Number and spectra of neutrons for fixed fragments on Cf252 spontaneous fission

Results are reported of experimental determination of number and spectra of prompt neutrons from spontaneous fission of 252Cf depending on the mass and total kinetic energy of the fragments. Information of the fragment masses is extracted from the data on measurement of their kinetic energy by means of the semi conductor detectors. A scintillation spectrometer of the recoil protons has been used to investigate the neutron spectra. The measurements are fulfilled for two values of the angle between the fragment separation axis and the neutron motion direction, 8.7 deg and 90 deg. The obtained data are compared with the results of other investigations and are discussed in framework of the existing picture of the neutron emission mechanism