A Probe Head for Simultaneous Measurements of Electrostatic and Magnetic Fluctuations in ASDEX Upgrade Edge Plasma

For ASDEX Upgrade (AUG) a new probe head was developed for simultaneous measurements of electric and magnetic fluctuations in the edge plasma region. The probe head consists of a cylindrical graphite case. On the front side six graphite pins are mounted. With this arrangement the poloidal and radial electric field components, the ion saturation current and the current-voltage characteristic can be registered simultaneously. Inside the graphite case a magnetic sensor is mounted by which the three components of magnetic field fluctuations are measured. During the AUG discharges the probe head is inserted up to three times for 100 ms each by the midplane manipulator into the scrape-off layer.