LINAC 2006 - List of Authors (Ratzinger, U.)

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Ratzinger, U.

Paper	Title	Page
MOP051	Development of an Intense Neutron Source FRANZ in Frankfurt	159
	O. Meusel, L. P. Chau, I. Mueller, U. Ratzinger, A. Schempp, K. Volk, C. Zhang IAP, Frankfurt-am-Main S. Minaev ITEP, Moscow
	The Stern-Gerlach-Center recently founded at the University of Frankfurt gives the possibility for experiments in accelerator physic, astrophysic and material sience research. It is planned to develop an intense neutron generator within the next 4 years. The proton driver linac consists of a high voltage terminal already under construction to provide primary proton beam energies of max. 150 keV. A volume type ion source will deliver a DC beam current of 100-250 mA at a proton fraction of 90%. A low energy beam transport using two solenoids will inject the proton beam into an RFQ while a chopper at the entrance of the RFQ will create a pulse length of 50 ns and a repetition rate up to 250 kHz. A drift tube cavity for the variation of the beam energy in a range of 1.9 – 2.4 MeV will be installed downstream of the RFQ. Finally a bunch compressor of the Mobley type forms a proton pulse length of 1 ns at the Li target. The maximum energies of the neutrons being adjustable between 100 keV and 500 keV by the primary proton beam. The detailed concept of the high current injector, numerical simulation of beam transport and losses will be presented together with first experimental results.
MOP059	Long-Term Perspective for the UNILAC as a High-Current, Heavy-Ion Injector for the FAIR-Accelerator Complex	180
	W. Barth, L. A. Dahl, L. Groening, S. Yaramyshev GSI, Darmstadt U. Ratzinger IAP, Frankfurt-am-Main
	The present GSI-accelerator complex, consisting of the linear accelerator UNILAC and the heavy ion synchrotron SIS 18, is foreseen to serve as an U²⁸⁺-injector for up to 10⁺¹² particles/s for FAIR. In 2003 and 2004 different hardware measures and careful fine tuning in all sections of the UNILAC resulted in an increase of the beam intensity to 9.5·10⁺¹⁰ U²⁷⁺ ions per 100 mks (max. pulse beam power of 0.5 MW). In addition a dedicated upgrade program for the UNILAC will be performed until 2009. It is intended to fill the SIS 18 up to the space charge limit of 2.7·10⁺¹¹ U²⁸⁺ ions per cycle. After completion of the FAIR complex in 2015 the running time for the accelerator facility at least will be 20 years, while the UNILAC will then be in operation for more than 60 years as a high duty factor heavy ion linac. Different proposals for a new advanced short pulse, heavy ion, high intensity, high energy linac, substituting the UNILAC as a synchrotron injector, will be discussed. This new "High Energy-UNILAC" has to meet the advanced FAIR requirements, will allow for complete multi-ion-operation and should provide for reliable beam operation in the future.
MOP061	The 70-MeV Proton Linac for the Facility for Antiproton and Ion Research FAIR	186
	L. Groening, W. Barth, L. A. Dahl, W. Vinzenz, S. Yaramyshev GSI, Darmstadt G. Clemente, U. Ratzinger, A. Schempp, R. Tiede IAP, Frankfurt-am-Main
	A significant part of the experimental program at FAIR is dedicated to antiproton (pbar) physics requiring up to 7·10¹⁰ cooled pbars per hour. Taking into account the pbar production and cooling rate, this is equivalent to a primary proton beam of 2·10¹⁶ protons per hour to be provided by a 70 MeV proton linac preceding two synchrotrons. It has to deliver a pulsed proton beam of 70 mA of 36 μs duration at a repetition rate of 4 Hz. The normalized transverse emittances must not exceed 2.8 mm mrad and the total relative momentum spread must be less than 0.1%. The normal conducting DTL comprises 12 Crossed-bar H-cavities (CH) fed by six rf-power sources in total. The basic layout of the linac as well as the overall cost estimate has been completed including several reviews by external committees. A technical report has been completed in May 2006. This paper gives a general overview on the status of the project.
MOP063	Deceleration of Highly Charged Ions for the HITRAP Project at GSI	189
	O. K. Kester, W. Barth, L. A. Dahl, F. Herfurth, M. Kaiser, H. J. Kluge, C. Kozhuharov, W. Quint GSI, Darmstadt B. Hofmann, U. Ratzinger, A. C. Sauer, A. Schempp IAP, Frankfurt-am-Main
	The highly charged heavy ion trap (HITRAP) project at GSI is a funded mid term project and is planned to be operational end of 2007. Highly charged ions up to U⁹²⁺ provided by the GSI accelerator facility will be decelerated from 4 MeV/u down to 6 keV/u and subsequently be injected into a large Penning trap for further deceleration and phase space cooling. The deceleration is done in a combination of the GSI experimental storage ring (ESR) and a linac based on an IH-structure and a RFQ. In front of the decelerator linac a double drift-buncher-system provides for phase focusing and a final de-buncher integrated in the RFQ-tank reduces the energy spread in order to improve the efficiency for beam capture in the cooler trap. The paper reports the beam dynamics design along the entire decelerator down to the trap injection point, as well as and the status of the cavities. Finally the time schedule and ESR and linac commissioning are discussed.
MOP046	Commissioning of the 7-MeV/u, 217-MHz Injector Linac for the Heavy Ion Cancer Therapy Facility at the University Clinics in Heidelberg	148
	B. Schlitt, R. Baer, W. Barth, T. G. Fleck, M. Hoerr, G. Hutter, C. M. Kleffner, M. T. Maier, A. Peters, M. Schwickert, K. Tinschert, W. Vinzenz, H. Vormann, D. Wilms GSI, Darmstadt R. Cee, E. Feldmeier, B. Naas, S. Scheloske, J. Suhm, S. Vollmer, T. Winkelmann HIT, Heidelberg G. Clemente, U. Ratzinger, A. Schempp IAP, Frankfurt-am-Main S. Minaev ITEP, Moscow
	A clinical synchrotron facility designed by GSI for cancer therapy using energetic proton and ion beams (C, He and O) is under construction at the university clinics in Heidelberg, Germany. In this contribution the current status of the injector linac is reported. The installation and commissioning of the linac is performed gradually in three steps for the ion sources and the LEBT, the 400 keV/u RFQ and the 7 MeV/u IH-type drift tube linac. Two powerful 14.5 GHz permanent magnet ECR ion sources from PANTECHNIK as well as the LEBT and the linac RF system have been installed in Heidelberg between November 2005 and March 2006. A test bench with versatile beam diagnostics elements has been designed and installed for the commissioning phase. In April 2006 the two ion sources produced the first ion beams on the site. Extensive RFQ tests using proton beams have been performed at test benches at the IAP and at GSI already during 2004-2006. The 1.4 MW 217 MHz amplifier for the IH tank has also been commissioned at a test setup at GSI in advance to the installation in Heidelberg. The RF tuning of the 20 MV IH-DTL cavity is performed by the IAP in close cooperation with GSI.
TH1004	A 70-MeV Proton Linac for the FAIR Facility Based on CH - Cavities	526
	U. Ratzinger, G. Clemente, C. Commenda, H. Liebermann, H. Podlech, R. Tiede IAP, Frankfurt-am-Main W. Barth, L. Groening GSI, Darmstadt
	Future Accelerators for fundamental and for applied research will need a significant improvement in injector capabilities. This paper will describe the concept and the status of the 70 MeV, 70 mA proton injector for GSI - FAIR and compare the CH - linac design with traditional DTL concepts. Improvements in the space charge routine of the LORASR code as well as CH - prototype cavity development and cavity grouping with respect to commercial 3 MW rf power amplifiers is reported. Additionally, the potential of robust superconducting low and medium energy high current linac sections will be explained on the basis of experimental results from a first 19 cell s.c. 350 MHz CH - prototype cavity.
THP067	Status of the Tuner for the 19-Cell Superconducting CH Prototype Cavity	737
	C. Commenda, H. Liebermann, H. Podlech, U. Ratzinger, A. C. Sauer IAP, Frankfurt-am-Main K. Dermati GSI, Darmstadt
	The radio frequency tuning of the multi-cell superconducting CH structure for beta equal to 0.1 is investigated for a 19-cell niobium cavity operated at liquid helium temperature. By applying external mechanical forces the deformation of the structure is studied and the resulting change in frequency is analysed. The ruling equations of elasticity and the electromagnetic eigenvalue problem are solved by using commercial finite element tools. The quantitative results form the basis of an optimized tuning device. In order to guarantee a long lifetime of the cavity, fracture criteria are defined to avoid mechanical damage. Wherever possible the results are compared with experimental data obtained from measurements performed on the first CH prototype developed at the Institute of Applied Physics at Frankfurt. In addition a fast piezo device will be integrated into the slowly acting mechanical tuner. The whole system will operate in an existing horizontal cryostat for testing purposes.