采用Shapiro延迟测量的一颗2太阳质量的中子星
P B Demorest1, T Pennucci, S M Ransom
1National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, Virginia 22093, USA. pdemores@nrao.edu
Nature
|October 29, 2010
概括
中子星含有宇宙中最密集的物质. 发现了一颗巨大的中子星,质量是太阳质量的1.97倍,排除了外来物质理论,并建议强烈相互作用的夸克.
科学领域:
- * 天体物理学 * 天体物理学
- * 核物理 核物理
- * * 一般相对论
背景情况:
- * 中子星代表了最密集的可观测物质,其组成和特性不确定.
- *测量中子星质量和半径对于限制状态方程和测试理论模型至关重要.
- *以前的质量测量不足以排除外来物质组成.
研究的目的:
- *使用沙皮罗延迟精确测量中子星的质量.
- * 为了限制中子星内的物质状态方程.
- * 测试中子星组成的理论模型,包括外来物质候选物.
主要方法:
- *利用了对二进制毫秒脉冲星J1614-2230.0的无线电计时观测.
- *分析了沙皮罗延迟特征,这是由时空曲率引起的广义相对论效应.
- * 推断了中子星及其双星伴侣的质量,并且非常精确.
主要成果:
- *确定J1614-2230中子星的质量为1.97±0.04太阳质量.
- * 这种质量测量排除了几乎所有涉及超子或玻色子凝聚物的状态方程.
- *这些发现暗示,如果夸克物质存在于如此巨大的恒星中,那么夸克必须有强烈的相互作用.
结论:
- *发现一个巨大的中子星挑战了关于超密度物质组成的现有理论.
- *结果强烈反对使用异国情调,非核子物质成分的模型,如超子或玻色子凝聚物.
- *数据表明,如果存在夸克物质,必须表现出强烈的相互作用,排除自由夸克状态.
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