title: [Effect of single alpha-particle on cells].
abstract: The mechanisms of biological effect of charged particles in space was studied through the inactivation effect of very low-density charged particles on very low-density cells at different impact parameters. A small type of microbeam facility with alpha-radioactive source and CN track detector were used. A diploid wild type Saccharomyces cerevisiae served as experimental eukaryotic cell. The correlation between cell inactivation and impact parameter of alpha-particles on cells was obtained through a CCD-camera system. The results showed that inactivation range of 1.13 MeV/u alpha-particles on cell-agarose mixture was about 5.5 micrometers, larger than the sum (about 3.l micrometers) of ion track-penumbra radius and yeast cell radius. The cell inactivation rate was 0.36-0.33. It suggests that multi-hit on a cell is necessary for killing it. However, in case of miss, the inactivation rate may not be zero at certain impact parameters.
authors.affiliation: Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Wei
authors.forename: H D
authors.initials: HD
authors.lastname: Pross
mesh_terms: D000512:Alpha Particles; D010315:Particle Accelerators; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000295:instrumentation; D011874:Radiometry; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000528:radiation effects*