标题： 10.7 GHz处宇宙微波背景辐射温度的绝对测量 显示英文标题

标题： An Absolute Measurement of the Cosmic Microwave Background Radiation Temperature at 10.7 GHz

摘要： 一个球载实验测量了宇宙微波背景辐射（CMBR）在10.7 GHz处的绝对温度为Tcmbr = 2.730 ± .014 K。该误差是多个系统误差的平方和，统计误差小于0.1 mK。 该仪器由一个冷却的波纹喇叭天线耦合到一个全功率辐射计组成。 一个低温机械波导开关交替将辐射计连接到喇叭和内部参考负载上。 天空信号与参考负载之间的小测得温差（≤ 20 mK）以及前端低温的应用使系统性仪器校正保持较小。 通过在24公里高度飞行仪器来最小化大气和窗口发射。 一个大的外部接地屏和一个小的内部接地屏保护仪器免受来自地面和气球的杂散辐射影响。 飞行中的测试限制了地面辐射污染的程度，低水平干扰通过在几个窄频带内的观测进行监测。 显示英文摘要

摘要： A balloon-borne experiment has measured the absolute temperature of the cosmic microwave background radiation (CMBR) at 10.7 GHz to be Tcmbr = 2.730 +- .014 K. The error is the quadratic sum of several systematic errors, with statistical error of less than 0.1 mK. The instrument comprises a cooled corrugated horn antenna coupled to a total-power radiometer. A cryogenic mechanical waveguide switch alternately connects the radiometer to the horn and to an internal reference load. The small measured temperature difference (<= 20 mK) between the sky signal and the reference load in conjunction with the use of a cold front end keeps systematic instrumental corrections small. Atmospheric and window emission are minimized by flying the instrument at 24 km altitude. A large outer ground screen and smaller inner screen shield the instrument from stray radiation from the ground and the balloon. In-flight tests constrain the magnitude of ground radiation contamination, and low level interference is monitored through observations in several narrow frequency bands.