The relative biological effectiveness of the modulated proton beam at TRIUMF.
OBJECTIVE
The purpose of this study was to determine the relative biological effectiveness (RBE) of proton beam and to study its dependency on fraction number.


METHODS
The relative biological effectiveness (RBE) of fractionated protons compared with 60Co gamma-rays was investigated for the acute mouse skin reaction. The 80 MeV protons generated at the TRIUMF cyclotron were spread out from 7 to 25 mm to irradiate entire legs. One, two, four, and eight fractions were tested.


RESULTS
RBE values ranged from 1.15 to 1.24 for the acute skin reaction. Fraction dose dependence of RBEs was not observed.
Nemoto
K
K
Department of Radiology, Tohoku University School of Medicine, Sendai, Japan.
Pickles
T
T
Minchinton
A I
AI
Lam
G K
GK
D000818:Animals; D003037:Cobalt Radioisotopes; D004307:Dose-Response Relationship, Radiation; D005260:Female; D051379:Mice; D008807:Mice, Inbred BALB C; D011522:Protons; D011882:Radiotherapy, High-Energy; D012062:Relative Biological Effectiveness; D012867:Skin / Q000528:radiation effects*
D003037:Cobalt Radioisotopes; D011522:Protons