インパルス加速型質量分析装置

抄録

If the accelerating voltage in a ion source is cut off before any of the ions leave the accelerating field, all the ions with same charge receive the same momentum. As the energy spectrum of such ions is the mass spectrum, is possible to devise a new mass spectrometer of impulsive type. A mass spectrometer based on such a principle was constructed. The pulse length of accelerating voltage was several hundreds millimicroseconds and the repetition rate was 5, 000 pulses per second. The accelerating field strength was about 70 volts per centimeter. The ionization electrons were put into the ionization chamber during the accelerating impulses were turned off. Two types of energy selector were used to get the mass spectrum of ions, the one consisted of radial electric field and the other retarding electric field. In this preliminary experiment, argon and nitrogen peaks could be resolved, and the resolving power was estimated to be about three.