Study of the time and space distribution of beta+ emitters from 80 MeV/u carbon ion beam irradiation on PMMA

Abstract

Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments and the on-line knowledge of the Bragg peak position is still a matter of research. A possible technique exploits the collinear $511\ \kilo\electronvolt$ photons produced by positrons annihilation from ${\beta }^{+}$ emitters created by the beam. This paper reports rate measurements of the $511\ \kilo\electronvolt$ photons emitted after the interactions of a $80\ \mega\electronvolt / u$ fully stripped carbon ion beam at the Laboratori Nazionali del Sud (LNS) of INFN, with a Poly-methyl methacrylate target. The time evolution of the ${\beta }^{+}$ rate was parametrized and the dominance of ${}^{11}C$ emitters over the other species (${}^{13}N$, ${}^{15}O$, ${}^{14}O$) was observed, measuring the fraction of carbon ions activating ${\beta }^{+}$ emitters $A_0=(10.3\pm 0.7)\cdot 10^{-3}$. The average depth in the PMMA of the positron annihilation from ${\beta }^{+}$ emitters was also measured, $D_{β^+}=5.3\pm1.1\ \milli\meter$, to be compared to the expected Bragg peak depth $D_{Bragg}=11.0\pm 0.5\ \milli\meter$ obtained from simulations.

References in corpus (3)

• The physics models of FLUKA: status and recent development
• Distributions of positron-emitting nuclei in proton and carbon-ion therapy studied with GEANT4
• Precise measurement of prompt photon emission for carbon ion therapy

Cited by in corpus (4)

• Charged particle's flux measurement from PMMA irradiated by 80 MeV/u carbon ion beam
• Secondary radiation measurements for particle therapy applications: prompt photons produced by ${}^4$He, ${}^{12}$C and ${}^{16}$O ion beams in a PMMA target
• Extended calibration range for prompt photon emission in ion beam irradiation
• Secondary radiation measurements for particle therapy applications: Charged secondaries produced by 4He and 12C ion beams in a PMMA target at large angle