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Updated: May 29, 2026

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Genomic Transformation of the Picoeukaryote Ostreococcus tauri
Published on: July 13, 2012
一颗恒星在毫秒内转变为一颗行星 脉冲星 双星
M Bailes1, S D Bates, V Bhalerao
1Centre for Astrophysics and Supercomputing and ARC Centre for All-Sky Astrophysics (CAASTRO), Swinburne University of Technology, Post Office Box 218 Hawthorn, VIC 3122, Australia. mbailes@swin.edu.au
概括
研究人员发现一个单独的毫秒脉冲星,PSR J1719-1438,实际上是在一个二进制系统. 它的伴侣可能是一个超低质量的碳白矮星,为脉冲星起源提供线索.
科学领域:
- 天文学和天体物理学
- 紧的对象 紧的对象
- 中子星是什么意思 中子星是什么意思
背景情况:
- 毫秒脉冲星 (MSP) 是快速旋转的中子星,通常在二进制星系中发现,在那里积累会使它们旋转.
- 很大一部分 (约30%) 的MSP是孤独的,这对标准的形成模式构成了挑战.
- 了解孤独的MSP的起源对于了解恒星演变的完整画面至关重要.
研究的目的:
- 为了研究孤独的毫秒脉冲星PSR J1719-1438.8的性质和起源.
- 为了确定PSR J1719-1438是否真正是孤独的或是二进制系统的一部分.
- 描述伴随物体及其对脉冲星演变的影响.
主要方法:
- 使用来自帕克斯64米射电望远镜调查的数据.
- 执行脉冲星信号的时间分析,以检测轨道变化.
- 根据轨道参数计算伴侣物体的质量和密度.
主要成果:
- 毫秒脉冲星PSR J1719-1438在一个轨道周期为2.2小时的二进制星系中被探测到.
- 伴侣的质量与木星的质量相当.
- 伴侣的高密度 (最低23g/cm3) 表明它是一个超低质量的碳白矮星.
结论:
- 这一发现挑战了一些MSP的孤独性质,并为二进制形成途径提供了证据.
- 伴侣的属性表明,它过去是一个超紧的低质量X射线双星.
- 这个系统提供了对二进制恒星的极端进化和伴侣在积累阶段的生存的见解.
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