We have considered the accessibility condition of electromagnetic and electrostatic waves propagating in an electron cyclotron resonance (ECR) ion source (ECRIS) plasma and then investigated experimentally their correspondence relationships with production of multicharged ions. It has been clarified that there exists an efficient configuration of ECR zones for producing multicharged ion beams and has been suggested that a new resonance, i.e., upper hybrid resonance (UHR), must have occurred. We have been trying to perform advanced experiments with 4–6 GHz X-mode microwaves to the 2.45 GHz ECRIS plasma, and we have succeeded in enhancing the production of multicharged ions by launching X-mode microwaves of these bands. Furthermore, at the same time, we have observed sharp increases in electron energy distribution functions in the ECRIS plasma by means of probe methods. It has been concluded that the UHRs must have occurred when applying multiplex microwaves with their frequencies away from those frequencies for ECR in the ECRIS. In this paper, we will describe in brief the theoretical background and the results of these new experiments.

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Electron cyclotron resonance ion sources (ECRISs) are widely applied for ion beam applications, e.g., plasma processing, cancer therapy, and ion engine of an artificial satellite. In our ECRIS, we aim at producing and extracting various ion beams from this device, in particular, Xeq+ ion beams at low energy. In the aerospace engineering field, there are problems of accumulated damages on various component materials caused by low energy of Xe ions from the engine. There are not enough experimental sputtering data for satellite materials at the Xeq+ in the low energy region. Then, we are trying to investigate the sputtering yield experimentally by irradiating the low energy Xe ion beams. To perform this experiment, it is necessary to acquire a certain amount of beam current with low energy. Then, we generate the low energy ion beams by the following steps: First, the ion beams are extracted from the ECRIS at high voltage. Next, these are transported to an ion beam irradiation system (IBIS). Finally, the ion beams are decelerated by the deceleration voltage in the IBIS. We adjusted the beamline. We measure the characteristics of the transport efficiency and decelerated ion beam currents. In this paper, we describe the experimental setup using an existing ECRIS for decelerated heavy ion beams and the results of decelerated ion beam currents.

(a), T. TAGUCHI (a), and S. FUJITA (b) Oxygen in ZnTe is recognized as one of the isoelectronic impurities capable of forming a bound-exciton state. As ZnTe has been subjected to the incorporation /1, 2/, o r contamination /3/ by oxygen impurities during its preparation, a characteristic emission band is often observed at about 1.9 eV at 4.2 K (as shown in the insert to Fig. 1) which is the so-called oxygen-bound-exciton (OBE) luminescence, having associated with it many LO-and TA-phonon side-bands. 2It is our objective in this paper to show the effect of electron irradiation on the doublet spectra in the OBE luminescence, in which one can expect to introduce particular types of strain field due to the radiation-induced defects, in particular the Zn vacancy. We have found an annealing stage centred at about 100 O C for the recovery of the doublet intensities in the OBE luminescence, suggesting the possibility of long-range migration of Zn vacancy.1) Suita, Osaka 565, Japan.2 ) Yoshida, Kyoto 616, Japan.