CAJ | 학술논문

A compact pulse radiolysis apparatus using a BNL-type s-band photocathode RF gun is now under development at Waseda University. The laser pulse is used for excitation of the photocathode and for generation of white light, which is used for analyzing light in the pulse radiolysis.The system design is shown in Fig. 1. For absorption spectroscopy with wide wavelength region, the white-light continuum was used as analyzing light. The white light continuum was generated by focusing the high intense IR laser into the water cell. The available wavelength was 400-950 nm. Typical data obtained is shown in Fig.2 by using the system. We have performed a deconvolution technique to know the time resolution of our system. For this purpose, we have assumed the shapes of the electron pulse and the laser pulse as Gaussian distributions. Furthermore, the difference of velocity in a sample cell between the electron pulse and the laser pulse due to the refractive index of a sample was also taken into consideration and assuming that the hydrated electrons are formed as a step function and the response function is Gaussian.Thus, time resolution of the system was estimated by deconvolution of the experimental data.We have achieved a time resolution of about 26ps by measuring time profile of hydrated electrons in H2O.