Speaker
Description
The Facility for Rare Isotope Beams, FRIB, is being implemented at Michigan State University (MSU). One-part of FRIB is the ReA post-accelerator, which includes an Electron Beam Ion Trap (EBIT) charge breeder. Currently, RIB are produced by fast-projectile fragmentation and fission in the Coupled-Cyclotron Facility (CCF). After production, these beams are then separated in-flight and thermalized in a helium gas cell before being transported to ReA for reacceleration up to several MeV/u for the nuclear physics program. After the CCF-to-FRIB transition, the production yield of rare isotopes will significantly increase. In some cases, rates are expected to exceed 1010 particles/s (pps). In addition, the user community for the Separator for Capture Reactions (SECAR) recoil separator has requested stable-isotope ion beams with rates up to 1010 pps.
The ReA EBIT has a limited charge capacity of 1010 elementary (1+) charges, which is insufficient to efficiently charge breed RIB of high rates from FRIB to high charge states. To increase the charge capacity of the ReA charge breeder, a new High Current Electron Beam Ion Source (HCEBIS) is being constructed. The HCEBIS uses the “backbones” of the TEST EBIS, which was transferred from the Brookhaven National Laboratory (BNL) in 2018. The HCEBIS can operate with an electron-beam current exceeding 4 A, allowing the device to deliver highly charged ion beams of intensities expected to be more than 1010 ions per second. In this contribution, the status of the HCEBIS will be presented. The currently installed LaB6 cathode was tested to an emission current of 1.12 A without magnets in a test configuration. Electron-beam transport simulations were performed from cathode to collector. The emittance of extracted beams was simulated. Moreover, this contribution will also present measurements of the charge capacity of the ReA EBIT in the continuous injection mode that were taken during beam tests to provide intense beams before the installation of the HCEBIS. These measurements can be used to determine through extrapolation the expected charge capacity of the HCEBIS.