The Einstein@Home search for new neutron stars

Einstein@Home是一个志愿者分布式计算项目。空闲时，家用电脑从Einstein@Home服务器下载天文数据，搜索微弱信号，并上传结果。Einstein@Home的目标是利用先进的LIGO和处女座天文台的引力波数据、费米卫星的伽马射线数据以及阿雷西博天文台和其他射电望远镜的无线电数据，发现新的中子星。中子星，这个搜索的目标，是在超新星爆炸中形成的极端物体。虽然它们的直径只有大约10英里，但它们的质量却比太阳大。到目前为止，大多数中子星都是通过脉冲被发现的，这种脉冲是当它们的电磁辐射有规律地扫过地球时发生的。然而，尽管人们相信银河系包含大约1亿颗中子星，但迄今为止发现的中子星还不到3000颗。引力波很可能是揭开这些看不见的极端天体群的唯一方法。威斯康星大学密尔沃基分校（University of Wisconsin at Milwaukee）开展的一个项目有三个目标：利用Einstein@Home(1)首次直接探测到来自旋转中子星的引力波，从而通过一种完全不同的物理机制来观察这些恒星，这将携带有关其内部结构和组成的重要新信息。(2)利用南非MeerKAT望远镜阵列的新高频射电数据，发现银河系中心附近的中子星。这将为该团体提供一种研究超大质量黑洞的方法，以及它周围密集和活跃的区域。(3)利用伽玛射线数据识别无线电静默毫秒伽玛射线脉冲星，为脉冲星的演化和发射提供新的证据。Einstein@Home是一个杰出的公共推广工作，允许世界各地的人们直接为令人兴奋的前沿科学研究做出贡献。自项目启动以来，Einstein@Home志愿者已经为该项目贡献了超过30亿cpu核小时的计算时间。使用典型的成本计算（像亚马逊这样的云提供商，或者超级计算中心），这代表了超过1亿美元的计算时间。该合同还为Einstein@Home的持续运营和进一步发展提供资金，包括中央硬件和软件基础设施的维护和管理，LIGO、Virgo、Fermi和无线电数据的处理和后处理，以及改进搜索方法的设计和实现。对连续引力波的探测将使我们得以一窥居住在银河系中不可见的中子星种群，并揭示它们的内部结构和进化历史。在短周期双星和银河系中心附近发现新的中子星将提高我们对恒星演化和种群的理解，有助于研究银河系中心的黑洞，并为广义相对论提供严格的检验。新的毫秒射电脉冲星的发现将提高“脉冲星定时阵列”探测低频引力波的能力。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Einstein@Home is a volunteer distributed computing project. When otherwise idle, home computers download astronomical data from the Einstein@Home servers, search it for weak signals, and upload the results. The aim of Einstein@Home is to discover new neutron stars, using gravitational wave data from the advanced LIGO and Virgo observatories, gamma-ray data from the Fermi Satellite, and radio data from the Arecibo Observatory and other radio telescopes. Neutron stars, the targets of this search, are extreme objects formed in supernova explosions. Although they are only about ten miles in diameter, they are more massive than the Sun. So far, most neutron stars have been discovered via pulsations that occur when their beamed electromagnetic emission regularly sweeps past the earth. However, while it is believed that the Milky Way contains about a hundred million neutron stars, fewer than 3000 have been detected so far. Gravitational waves might well be the only way to unveil this invisible population of extreme objects. A project run by the University of Wisconsin at Milwaukee has three goals to use Einstein@Home to (1) Make the first direct detection of gravitational waves from spinning neutron stars, and thus to observe these stars via a completely different physical mechanism, which would carry important new information about their internal structure and composition. (2) Make use of new high-frequency radio data from the MeerKAT telescope array in South Africa to discover neutron stars near the Galactic center. These would give the community a way to study the supermassive black hole that resides there, as well as the dense and active region around it. (3) Use gamma-ray data to identify radio-quiet millisecond gamma-ray pulsars, providing new evidence about the evolution and emission of pulsars. Einstein@Home is an outstanding public outreach effort, allowing people world-wide to contribute directly to exciting and cutting-edge scientific research.Since it began, Einstein@Home volunteers have donated more than 3 billion CPU-core hours of computing time to the project. Using typical costing (cloud providers like Amazon, or super-computing centers) this represents more than 100 million dollars of computing time. This award also funds the continued operations and further development of Einstein@Home, including maintenance and administration of the central hardware and software infrastructure, the handling and post-processing of LIGO, Virgo, Fermi and radio data, and the design and implementation of improved search methods. The detection of continuous gravitational waves will provide glimpses into the invisible population of neutron stars that inhabits our Galaxy and shed light on their internal structure and evolutionary history. The discovery of new neutron stars in short period binaries and near the Galactic center will improve our understanding of stellar evolution and populations, help study the black hole at the Galactic center, and provide stringent tests of general relativity. Discovery of new millisecond radio pulsars will improve the ability of "pulsar timing arrays" to detect low-frequency gravitational waves.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.