Portable Multi-Channel Intensity Interferometer

在不断努力获得更好的宇宙物体图像的过程中，重点通常集中在轨道天文台或更大的具有激光修正大气湍流的地面设施上。两者都是有身体限制的昂贵的努力。另一种完全不同的方法，强度干涉测量，在射电天文学中有着重要的历史，但上一次认真地用于光学系统是在20世纪70年代的S，当时使用的是简单的探测器。南康涅狄格州立大学(SCSU)的E.Horch博士已经认识到，今天非常灵敏、极快的固态探测器促使人们重新检查这项技术，因为它将提供利用一小批廉价、中等尺寸的望远镜和商业仪器获得轨道双星的分离、恒星直径，甚至完整的恒星图像的可能性。事实上，南加州州立大学的项目正在被推广为一项非常适合学生参与的活动。天文学的强度干涉测量利用玻色子(因此也包括光子)的玻色-爱因斯坦关联来提供辐射源的角大小的信息。霍奇博士预测，对于分布在南加州大学校园内的口径略小于1米的望远镜，角分辨率可以达到0.1毫角秒，而目视星等可以达到~3.5级，从而可以对大约200颗恒星进行详细检查。作为比较，太阳移动到这样一个距离，产生这样的表观震级，其角直径应该是2毫角秒。此外，通过使用量子效率接近0.5、时间响应约为0.1纳秒的单光子雪崩二极管(SPAD)阵列，以及使用GPS技术记录的数据，可以在多个波段同时监测这一效应。NSF天文科学部通过参与重大研究仪器计划，为开发现代双筒光学干涉仪阵列提供资金。

In the continual effort to obtain better images of objects in the universe, the emphasis has generally been centered on orbiting observatories or ever-larger ground-based facilities with laser correction of atmospheric turbulence. Both are expensive endeavors with physical limitations. A quite different approach, intensity interferometry, has a significant history in radio astronomy, but was last seriously used for the optical regime in the 1970's using the simple detectors available at the time. Dr. E. Horch of Southern Connecticut State University (SCSU) has recognized that today's very sensitive, extremely fast solid-state detectors motivates that the technique be re-examined, as it would offer the possibility of obtaining separations of orbiting binary stars, stellar diameters, and even complete stellar images using a small array of inexpensive, modest-sized telescopes and commercially available instrumentation. Indeed, the SCSU project is being promoted as an activity well-suited to student involvement at a small undergraduate university.Intensity interferometry for astronomy utilizes the Bose-Einstein correlation of bosons (and therefore photons) to provide information on the angular size of the radiating source. For telescopes with somewhat less than 1-m aperture distributed over the SCSU campus, Dr. Horch predicts that an angular resolution of 0.1 milliarcseconds can be achieved down to a visual magnitude of ~3.5, allowing detailed inspection of about 200 stars. For comparison, the Sun moved to a distance that yields this apparent magnitude would have an angular diameter of 2 milliarcseconds. Moreover, the effect can be monitored in several wavebands simultaneously through the use of Single Photon Avalanche Diode (SPAD) arrays that have quantum efficiencies near 0.5 and time response of ~0.1 nanoseconds, and the data recorded using GPS technology.Funding for the development of a modern two-telescope prototype of an intensity interferometer array for the optical is being provided by NSF's Division of Astronomical Sciences through its participation in the Major Research Instrumentation program.