Present Status of Highly Charged Ion Experiments with an ECR Ion Source at TMU

Abstract

A highly charged ion facility built around a 14.25 GHz electron cyclotron resonance ion source has been constructed for the experimental investigation of low energy atomic collisions in Tokyo Metropolitan University. Four kinds of different experiments, namely differential scattering of electrons from ions, polarization spectroscopy for charge transfer reactions, Coulomb‐explosion‐imaging of molecular ions, and secondary ion measurements from solid surfaces, are taking place in parallel in this facility. General features of the facility and some recent results are described in this paper.

Dissociation of methanol dications produced by electron capture with and without transfer ionization

“…The experimental setup was the same as that reported previously [12], except for the scattered-beam analyser schematically shown in figure 1. The 120 keV Ar 8+ beam extracted from an electron-cyclotron-resonance ion source (TMU-ECRIS, [13]) crossed a molecular beam of methanol without seeding gas. The extraction field of 4.9 V mm −1 was used to direct recoil ions onto a position-sensitive detector (PSD 1 ).…”

4d-4f unresolved transition arrays of xenon and tin ions in charge exchange collisions

“…Multiply charged ions were produced in a 14.25 GHz ECR (electron cyclotron resonance) ion source at Tokyo Metropolitan University [20]. Xe gas was introduced in a plasma chamber for making Xe ions, and O 2 gas was added as a mixing gas to improve the ion intensities of higher charge states.…”

EUV emission spectra in collisions of multiply charged Sn ions with He and Xe

“…Spectroscopic data of Sn ions for individual charge states are necessary to diagnose and understand Sn plasmas. In previous work, we measured EUV emission spectra in collisions of Sn q+ (where q was in the range [6][7][8][9][10][11][12][13][14][15] with He by means of charge-exchange spectroscopy (CXS), and found that emissions from Sn VIII and Sn XI-XV contribute to the EUV emission from Sn plasmas at around 13.5 nm [10]. CXS has been used primarily for cross-section measurements of charge transfer processes.…”