title: Dosimetric characterization of a synthetic single crystal diamond detector in clinical radiation therapy small photon beams.
abstract: OBJECTIVE
  To determine the potentialities of synthetic single crystal diamond Schottky diodes for accurate dose measurements in radiation therapy small photon beams.
  
  
  METHODS
  The dosimetric properties of a diamond-based detector were assessed by comparison with a reference microionization chamber. The diamond device was operated at zero bias voltage under irradiation with high-energy radiotherapic photon beams. The stability of the detector response and its dose and dose rate dependence were measured. Different square field sizes ranging from 1 × 1 cm(2) to 10 × 10 cm(2) were used during comparative dose distribution measurements by means of percentage depth dose curves (PDDs), lateral beam profiles, and output factors. The angular and temperature dependence of the diamond detector response were also studied.
  
  
  RESULTS
  The detector response shows a deviation from linearity of less than ±0.5% in the 0.01-7 Gy range and dose rate dependence below ±0.5% in the 1-6 Gy∕min range. PDDs and output factors are in good agreement with those measured by the reference ionization chamber within 1%. No angular dependence is observed by rotating the detector along its axis, while ∼3.5% maximum difference is measured by varying the radiation incidence angle in the polar direction. The temperature dependence was investigated as well and a ±0.2% variation of the detector response is found in the 18-40 °C range.
  
  
  CONCLUSIONS
  The obtained results indicate the investigated synthetic diamond-based detector as a candidate for small field clinical radiation dosimetry in advanced radiation therapy techniques.
authors: Dipartimento di Ingegneria Industriale, Università di Roma Tor Vergata,Via del Politecnico 1, Roma, Italy.
authors: I
authors: I
authors: Ciancaglioni
authors: Marco
authors: M
authors: Marinelli
authors: E
authors: E
authors: Milani
authors: G
authors: G
authors: Prestopino
authors: C
authors: C
authors: Verona
authors: G
authors: G
authors: Verona-Rinati
authors: R
authors: R
authors: Consorti
authors: A
authors: A
authors: Petrucci
authors: F
authors: F
authors: De Notaristefani
mesh_terms: D003460:Crystallization; D018130:Diamond / Q000737:chemistry* / Q000528:radiation effects*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D017785:Photons / Q000627:therapeutic use; D011829:Radiation Dosage; D011874:Radiometry / Q000295:instrumentation* / Q000379:methods
chemical_list: D018130:Diamond