MASS ENERGY ANALYZER FOR NEUTRAL PARTICLE

摘要

PURPOSE:To remove effect of a leakage electric field of an electrostatic deflection plate with the ion passage electrode length thereof sufficiently larger than an interval of the deflection plate, by providing an acceleration electrode between a displacement electromagnet and the electrostatic deflection plate to accelerate neutral particles ionized. CONSTITUTION:Neutral particles 6 made incident into a vacuum container 1 from a nuclear fuser not illustrated are ionized with charge exchange by a neutral gas in a stripping cell 2 and turned to ions (f). The incident ions (f) perform a rotary motion with the radius corresponding to energy by a Larmor's motion with a deflection electromagnet 3 to enable discrimination of momentum. An acceleration electrode 7 is provided between the electromagnet 3 and an electrostatic deflection plate 4a for discrimination of mass. This allows a larger electrode length (e) of the electrostatic deflection plate 4a to remove effect due to a leakage electric field at an end thereof 4a thereby achieving a mass spectrograph with limited errors even with respect to neutral particles with a low energy. Thus, the momentum and mass of the incident particles 6 are measured depending on which position the ions (f) reach on a particle detector 5.