论文标题
粉尘与气体比，尺寸分布和灰尘倒下的比例67p/churyumov-gerasimenko：通过链接内部comae的光学和动力学特性的推论
The dust-to-gas ratio, size distribution, and dust fall-back fraction of comet 67P/Churyumov-Gerasimenko: Inferences from linking the optical and dynamical properties of the inner comae
论文作者
论文摘要
在这项工作中，我们提出的结果同时限制了67p/churyumov-Gerasimenko彗星的灰尘尺寸分布，灰尘 - 气体比例，灰尘重置的比例和总质量产量。我们使用3D直接模拟蒙特卡洛（DSMC）气体动力学代码在Rosetta任务期间模拟彗星的内部气体昏迷。气体模型受到Rosina/COPS数据的约束。此外，我们使用3D尘埃动力学代码（包括气阻力和细胞核的重力）模拟了内部尘埃昏迷。使用先进的灰尘散射属性，这些结果用于产生可以将其与Osiris数据集进行比较的合成图像。这些模拟使我们能够限制灰尘昏迷的特性以及总的气体和灰尘生产率。 我们确定了2015年幻想期间的$（6.1 \ pm 1.5）\ CDOT 10^9 $ 〜kg的总挥发性质量损失。此外，我们发现具有$ q = 3.7^{+0.57} _ { - 0.078} $的幂律与数据一致。这将导致总共$ 5.1^{+6.0} _ { - 4.9} \ cdot10^9 $〜kg的灰尘从核表面弹出，其中$ 4.4^{+4.9} _ { - 4.2} \ cdot10^cdot10^9 $ 〜kg 9 $ 〜kg space and $ 6.8^$ 6.8^{+11}} _ 6.+cd 6.8.kot} （或相当于$ 14^{+22} _ { - 14} $ 〜cm在平滑区域上）的（在表面上重新沉积）。这导致逃逸材料的灰尘与气体比为$ 0.73^{+1.3} _ { - 0.70} $，$ 0.84^{+1.6} _ { - 0.81} $用于弹射材料。我们进一步发现，最小的灰尘尺寸必须严格小于$ \sim30μ$ m，名义上甚至小于$ \sim12μ$ m。
In this work, we present results that simultaneously constrain the dust size distribution, dust-to-gas ratio, fraction of dust re-deposition, and total mass production rates for comet 67P/Churyumov-Gerasimenko. We use a 3D Direct Simulation Monte Carlo (DSMC) gas dynamics code to simulate the inner gas coma of the comet for the duration of the Rosetta mission. The gas model is constrained by ROSINA/COPS data. Further, we simulate for different epochs the inner dust coma using a 3D dust dynamics code including gas drag and the nucleus' gravity. Using advanced dust scattering properties these results are used to produce synthetic images that can be compared to the OSIRIS data set. These simulations allow us to constrain the properties of the dust coma and the total gas and dust production rates. We determined a total volatile mass loss of $(6.1 \pm 1.5) \cdot 10^9$~kg during the 2015 apparition. Further, we found that power-laws with $q=3.7^{+0.57}_{-0.078}$ are consistent with the data. This results in a total of $5.1^{+6.0}_{-4.9}\cdot10^9$~kg of dust being ejected from the nucleus surface, of which $4.4^{+4.9}_{-4.2}\cdot10^9$~kg escape to space and $6.8^{+11}_{-6.8}\cdot10^8$~kg (or an equivalent of $14^{+22}_{-14}$~cm over the smooth regions) is re-deposited on the surface. This leads to a dust-to-gas ratio of $0.73^{+1.3}_{-0.70}$ for the escaping material and $0.84^{+1.6}_{-0.81}$ for the ejected material. We have further found that the smallest dust size must be strictly smaller than $\sim30μ$m and nominally even smaller than $\sim12μ$m.
