AI 中文总结
研究人员构建了分辨率达1秒差距、距太阳1.25千秒差距的本地远紫外星际辐射场三维模型LightCube，发现其在不同区域变化显著，且低紫外辐射区紫外流量与总选择消光比R_V呈正相关。
AI 中文摘要
我们提出了本地星际辐射场（ISRF）的紫外（UV）三维模型。利用TD1星表的紫外流量测量数据以及盖亚（Gaia）和依巴谷（Hipparcos）的恒星距离数据，我们构建了一个恒星表，这些恒星预计会主导近邻星系的紫外流量。我们使用辐射传输代码DIRTY来模拟这些恒星发出的光子穿过三维尘埃图的传播过程，其中包含散射和吸收效应。最终得到的是LightCube，这是一个距离太阳达1.25千秒差距（kpc）的紫外ISRF模型，最大线性分辨率为1秒差距（pc）。我们在TD1的四个波段（1565埃、1965埃、2365埃和2740埃）中模拟了ISRF，还计算了整个远紫外（FUV）范围的单一值，并得出太阳处的ISRF在912埃至2000埃范围内为5.65×10⁻¹⁴ erg cm⁻³。模拟的ISRF变化显著，在致密区域观测到超过一个数量级的变化，在低密度区域的变化约为其一半。通过将LightCube与总选择消光比R_V的三维分布估计值进行比较，我们发现低紫外辐射区域的紫外流量与R_V之间存在正相关关系。
英文摘要
We present a three-dimensional model of the local interstellar radiation field (ISRF) in the ultraviolet (UV). Using UV flux measurements from the TD1 catalog and stellar distances from Gaia and Hipparcos, we construct a catalog of stars that we expect to dominate the UV flux in the nearby Galaxy. We use the radiative transfer code DIRTY to model the propagation of photons from these stars through a 3D dust map, including the effects of scattering and absorption. The result is LightCube, a model of the ultraviolet ISRF out to 1.25 kpc from the Sun, with a maximum linear resolution of 1 pc. We model the ISRF in the four TD1 bands (1565 A, 1965 A, 2365 A, and 2740 A), as well as a single value for the full FUV range, and calculate the ISRF at the Sun to be 5.65$\times$10$^{-14}$ erg cm$^{-3}$ from 912 A to 2000 A. The modeled ISRF is quite variable, with more than an order of magnitude variation seen in dense regions, and about half that in lower density regions. By comparing LightCube to an estimate of the 3D distribution of total-to-selective extinction ratio, $R_V$, we find a positive correlation between UV flux and $R_V$ in regions of low UV radiation.
Comments18 pages, 11 figures. Submitted to ApJ
