Abstract
The effect of proton irradiation of biological cells, on timescales orders of magnitude shorter than with conventional accelerators, has been investigated by employing the TARANIS laser at Queen's University. Multiple cell-spots with different doses and proton energies were irradiated at the same time in a single laser shot at dose rates exceeding 109 Gy/sec. The data show a clear dose-dependant lethal effect of laser-driven protons over V-79 cells. A comparison with the survival obtained with an X-Ray standard source has been done and the resulting relative biological effectiveness (RBE) is about 1.3 at 10%.