Pulse broadening analysis for several new pulsars and anomalous scattering
Pulse broadening analysis for several new pulsars and anomalous scattering
复制标题
几种新型脉冲星的脉冲展宽分析和反常散射
DOI：
10.1093/mnras/stt989
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发表时间：
2013
影响因子：
4.8
通讯作者：
M. Kowalinska
中科院分区：
文献类型：
--
作者：
W. Lewandowski;M. Dembska;J. Kijak;M. Kowalinska
本文给出了利用GMRT和E-100射电望远镜收集的数据对25颗恒星在几个频率上的脉冲展宽现象进行分析的结果。其中有22颗星以前没有在这方面进行过研究，我们的工作使具有多频散射测量的星的总数增加到近50颗，基本上是迄今为止可用数量的两倍。我们观测到的大多数天体都具有高到非常高的色散度量（DM > 200），我们的结果证实了Lo？hmer等人（2001，2004）的建议，即高DM天体的散射时间谱指数偏离了由具有密度涨落的Kolmogorov分布的单个薄屏模型预测的值。在本文中，我们讨论了可能的explanations这种deviation. Keywords：恒星：恒星-一般，恒星-散射1引言存在的电离部分的星际介质（ISM）的影响入射脉冲星辐射在几个方面。第一阶效应--星际色散--是由于自由电子沿着视线的散射，通常用色散度量来量化：DM =R
ABSTRACT We show the results of our analysis of the pulse broadening phenomenon in 25 pulsars at sev-eral frequencies using the data gathered with GMRT and Effelsberg radiotelescopes. Twentytwo of these pulsars were not studied in that regard before and our work has increased thetotal number of pulsars with multi-frequency scattering measurements to almost 50, basi-cally doubling the amount available so far. The majority of the pulsars we observed havehigh to very-high dispersion measures (DM > 200) and our results confirm the suggestion ofLo¨hmer et al. (2001, 2004) that the scatter time spectral indices for high-DM pulsars deviatefrom the value predicted by a single thin screen model with Kolmogorov’s distribution of thedensity fluctuations. In this paper we discuss the possible e xplanations for such deviations.Key words: stars: pulsars – general, pulsars – scattering 1 INTRODUCTIONThe existence of the ionized fraction of the Interstellar Medium(ISM) affects the incoming pulsar radiation in several ways. Thefirst order e ffect - the interstellar dispersion - is due to the amountof the free electrons along the line-of-sight, usually quantized bythe Dispersion Measure: DM =R