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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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明亮的双中子恒星合并的不对称质量比
R D Ferdman1, P C C Freire2, B B P Perera3
1Faculty of Science, University of East Anglia, Norwich, UK. r.ferdman@uea.ac.uk.
Nature
|July 10, 2020
概括
研究人员发现了迄今为止最不对称的双中子星系统PSR J1913+1102. 这一发现表明不对称的二进制星体可能会解释引力波事件的异常千诺瓦辐射,如GW170817.
科学领域:
- 天体物理学与天文学
- 引力波天文学
- 中子星物理学
背景情况:
- 双质中子星合并GW170817是引力波事件的唯一确定的电磁对应.
- 从GW170817的晚期电磁辐射不符合标准的中子星融合模型.
- 我们银河系中已知融合的双中子星系主要是几乎相同质量的二进制星系.
研究的目的:
- 为了研究脉冲星PSR J1913+1102及其伴侣中子星的特性.
- 为了确定这个双中子恒星系统的质量比.
- 评估不对称的二进制群体对理解GW170817的影响.
主要方法:
- 进行了专门的脉冲星计时活动,以精确测量PSR J1913+1102及其同伴的质量.
- 分析了轨道参数,包括离心率和分离,以推断合并时间表.
- 根据发现的不对称二进制系统进行了人口合成分析.
主要成果:
- 测量了脉冲星和伴侣中子星的质量,分别为1.62±0.03和1.27±0.03太阳质量.
- 确定了0.78±0.03的质量比,确定它是迄今为止发现的最不对称的合并系统.
- 种群综合表明不对称的二进制构成所有合并的二进制种群的2-30%.
结论:
- 发现高度不对称的PSR J1913+1102系统为GW170817提供了潜在的祖先.
- 不对称的中子星合并可以解释从GW170817观察到的异常千诺瓦辐射.
- 这一发现扩大了我们对二进制中子星群体的多样性的理解.
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