Study of the process by which the ions below 100 keV slow down

An attempt has been made to study the process by which the ions below 100 keV energy slow down, using the Alpha Recoil Doppler Shift Attenuation method. By using a long lived state such as the first excited state in 237Np(tsub(1/2)=60 ns) the doppler shift or ion velocity has been measured as a function of the length of time which the ion has recoiled. The energy loss -dE/dx(E) has been deduced, after computation and fitting of the data, the energy loss of the ion is found to be proportional to v rather than vsup(2/3) as suggested by some workers. (author)