中文摘要：

We have measured the cross-section ratios of helium induced by C q+ and O q+ (q=1-4) in an energy range from 20 keV/amu to 500 keV/amu,and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system.Hence,we obtain the ratios of total single-ionization cross-sections (SI,SC,SLSI,and DLSI),total double-ionization cross-sections (DI,DC,TI,SLDI,and DLDI) and cross-sections of every process (SI,SC,SLSI,DLSI,DI,DC,TI,SLDI,and DLDI),which induce the single-ionization and double-ionization,to the total cross sections respectively.The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly,and the qualitative explanations involved in those results are also presented accordingly.

英文摘要：

We have measured the cross-section ratios of helium induced by Cq＋ and Oq＋ （q = 1-4） in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections （SI, SC, SLSI, and DLSI）, total double-ionization cross-sections （DI, DC, TI, SLDI, and DLDI） and cross-sections of every process （SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI）, which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly.