Fig. 1.

The normalized potential profiles of the dust-plasma cloud (eφ _c /kT _e , dot-dash line), the embedded dust (eΦ _d /kT _e , dotted line), and the spacecraft as functions of P. Two spacecraft potential profiles represent cases with different speeds: 8kms-1 (eΦ _sc1 kT _e , solid line) and 16kms⁻¹ (eΦ _sc2 /kT _e , dash line). With increasing P the SC potential becomes less negative because of the reduction of free electron density as well as the ion collection from the impact-generated plasma.