Plasma Flow Measurement using Mach Probe and Laser-Induced Fluorescence in Weakly Magnetized Plasmas

A Mach probe (MP) is generally used for the measurement of plasma flow velocity in the edge of magnetic fusion devices, space propulsion systems, processing plasmas, sheath and pre- sheath regions. Although several un-magnetized MP theories are available, their validity has not been fully confirmed, and should be checked by comparative (or simultaneous) measurement with another diagnostic tool such as laser-induced fluorescence (LIF). The plasma flow velocity was measured via an MP and LIF method in Ar plasma generated by LaB$_6$ cathode of Diversified Plasma Simulator - Modification (DiPS-M). The MP and LIF measurements are performed in the ranges of magnetic field intensities, $100 < B < 1000$ (Gauss) and the various neutral pressures, $1