[1] UCM, Madrid, Spain
[2] Inst Invest Sanitaria San Carlos, Grp Fis Nucl, Madrid, Spain
[3] IPARCOS, Madrid, Spain
[4] UCM, Grp Fis Nucl, Madrid, Spain
[5] UAM, CMAM, Madrid, Spain
[6] Hosp Fuenlabrada, Dept Radiofis Protecc Radiol, Fuenlabrada, Spain
[7] Hosp Quironsalud, Ctr Protonterapia, Pozuelo, Spain