Effect of deformation on prescission particle emission in the reaction of 10.6 MeV/u Kr-84+Al-27

Effect of deformation on prescission particle emission was studied. The fis sion delay time extracted from the measured prescission light charged parti cle multiplicity of fission of light system In-111, produced in 10.6MeV/u K r-84 + Al-27 collision, is reduced to 5 x 10(-21) s from 20 x 10(-21)s, if including deformation effect, which indicates that part of the excess of pr escission particle emission comes from the deformation effect contribution. The reason is that deformation of the system leads to a decrease of the ba rriers for proton and alpha particle emission even larger than the increase of their binding energies.