IAP, Frankfurt am Main
The Frankfurt Neutron source FRANZ is under construction*. The ARMADILLO bunch compressor** as a part of it is composed of a 5MHz electric kicker, a magnetic dipole chicane and rf-rebunching cavities. The design phase of the bunch compressor has reached the final stage. A 175MHz 2MeV proton linac forms 100ns long beam pulses consisting of nineμbunches with 150mA. Deflected by the 5MHz kicker theμbunches are guided on different paths to arrive within 1ns at a n-production target. Due to high space charge forces rebuncher cavities are included***. The peak current at the target is expected to be in the range of 10A in a 1ns proton pulse, which is equivalent to a longitudinal pulse compression ratio of 45. A new code specific for complex magnetic multi aperture system and for high current applications has been developed. Hardware designs according to the beam dynamics results are in progress. Improved 3D magnetic and electric fields will be applied in the future beam dynamics studies including high space charge forces. The preliminary designs and the beam dynamics studies will be presented in this contribution.
* O. Meusel, et al.: LINAC06, Knoxville, Tennessee USA, 2006, pp. 159-161.
** L. P. Chau, et al.: EPAC08, Genoa, Italy, 2008, pp. 3578-3580.
*** D. Noll, another contribution at this conference.
IAP, Frankfurt am Main
The Frankfurt Neutron Source (FRANZ) currently under construction at IAP (Goethe University of Frankfurt) is designed to produce short neutron pulses at high intensity and repetition rates up to 250 kHz [*]. To achieve a bunch length of one nanosecond despite the high space charge forces, a bunch compressor of the Mobley type [**] using four dipole magnets and two rebunchers has been developed [***] to merge 9 linac bunches into the final focus. The first rebuncher cavity, a λ/4 resonator operating at 87.5 MHz, has to feature nine beam paths due to the multi-trajectory system. Additionally the gaps have to be displaced relatively to each other in a way that all bunches arrive at the correct rf phase. The second rebunching cavity will provide final focusing as well as an energy variation of ±0.2 MeV in front of the target and will be operating at 175 MHz. This paper presents the design of these novel cavities as well as the simulated beam dynamic properties.
* Meusel et al., LINAC 2006
** Mobley, Phys. Rev. 88(2), 360-361 (1951)
*** Chau et al, LINAC 2010
IAP, Frankfurt am Main
The Frankfurt Neutron source FRANZ is under construction*. The ARMADILLO bunch compressor** as a part of it is composed of a 5MHz electric kicker, a magnetic dipole chicane and rf-rebunching cavities. The design phase of the bunch compressor has reached the final stage. A 175MHz 2MeV proton linac forms 100ns long beam pulses consisting of nineμbunches with 150mA. Deflected by the 5MHz kicker theμbunches are guided on different paths to arrive within 1ns at a n-production target. Due to high space charge forces rebuncher cavities are included***. The peak current at the target is expected to be in the range of 10A in a 1ns proton pulse, which is equivalent to a longitudinal pulse compression ratio of 45. A new code specific for complex magnetic multi aperture system and for high current applications has been developed. Hardware designs according to the beam dynamics results are in progress. Improved 3D magnetic and electric fields will be applied in the future beam dynamics studies including high space charge forces. The preliminary designs and the beam dynamics studies will be presented in this contribution.
