Possibility of estimation of the formation time of fragments in bombardment of nuclei by particles and nuclei of intermediate energies

It is shown that in bombardment of nuclei by fast particles and nuclei there is a preservation of the shape of the mass distributions of the fragment yields: of the isotopes of a single element. On the basis of this fact and the similarity of the shape of the spectra of light fragments, an attempt is made to estimate the time interval in which the fragments are formed