论文标题
3.4 $ $ m和10 $μ$ m的功能“ ratodust”的介电函数和对极化的预测
The Dielectric Function of "Astrodust" and Predictions for Polarization in the 3.4$μ$m and 10$μ$m Features
论文作者
论文摘要
星际灰尘材料的介电功能是使用红外灭绝和极化的观测值建模的，以及估计星际灰尘的质量。假定“天体”材料是无定形硅酸盐和其他材料的混合物，包括在3.4 $ $ $ m处产生吸收特征的碳氢化合物。 10 $ $ m m的极化曲线的详细形状取决于假定的孔隙率和晶粒的形状，但是10 $ $ $ m specyropolarigetric的数据还不够好，无法清楚地偏爱一种形状，而不是限制孔隙率。预期的3.4 $ $ m特征极化与现有上限一致，前提是3.4 $ $ m $ m的吸收优先位于晶粒表面层中；不需要单独的非对准碳粒晶粒。我们预测3.4 $ $ m的极化功能为$（ΔP）_ {3.4μ{\ rm m}}}}/p（10μ{\ rm m}）\大约0.016 $，略低于当前上限。还计算了在sumbm波长处通过相同晶粒的极化。
The dielectric function of interstellar dust material is modeled using observations of extinction and polarization in the infrared, together with estimates for the mass of interstellar dust. The "astrodust" material is assumed to be a mix of amorphous silicates and other materials, including hydrocarbons producing an absorption feature at 3.4$μ$m. The detailed shape of the 10$μ$m polarization profile depends on the assumed porosity and grain shape, but the 10$μ$m spectropolarimetric data are not yet good enough to clearly favor one shape over another, nor to constrain the porosity. The expected 3.4$μ$m feature polarization is consistent with existing upper limits, provided the 3.4$μ$m absorption is preferentially located in grain surface layers; a separate population of non-aligned carbonaceous grains is not required. We predict the 3.4$μ$m polarization feature to be $(Δp)_{3.4μ{\rm m}}/p(10μ{\rm m})\approx 0.016$, just below current upper limits. Polarization by the same grains at submm wavelengths is also calculated.
