Precision Mapping of the Cosmic Microwave Background Radiation

摘要9619374 Meyer是为测量宇宙微波背景辐射的空间变化而设计的TOPHAT长时间气球实验。它利用了气球有效载荷的一种新颖结构，将望远镜本身安装在气球的顶部，以消除由于气球的结构和地球位于望远镜天线的旁瓣而造成的许多系统误差来源，同时电子和控制设备将以通常的方式悬挂在气球下方。由此得到的宇宙图有五个光谱波段，波长在0.45到2.3毫米之间，将提供大片天空(1800平方度)上CMBR各向异性的前所未有的细节。CMBR的变化带有早期宇宙中物质分布的印记，大约在大爆炸后30万年。各向异性的性质可以用来敏感地测试早期和现在的各种宇宙性质模型；因此，tophat将有助于解决诸如宇宙是开放的还是封闭的，以及宇宙中缺失(暗)质量的性质是什么等问题。这项实验将在南极洲的麦克默多飞行。该项目由丹麦空间研究所、美国宇航局和美国国家科学基金会联合发起。***

Abstract 9619374 Meyer The TopHat long-duration balloon experiment is designed to measure the spatial variations in the cosmic microwave background radiation (CMBR). It utilizes a novel configuration of the balloon payload, with the telescope itself being mounted on the top of the balloon in order to eliminate many of the sources of systematic errors caused by the balloon's structures and the Earth being in the sidelobes of the telescope antenna, while the electronics and control equipment will be suspended below the balloon in the usual fashion. The resulting map of the cosmos in five spectral bands with wavelengths between 0.45 and 2.3 mm, will provide unprecedented detail in the CMBR anisotropy over a large (1800 square degree) patch of the sky. The variations in the CMBR carry the imprint of the distribution of matter in the early universe, approximately 300,000 years after the big bang. The nature of the anisotropy can be used to sensitively test various models of the nature of the universe, both early-on and now; hence, TopHat will contribute to the resolution of such questions as whether the universe is open or closed and what is the nature of the missing (dark) mass in the universe. This experiment will be flown from McMurdo, Antarctica. The project is jointly sponsored by the Danish Space Research Institute, NASA and NSF. ***