NSCL, East Lansing, Michigan
Funding: Work was supported by DOE grant DE-FG02-04ER41324
The proposed Facility for Radioactive Ion Beams (FRIB)* will deliver up to 400 kW of any stable isotope to multi-target experimental complex. Operational efficiency will be best served by a system that can distribute the beam current, variable in a large dynamic range, to several independent targets simultaneously. The proposed FRIB Beam Switchyard (BSY) utilizes an rf kicker with subsequent magnetostatic septum system to split the beam on micro-bunch to micro-bunch basis. The micro-bunches can be differentially loaded at the front-end of the Driver Linac**. The detailed analysis of the beam dynamics performance in the proposed BSY system is presented.
*D.Gorelov, et al, proc of EPAC 2002, Paris, France, 2002.
**M. Doleans, et al, LINAC 2006, Knoxville, TN, USA, 2006.
SAIC, Los Alamos, New Mexico
LANL, Los Alamos, New Mexico
LLNL, Livermore, California
NSTec, Los Alamos, New Mexico
Voss Scientific, Albuquerque, New Mexico
The DARHT-II accelerator produced a 2 kA, 17 MeV beam over a 1600 ns flattop. After exiting the accelerator, the long pulse is sliced into four short pulses by a kicker and quadrupole septum and then transported and focused on a target for conversion to bremsstrahlung for radiography. We describe the initial commissioning tests of the kicker, septum, transport, and multi-pulse converter target. The results of beam measurements made during the commissioning of the accelerator downstream transport are described. Beam optics simulations of the commissioning results are described.
RAS/INR, Moscow
For intense proton beam acceleration the structure aperture diameter should be ~30 mm. With such aperture room temperature coupled cell accelerating structures have the maximal effective shunt impedance Ze at operating frequency ~650 MHz. For this frequency well known Side Coupled Stricture (SCS), Disk and Washer Structure (DAW), Annular Coupled Structure (ACS) have large transversal dimension, leading to essential technological problems. The Cut Disk Structure (CDS) has been proposed to join high Ze and coupling coefficient kc values, but preferably for high energy linacs. In this report parameters of the four windows CDS option are considered at operating frequency ~700 MHz for proton energy range from 80 MeV to 200 MeV. The cells diameter ~30 cm and kc ~0.12 result naturally, but Ze value is of (0.7-0.9) from Ze value for SCS (kc=0.03). Small cells diameter opens possibility of CDS applications for twice lower frequency and structure parameters at operating frequency ~ 350 MHz are estimated too. Cooling conditions for heavy duty cycle operation are considered.