulsars have significantly less timing noise than their younger counterparts, but significantly more than the (much older) millisecond pulsars (MSPs). As with previous authors, we find a strong correlation between timing noise and the pulsar spin-down rate, $\dotν$. However, for a given $\dotν$ there is a spread of about a factor 30 in the strength of the timing noise likely indicating that nuclear conditions in the interior of the stars differs between objects. We briefly comment on the implications for GW detection through pulsar timing arrays as the level of timing noise in MSPs may be less than predicted.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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