title: Monte Carlo investigation of energy response of various detector materials in ¹²⁵I and ¹⁶⁹Yb brachytherapy dosimetry.
abstract: Relative absorbed-dose energy response correction R for different detector materials in water, PMMA and polystyrene phantoms are calculated using Monte Carlo-based EGSnrc code system for ¹²⁵I and ¹⁶⁹Yb brachytherapy sources. The values of R obtained for ¹²⁵I source are 1.41, 0.92, 3.97, 0.47, 8.32 and 1.10, respectively, for detector materials LiF, Li₂B₄O₇ , A1₂O₃, diamond, silicon diode and air. These values are insensitive to source-to-detector distance and phantom material. For ¹⁶⁹Yb source, R is sensitive to source-to-detector distance for detector materials other than air and Li₂B₄O₇. For silicon, R increases from 3 to 4.23 when depth in water is increased from 0.5 cm to 15 cm. For ¹⁶⁹Yb source, the values of R obtained for air and Li₂B₄O₇ in PMMA and polystyrene phantoms are comparable to that obtained in water. However, LiF, Si and A1₂O₃ show enhanced response and diamond shows decreased response in PMMA and polystyrene phantoms than in water.
authors.affiliation: Radiological Physics and Advisory Division, Health, Safety and Environment Group, Bhabha Atomic Research Centre, Mumbai, India. pselvam66@yahoo.co.in
authors.forename: T Palani
authors.initials: TP
authors.lastname: Selvam
authors.forename: Biju
authors.initials: B
authors.lastname: Keshavkumar
mesh_terms: D001918:Brachytherapy / Q000295:instrumentation*; D006801:Humans; D007457:Iodine Radioisotopes; D009010:Monte Carlo Method; D019047:Phantoms, Imaging; D011874:Radiometry / Q000295:instrumentation*; D011879:Radiotherapy Dosage; D014867:Water; D015018:Ytterbium
chemical_list: D007457:Iodine Radioisotopes; D014867:Water; D015018:Ytterbium