Radial dose distribution for 18.3 MeV/n alpha beams in tissue-equivalent gas.
Experimental measurements of the radial restricted linear energy transfer (LETr) for alpha beams of 18.3 MeV/n in tissue-equivalent gas were presented. The radial dose distribution for the alpha beam was deduced from the restricted LET measurements. A differential W value for the alpha particle in the tissue-equivalent gas was also deduced. The result for the differential W value was 29.0 +/- 0.9 eV/ion pair. The radial dose varied according to an inverse-square function with distance from the track center for radii larger than 0.026 micron. The maximum extension of the track, the penumbra radius, as 2.73 +/- 1.67 microns, which was less than predicted by calculations (7-9 microns).
Division of Physics, National Institute of Radiological Sciences, Chiba, Japan.
T
T
Kanai
K
K
Kawachi
D000512:Alpha Particles; D004735:Energy Transfer; D005740:Gases; D011829:Radiation Dosage
D005740:Gases