Design of an electron cooling device for the accumulator cooler ring in MUSES project

As a part of new experimental facility in the Radio Isotope Beam Factory (R IBF) project at RIKEN, the Multi-Use Experimental Storage rings (MUSES) hav e an Accumulator Cooler Ring (ACR) which is used for both the accumulation and cooling of RI beams and various experiments. Besides a stochastic coole r, an electron cooler (EC) is presently under development. The ion energy i n the ACR ranges from 60 to 400 MeV/u which corresponds to the electron bea m (e-beam) energy for the EC from 30 to 250 kV. The maximum current from a 12.7 mm cathode is 4.1 A with a gun perveance of 0.79 mu P. A superconducti ng solenoid in the gun section generates a magnetic field of 4 T which corr esponds to a factor of 20 in adiabatic expansion. The design issues of the gun section, collector, toroidal magnets and compensation solenoids are dis cussed in detail with some retrospection of the development. (C) 2000 Elsev ier Science B.V. All rights reserved.