PT Journal AU Zhang, J Illy, S Gr Pagonakis, I Avramidis, KA Thumm, M Jelonnek, J TI Influence of emitter surface roughness on high power fusion gyrotron operation SO Nuclear fusion PY 2016 BP 026002/1 EP 7 VL 56 IS 2 DI 10.1088/0029-5515/56/2/026002 LA english ER