Chromatid-type aberrations following irradiation in G0 lymphocytes with heavy ions

We describe a low level of chromatid-type aberrations which included the relatively rare isochromatid/chromatid triradial in peripheral blood lymphocytes that were irradiated, ostensibly in G0, with accelerated heavy 12C ions. These were produced only at the energies of 69 MeV/n (34.6 keV/μm), almost absent at the energy of either 58.6 MeV/n (46.07 keV/μm) or 19.3 MeV/n (97 keV/μm), nor were they found after low-LET X-rays. Mechanisms potentially responsible for their formation are discussed.