Herschel/SPIRE observations of Uranus are used to search for stratospheric hydrogen chloride (HCl) emission at 41.74 cm −1 . HCl was not detected and instead 3 σ upper limits were determined; <6.2 ppb (<2.0 × 10 14 molecules cm −2 ) for a 0.1 mbar step profile and <0.40 ppb (<1.2 × 10 14 molecules cm −2 ) for a 1 mbar step profile. HCl is expected to have an external source and these upper limits are consistent with abundances of other external species (CO, H 2 O, CO 2 ) and a solar composition source.

中文翻译：

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来自Herschel / SPIRE的天王星平流层HCl上限

天王星的Herschel / SPIRE观测用于寻找41.74 cm -1处的平流层氯化氢（HCl）排放。未检测到HCl，而是确定了3σ上限。对于0.1 mbar的阶跃曲线，<6.2 ppb（<2.0×10 14分子cm -2），对于1 mbar的阶跃曲线<0.40 ppb（<1.2×10 14分子cm -2）。预计HCl具有外部来源，并且这些上限与其他外部物质（CO，H 2 O，CO 2）和太阳能组合物来源的含量一致。