Pulsar astronomy: a powerful tool for fundamental astrophysics

射电脉冲星是中子星，是大质量恒星超新星爆炸后留下的致密天体。这样一颗恒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多次不等。脉冲星在我们看来就像一座灯塔，它产生的无线电波束在扫过地球上的射电望远镜时形成“脉冲”。这项研究计划的主要目标之一是用阿雷西博和格林班克（GBT）望远镜跟踪几颗旋转最快的脉冲星，以寻找或限制可能在天空中彼此靠近的脉冲星共同出现的微小时间不规则性，表明以年振荡频率通过的引力波。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。

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.