超伝導電磁石を用いたフーリエ変換イオンサイクロトロン共鳴質量分析計の試作. I.

抄録

This paper reports a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer built in this laboratory. The spectrometer consists of a 5 Tesla superconducting magnet, a cylindrical trapped ion cell with an electron beam source, electronic circuits, a microcomputer which generates pulse sequence and controls a data acquisitions system, and a personal computer.
The mass spectrum of xenon isotopes has been obtained by a preliminary experiment. An intense low frequency signal of several hundreds Hz was observed along with the time domain transient signals of ion cyclotron resonance frequencies. The former can be attributed to the rotation of the center of cyclotron motion of ions about the cell axis. This rotational motion is caused by the drift due to the radial electric field component and the magnetic field gradient produced in the plane perpendicular to the cell axis.
Analysis of the inhomogeneities of electric and magnetic fields inside the cell and the motion of ions has been carried out and the variation of the frequency of rotation as a function of the kinetic energy of ions has been studied.