Neutron multiplicity from primary hot fragments produced in heavy ion reactions near Fermi energy

In order to reconstruct the yields of the primary hot fragments at the time of their formation, the neutron multiplicity associated with intermediate mass fragments (IMFs) was determined experimentally using the kinematical focusing of light particles emitted along the direction of each IMF. The reaction system 64Zn + 112Sn has been studied at 40 A MeV. IMFs were isotopically identified with Z up to 18. Neutrons were measured at 16 angles around the direction of the IMFs. The exctrated neutron multiplicities are in good agreement with those calculated AMD+Gemini simulations.