Dust distribution in radiation pressure outflow. Application to the   BD+31d643 disk
  The radial distribution of dust has been calculated in outflows driven by radiation pressure in which the gas drag is taken into account. It is shown that the dust distribution in the newly discovered candidate disk around BD+31d643 can be explained by this simple model, provided that the ambient gas of the surrounding cluster IC 348 has a density $\rho\sim 10^4~$cm$^{-3}$. The dust is probably produced within 2300 AU from the central binary star. 
A. Lecavelier des Etangs, A. Vidal-Madjar, R. Ferlet