Cash W, Shipley A, Osterman S, Joy M
University of Colorado, Boulder 80309-0389, USA.
Nature. 2000 Sep 14;407(6801):160-2. doi: 10.1038/35025009.
Starting with Galileo's observations of the Solar System, improvements of an order of magnitude in either the sensitivity or resolution of astronomical instruments have always brought revolutionary discoveries. The X-ray band of the spectrum, where exotic objects can have extremely high surface brightness, is ideally suited for significant improvements in imaging, but progress has been impeded by a lack of optics of sufficiently high sensitivity and quality. Here we present an X-ray interferometer design that is practical for adaptation to astronomical observatories. Our prototype interferometer, having just under one millimetre of baseline, creates fringes at 1.25 keV with an angular resolution of 100 milliarcseconds. With a larger version in orbit it will be possible to resolve X-ray sources at 10(-7) arcseconds, three orders of magnitude better than the finest-resolution images ever achieved on the sky (in the radio part of the spectrum) and over one million times better than the current best X-ray images. With such resolutions, we can study the environments of pulsars, resolve and then model relativistic blast waves, image material falling into a black hole, watch the physical formation of astrophysical jets, and study the dynamos of stellar coronae.
从伽利略对太阳系的观测开始，天文仪器在灵敏度或分辨率方面每提高一个数量级，总会带来革命性的发现。光谱的X射线波段，奇异天体在该波段可具有极高的表面亮度，非常适合大幅提升成像效果，但由于缺乏灵敏度和质量足够高的光学器件，进展受到了阻碍。在此，我们展示一种适用于天文观测台的实用X射线干涉仪设计。我们的原型干涉仪基线略小于1毫米，在1.25千电子伏特下产生条纹，角分辨率为100毫角秒。若在轨道上使用更大版本，将有可能分辨出角秒级为10(-7)的X射线源，比天空中（在光谱的射电部分）迄今获得的最高分辨率图像要好三个数量级，比当前最佳X射线图像要好一百多万倍。有了这样的分辨率，我们就能研究脉冲星的环境、分辨并模拟相对论性激波、对落入黑洞的物质成像、观测天体物理喷流的物理形成过程，以及研究恒星日冕的发电机效应。
