Abstract
X-ray microbeam irradiation system has been installed in Central Research Institute of Electric Power Industry (Tokyo, Japan) to elucidate biological effects of low dose and low dose-rate radiation including X-ray-induced bystander response. It has already been reported many results about cellular response to charged particle (i.e., alpha particle) microbeams. On the other hand, it has not yet fully recognized that to X-rays, though it has been speculated that the biological responses are different from high-LET charged particles.
Our microbeam X-ray irradiation system was characterized by (1) desktop type (2) X-ray focusing system using Fresnel zone plate (FZP), and (3) on-line confocal laser microscope. Characteristic X-ray of aluminum (1.49 keV) was generated by focused electron bombardment of aluminum target. The bremsstrahlung radiation is removed by reflecting the radiation off an X-ray mirror. The FZP was used to focus aluminum K-shell X-ray. The size of X-ray beam is 2-3 μm in diameter detected by a scintillator. Confocal laser scanning microscope (FV300, Olympus) was equipped to obtain high resolution images from just irradiation. The details of the performance of our system and our visions will be present.
