A neutron star with a carbon atmosphere in the Cassiopeia A supernova remnant

被引：206

作者：

Ho, Wynn C. G. ^{[1
]}

Heinke, Craig O. ^{[2
]}

机构：

[1] Univ Southampton, Sch Math, Southampton SO17 1BJ, Hants, England

[2] Univ Alberta, Dept Phys, Edmonton, AB T6G 2G7, Canada

来源：

NATURE | 2009年 / 462卷 / 7269期

基金：

英国科学技术设施理事会; 加拿大自然科学与工程研究理事会;

关键词：

EVOLUTION; HYDROGEN; OBJECT;

D O I：

10.1038/nature08525

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

The surface of hot neutron stars is covered by a thin atmosphere. If there is accretion after neutron-star formation, the atmosphere could be composed of light elements (H or He); if no accretion takes place or if thermonuclear reactions occur after accretion, heavy elements (for example, Fe) are expected. Despite detailed searches, observations have been unable to confirm the atmospheric composition of isolated neutron stars(1). Here we report an analysis of archival observations of the compact X-ray source in the centre of the Cassiopeia A supernova remnant. We show that a carbon atmosphere neutron star (with low magnetic field) produces a good fit to the spectrum. Our emission model, in contrast with others(2-4), implies an emission size consistent with theoretical predictions for the radius of neutron stars. This result suggests that there is nuclear burning in the surface layers(5,6) and also identifies the compact source as a very young (similar to 330-year-old) neutron star.

引用

页码：71 / 73

页数：3

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