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 ± 1.5) · 10⁹ kg during the 2015 apparition. Further, we found that power-laws with q=3.7-0.078+0.57 are consistent with the data. This results in a total of 5.1-4.9+6.0·109 kg of dust being ejected from the nucleus surface, of which 4.4-4.2+4.9·109 kg escape to space and 6.8-6.8+11·108 kg (or an equivalent of 14-14+22 cm over the smooth regions) is re-deposited on the surface. This leads to a dust-to-gas ratio of 0.73-0.70+1.3 for the escaping material and 0.84-0.81+1.6 for the ejected material. We have further found that the smallest dust size must be strictly smaller than ~30μm and nominally even smaller than ~12μm.

在这项工作中，我们提出的结果同时限制了67P / Churyumov-Gerasimenko彗星的粉尘尺寸分布，粉尘气体比，粉尘再沉积的比例以及总的总生产率。我们使用3D直接模拟蒙特卡洛（DSMC）气体动力学代码来模拟在Rosetta任务期间彗星的内部气体昏迷。气体模型受ROSINA / COPS数据约束。此外，我们使用3D尘埃动力学代码（包括气体阻力和核的重力）针对不同时期模拟内部尘埃昏迷。利用先进的尘埃散射特性，这些结果可用于生成可与OSIRIS数据集进行比较的合成图像。这些模拟使我们能够限制粉尘昏迷的性质以及总的气体和粉尘产生率。我们确定总挥发物质量损失为（6。2015年幻影术中为⁹公斤。此外，我们发现q=3。7--0。078+0。57与数据一致。这导致总共5。1个--4。9+6。0·1个09 从核表面喷出的千克灰尘，其中 4。4--4。2+4。9·1个09 公斤逃到太空 6。8--6。8+11·1个08 公斤（或等值的 1个4--14+22在光滑区域上的约5厘米处）重新沉积在表面上。这导致粉尘/气体比为0。73--0。70+1个。3 用于逃生的材料和 0。84--0。81+1个。6用于弹出的材料。我们进一步发现，最小的粉尘尺寸必须严格小于〜30μm，名义上甚至小于〜12μm。