title: Reference dosimetry for light-ion beams based on graphite calorimetry.
abstract: Developments in hadron therapy require efforts to improve the accuracy of the dose delivered to a target volume. Here, the determination of the absorbed dose under reference conditions was analysed. Based on the International Atomic Energy Agency TRS-398 code of practice, for hadron beams, the combined standard uncertainty on absorbed dose to water under reference conditions, derived from ionisation chambers, is too large. This uncertainty is dominated by the beam quality correction factors, [Formula: see text], mainly due to the mean energy to produce one ion pair in air, wair. A method to reduce this uncertainty is to carry out primary dosimetry, using calorimetry. A [Formula: see text]-value can be derived from a direct comparison between calorimetry and ionometry. Here, this comparison is performed using a graphite calorimeter in an 80-MeV A(-1) carbon ion beam. Assuming recommended TRS-398 values of water-to-graphite stopping power ratio and the perturbation factor for an ionisation chamber, preliminary results indicate a wair-value of 35.5 ± 0.9 J C(-1).
authors: Center of Molecular Imaging, Radiotherapy and Oncology, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium severine.rossomme@uclouvain.be.
authors: S
authors: S
authors: Rossomme
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: H
authors: H
authors: Palmans
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: R
authors: R
authors: Thomas
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: N
authors: N
authors: Lee
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: S
authors: S
authors: Duane
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: M
authors: M
authors: Bailey
authors: National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington, UK.
authors: D
authors: D
authors: Shipley
authors: Ion Beam Applications s.a., Louvain-la-Neuve, Belgium.
authors: D
authors: D
authors: Bertrand
authors: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy.
authors: F
authors: F
authors: Romano
authors: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy.
authors: P
authors: P
authors: Cirrone
authors: Laboratori Nazionali del Sud, Istituto Nazionale di Fisica Nucleare, Catania, Italy.
authors: G
authors: G
authors: Cuttone
authors: Center of Molecular Imaging, Radiotherapy and Oncology, Institut de Recherche Expérimentale et Clinique, Université catholique de Louvain, Brussels, Belgium Radiotherapy and Oncology Department, Cliniques Universitaires Saint-Luc, Brussels, Belgium.
authors: S
authors: S
authors: Vynckier
mesh_terms: D000388:Air; D002138:Calibration; D002151:Calorimetry / Q000379:methods*; D002244:Carbon; D006108:Graphite / Q000737:chemistry*; D006358:Hot Temperature; D006801:Humans; D007477:Ions; D009010:Monte Carlo Method; D011874:Radiometry / Q000295:instrumentation / Q000379:methods*; D011879:Radiotherapy Dosage; D012016:Reference Values; D015203:Reproducibility of Results; D014867:Water / Q000737:chemistry
chemical_list: D007477:Ions; D014867:Water; D002244:Carbon; D006108:Graphite