脉冲星脉冲宽度的测量方法  

Pulse Width Measurements for Pulsars

作　　者：徐钧[1,2] 韩金林[1] 王陈[1] 

机构地区：[1]中国科学院国家天文台,北京100012 [2]中国科学院研究生院,北京100049

出　　处：《天文学报》2011年第3期180-189,共10页Acta Astronomica Sinica

基　　金：国家自然科学基金项目(10821061和10833003)资助

摘　　要：脉冲宽度的测量方法有几种.最常用的脉冲宽度有W_(pp)(两峰值点的间距)、W_(50)(最高峰值强度50%处的宽度)和W_(10)(最高峰值强度10%处的宽度).另外,还有测量两个最外成分各自强度50%处的宽度W_(c50)和各自强度10%处的宽度W_(c10).利用16颗双锥峰脉冲星和7颗核锥三峰脉冲星样本在1.4 GHz的脉冲轮廓数据,测量了5种脉冲宽度.利用有磁倾角α和撞击角β数据的脉冲星,导出了对应的辐射束半径ρ,并验证其与脉冲星周期P之间的关系ρ∝P^(-0.5).通过比较5种脉冲宽度导出的ρ与P关系的好坏,发现最外成分之间的宽度比前面3种宽度更好,其中W_(c50)宽度得出的相关关系最好.由此认为W_(c50)是最能反映辐射束宽度的测量值.还讨论了脉冲轮廓的对称性,发现后随的锥辐射成分与先导的锥辐射成分相比,更靠近核心辐射成分,两个锥辐射成分的宽度在统计上基本相同.The pulse profile widths of pulsars can be measured as： Wpp （peak-peak separation of two cone components）, W50 （the full width at half of the maximum intensity）, W10 （the full width at 10% of the maximum）, Wc50 （the width between the phases at 50% of the maxima of the two outer components） and Wc10 （the width between the phases at 10% of the maxima the two outer components）. These pulse widths are gotten by using profile data of 16 Conal Double pulsars and 7 Triple pulsars at 1.4 GHz. We derived the beam sizes （ρ） of those pulsars using the measured pulse widths, the magnetic inclination a and impact angle β, and then verified if p follows the relation with the pulsar period （P）, i.e., p ρ∝ p^-0.5. Through comparing the tightness of the correlations between p and P, we found that the pulse widths between the outer components （Wc50, Wc10） are better than the other three widths （Wpp, W50, W10）, and Wc50 is the best. We notice that for the cone-core triple profiles the trailing cone components are closer to the core components than the leading cone ones. The widths of the two cone components of these pulsars are roughly the same statistically.

关 键 词：脉冲星 普通 偏振 恒星 中子 

分 类 号：P145[天文地球—天体物理]