Improvements on the LBL AECR source

Conference · Sat Apr 01 04:00:00 EST 1995

OSTI ID:95359

Xie, Z Q; Lyneis, C M

Performance of the LBL AECR source was improved by simultaneously heating the plasma with microwaves of 10 and 14 GHz (two-frequency heating). Plasma stability was improved.and the ion charge state distribution shifted to higher charge state. Production of high charge state ions was increased a factor of 2 to 5 or higher for the very heavy ions such as bismuth and uranium, as compared to the case of single-frequency (14 GHz) heating. Fully stripped argon ions at intensity I {ge} 5 enA were directly identified by the AECR charge state analyzing system for the first time. High charge state ion beams of bismuth and uranium produced by the source were injected into the 88-Inch Cyclotron. After acceleration to energies greater than 6 MeV/nucleon, the extracted beam intensities were 1{times}10{sup 6}pps or higher for Bi{sup 50+,51+} and {sup 238}U{sup 52+,53+}. Tests in the AECR source have also shown Al{sub 2}O{sub 3} coating is an effective coating and a better method than the electron gun for providing cold electrons to the ECR plasma. The AECR source will be upgraded to raise its magnetic field strengths to obtain better plasma confinement and enhanced production of hi ah charge state heavy ions.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 95359
• Report Number(s): LBL--37275; CONF-9504165--2; ON: DE95014771
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BROOKHAVEN CYCLOTRON
ION SOURCES
PERFORMANCE