Electron density and plasma dynamics of a colliding plasma experiment

• Published in: AIP advances 2016-07, Vol.6 (7)
• Main Authors: Wiechula, J., Schönlein, A., Iberler, M., Hock, C., Manegold, T., Bohlender, B., Jacoby, J.
• Format: Article
• Language: English
• Subjects: CAMERAS; Coaxial plasma accelerators; Collision dynamics; COLLISIONS; COMPARATIVE EVALUATIONS; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ELECTRON DENSITY; Framing cameras; Plasma; Plasma accelerators; PLASMA DENSITY; Plasma dynamics; PLASMA GUNS; PLASMA SHEATH; Plasma sheaths; PULSES; Vacuum chambers; VELOCITY
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.4959590

We present experimental results of two head-on colliding plasma sheaths accelerated by pulsed-power-driven coaxial plasma accelerators. The measurements have been performed in a small vacuum chamber with a neutral-gas prefill of ArH2 at gas pressures between 17 Pa and 400 Pa and load voltages between 4 kV and 9 kV. As the plasma sheaths collide, the electron density is significantly increased. The electron density reaches maximum values of ≈8 ⋅ 1015 cm−3 for a single accelerated plasma and a maximum value of ≈2.6 ⋅ 1016 cm−3 for the plasma collision. Overall a raise of the plasma density by a factor of 1.3 to 3.8 has been achieved. A scaling behavior has been derived from the values of the electron density which shows a disproportionately high increase of the electron density of the collisional case for higher applied voltages in comparison to a single accelerated plasma. Sequences of the plasma collision have been taken, using a fast framing camera to study the plasma dynamics. These sequences indicate a maximum collision velocity of 34 km/s.