IMP, Lanzhou
CSR is a new ion cooler-storage-ring system in China IMP, it consists of a main ring (CSRm) and an experimental ring (CSRe). The two existing cyclotrons of the Heavy Ion Research Facility in Lanzhou (HIRFL) are used as its injector system. The heavy ion beams from the cyclotrons are injected first into CSRm for accumulation with e-cooling and acceleration, finally extracted fast to CSRe for internal-target experiments and mass measurements of radioactive ion beams (RIBs), or extracted slowly for external-target experiments or cancer therapy. In 2005 the CSR construction was completed and the commissioning finished in the past three years. It includes stripping injection (STI), electron-cooling with hollow electron beam, C-beam stacking with the combination of STI and e-cooling, wide energy-range acceleration from 7 MeV/u to {10}00 MeV/u with the RF harmonic-number changing, multiple multi-turn injection (MMI) and beam accumulation with MMI and e-cooling for heavy-ion beams of Ar, Kr and Xe, fast and slow extraction from CSRm, the commissioning of CSRe with two lattice modes, and a RIB mass-spectrometer test with the isochronous mode in CSRe by the time-of-flight method.
ORNL, Oak Ridge, Tennessee
Muons, Inc, Batavia
JLAB, Newport News, Virginia
Funding: Supported in part by USDOE Contract No. DE-AC05-84-ER-40150. Supported in part by USDOE Contract DE-AC05-00OR22725
The ORNL spallation neutron source (SNS) user facility requires a reliable, intense beams of protons. The technique of H- charge exchange injection into a storage ring or synchrotron has the potential to provide the needed beam currents, but it will be limited by intrinsic limitations of carbon and diamond stripping foils. A laser in combination with magnetic stripping has been used to demonstrate a new technique for high intensity proton injection, but several problems need to be solved before a practical system can be realized. Technology developed for use in Free Electron Lasers is being used to address the remaining challenges to practical implementation of laser controlled H- charge exchange injection for the SNS. These technical challenges include (1) operation in vacuum, (2) the control of the UV laser beam to synchronize with the H- beam and to shape the proton beam, (3) the control and stabilization of the Fabry-Perot resonator, and (4) protection of the mirrors from radiation.
ORNL, Oak Ridge, Tennessee
BINP SB RAS, Novosibirsk
Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
A transverse phase space emittance scanner is proposed and under development for the 1-GeV H- SNS linac, using a laser beam as a slit. For a 1 GeV H- beam, it is difficult to build a slit because the stopping distance is more than 50 cm in copper. We propose to use a laser beam as an effective slit by stripping off the outer electron of the H- (making it neutral) upstream of a bend magnet and measuring the stripped component downstream of the bend magnet. The design and modeling of the system will be discussed. We are expecting to make a preliminary measurement in 2009.
ORNL, Oak Ridge, Tennessee
Funding: *Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.
HRIBF produces high-quality beams of short-lived radioactive isotopes for nuclear science research, and is currently unique worldwide in the ability to provide neutron-rich fission fragment beams post-accelerated to energies above the Coulomb barrier. HRIBF is undergoing a multi-phase upgrade. Phase I (completed 2005) was construction of the High Power Target Laboratory to provide the on-going Isotope Separator On-Line development program with a venue for testing new targets, ion sources, and radioactive ion beam (RIB) production techniques with high-power ORIC beams. Presently under way is Phase II, the Injector for Radioactive Ion Species 2, a second RIB production station that will improve facility reliability and accommodate new ion sources, RIB production, and RIB purification techniques, including laser applications. The Phase III goal is to substantially improve facility performance by replacing or supplementing the Oak Ridge Isochronous Cyclotron production accelerator with either a high-power 25-50 MeV electron accelerator or a high-current multi-beam commercial cyclotron. Either upgrade is applicable to R&D on isotope production for medical or other applications.