Development of a coaxial tapered electromagnetic shock tube for beam-plasma non-linear interaction experiments

A coaxial electromagnetic shock tube was developed to produce a non-ideal plasma target with Γ ∼ 0.1 (Γ: Plasma coupling constant) for non-linear interaction experiments between ion beams and plasmas. To evaluate the shock velocity, we photographed the trajectory of the shock front along the tube by a streak camera. From these measurements, we found that the shock waves are strong enough to produce a non-ideal plasma in the tube. To reduce the plasma thickness for the stopping power measurements, the effective diameter of the tube was reduced by using a tapered section. The effects of the tapered section on the shock velocity and the shape of the shock front were examined. Using a 30 tapered section, the shock velocity was increased up to 54 km/s compared with 47 km/s for a straight tube.