Abstract. Sulfur dioxide (SO₂) is an important precursor for formation of atmospheric sulfate aerosol and acid rain. We present an instrument using Broad Band Cavity Enhanced Absorption Spectroscopy (BBCEAS) for the measurement of SO₂ with a minimum limit of detection of 0.6 ppbv using the spectral range 305.5–312 nm and an averaging time of 60 seconds. The instrument consists of high reflectivity mirrors (0.9984 at 310 nm) and a deep UV light source. The effective absorption path length of the instrument is 610 m in a 0.957 m base length. Published reference absorption cross-sections were used to fit and retrieve the SO₂ concentrations and were compared to a diluted standard for SO₂. The comparison was well correlated, R² = 0.9985 with a correlation slope of 1.01.

中文翻译：

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通过宽带腔增强吸收光谱 (BBCEAS) 检测二氧化硫

摘要。二氧化硫 (SO ₂ ) 是形成大气硫酸盐气溶胶和酸雨的重要前体。我们展示了一种使用宽带腔增强吸收光谱 (BBCEAS) 测量 SO ₂的仪器，使用 305.5-312 nm 的光谱范围和 60 秒的平均时间，最低检测限为 0.6 ppbv。该仪器由高反射率反射镜（310 nm 处为 0.9984）和深紫外光源组成。仪器的有效吸收路径长度为 610 m，基长为 0.957 m。已发布的参考吸收截面用于拟合和检索 SO ₂浓度，并与 SO ₂的稀释标准进行比较. 该比较具有良好的相关性，R ²  = 0.9985，相关斜率为 1.01。