Experimental verification of therapeutic doses for the superficially-placed tumor radiotherapy with heavy ions at HIRFL

Up to now, clinical trials of heavy-ion radiotherapy for superficially placed tumors have been carried out for six times and over 60 selected patients have been treated with 80—100 MeV/u carbon ions supplied by the Heavy Ion Research Facility in Lanzhou (HIRFL) at the Institute of Modern Physics, Chinese Academy of Sciences since November, 2006. A passive irradiation system and a dose optimization method for radiotherapy with carbon-ion beams have been developed. Experimental verification of longitudinally ...

Design of the IMP microbeam irradiation system for 100 MeV/u heavy ions

Abstract A state-of-the-art high energy heavy ion microbeam irradiation system is constructed at the Institute of Modern Physics of the Chinese Academy of Sciences. This microbeam system operates in both full current intensity mode and single ion mode. It delivers a predefined number of ions to preselected targets for research in biology and material science. The characteristic of this microbeam system is high energy and vertical irradiation. A quadrupole focusing system, in combination with a series of slits, has been designed to optimize the spatial resolution. A symmetrically achromatic system leads the beam downwards and serves simultaneously as an energy analyzer. A high gradient quadrupole triplet finally focuses a C6+ ion beam to 1 µm in the vacuum chamber within the energy range from 10 MeV/u to 100 MeV/u. In this paper, the IMP microbeam system is described in detail. A systematic investigation of the ion beam optics of this microbeam system is presented together with the associated aberrations. Comparison is made between the IMP microbeam system and the other existing systems to further discuss the performance of this microbeam. Then the optimized initial beam parameters are given for high resolution and high hitting efficiency. At last, the experiment platform is briefly introduced.

Comparison doses of secondary neutron with the heavy ions in a 75-mev/n heavy ion beam

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Flower color chimera and abnormal leaf mutants induced by C-12(6+) heavy ions in Salvia splendens Ker-Gawl.

The effect of C-12(6+) heavy ions bombardment on mutagenesis in Salvia splendens Ker-Gawl. was studied. Dose-response studies indicated that there was a peak of malformation frequency of S. splendens at 200 Gy. Abnormal leaf mutants of the bileaf, trileaf and tetraleaf conglutination were selected. Meanwhile, a bicolor flower chimera with dark red and fresh red flower was isolated in M1 generation of S. splendens. Random amplified polymorphic DNA (RAPD) analysis demonstrated that DNA variations existed among the wild-type, fresh and dark red flower shoots of the chimera. The dark red flower shoots of the chimera were conserved and cultivated at a large-scale through micropropagation. MS supplemented with 2.0 mg/L BA and 0.3 mg/L NAA was the optimal medium in which the maximum proliferation ratio (5.2-fold) and rooting rate (88%) were achieved after 6 weeks. Our findings provide an important method to improve the ornamental quality of S. splendens.