Dust Properties in the Far-ultraviolet in Ophiuchus
نویسندگان
چکیده
We have derived the albedo (a) and phase function asymmetry factor (g) of interstellar dust grains at 11008 using archival Voyager observations of diffuse radiation in Ophiuchus. We have found that the grains are highly forwardscattering, with g 1⁄4 0:55 0:25 and a 1⁄4 0:40 0:10. Even though most of the gas in this direction is in the Ophiuchus molecular cloud, the diffuse FUV radiation is almost entirely due to scattering in a relatively thin foreground cloud. This suggests that one cannot assume that the UV background is directly correlated with the total amount of gas in any direction. Subject headinggs: dust, extinction — infrared: ISM — ultraviolet: ISM
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