High‐resolution, VUV (147–201 nm) photoabsorption cross sections for C2H2 at 195 and 295 K
High‐resolution, VUV (147–201 nm) photoabsorption cross sections for C2H2 at 195 and 295 K
复制标题
195 和 295 K 下 C2H2 的高分辨率 VUV (147–201 nm) 光吸收截面
DOI：
10.1029/91je01739
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发表时间：
1991
影响因子：
--
通讯作者：
G. Stark
中科院分区：
文献类型：
--
作者：
Peter L. Smith;K. Yoshino;W. Parkinson;K. Ito;G. Stark
乙炔，C2H2，在巨行星大气的光化学中起着重要的作用，部分原因是它在145-200 nm区域有很强的吸收特性，那里有显著的太阳通量。在行星大气温度下需要精确的光吸收截面数据来解释观测结果和建立可靠的光化学模型。我们测量了在195和295 K下，在147-201 nm波长范围内的乙炔的光吸收截面。（295 K测量扩展到137 nm。）所使用的高分辨率光谱仪的仪器带宽比以前测量中使用的仪器带宽小，因此产生的横截面受仪器效应的影响较小。结果表明，热带对C2H2的室温吸收光谱的贡献虽小，但意义重大。行星大气的光化学模型应该采用在这些大气温度下测量的横截面。
Acetylene, C2H2, plays an important role in the photochemistry of the atmospheres of the giant planets, in part because of its strong absorption features in the 145–200 nm region where there is significant solar flux. Accurate photoabsorption cross section data at the temperatures of planetary atmospheres are required for interpretation of observations and for reliable photochemical models. We have measured the photoabsorption cross sections of acetylene at 195 and 295 K in the wavelength range 147–201 nm. (The 295 K measurements extend to 137 nm.) The high-resolution spectrometers employed had instrumental bandwidths smaller than those used in previous measurements and therefore produced cross sections that are less influenced by instrumental effects. Our results indicate that hot bands make small but significant contributions to the room temperature absorption spectrum of C2H2. Photochemical models of planetary atmospheres should employ cross sections measured at the temperatures of these atmospheres.