Isospin effects on light charged particles as probes of nuclear dissipation

The multiplicities of postsaddle protons and α particles of the heavy systems ²³⁴Cf, ²⁴⁰Cf, ²⁴⁶Cf, and ²⁴⁰U as functions of the postsaddle dissipation strength are calculated in the framework of a dynamical Langevin model coupled with a statistical decay model. It is found that with increasing isospin of the Cf system, the sensitivity of the postsaddle proton and α-particle multiplicity to the dissipation strength decreases substantially, and it disappears for the ²⁴⁰U system. We suggest that on the experimental side, to accurately probe the postsaddle dissipation strength by measuring the prescission proton and α-particle multiplicity, it is best to populate heavy compound systems with low isospin.