First acceleration of heavy ion beams with a superconducting continuous wave HIM/GSI CW-linac

M Basten,A Schnase,T Kürzeder,M Miski-Oglu,S Lauber,W Barth,F Dziuba,S Yaramyshev,M Schwarz,V Gettmann,M Busch,A Rubin,K Aulenbacher,M Heilmann,H Podlech

doi:10.1088/1742-6596/1401/1/012012

Abstract

In the future a new superconducting (sc) continuous wave (cw) high intensity heavy ion Linac should provide ion beams with a max. beam energy above the coulomb barrier for the Super Heavy Element (SHE) program at GSI Helmholtzzentrum für Schwerionenforschung. Key features of this new Linac are the acceleration of different ions from protons to uranium as well as a smooth energy variation from 3.5 to 7.3 MeV/u for design ions with a mass-to-charge ratio A/q = 6 and even above for lighter ions. As a first step a newly developed superconducting 15-gap Crossbar H-cavity (CH-cavity) operated at 217 MHz has been successfully tested with heavy ion beam up to the design beam energy of 1.85 MeV/u for the first time. The design energy gain of 3.5 MV within a length of less than 70 cm has been validated with heavy ion beams of up to 1.5 pμA. The measured beam parameters showed excellent beam quality, while a dedicated beam dynamics layout provides beam energy variation between 1.2 and 2.2 MeV/u. The beam commissioning is a milestone of the R&D work of Helmholtz Institute Mainz (HIM) and GSI in collaboration with Goethe University Frankfurt (GUF) and the first step towards a sc heavy ion cw-Linac with variable beam energy. The first tests under cryogenic conditions of the next two CH-cavities have already been started at GUF in a vertical cryostat. The results of the first successful heavy ion beam acceleration with a superconducting CH-cavity will be presented.

Highlights

Linac, as well as progress in elaboration of the superconducting technology [3] is of high relevance.For the Helmholtz Institute Mainz (HIM)/GSI cw-Linac HELIAC (HElmholtz LInear ACcelerator) several superconducting CH cavities operated at 217 MHz should provide for ion acceleration to beam energies between 3.5 MeV/u and 7.3 MeV/u, while the energy spread should be kept smaller than ±3 keV/u
For the HIM/GSI cw-Linac HELIAC (HElmholtz LInear ACcelerator) several superconducting CH cavities operated at 217 MHz should provide for ion acceleration to beam energies between 3.5 MeV/u and 7.3 MeV/u, while the energy spread should be kept smaller than ±3 keV/u
An advanced cw-Linac approach, based on a standard cryomodule equipped with three CH-cavities and a sc-rebuncher, demonstrates the high capabilities due to energy variation preserving the beam quality, as shown in the first beam test

Summary

Introduction

For the HIM/GSI cw-Linac HELIAC (HElmholtz LInear ACcelerator) several superconducting CH cavities operated at 217 MHz should provide for ion acceleration to beam energies between 3.5 MeV/u and 7.3 MeV/u, while the energy spread should be kept smaller than ±3 keV/u. In a preparing beam test run, it could be confirmed, that the room temperature focusing quadrupoles (triplet and two duplets) and two rebuncher cavities are sufficient to provide for full 6Dmatching to the demonstrator [17].

Results

Conclusion