title: Sensitivity of alanine dosimeters with gadolinium exposed to 6 MV photons at clinical doses.
abstract: In this study we analyzed the ESR signal of alanine dosimeters with gadolinium exposed to 6 MV linear accelerator photons. We observed that the addition of gadolinium brings about an improvement in the sensitivity to photons because of its high atomic number. The experimental data indicated that the addition of gadolinium increases the sensitivity of the alanine to 6 MV photons. This enhancement was better observed at high gadolinium concentrations for which the tissue equivalence is heavily reduced. However, information about the irradiation setup and of the radiation beam features allows one to correct for this difference. Monte Carlo simulations were carried out to obtain information on the expected effect of the addition of gadolinium on the dose absorbed by the alanine molecules inside the pellets. These results are compared with the experimental values, and the agreement is discussed.
authors.affiliation: Dipartimento di Fisica, Università di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo, Italy. maurizio.marrale@unipa.it
authors.forename: M
authors.initials: M
authors.lastname: Marrale
authors.forename: A
authors.initials: A
authors.lastname: Longo
authors.forename: M
authors.initials: M
authors.lastname: Spanò
authors.forename: A
authors.initials: A
authors.lastname: Bartolotta
authors.forename: M C
authors.initials: MC
authors.lastname: D'Oca
authors.forename: M
authors.initials: M
authors.lastname: Brai
mesh_terms: D000054:Acceleration; D000409:Alanine / Q000737:chemistry*; D004307:Dose-Response Relationship, Radiation; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D005682:Gadolinium / Q000737:chemistry*; D016014:Linear Models; D009010:Monte Carlo Method; D017785:Photons; D011874:Radiometry / Q000379:methods*; D014965:X-Rays
chemical_list: D005682:Gadolinium; D000409:Alanine