Alanine films for EPR dosimetry of low-energy (1-30 keV) X-ray photons

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:459

Article

D'Oca, M. C.^1,2  Marrale, M.^1,2,3  Abbene, L.¹  Bartolotta, A.^1,2  Collura, G.^1,2  D'Errico, F.^4,5  Principato, F.¹ 

[1] Univ Palermo, Dept Phys & Chem, Viale Sci,Edificio 18, I-90128 Palermo, Italy

[2] Ist Nazl Fis Nucl, Via Santa Sofia 64, I-95123 Catania, Italy

[3] Univ Palermo, ATEN Ctr, Viale Sci,Edificio 18, I-90128 Palermo, Italy

[4] Univ Pisa, Sch Engn, Largo Lazzarino 1, I-56126 Pisa, Italy

[5] Yale Univ, Sch Med, 333 Cedar St, New Haven, CT 06520 USA

关键词: Electron paramagnetic resonance;    Low energy photons;    Alanine;   

DOI  :  10.1016/j.nimb.2019.08.011

来源: Elsevier

【 摘 要 】

L-alpha-alanine has aroused considerable interest for use in radiation EPR dosimetry and has been formally accepted as a secondary standard for high-dose (kGy) and transfer dosimetry of high-energy photons and electrons. In this work, we extended the investigation of the energy response of alanine EPR films in the low energy range for X-photons (1-30 keV). Electron Paramagnetic Resonance (EPR) measurements were performed on Kodak BioMax alanine films exposed to low-energy X-rays from a Cu-, W- and Mo-targets tube operating at voltages up to 30 kV. Films were chosen because of the low penetration of the soft X-rays used. The response of alanine to low-energy X-rays was characterized experimentally and the relative response (with respect to high energy photons) was found to be between 0.8 and 0.9 for Cu- and W-tube X-rays, and 1.0 for Mo-tube X-rays. The attenuation profiles were investigated and it was found that 1 mm of film material reduces the intensity of the X-ray-beam by about 70%, 50% and 40% for Cu-, W- and Mo-tube X-rays, respectively. Monte Carlo simulations were performed to model the energy release as well as the depth dose profiles for the various radiation beams used. These data are considered relevant for dosimetric applications in low energy beams such the high-gradient treatment fields used in monoenergetic microbeam radiation therapy (MRT) with synchrotron radiation as well as in brachytherapy with low energy sources, for instance Yb-169.

【 授权许可】

Free