%0 Conference Paper
%A Ondreka, David
%A Bozyk, Lars
%A Graeff, Christian
%A Spiller, Peter
%A Stadlmann, Jens
%A Volz, Lennart
%Y Pilat, Fulvia
%Y Fischer, Wolfram
%Y Saethre, Robert
%Y Anisimov, Petr
%Y Andrian, Ivan
%T Slow extraction of a dual-isotope beam from SIS18
%I JACoW Publishing
%M GSI-2025-00401
%P 1698-1701 pages
%D 2024
%Z Published by JACoW Publishing under the terms of the Creative Commons Attribution 4.0 license.
%X Recently, the heavy ion synchrotron SIS18 at GSI was for the first time operated with a dual-isotope beam, made up of 12C3+ and 4He+. Such a beam can be used to improve carbon radiotherapy by providing online information on dose deposition, where the helium ions serve as a probe beam traversing the patient while depositing a negligible dose. For this, the accelerator has to deliver a slowly extracted beam with a fixed fraction of helium over the spill. The difference in mass-to-charge ratio of 4He compared to 12C is small enough to permit simultaneous acceleration and to make the two isotopes practically indistinguishable for the accelerator instrumentation. Yet, it may cause a temporal shift between the two components in the spill owing to the sensitivity of slow extraction to tiny tune variations. We investigated different extraction methods, and examined the time-wise stability of the dual-isotope beam with a beam monitoring setup installed in the GSI biophysics experiment room. A constant helium fraction was obtained using transverse knock-out extraction with adjusted chromaticity.
%B 15th International Particle Accelerator Conference
%C 19 May 2024 - 24 May 2024, Nashville (USA)
Y2 19 May 2024 - 24 May 2024
M2 Nashville, USA
%K Accelerator Physics (Other)
%K mc4-hadron-accelerators - MC4: Hadron Accelerators (Other)
%K MC4.A16 - MC4.A16 Advanced Concepts (Other)
%F PUB:(DE-HGF)8
%9 Contribution to a conference proceedings
%R 10.18429/JACOW-IPAC2024-TUPS29
%U https://repository.gsi.de/record/357444