Open AccessHigh Power Density Beam Measurement of a Single Beamlet Multi-Grid Prototype H- Negative Ion Accelerator
Author(s) -
G. Q. Saquilayan,
M. Kisaki,
Akira Kojima,
Yuji Shimabukuro,
Masamichi Murayama,
Junichi Hoshino,
Masahiro Ichikawa,
K. Watanabe,
H. Tobari,
M. Kashiwagi
Publication year - 2022
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2244/1/012091
Subject(s) - perveance , thermal emittance , beam (structure) , beam divergence , optics , physics , beam emittance , beam diameter , linear particle accelerator , ion beam , nuclear physics , cathode ray , electron , laser , laser beams
Beam optics of the ITER prototype accelerator with 88 mm acceleration gap length has been examined through H - beam acceleration tests at the ITER target beam perveance. The beam optics has been examined for beam energies up to 790 keV under the ITER target perveance. The total grid heat load was successfully reduced to 10 %, which was lower than the allowable value of 15 %. The beam emittance of the ITER perveance has been measured for the first time by using newly developed emittance measurement system consisting of carbon-fiber-composite (CFC) plate with pin-holes. The emittance of 790 keV H - beam shows the divergence angle of the beam core is satisfied with the ITER requirement of <7 mrad. Measurement at the beam periphery was made possible by modifying the pin-hole size of pepper-pot apertures, and the observed divergent components were 20 mrad. The ratio of the diverged beam became lower with the increase of the beam energy. This result contributes the design of the ITER accelerator and the beam line components.