Attempted RIAPMTQ Benchmarking Study of the ANL RIA Low-Beta LinacDesign

Billen, J. ; Qiang, J. ; Wangler, T.

关键词: 43;    ANL;    BEAM TRANSPORT;    CAVITIES;    DESIGN;    LANL;    LINEAR ACCELERATORS;    SIMULATION;    SOLENOIDS;   

DOI  :  10.2172/910322
RP-ID  :  LBNL--60086
RP-ID  :  CBP Note - 786
PID  :  OSTI ID: 910322
Others  :  R&D Project: 455401
Others  :  Other: BnR: KA1501020
Others  :  TRN: US0704156

美国|英语

来源: SciTech Connect

【 摘 要 】

The objective of this work is to compare the simulation results of the RIAPMTQ code with those of the ANL simulation code for the low-beta section of an ANL RIA Driver Linac design. However, the approach taken is not precisely that of a direct comparison of the two simulations of the same linac section, which is what one would normally expect to do. The reason is that the RFQ design approach used by the ANL codes and the LANL codes are approximately but not exactly the same, particularly at the ends of the RFQ, and it did not appear to be easy to make the two RFQ designs exactly identical. The effects on the beam of the different RFQ design approaches are not expected to be large, as long as the beam is properly matched at the transitions. What was done in the RIAPMTQ input file to compensate for the RFQ design difference was to use TRACE3D to adjust the four solenoid strengths and the two matching rf cavities in the MEBT (the beam transport system between the end of the RFQ and the beginning of the superconducting linac) to obtain the same match (Courant-Snyder parameters) into the superconducting linac as was obtained from the ANL code. We also matched the beam into the RFQ. The result is that we generate a RIAPMTQ input file for the low-beta section of the linac, which is not exactly identical to, but should be near to that of the ANL design. Then, what we wish to compare from the two codes are the rms emittances at the beginning of the superconducting linac, and the beam losses in the first or prestripper section of the superconducting (SC) linac. In this report, we describe the procedure and present the results. Section 2 gives the procedures and results, and Section 3 gives the summary.