Figure 6

Survival curves of logarithmically growing M059K and M059J cells asmeasured by colony formation after exposure to 1 GeV⁵⁸Fe ions (red symbols). Shown(gray symbols) for comparison are also results of experiments previouslyreported [24] with these cells after exposure to X-rays in the presence orabsence of 20 μM wortmannin. The figure also shows RBE valuescalculated at the indicated levels of cell survival. The lines drawnfollow the early data points [24] and are given as basis for comparisons with the resultsgenerated with ⁵⁸Fe.