Emissive probes for edge plasma measurements in magnetized plasmas

摘要

The two most important parameters, whose knowledge is essential for understanding transport inthe edge region of a magnetised plasma, are plasma potential and, through it, electric field. How-ever,the determination of these parameters with sufficient accuracy, temporal and, in particular,spatial resolution, is not an easy task. Here we would like to give first a few basic considerationsabout emissive probes and then a short survey of our experiences with emissive probes for a directdetermination of the plasma potential and, by use of several emissive and cold probes, also of elec-tricfield components and more complex transport parameters in ISTTOK (Lisbon) and CASTOR(Prague). While for this purpose we used conventional emissive wire probes, a new type of laser-heatedemissive probe was used in VINETA in Greifswald to measure the plasma potential and itsfluctuations.