Characterization of passive dosimeters in proton pencil beam scanning – A EURADOS intercomparison for mailed dosimetry audits in proton therapy centres

Abstract The lack of mailed dosimetry audits proton therapy centres in Europe has encouraged researchers EURADOS Working Group 9 (WG9) to compare response several existing passive detector systems therapeutic pencil beam scanning. Alanine Electron Paramagnetic Resonance from 3 different institutes (ISS, Italy; UH, Belgium and IFJ PAN, Poland), natLiF:Mg, Ti (MTS-N) Cu, P (MCP-N) thermoluminescent dosimeters (TLDs), GD-352M radiophotoluminescent glass (RPLGDs) Al2O3:C optically stimulated (OSLDs) were evaluate. Dosimeter repeatability, batch reproducibility Pencil Beam Scanning verified for implementation as mail auditing system. detectors demonstrated the lowest linear energy transfer (LET) dependence with an agreement between measured treatment planning system (TPS) dose below 1%. OSLDs on average a 6.3% lower compared TPS calculation, no significant difference varying modulations ranges. Both MCP-N than luminescent was dependent LET beam. Thermoluminescent MTS-N also found be higher most pronounced increase 11%. As alanine are characterized by parameters scanning they suitable candidates therapy. luminescence have shown promises even though more careful calibration corrections needed its part audit