Original paper| Volume 64, P45-53, August 2019

Secondary radiation measurements for particle therapy applications: Charged secondaries produced by 16O ion beams in a PMMA target at large angles


      • Therapeutic 16O beams interacting with a target produce abundant secondary radiation.
      • Production emission profiles, yields, and energy spectra were characterized experimentally at large angles.
      • 16O induced charged secondary particles can be exploited for radiotherapy range monitoring.
      • The sensitivity of the technique was explored in homogeneous and heterogeneous PMMA targets.
      • The collected data is essential to assess the range monitoring accuracy and resolution.


      Particle therapy is a therapy technique that exploits protons or light ions to irradiate tumor targets with high accuracy. Protons and 12C ions are already used for irradiation in clinical routine, while new ions like 4He and 16O are currently being considered. Despite the indisputable physical and biological advantages of such ion beams, the planning of charged particle therapy treatments is challenged by range uncertainties, i.e. the uncertainty on the position of the maximal dose release (Bragg Peak – BP), during the treatment. To ensure correct ‘in-treatment’ dose deposition, range monitoring techniques, currently missing in light ion treatment techniques, are eagerly needed.
      The results presented in this manuscript indicate that charged secondary particles, mainly protons, produced by an 16O beam during target irradiation can be considered as candidates for 16O beam range monitoring. Hereafter, we report on the first yield measurements of protons, deuterons and tritons produced in the interaction of an 16O beam impinging on a PMMA target, as a function of detected energy and particle production position. Charged particles were detected at 90° and 60° with respect to incoming beam direction, and homogeneous and heterogeneous PMMA targets were used to probe the sensitivity of the technique to target inhomogeneities. The reported secondary particle yields provide essential information needed to assess the accuracy and resolution achievable in clinical conditions by range monitoring techniques based on secondary charged radiation.


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Physica Medica: European Journal of Medical Physics
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Abou-Haidar Z.
        • et al.
        Performance of upstream interaction region detectors for the FIRST experiment at GSI.
        J Instrum. 2012; 7 (URL: P02006
        • Agodi C.
        • et al.
        Charged particle’s flux measurement from PMMA irradiated by 80 MeV/u carbon ion beam.
        Phys Med Biol. 2012; 57 (URL: 5667
        • Battistoni G.
        • et al.
        Design of a tracking device for on-line dose monitoring in hadrontherapy.
        Nucl Instrum Methods Phys Res Sect A. 2017; 845: 679-683
        • Bauer J.
        • Unholtz D.
        • Sommerer F.
        • Kurz C.
        • Haberer T.
        • Herfarth K.
        • Welzel T.
        • Combs S.E.
        • Debus J.
        • Parodi K.
        Implementation and initial clinical experience of offline pet/ct-based verification of scanned carbon ion treatment.
        Radiother Oncol. 2013; 107: 218-226
        • Boehlen T.
        • et al.
        The FLUKA code: developments and challenges for high energy and medical applications.
        Nucl Data Sheets. 2014; 120: 211-214
        • Durante M.
        • Orecchia R.
        • Loeffler J.S.
        Charged-particle therapy in cancer: clinical uses and future perspectives.
        Nat Rev Clin Oncol. 2017; 14 (483 EP –)
      1. Ferrari A, et al. FLUKA: A multi-particle transport code (program version 2005) Technical Report CERN-2005-10, INFN/TC 05/11, SLAC-R-773 Geneva; 2005.

        • Gaa T.
        • et al.
        Visualization of air and metal inhomogeneities in phantoms irradiated by carbon ion beams using prompt secondary ions.
        Physica Med. 2017; 38 (URL: 140-147
        • Gwosch K.
        • et al.
        Non-invasive monitoring of therapeutic carbon ion beams in a homogeneous phantom by tracking of secondary ions.
        Phys Med Biol. 2013; 58: 3755
        • Henriquet P.
        • et al.
        Interaction vertex imaging (IVI) for carbon ion therapy monitoring: a feasibility study.
        Phys Med Biol. 2012; 57: 4655-4669
        • Knopf A.C.
        • Lomax A.
        vivo proton range verification: a review.
        Phys Med Biol. 2013; 58: R131-R160
        • Kraan A.C.
        Range verification methods in particle therapy: underlying physics and monte carlo modeling.
        Front Oncol. 2015; 5: 150
        • Kraan A.C.
        • et al.
        First tests for an online treatment monitoring system with in-beam PET for proton therapy.
        J Instrum. 2014; 10
        • Krimmer J.
        • et al.
        Prompt-gamma monitoring in hadrontherapy: a review.
        Nucl Instrum Methods Phys Res Sect A. 2017; (URL:
        • Kurz C.
        • et al.
        First experimental-based characterization of oxygen ion beam depth dose distributions at the heidelberg ion-beam therapy center.
        Phys Med Biol. 2012; 57 (URL: 5017
        • Mairani A.
        • et al.
        Biologically optimized helium ion plans: calculation approach and its in vitro validation.
        Phys Med Biol. 2016; 61 (URL: 4283
        • Mairani A.
        • et al.
        Data-driven RBE parameterization for helium ion beams.
        Phys Med Biol. 2016; 61 (URL: 888
        • Marafini M.
        • et al.
        Secondary radiation measurements for particle therapy applications: nuclear fragmentation produced by 4He ion beams in a PMMA target.
        Phys Med Biol. 2017; 62 (URL: 1291
        • Matsufuji N.
        • et al.
        Spatial fragment distribution from a therapeutic pencil-like carbon beam in water.
        Phys Med Biol. 2005; 50 (URL: 3393
        • Mattei I.
        • et al.
        Addendum: measurement of charged particle yields from PMMA irradiated by a 220 MeV/u 12C beam.
        Phys Med Biol. 2017; 62 (URL: 8483
        • Mattei I.
        • et al.
        Secondary radiation measurements for particle therapy applications: prompt photons produced by 4He, 12C and 16O ion beams in a PMMA target.
        Phys Med Biol. 2017; 62 (URL: 1438
        • Muraro S.
        • et al.
        Monitoring of hadrontherapy treatments by means of charged particle detection.
        Front Oncol. 2016; 6 (URL: 177
        • Parodi K.
        Vision 20/20: positron emission tomography in radiation therapy planning, delivery, and monitoring.
        Med Phys. 2015; 42: 7153
        • Parodi K.
        • Bortfeld T.
        • Haberer T.
        Comparison between in-beam and offline positron emission tomography imaging of proton and carbon ion therapeutic irradiation at synchrotron- and cyclotron-based facilities.
        Int J Radiat Oncol Biol Phys. 2008; 71: 945-956
        • Parodi K.
        • Enghardt W.
        Potential application of PET in quality assurance of proton therapy.
        Phys Med Biol. 2000; 45 (URL: N151
        • Pennazio F.
        • et al.
        Carbon ions beam therapy monitoring with the inside in-beam pet.
        Phys Med Biol. 2018; (URL:
        • Piersanti L.
        • et al.
        Measurement of charged particle yields from PMMA irradiated by a 220 MeV/u 12 C beam.
        Phys Med Biol. 2014; 59 (URL: 1857
        • Reinhart A.
        • et al.
        Three dimensional reconstruction of therapeutic carbon ion beams in phantoms using single secondary ion tracks.
        Phys Med Biol. 2017; 62: 4884-4896
        • Richter C.
        • et al.
        First clinical application of a prompt gamma based in vivo proton range verification system.
        Radiother Oncol. 2016; 118 (URL: 232-237
        • Rucinski A.
        • et al.
        Secondary radiation measurements for particle therapy applications: charged particles produced by 4 he and 12 c ion beams in a pmma target at large angle.
        Phys Med Biol. 2018; 63 (URL: 055018
        • Salvador S.
        • Colin J.
        • Cussol D.
        • Divay C.
        • Fontbonne J.M.
        • Labalme M.
        Cross section measurements for production of positron emitters for pet imaging in carbon therapy.
        Phys Rev C. 2017; 95 (URL:
        • Seravalli E.
        • Robert C.
        • Bauer J.
        • Stichelbaut F.
        • Kurz C.
        • Smeets J.
        • Ty C.V.N.
        • Schaart D.R.
        • Buvat I.
        • Parodi K.
        • Verhaegen F.
        Monte carlo calculations of positron emitter yields in proton radiotherapy.
        Phys Med Biol. 2012; 57: 1659-1673
        • Sokol O.
        • et al.
        Oxygen beams for therapy: advanced biological treatment planning and experimental verification.
        Phys Med Biol. 2017; 62 (URL: 7798
        • Sportelli G.
        • et al.
        First full-beam PET acquisitions in proton therapy with a modular dual-head dedicated system.
        Phys Med Biol. 2014; 59 (URL: 43
        • Tommasino F.
        • Durante M.
        Proton Radiobiol Cancers (Basel). 2015; 7: 353-381
        • Tommasino F.
        • Scifoni E.
        • Durante M.
        New ions for therapy.
        Int J Particle Ther. 2015; 2: 428-438
        • Traini G.
        • et al.
        Design of a new tracking device for on-line beam range monitor in carbon therapy.
        Physica Med. 2017; 34: 18-27
        • Verburg J.
        • et al.
        Su-f-601-2: clinical translation of prompt gamma-ray spectroscopy for in vivo proton range verification.
        Med Phys (Scientific Abstracts and Sessions). 2017; 44: 2721-3318
        • Xie Y.
        • et al.
        Prompt gamma imaging for in vivo range verification of pencil beam scanning proton therapy.
        Int J Radiat Oncol Biol Phys. 2017; 99: 210-218