Surface treatment of HV electrodes for superconducting cyclotron beam extraction

摘要: At the Istituto Nazionale di Fisica Nucleare Laboratorio del Sud of Catania, a K=800 superconducting cyclotron is in operation since 1994. The accelerator beam extraction accomplished using electrostatic deflectors constituted by HV electrodes generating electric fields to 140 kV/cm 6 8 mm gaps. performance strongly dependent on presence high magnetic (up 5 T) and ion energy intensity heavy beams. behavior these systems mainly determined field electron emission effects cathode surface, focalization processes due heating A detailed study under development starting with point, characterization electrode surface vs. material used (Ti, Cu, stainless steel, etc.) best mechanical chemical treatment available, Moreover, we are studying titanium surfaces nitriding over wide temperature range (300 800/spl deg/C). Preliminary results concerning use thermal processed polished presented discussed.