8Li Fragments Associated with Nuclear Disintegration
Il Nuovo Cimento
Original Item ID
This paper is a preliminary report on the emission of heavy fragments in nuclear disintegration. It is assumed that the probability of emission of a heavy fragment depends on the nuclear temperature (T) and the potential barrier (V) of the excited nucleus. It is the purpose of this investigation to study the dependence of the differential energy spectrum on the excitation energy. The data collected were from four stacks of Ilford G-5 emulsions, exposed to (a) a stopped pion beam; (b) 400 MeV proton beam; (c) (4÷5) GeV pion beam and (d) cosmic rays with an exposure in Texas, Magnetic latitude of 41° N, and on the Island of Guam at the magnetic equator. In this report emphasis will be placed on the emission of 8Li as the heavy fragment. The results of the experiment indicate that for high excitation energy there is a collimation of lithium and beryllium fragments in the forward direction which may be explained on the basis of evaporation theory by assuming the fragment emission to take place during the flight of a highly excited nucleus. In the case of low excitation energy the angular distribution of 8Li fragments is isotropic and the energy distribution indicates that the majority result from the absorption of aπ−-meson by a light nucleus.