Multichannel dosemeter and Al2O3:C optically stimulated luminescence fibre sensors for use in radiation therapy: evaluation with electron beams

Sylvain Magne (1) , Laureline Auger (1) , jean-marc bordy (2) , Loïc de Carlan (2) , A. Isambert (3) , A. Bridier (3) , Pierre Ferdinand (1) , Jean Barthe (2)

1 LCFO (CEA, LIST) - Laboratoire Capteurs Fibres Optiques (CEA, LIST)
2 LNHB (CEA, LIST) - Laboratoire National Henri Becquerel (CEA, LIST)
3 IGR - Institut Gustave Roussy

This article proposes an innovative multichannel optically stimulated luminescence (OSL) dosemeter for on-line in vivo dose verification in radiation therapy. OSL fibre sensors incorporating small Al2 O3 :C fibre crystals (TLD500 ) have been tested with an X-ray generator. A reproducible readout procedure should reduce the fading-induced uncertainty (~ 1% per decade). OSL readouts are temperature-dependent [~0.3% K^-1 when OSL stimulation is performed at the same temperature as irradiation; ~ 0.16% K^-1 after thermalisation (20°C)]. Sensor calibration and depth–dose measurements with electron beams have been performed with a Saturne 43 linear accelerator in reference conditions at CEA-LNHB (ionising radiation reference laboratory in France). Predosed OSL sensors show a good repeatability in multichannel operation and independence versus electron energy in the range (9, 18 MeV). The difference between absorbed doses measured by OSL and an ionisation chamber were within pm 0.9% (for a dose of about 1 Gy) despite a sublinear calibration curve.

Keywords: OSL fibre sensor; instrumentation; Optical Fiber Sensor; temperature; thermalisation; Sensor; calibration; calibration curve; Saturne 43 linear accelerator; Distributed and Quasi-distributed sensing; repeatability; radiation therapy; multichannel operation; X-rays; radiotherapy; dose verification; dosimetry; dose measurement; optically stimulated luminescence dosemeter; ionizing radiation; absorbed dose

Domains: Instrumentation and Detectors [physics.ins-det]; Optics / Photonic; Nuclear Experiment [nucl-ex]; Medical Physics [physics.med-ph]

Sylvain Magne, Laureline Auger, jean-marc bordy, Loïc de Carlan, A. Isambert, et al.. Multichannel dosemeter and Al2O3:C optically stimulated luminescence fibre sensors for use in radiation therapy: evaluation with electron beams. Radiation Protection Dosimetry, 2008, 131 (1), pp.93 - 99. ⟨10.1093/rpd/ncn226⟩. ⟨cea-01840716⟩