论文标题
螃蟹脉冲星的单脉冲分散度量
Single Pulse Dispersion Measure of the Crab Pulsar
论文作者
论文摘要
我们研究了从螃蟹脉冲星中明亮的单个脉冲的使用，以分别确定主脉冲和插入组件的色散度量（DM）。我们使用跨相关函数（CCF）开发了两种方法。第一种方法使用参考通道计算64个频道中每种频道的总强度的CCF，并将最大相关性的时间滞后转换为DM。第二种方法分别计算每个单独的明亮脉冲之间的每对通道之间的CCF，并从所有通道对DMS的分布中提取平均DM。两种方法都允许确定DM的相对不确定性高于10^-5，并为最佳拟合值的不确定性提供了可靠的估计。我们发现，使用这两种方法在4到6 GHz的频率范围内使用这两种方法，主脉冲，低频插入和高频插孔之间的DM差异。早期观察到Hankins等人进行的高频插孔。 （2016）导致DM_HFIP-DM_MP为0.010 +-0.016 PC CM^-3。我们的结果表明，DM_HFIP-DM_MP为0.0127 +-0.0011 PC CM^-3（DM_COMP是相应发射组件的DM值），通过独立方法证实了早期结果。在我们的研究中，我们还发现高频插入中单个脉冲的亮度与其DM之间的关系。我们还讨论了开发方法在快速无线电爆发的情况下识别子结构的应用。
We investigate the use of bright single pulses from the Crab pulsar to determine separately the dispersion measure (DM) for the Main Pulse and Interpulse components. We develop two approaches using cross correlation functions (CCFs). The first method computes the CCF of the total intensity of each of 64 frequency channels with a reference channel and converts the time lag of maximum correlation into a DM. The second method separately computes the CCF between every pair of channels for each individual bright pulse and extracts an average DM from the distribution of all channel-pair DMs. Both methods allow the determination of the DM with a relative uncertainty of better than 10^-5 and provide robust estimates for the uncertainty of the best-fit value. We find differences in DM between the Main Pulse, the Low Frequency Interpulse, and the High Frequency Interpulse using both methods in a frequency range from 4 to 6 GHz. Earlier observations of the High Frequency Interpulse carried out by Hankins et al. (2016) resulted in DM_HFIP-DM_MP of 0.010 +- 0.016 pc cm^-3. Our results indicate a DM_HFIP-DM_MP of 0.0127 +- 0.0011 pc cm^-3 (with DM_comp being the DM value of the respective emission component), confirming earlier results with an independent method. During our studies we also find a relation between the brightness of single pulses in the High Frequency Interpulse and their DM. We also discuss the application of the developed methods on the identification of substructures in the case of Fast Radio Bursts.
