Runaway electrons transport studies in the HL-1M

The transport of runaway electrons in hot plasma can be measured by four experiments, which provide runaway electron diffusivity Dr. First experiment obtained runaway electrons using a steady state approach for values of the runaway confinement time τr deduced from hard X-ray (HXR) Bremsstrahlung spectra, in the second experiment, diffusion can be interpreted in terms of a magnetic fluctuation, from which an electron thermal diffusivity can be deduced. The runaway electron diffusion coefficient is determined by intrinsic magnetic fluctuations rather than electrostatic fluctuations because of the high energy involved. The results presented here demonstrate the efficiency of using runaway transport techniques for determining intrinsic magnetic fluctuations