标题： 漫反射辐射传输模型在Sombrero星系的恒星和尘埃中的应用 显示英文标题

标题： Panchromatic radiative transfer modeling of stars and dust in the Sombrero galaxy

摘要： 我们对Sombrero星系M104的尘埃能量平衡进行了详细研究。通过完整的辐射转移分析，包括散射、吸收和热再辐射，我们构建了能够再现光学/近红外波长图像、观测到的恒星SED以及V和R_C波段次要轴消光曲线的模型。一个仅包含老年恒星种群来加热尘埃的标准模型，在红外波长处的尘埃发射观测值被低估了约3倍。在基本模型中补充内盘（SFR ~ 0.21 Msun/yr）和尘埃环（SFR ~ 0.05 Msun/yr）中低恒星形成活动的年轻恒星成分后，我们能够解决Sombrero星系在100\mum 波长以下的尘埃能量预算差异。为了说明超过100\mum 的远红外/亚毫米发射增加，我们提出一个分布在静止云块中的额外尘埃成分。这种具有团块状尘埃结构的模型预测三分之二的总尘埃含量（~ 2.8 x 10^7 Msun）存在于没有相关嵌入源的致密尘埃云中。尽管Sombrero星系中团块状尘埃结构的假设得到了高分辨率光学数据的支持，但我们不能排除在亚毫米波长处，具有更高尘埃发射率的尘埃颗粒可能部分解释了能量预算的差异。 显示英文摘要

摘要： We present a detailed study of the dust energy balance in the Sombrero galaxy M104. From a full radiative transfer analysis, including scattering, absorption and thermal re-emission, we construct models that can reproduce images at optical/near-infrared wavelengths, the observed stellar SED and the minor axis extinction profiles in the V and R_C band. A standard model, that contains only an old stellar population to heat the dust, underestimates the observations of dust emission at infrared wavelengths by a factor of ~ 3. Supplementing this basic model with a young stellar component of low star formation activity in both the inner disk (SFR ~ 0.21 Msun/yr) and dust ring (SFR ~ 0.05 Msun/yr), we are capable of solving the discrepancy in the dust energy budget of the Sombrero galaxy at wavelengths shortwards of 100 \mum. To account for the increased FIR/submm emission beyond 100 \mum, we propose a additional dust component distributed in quiescent clumps. This model with a clumpy dust structure predicts three-quarters of the total dust content (~ 2.8 x 10^7 Msun) to reside in compact dust clouds with no associated embedded sources. Although the assumption of a clumpy dust structure in the Sombrero galaxy is supported by high-resolution optical data, we cannot rule out the possibility that dust grains with a higher dust emissivity account for part of the discrepancy in the energy budget at submm wavelengths.