Calibration method and uncertainty analysis of fixed angle mirror

A Dante spectrometer mirror calibration method is developed by recovery of X-ray benchmarks without installing reflectivity meter chamber and limit space in 4B7B beamline of BSRF. X-ray benchmark line is achieved by three beamlines aiming. High angle precision is realized by collimation, and chamber state surveillant system was adopted. Mirror calibration uncertainty of angle is 1.0 mrad for the experiment. High precise reflectivity curves have been acquired by repeat installation and in four directions of fixed angle mirror.