We present initial results from the first optical spectroscopic survey of high latitude Galactic cirrus clouds. The observed shape of the cirrus spectrum does not agree with that of scattered ambient Galactic starlight. This mismatch can be explained by the presence of Extended Red Emission (ERE) in the diffuse interstellar medium, as found in many other astronomical objects, probably caused by photoluminescence of hydrocarbons. The integrated ERE intensity, I_ERE \approx 1.2 x 10^{-5} erg s^{-1} cm^{-2} sr^{-1}, is roughly a third of the scattered light intensity, consistent with recent color measurements of diffuse Galactic light. The peak of the cirrus ERE (lambda_{0} \sim 6000 AA) is shifted towards short (bluer) wavelengths compared to the ERE in sources excited by intense ultraviolet radiation, such as HII regions (lambda_{0} sim 8000 AA); such a trend is seen in laboratory experiments on hydrogenated amorphous carbon films.
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机译：我们展示了来自高纬度银河卷云的第一次光谱调查的初步结果。卷云光谱的观测形状与周围环境银河星光的散射形状不一致。这种不匹配现象可以通过星际弥漫性介质中存在扩展的红色发射（ERE）来解释，正如在许多其他天文物体中发现的那样，很可能是碳氢化合物的光致发光引起的。集成的ERE强度I_ERE \大约1.2 x 10 ^ {-5} erg s ^ {-1} cm ^ {-2} sr ^ {-1}，大约是散射光强度的三分之一，与最近的颜色一致银河漫射光的测量。与强紫外线辐射激发的光源（如HII区）中的ERE相比，卷云ERE（lambda_ {0} \ sim 6000 AA）的峰向短（蓝色）波长移动；这种趋势在氢化非晶碳膜的实验室实验中可见。
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