Luminescence and characteristics of electron-holeplasma created in wide-band-gap crystals by ion irradiation.

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We are interested in high-density excitation by heavy ions, which is the highest exclitation in the present methods. In case of excitation of insulators with wide band-gaps, the intensity of excitation density by heavy ibns is three ofders higher thap tera W laser. In order to search phenomena characteristic to ion irradiation and elucidate dynamics of ion-tracks at initial stages. we developed a single ion and single photon (SISP) coincidence techaiques. At present, the time resolution is about, 85 ps, which is the fastest tool and is. better at least by order than usual techniques for ions. By application of SISP, we found ultra-fast luminescence commonly for many insulator crystals. Such lumjnescence has been not oberved and cannot be explained by so-far understanding. We proposed electron-hole plasma as origin of the fast luminescence with showimg evidences : non-tailed fast decay, super-linear excitation-density dependence of yield, sampl e dependence of yield, and little influence of temperaturle. However, there must be yet many unknown chaiacteristics regaiding with. e-h plasma in insulators, considering that e-h plasma in insulators is the frst finding and at starting point. Ih addition, so far our tirne-resolved spectra were apt to be influenced by beam fluctuation In order to overcome this week point and obtain precise spectra, we planed to construct simultaneous 8-wavelengths SISP and nbw this system is ready to measurements. However, the ion accelerator is in reconstruction since the last April. We are waiting the operation ofthe accelerator.