Results of beam tests on a high current EBIS test stand
At Brookhaven National Laboratory there is an R&D program to design an Electron Beam Ion Source (EBIS) for use in a compact ion injector to be developed for the Relativistic Heavy Ion Collider (RHIC). The BNL effort is directed at developing an EBIS with intensities of 3/spl times/10/sup 9/ particles/pulse of ions such as Au/sup 35+/ and U/sup 45+/, and requires an electron beam on the order of 10 A. The construction of a test stand (EBTS) with the full electron beam power and 1/3 the length of the EBIS for RHIC is nearing completion. Initial commissioning of the EBTS was made with pulsed electron beams of duration <1 ms and current up to 13 A. Details of the EBTS construction, results of the pulse tests, and preparations for DC electron beam tests are presented.
SIMULATION OF 10 A ELECTRON-BEAM FORMATION AND COLLECTION FOR A HIGH CURRENT ELECTRON-BEAM ION SOURCE
Presented is a report on the development of an electron-beam ion source (EBIS) for the relativistic heavy ion collider at Brookhaven National Laboratory (BNL) which requires operating with a 10 A electron beam. This is approximately an order of magnitude higher current than in any existing EBIS device. A test stand is presently being designed and constructed where EBIS components will be tested. It will be reported in a separate paper at this conference. The design of the 10 A electron gun, drift tubes, and electron collector requires extensive computer simulations. Calculations have been performed at Novosibirsk and BNL using two different programs, SAM and EGUN. Results of these simulations will be presented.
Ultra high vacuum technology applied for the design of warm EBIS or EBIT ion sources
Abstract The important feature in the Electron Beam Ion Source (EBIS) or Electron Beam Ion Trap (EBIT) design is the low vacuum pressure ( −9 Pa) required in the main part of the source to obtain an intense highly charged ion beam. Until now, the best sources used cryogenic pumping which does, however, present drawbacks: formation of cryosorbats and an important cryogenic dead time prior to each intervention inside the source. The vacuum pumping technology applied to accelerators and storage rings such as MIMAS at the Saturne National Laboratory has been adopted, enabling the achievement of very low pressure. This technology uses different types of pumps such as the high compression turbomolecular pump and titanium sublimators. This paper reports the results achieved in an ion source prototype, where the pressure is lower than 8 × 10 −10 Pa and the main residual gas is hydrogen. The vacuum chamber is made of stainless steel in which the electron gun cathode is heated to a nominal operating temperature (1100 °C). A gas can be injected (argon 2.6 × 10 −8 Pa) over a period of several days to create the working ions. After injection the initial pressure and the quality of the residual gas are recovered within a few hours.