Comparative study of measurement methods of atomic oxygen flux in ground-based simulation facility

Atomic oxygen is the predominant component and one of the most severe environment factors. In low earth orbit (LEO), it may cause severe erosion of spacecraft materials. The measurement of atomic oxygen flux is the foundation in the study of atomic oxygen effects, an important parameter for quantifying the exposure level of atomic oxygen and evaluating the atomic oxygen-duration lifetime of spacecraft components and materials in LEO. The principles and working processes of the commonly used measurement methods in ground-based simulation facilities were introduced, including Kapton-mass loss method, NO₂ titration method, Ag surface catalysis method, emission spectrum method, Ag-resistance method and the semiconductor sensor method. The characteristics and utilities of the methods were summarized. In addition, the atomic oxygen flux of a ground-based simulation facility was measured using Kapton-mass loss method, Ag surface catalysis method and emission spectrum method. Based on the comparison of the measurement results, the accuracy of each method was analyzed.