for 8.78 MeV Alpha Particles

The stopping powers of Al, Ni, Cu, Ag, andTa have been measured by using the absorber wheel technique and a silicon detector. In order to examine the possible nonuniformity of the sample foil, the alpha particle beam was made scan in two directions, i.e. parallel and perpendicular to the rolling direction of the foil. The agreement between the measurements of two directions was proved to be satisfactory. The present results were devided by 4 and reduced to 2.0 MeV and compared with the proton data from the table of Bichsel. It turned out that the data for alpha particles are by 3.4 percent higher than those for protons. I