タイトル | The unusual dust-scattering properties in the reflection nebula CED 201 |
著者(英) | Bohlin, R. C.; Witt, A. N.; Graff, S. M.; Stecher, T. P. |
著者所属(英) | Toledo Univ.|Space Telescope Science Inst.|NASA Goddard Space Flight Center |
発行日 | 1987-10-15 |
言語 | eng |
内容記述 | Spectrophotometric data available from ground-based and IUE observations of the reflection nebula CED 201 and its illuminating star BD + 69.1231 deg are analyzed to deduce the most likely star-nebula geometry and the wavelength dependence of the scattering characteristics of the nebular grains. The dust albedo is found to decline from 0.72 at V to probably less than 0.2 at lambda less than 2000 A, explaining the unusual red color of this reflection nebula. The wavelength dependence of the optical depth and of the phase function asymmetry in the visible suggests the existence of a narrow size distribution of grains, skewed toward larger than normal particle sizes. CED 201 is one of two reflection nebulae with positive evidence for enhanced scattering in the long-wavelength wing of the 2175 A dust extinction feature, also pointing toward larger than average grains. |
NASA分類 | ASTROPHYSICS |
レポートNO | 88A13852 |
権利 | Copyright |
URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/374296 |
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