同步辐射光束线上存在的碳污染是影响光束线特别是软X光束线传输效率的重要原因,污染的生成与镜箱腔壁上存在有少量的油有关。为了获得更加洁净的真空室，通过辉光放电对镜箱真空室壁进行清洗，力争从源头上减少光学元件碳污染的产生。设计并搭建了一套应用在同步辐射光束线镜箱上的辉光放电清洗系统，并研究了装置在不同真空度下辉光的伏安特性。利用四极质谱对辉光放电前后及过程中镜箱内的残气进行分析。研究得出，真空室表面残留油分子的初步裂解产物主要是分子量为69的粒子。通过辉光放电清洗，真空室内残存的微量油大分子的（分子量为39,41,43,55,57,69,71）减少幅度达到50%。辉光放电清洗对真空腔体内表面油分子有明显的去除效果。本文研究的内容对于减少光束线站特别是软X射线光束线上碳污染具有重要意义。

Carbon contamination in a synchrotron radiation (SR) beamline is a significant factor affecting the transmission efficiency in the beamline, particularly in a soft X-ray beamline. Currently, the main solution to carbon contamination is to clean or replace the contaminated optical components. A large number of experimental studies have shown that the formation of carbon contamination is related to the presence of a small amount of oil on the chamber wall. Therefore, the purpose of this study was to clean the vacuum chamber wall of the mirror box and obtain a cleaner vacuum chamber by glow discharge, striving to fundamentally prevent the formation of carbon contamination. This paper applied the Glow Discharge Cleaning (GDC) system to the Shanghai Synchrotron Radiation Facility (SSRF) beamline mirror chamber. The volt-ampere characteristics of the device under different vacuum pressures were studied. Mass spectrometry was then performed to analyze the residual gas in the mirror chamber before and after the glow discharge as well as the GDC process. The result shows that the primary cracking products of residual oil molecules in the vacuum chamber were mainly particles with molecular weight of 69. After being cleaned by glow discharge, the quantity of oil molecules (molecular weight 39, 41, 43, 55, 57, 69, 71) can be reduced by 50%, proving that glow discharge has a remarkable effect on removing oil molecules from the surface of the mirror chamber in the beamline. The GDC system is of great significance to reduce carbon contamination, especially in soft X-ray beamlines.