Dependence of the direct drag force and Coulomb drag force on drift velocity and the structure of the photo-evaporation flow with the inclusion of Coulomb drag. Left: direct drag (solid line) and the Coulomb drag on a 300 Å dust grain with charge Zd = 195 (upper dashed line) and a 3000 Å dust grain with charge Zd = 1809 (lower dashed line). Plotted is the dependence of the drag forces on the relative velocity between the gas and the dust, expressed in the Mach number ℳ = vdrift/cs. The dotted horizontal line represents the radiation pressure force at r = 0.1 pc. Right: calculated trajectories of a dust grain with κrp = 6.7 × 103 including the Coulomb drag force. The grains only decouple from the gas very close to the star (i.e., d < 0.025 pc).
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.