FRIB, East Lansing, USA
JLab, Newport News, Virginia, USA
INFN/LNL, Legnaro (PD), Italy
KEK, Ibaraki, Japan
BNL, Upton, Long Island, New York, USA
ANL, Argonne, Illinois, USA
TRIUMF, Vancouver, Canada
Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 and the National Science Foundation under Cooperative Agreement PHY-1102511.
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
FRIB, East Lansing, USA
The Facility of Rare Isotope Beams (FRIB) at Michigan State University is now under construction toward user operation in year 2020. Charge-state transition of accelerating ions occurs in the beam line due to interaction with the residual gas. Since this exchange changes charge to mass ratio of the ions, the ion orbit is distorted especially in an arc section with the ion potentially hitting the vacuum pipe. This will generate outgassing from the beamline pipe. Moreover, they become a seed of further charge-state exchanges. Therefore, a collimation of charge exchanged ions is necessary to prevent this feedback cycle. In this presentation, the results of a simulation study on charge exchange reaction in the 1st arc section of FRIB and optimization of collimator position are presented.
FRIB, East Lansing, USA
We observed the outside magnetic field of the first β=0.085 production cryomodule while a solenoid and steering dipoles are under operation. This measurement aims to check the polarity on these magnets after the final installation in the accelerating tunnel. This paper also shows the residual magnetic field variation through the degaussing process of these magnets.
NSCL, East Lansing, Michigan, USA
BNL, Upton, Long Island, New York, USA
FRIB, East Lansing, USA
Modern ion accelerators, particularly heavy ion accelerators, almost universally make use of charge stripping. A challenge facing facilities, as the demand for higher intensity beams rises, is a stripping media that's highly resistant to degradation, such as a recirculating He gas stripper. A method of keeping the He gas localized in a segment along the beamline by means of a Plasma Window (PW) positioned on both sides of the gas stripper has been proposed and the initial design set forth by Ady Hershcovitch. With a cascaded plasma arc being the interface between high pressure stripper and low pressure beamline, the goal is to minimize gas flowrate from the stripper to the beamline in order to maintain sufficient isolation of the He gas. We present the initial results from the test stand developed at Michigan State University and the planned experimental program that will follow.
