Conveners
Applications
- Jan Borburgh (CERN)
Conditioning experiment of a commercial vacuum interrupter was carried out with a gap distance of 1~3 mm. Energy of the vacuum arc following a breakdown has been controlled to be as low as several hundred mJ with a 100 kΩ current-limiting resistor. Breakdown voltage and field emission current was measured during the conditioning process. The Murphy-Good plot was employed to further study...
The design of the RFX-mod2 experimental fusion device requires a copper shell close to the plasma to aid in stability and magnetic confinement of the plasma [1,2]. This conductive structure, only 3mm thick, placed around the plasma, must have electrical discontinuities in both the poloidal and toroidal directions, so as to allow the penetration of electromagnetic fields into the plasma region....
Producing higher brightness beams at the cathode is one of the main focuses for future electron beam applications. For photocathodes operating close to their emission threshold, the cathode lattice temperature begins to dominate the minimum achievable intrinsic emittance. At UCLA, we are designing a radiofrequency (RF) test bed for measuring the temperature dependence of the mean transverse...
We find that a general vacuum arc model seems to require four stages: a trigger, ionization, plasma evolution, and surface damage. Within this framework, a large number of mechanisms operate, involving field emission, surface failure, ionization, plasma interactions with the surface and surface interactions with plasma. Field emission is complicated by the duty cycle, space charge, nearby...
Vacuum Arc Remelting (VAR) is typically the final melting process in the production of a wide range of metallic alloys. The process consists in applying during days a DC current of up to 40 000 A over large electrodes(~1m diameter). A strong DC arc takes place under vacuum between an electrode and a water-cooled copper crucible. For low applied current, high-speed video observation showed that...
