Cross-section measurements are mandatory in the field of theranostics, where the suitable quantity and quality of the produced radionuclides is of the utmost importance.
A novel method has been developed at the Bern cyclotron, to improve nuclear data of production cross sections up to the maximum proton beam energy of 18 MeV. This procedure is based on the irradiation by an online-monitored flat beam and on the measurement of the current on target.
Specific target “coins” were conceived to contain foils or powder material compressed in pellets. The addition of passive absorbers allows for variation of the energy. A specific target station is used to perform the experiment using the Beam Transfer Line (BTL).
For cross-section measurements and for an optimised radioisotope production, the accurate knowledge of the beam energy is mandatory. Our group is developing several methods to assess this quantity, based on magnetic deflection and passive absorption of the beam. We studied the variation of the beam energy as a function of the main operational parameters of the cyclotron for the first time.
The cross section of several nuclear reactions has been measured at the Bern cyclotron, improving nuclear data. In particular, we measured the production cross section of Sc-43 and Sc-44, challenging but promising radioisotopes for theranostics.
We have performed a detailed study of the beam energy in the BTL as a function of the main operational parameters of the cyclotron. In particular, we have found a dependence as a function of the position of the stripper foil. Studies are ongoing to assess the beam energy on the exit port where the Solid Target Station is installed.
G. Dellepiane, C. Belver Aguilar, T. S. Carzaniga, P. Casolaro, P. D. Häffner, P. Scampoli, M. Schmid, S. Braccini, Research on theranostic radioisotope production at the Bern medical Cyclotron, Il Nuovo Cimento, 2021; DOI: 10.1393/ncc/i2021-21130-6
T. S. Carzaniga, M. Auger, S. Braccini, M. Bunk, A. Ereditato, K. Pawel Nesteruk, P. Scampoli, A.Türler, N. van der Meulen, Measurement of Sc-43 and Sc-44 production cross-section with an 18 MeV medical PET Cyclotron, App. Radiat Isot. 2017 Nov. 129:96-102; https://doi.org/10.1016/j.apradiso.2017.08.013
P. Häffner, C. Belver-Aguilar, S. Braccini, P. Scampoli, P. A. Thonet, Study of the Extracted Beam Energy as a Function of Operational Parameters of a Medical Cyclotron, Instruments 2019, 3(4), 63; https://doi.org/10.3390/instruments3040063