Constraints on the density and distance of the outflow. Top: schematic illustrating a simple scenario: a clumpy outflow stream moving vertically from near the accretion disk, with the clump represented by the circle. Bottom: Density (left) and distance (right) constraints derived from the geometrical limits (n_low and R_upp) and escape velocity (n_esc and R_esc). Stars mark the density and distance values assuming that a clumpy component, observed during the decay phase, was launched at the pre-flare onset. The dashed line shows the density and distance limits estimated from the duration of the 8.4 keV dip during the decay phase.