title: Neutral beam dump with cathodic arc titanium gettering.
abstract: An incomplete neutral beam capture can degrade the plasma performance in neutral beam driven plasma machines. The beam dumps mitigating the shine-through beam recycling must entrap and retain large particle loads while maintaining the beam-exposed surfaces clean of the residual impurities. The cathodic arc gettering, which provides high evaporation rate coupled with a fast time response, is a powerful and versatile technique for depositing clean getter films in vacuum. A compact neutral beam dump utilizing the titanium arc gettering was developed for a field-reversed configuration plasma sustained by 1 MW, 20-40 keV neutral hydrogen beams. The titanium evaporator features a new improved design. The beam dump is capable of handling large pulsed gas loads, has a high sorption capacity, and is robust and reliable. With the beam particle flux density of 5 × 10(17) H∕(cm(2) s) sustained for 3-10 ms, the beam recycling coefficient, defined as twice the ratio of the hydrogen molecular flux leaving the beam dump to the incident flux of high-energy neutral atoms, is ∼0.7. The use of the beam dump allows us to significantly reduce the recycling of the shine-through neutral beam as well as to improve the vacuum conditions in the machine.
authors: Tri Alpha Energy Inc., Rancho Santa Margarita, California 92688, USA. asmirnov@trialphaenergy.com
authors: A
authors: A
authors: Smirnov
authors: A S
authors: AS
authors: Krivenko
authors: S V
authors: SV
authors: Murakhtin
authors: V Ya
authors: VY
authors: Savkin
authors: S A
authors: SA
authors: Korepanov
authors: S
authors: S
authors: Putvinski