Discharge parameters of PlasmaKristall-4BU: A modifiable dusty plasma experiment

The Plasmakristall-4 (PK-4) experiment is used for experiments under microgravity conditions with dusty plasmas on the International Space Station. The experiment PK-4BU is based on a similar experimental concept but offers the possibility of modifications to the device to gain crucial information on the influence of several parameters on the experiment. Within this work, electrostatic probe and spectroscopy measurements have been taken within the PK-4BU experiment to determine electron temperature T_e, electron density n_e, and plasma potential φ as well as to gain information about the composition of the background gas. It has been found that the discharge parameters are similar to results from comparable devices, while a small influence of impurities within the working gas cannot be neglected.