With the prototype ECR ion source for the next carbon therapy facility in Japan a new series of measurements has been performed in order(a)to find the highest beam currents of C^(4+) ions,and(b)to study the effect of&...With the prototype ECR ion source for the next carbon therapy facility in Japan a new series of measurements has been performed in order(a)to find the highest beam currents of C^(4+) ions,and(b)to study the effect of'special'gas-mixing by using a chemical compound as a feed gas.An isotopic effect has been found in a previous experiment:with deuterated methane(CD_4 gas) the C^(5+) beam currents are about 10% higher than with regular methane(CH_4 gas).For butane gases(C_4D_(10) and C_4H_(10) respectively)the isotopic effect for C^(5+) production is even stronger(>15%).For production of C^(4+) ions the isotopic effect appears to be absent.It turns out that the relative amount of carbon is much more important:acetylene gives 15% higher C^(4+) current than butane,which in turn gives about 10% higher C^(4+) ion currents than methane.展开更多
Four ECR ion sources have been operated in National Institute of Radiological Sciences(NIRS). Two ECR ion sources supply various ion species for the Heavy Ion Medical Accelerator in Chiba(HIMAC). The 10GHz NIRS-ECR io...Four ECR ion sources have been operated in National Institute of Radiological Sciences(NIRS). Two ECR ion sources supply various ion species for the Heavy Ion Medical Accelerator in Chiba(HIMAC). The 10GHz NIRS-ECR ion source mainly produces C^(2+) ions for the heavy-ion therapy.Ions of Si,Ar,Fe,Kr and Xe are usually produced by the 18GHz NIRS-HEC ion source for physical and biological experiments.The other two compact ECR ion sources with all permanent magnet configuration have been developed for the new generation carbon therapy facility.One of these,the Kei-source,is a prototype which has been installed to the NIRS-930 cyclotron for axial injection.The other source,Kei2-source,is a demonstration source and utilized for the new generation Linac.In addition,both Kei sources have been used to study fundamental properties. In this paper,present status of the ion sources and recent developments are reported.展开更多
文摘With the prototype ECR ion source for the next carbon therapy facility in Japan a new series of measurements has been performed in order(a)to find the highest beam currents of C^(4+) ions,and(b)to study the effect of'special'gas-mixing by using a chemical compound as a feed gas.An isotopic effect has been found in a previous experiment:with deuterated methane(CD_4 gas) the C^(5+) beam currents are about 10% higher than with regular methane(CH_4 gas).For butane gases(C_4D_(10) and C_4H_(10) respectively)the isotopic effect for C^(5+) production is even stronger(>15%).For production of C^(4+) ions the isotopic effect appears to be absent.It turns out that the relative amount of carbon is much more important:acetylene gives 15% higher C^(4+) current than butane,which in turn gives about 10% higher C^(4+) ion currents than methane.
文摘Four ECR ion sources have been operated in National Institute of Radiological Sciences(NIRS). Two ECR ion sources supply various ion species for the Heavy Ion Medical Accelerator in Chiba(HIMAC). The 10GHz NIRS-ECR ion source mainly produces C^(2+) ions for the heavy-ion therapy.Ions of Si,Ar,Fe,Kr and Xe are usually produced by the 18GHz NIRS-HEC ion source for physical and biological experiments.The other two compact ECR ion sources with all permanent magnet configuration have been developed for the new generation carbon therapy facility.One of these,the Kei-source,is a prototype which has been installed to the NIRS-930 cyclotron for axial injection.The other source,Kei2-source,is a demonstration source and utilized for the new generation Linac.In addition,both Kei sources have been used to study fundamental properties. In this paper,present status of the ion sources and recent developments are reported.
