Laboratory for High Energy Physics (LHEP)

The Bern medical cyclotron and its beam line

The Bern cyclotron laboratory features:

  • Cyclotron: IBA Cyclone 18/18 
  • Proton beams at 18 MeV
  • Current from few pA to 150 uA
  • 8 exit ports for targets/Beam Transfer Line
  • Targets: 4 liquid targets for routine F-18 production and one solid target station
  • Daily production of F-18 FDG and other radiopharmaceutical compounds, by SWAN Isotopen AG
  • Beam Transfer Line (BTL) for research purposes: 6.5-m long, 2 steering magnets, 2 quadrupole doublets, research bunker with independent access
  • Radioisotopes produced: F-18 (industrial production); Sc-44, Sc-43, Ga-68, Cu-61, Cu-64, Tb-155, V-48, Pm-x, Er-165, Tm-165 (research)

 

The beam

The cyclotron’s ion source is supplied by a bottle of hydrogen.  The H2 molecules are subjected to an electrical arc and form a plasma, from which negatively charged H- ions can be extracted and accelerated inside the cyclotron.   When the ions reach their maximum energy inside the cyclotron, they pass through a stripper foil that traps their electrons and causes them to become positively charged protons. The stripper foil is positioned such that the protons are redirected to the desired exit port, to be used for research or for isotope production.

Cyclotron laboratory layout at SWAN in Insel Spital
Layout of the cyclotron laboratory. The facility features two independent bunkers: the main bunker with the cyclotron, and a second one where physics experiments can be conducted by means of the Beam Transfer Line. The physics lab and the workshop are located inside the controlled area.

 

The Beam Transfer Line 

The Beam Transfer Line (BTL) is a key feature of the Bern medical cyclotron. It is used to transfer the proton beam from the main bunker, where the cyclotron is located, to a separate, independently accessible bunker, where research activities are conducted.

View of the inside of the cyclotron bunker
The cyclotron bunker. On the right, the Beam Transfer Line (BTL) delivers the beam to the separate bunker, used for research.
Beam Transfer Line
The Beam Transfer Line, seen from the research bunker, with an ongoing experiment.

 

Selected publications 

S. Braccini, The new Bern PET cyclotron, its research beam line, and the development of an innovative beam monitor detector, AIP Conference Proceedings, vol. 1525, p. 144–150, 2013; https://doi.org/10.1063/1.4802308

S. Braccini, A. Ereditato, P. Scampoli, K. Von Bremen, The New Bern Cyclotron Laboratory for Radioisotope Production and Research, Proceedings of the IPAC2011, San Sebastian, Spain, 4–9 September 2011; https://inspirehep.net/literature/1182673