Influence of Conical Wire Array Geometry on Flow and Temperature Profiles Measured via Thomson Scattering and Optical Techniques

Conical wire arrays with different opening angles are used as load of a 400kA, 1kA/ns generator. The differences in opening angle allow the study of the influence of the array geometry on the jet properties. The characterization of the jets is performed using a combination of advanced diagnostic techniques, including moiré schlieren deflectometry, visible self-emission spectroscopy, and optical Thomson scattering. The results reveal that, under the experimental conditions, the plasma jets exhibit electron temperatures ranging from $8$ to $17$ eV, increasing along the axial direction. In contrast, the ion temperature decreases from approximately $35$ eV near the base of the jet to about $20$ eV at higher axial positions. The electron density profile peaks at $\sim 4\times {10}^{18}$ cm${}^{-3}$ in the central lower region of the jet and decreases with height exponentially with a characteristic lenght $L_n=$2.86 mm. This behavior is reproducible and independent of the conical array geometry. However, the cone opening angle significantly affect the jet propagation velocity, with larger opening angles producing higher axial velocities ($V_{\phi ={40}^{\circ }}\approx 125\pm 3$ km/s, $V_{\phi ={20}^{\circ }}\approx 98\pm 5$ km/s), demonstrating that the cone geometry provides effective control over the jet propagation velocity.