Author: Heilmann, M.
Paper Title Page
MO3A03 FRANZ – Accelerator Test Bench and Neutron Source 130
  • O. Meusel, L.P. Chau, M. Heilmann, H. Podlech, U. Ratzinger, K. Volk, C. Wiesner
    IAP, Frankfurt am Main, Germany
  The challenge of existing and planned neutron sources is to provide highly brilliant ion beams with high reliability. The Frankfurt neutron source FRANZ is not only a neutron source but also a test bench for novel accelerator and diagnostic concepts for intense ion beams. The experiment consists of a compact linear accelerator test bench for the acceleration of an intense proton beam to 2 MeV producing the neutrons via the 7Li(p,n) reaction. The final beam intensity will be 200 mA, therefore the space charge and space charge compensation effects can be studied with high statistical relevance along the accelerator. The low energy beam transport LEBT is equipped with four solenoids matching the beam into the chopper system and into the RFQ-IH combination already under construction. The coupling of the RFQ accelerator stage and the IH drift tube cavity offers the possibility to use only one power amplifier as a driver for both of these resonators and reduces investment costs. The compact design of this low-β accelerator stage is optimized for high beam intensities to overcome the strong space charge forces expected in this accelerator test bench.  
THPB008 A Coupled RFQ-IH Cavity for the Neutron Source FRANZ 858
  • M. Heilmann, O. Meusel, D. Mäder, U. Ratzinger, A. Schempp, M. Schwarz
    IAP, Frankfurt am Main, Germany
  The Frankfurt neutron source FRANZ will deliver neutrons in the energy range from 1 to 500 keV with high pulsed intensities. A 2 MeV proton beam will produce protons via the 7Li(p,n)7Be reaction. The 175 MHz accelerator cavity consists of a 4-rod-RFQ coupled with an 8 gap interdigital H-type drift tube section, the total cavity length being 2.3m. The combined cavity will be powered by one RF amplifier to reduce investment and operation costs. The inductive power coupler will be at the RFQ part. The coupling into the IH - section is provided through a large aperture - mainly inductively. By CST - MWS - simulations as well as by an RF - model the voltage tuning along the cavity was investigated, and with special care the balance between both cavity sections. A first set of RFQ electrodes should allow to reach beam currents up to 50 mA in cw operation: The beam is pulsed with 100 ns, 250 kHz, while the cavity has to be operated cw due to the high rep. rate. The layout of the cavity cooling aims on a maximum accessible heat load of 200 kW.