Speaker
Mr
Magomedrizy Atlukhanov
(Budker INP SB RAS)
Description
Atomic powerful sources will be used as a source of heating of the plasma in future fusion reactors. To achieve high power efficiency of neutral injection the target with high neutralization coefficient is necessary in such systems. Currently, the main approach to neutralize the ion beams is to use a gas target, the effectiveness of which at high energies (1 MeV) does not exceed 60%. In addition these approaches significantly affect the vacuum conditions and the appearance of impurities in the beam. A possible solution to the transformation of the negative ion beam to atomic one with high efficiency without flaws is a "photon trap", as the basic process of this method is based on the photodetachment of an electron from a negative ion. The use of the mechanism allows neutral atoms yield to reach 100%.
Photon storage trap is designed as a system of parallel placed mirrors 25 cm long, consisting of individual cylindrical and spherical mirrors with a characteristic transverse dimension of 50 mm and a radius of curvature of 250 mm. The effectiveness of this approach is mainly determined by the quality of the reflecting surface. It is practically independent from the quality of the injected radiation and does not require high precision alignment of optical elements. In such a system the photons undergo multiple reflections.
This paper presents the results of research photoneutralization beams of negative ions of hydrogen and deuterium at the experimental stand. Experiments were carried out using an injector with a beam energy 6-12 keV and a current of 1 A, the laser power up to 2 kW. Neutralization coefficient obtained for negative hydrogen ions is $\sim$90% and $\sim$95% for deuterium. Experiments to determine the dependence of the beam neutralization factor on the laser power to the target have been carried out.
These results demonstrate the high efficiency of this method and opportunities of the photon detachment target for powerful beams of negative ions neutralization.
Primary author
Mr
Magomedrizy Atlukhanov
(Budker INP SB RAS)
Co-authors
Prof.
Aleksandr Burdakov
(Budker INP SB RAS)
Dr
Alexander Ivanov
(Budker INP SB RAS)
Mr
Alexandr Kasatov
(Budker INP SB RAS)
Mr
Anton Kolmogorov
(Budker INP SB RAS)
Mr
Maria Ushkova
(Novosibirsk State University, Novosibirsk, Russia)
Mr
Roman Vakhrushev
(Budker INP SB RAS)
Dr
Sergey Popov
(Budker INP SB RAS)
