Article

Experimental results of an electron cyclotron resonance oxygen source and a low energy beam transport system for 1 MeV integral split ring radio frequency quadruple accelerator upgrade project.

State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China.
Review of Scientific Instruments (Impact Factor: 1.6). 03/2008; 79(2 Pt 2):02B706. DOI: 10.1063/1.2802200
Source: PubMed

ABSTRACT To meet the requirements of developing separated function radio frequency quadruple (rfq) and upgrading the 1 MeV integral split ring rfq accelerator, an electron cyclotron resonance O(+) ion source and low energy beam transport (LEBT) system have been developed. Using two Einzel lenses to focus the beam, more than 6 mA O(+) peak beam current with energy of 22 keV can be easily obtained at the end of LEBT when the duty faction is at 1/6. The normalized root-mean-square emittance of 90% of the beam is about 0.12pi mm mrad. By changing the focusing power of lenses, the beam waist can be shifted from 80 mm before the beam diaphragm 2 to 80 mm after it. The experimental results will be presented in this article.

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