Spatially and temporally resolved measurements of runaway electrons in the TEXTOR tokamak

Spatially and temporally resolved measurements of runaway electrons have been performed in the TEXTOR tokamak by means of synchrotron emission, neutron detectors and with a newly installed scanning probe, located at different radial positions. The main element of the probe is a fluorescing crystal, which is covered by a graphite housing. The generation of runaway electrons inside the plasma was observed with synchrotron measurements and an exponential decay of the runaway electron population at the plasma boundary was measured with the probe. In the next step the probe has been upgraded to measure an energy spectrum by using several crystals separated by tungsten filters. At the plasma density of 1.2.1019 m-3 runaways with a narrow energy distribution between 3 MeV and 8 MeV has been measured