The Double Pulsar: A Rare Laboratory for Relativistic Gravity and Pulsar Emission Physics

双脉冲星：相对论引力和脉冲星发射物理的罕见实验室

• 批准号: 1517003
• 负责人: Maura McLaughlin
• 金额: $ 20.87万
• 依托单位: West Virginia University Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-15 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1517003&HistoricalAwards=false
• 关键词: Double; Pulsar; Rare; Laboratory; Relativistic

Neutron stars are the compact, highly magnetized remnants of massive stars that have ended their lives in supernova explosions. These stars weigh more than the Sun and yet are only 10 miles across, making them the densest objects next to black holes. Some of these neutron stars are seen as radio pulsars, which emit beams of radio emission detectable by telescopes on Earth as they spin. The rotation periods of pulsars are incredibly stable, allowing them to be used as ultra-precise cosmic clocks for fundamental physics experiments. Roughly 300 of the 2500 known pulsars are in binary systems with other stars, and only 10 of these are in binary systems with other neutron stars. The large masses and short orbital periods of these double neutron star binaries make them remarkable laboratories for fundamental physics, and in particular for testing Einstein's theory of general relativity. One of these double neutron star binaries is truly exceptional, as it is the only one in which both of the neutron stars are detectable as radio pulsars. This makes the tests of general relativity more precise than for any other system and provides the best test ever of general relativity in the so-called strong-field regime. We also observe interactions between the two pulsars which can be used to help understand pulsar emission physics. This proposal will fund analysis of high-precision data taken with the Green Bank Telescope in Green Bank, WV, that will provide even better tests of general relativity and provide crucial information about the emission mechanisms and geometries of the two pulsars in the system. The information gleaned from the observations of this system is truly unique and the goals could not be achieved through any other means.While the investigators are focused on one system, the implications of the work are vast. The techniques they develop will be crucial for future double pulsar systems sure to be discovered through upcoming wide-field pulsar surveys. They will also develop an animation which will be of interest to the general public, students, and scientists. This animation will show how the pulse profile of B varies with time due to geodetic precession and the changing influence of pulsar A. These animations will be hosted on a website which will include other educational materials on the Double Pulsar, pulsar properties, general relativity, and gravitational wavesGeneral relativity (GR) is the most elegant and complete description of gravity ever produced. The investigators will make more sensitive GR tests, including the elimination of alternative theories of gravity and, possibly, the measurement of second-order Post-Keplerian corrections to lead to the first measurement of a NS moment of inertia. This would provide a unique constraint on the NS equation of state. This work will also lead to measurement of fundamental properties of the system that will inform understanding of binary evolution, pulsar emission physics, and detection rates for ground-based interferometers that cannot be measured in any other way. It will also provide crucial input for gravitational wave detectors, facilitating one of the most important scientific milestones of the decade.

中子星是在超新星爆炸中结束生命的大质量恒星的致密、高度磁化的残骸。这些恒星比太阳还重，但直径只有10英里，这使它们成为黑洞附近密度最大的物体。其中一些中子星被视为射电脉冲星，当它们旋转时，地球上的望远镜可以探测到它们发出的射电辐射束。脉冲星的旋转周期非常稳定，这使得它们可以用作基础物理实验的超精确宇宙时钟。在已知的2500颗脉冲星中，大约有300颗与其他恒星在双星系统中，其中只有10颗与其他中子星在双星系统中。这些双中子星的大质量和短轨道周期使它们成为基础物理学的卓越实验室，特别是用于测试爱因斯坦的广义相对论。这些双中子星双星中的一个是真正的例外，因为它是唯一一个两个中子星都是射电脉冲星的。这使得广义相对论的测试比任何其他系统的测试都更加精确，并在所谓的强场体系中提供了迄今为止最好的广义相对论测试。我们还观察到两颗脉冲星之间的相互作用，这可以用来帮助理解脉冲星发射物理。该提案将资助对WV Green Bank望远镜采集的高精度数据的分析，这将为广义相对论提供更好的测试，并提供有关系统中两颗脉冲星的发射机制和几何形状的关键信息。从这个系统的观察中收集到的信息是真正独特的，通过任何其他手段都无法实现这些目标。虽然研究人员专注于一个系统，但这项工作的影响是巨大的。他们开发的技术将对未来的双脉冲星系统至关重要，这些系统肯定会通过即将到来的宽视场脉冲星调查被发现。他们还将制作一部公众、学生和科学家感兴趣的动画。这个动画将展示B的脉冲轮廓是如何随着时间的变化而变化的，这是由于大地进动和脉冲星a的变化影响。这些动画将被放在一个网站上，该网站将包括其他关于双脉冲星、脉冲星特性、广义相对论和引力波的教育材料。广义相对论（GR）是迄今为止对重力最优雅、最完整的描述。研究人员将进行更灵敏的GR测试，包括消除引力的替代理论，并可能测量二阶后开普勒修正，从而首次测量NS转动惯量。这将为NS状态方程提供一个独特的约束。这项工作还将导致测量系统的基本特性，这将有助于了解双星演化，脉冲星发射物理，以及地基干涉仪的检测率，这些都是无法用任何其他方式测量的。它还将为引力波探测器提供关键的输入，促进十年来最重要的科学里程碑之一。