Quantitative study of ion beam production from solid surface irradiated with ultra-high peak power laser

Research and development to apply the laser-produced ion beam for cancer-therapy has recently been performed with collaboration among JAERI, Kansai, ICR, Kyoto University and NIRS. The first experimental study with use of 100TW, ∼20 fsec laser has been made and the following one is now under discussion. From the preparatory experiments using the several TW, ultra-short pulse (50∼130 fsec) laser, it is shown that ion production from thin foil is largely affected with the condition of the pre-pulse. While its high energy is a great advantage as an ion source, the number of ions decreases exponentially with its energy. So as to reduce the energy spread, phase rotation in the longitudinal phase space is planned with use of an RF electron field synchronized to the pulse-laser. (author)