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

中子星是大质量恒星在超新星爆炸中结束生命的致密、高度磁化的残余物。这些恒星的重量超过太阳，但直径只有10英里，使它们成为仅次于黑洞的致密物体。这些中子星中的一些被视为射电望远镜，当它们旋转时，它们发出的无线电波束可以被地球上的望远镜探测到。恒星的旋转周期非常稳定，使它们能够被用作基础物理实验的超精确宇宙钟。 在2500颗已知的中子星中，大约有300颗与其他恒星组成双星系统，其中只有10颗与其他中子星组成双星系统。这些双中子星星双星的巨大质量和短的轨道周期使它们成为基础物理学的卓越实验室，特别是检验爱因斯坦的广义相对论。其中一个双中子星星双星是真正的例外，因为它是唯一一个两颗中子星都可以被探测到的射电双星。这使得广义相对论的检验比任何其他系统都更精确，并在所谓的强场区域提供了广义相对论有史以来最好的检验。我们还观察到两个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。这项提议将资助对西弗吉尼亚州绿色银行的绿色银行望远镜拍摄的高精度数据进行分析，这将提供更好的广义相对论测试，并提供有关系统中两个恒星的发射机制和几何形状的关键信息。通过对这一系统的观察收集到的信息确实是独一无二的，这些目标是通过任何其他手段都无法实现的。虽然调查人员专注于一个系统，但这项工作的影响是巨大的。他们开发的技术对于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场脉冲星调查发现。 他们还将开发一个动画，这将是感兴趣的一般公众，学生和科学家。 此动画将显示B的脉冲轮廓如何因大地岁差和脉冲星A的影响而随时间变化。这些动画将被托管在一个网站上，其中将包括其他教育材料的双脉冲星，脉冲星的属性，广义相对论，引力波广义相对论（GR）是最优雅和完整的描述引力有史以来产生。研究人员将进行更敏感的GR测试，包括消除其他引力理论，并可能测量二阶后开普勒修正，以首次测量NS惯性矩。 这将对NS状态方程提供唯一的约束。这项工作还将导致测量系统的基本特性，这将有助于理解双星演化，脉冲星发射物理学和无法以任何其他方式测量的地面干涉仪的检测率。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。

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.