Pulsar astronomy: a powerful tool for fundamental astrophysics

射电巨星是中子星，是大质量恒星超新星爆炸后留下的致密物体。 这样一颗星星的质量大约是太阳的1.5倍，但直径只有20公里左右，它可以在任何地方旋转，从每几秒一次到每秒700多次。 脉冲星在我们看来就像一座灯塔，它产生的无线电波束扫过地球上的射电望远镜时会产生“脉冲”。 这项研究计划的主要目标之一是用阿雷西博和绿色银行（GBT）望远镜跟踪几个旋转最快的恒星，以寻找或限制可能出现在天空中彼此靠近的恒星中的微小时间不规则性，这表明引力波的振荡频率为几年。 这是一个具有挑战性的项目，需要与世界各地的合作者一起完成。 这个重大项目的数据也将用于探索尽可能多的脉冲星双星系统的质量，试图揭示不同类型系统中双星演化特性的差异。 相对论系统，通常有两个中子星在一个接近的轨道，允许严格的测试爱因斯坦的相对论在潜在的特殊制度附近非常紧凑的对象。 这项研究将通过对双脉冲星和其他相对论系统的观测来进行这种测试。 该研究计划还包括在阿雷西博和GBT搜索双星，以识别用于寻找引力波的新双星，建立统计数据以更好地了解年轻和快速旋转双星的种群，并找到全新类型的双星，包括意想不到的双星类型。 最后，该计划将展望未来，在即将到来的澳大利亚平方公里阵列探路者望远镜上开展脉冲星搜索和计时模式的工作，并展望计划中的超灵敏平方公里阵列的脉冲星科学。

Radio pulsars are neutron stars, the compact objects left behind after the supernova explosions of massive stars. Such a star has a mass about one and a half times that of our Sun but a diameter of only about 20 km, and it can spin anywhere from once every few seconds to more than 700 times per second. A pulsar appears to us as a kind of lighthouse, producing beams of radio waves which result in "pulses" as they sweep past our radio telescopes on Earth. One of the main goals of this research program is to track several of the fastest-spinning pulsars with the Arecibo and Green Bank (GBT) telescopes in order to look for or constrain tiny timing irregularities that might appear in common for pulsars close to each other on the sky, indicating the passage of gravitational waves with oscillation frequencies of years. This is a challenging project to be done with collaborators around the world. The data from this major project will also be used to explore the masses in as many pulsar binary systems as possible, trying to shed light on the differences in binary evolution properties in different types of systems. Relativistic systems, typically with two neutron stars in a close orbit, allow stringent tests of Einstein's theory of relativity in the potentially special regime near very compact objects. The research will pursue such tests via observations of the double pulsar and other relativistic systems. The research program also incorporates searches for pulsars at Arecibo and the GBT, to identify new pulsars to use to look for gravitational waves, to build up statistics to better understand the populations of both young and fast-spinning pulsars, and to find entirely new types of pulsars, including unexpected types of binaries. Finally, the program will look to the future, enabling work on pulsar search and timing modes on the upcoming Australian Square Kilometre Array Pathfinder telescope and looking ahead to pulsar science with the planned ultra-sensitive Square Kilometre Array.