The use of radioactive nuclear beams to study the equilibration of the $\text{N}\text{Z}$ degree of freedom in intermediate-energy heavy-ion reactions

Abstract

The effect of the neutron to proton ratio of the colliding system on the isotope ratio of the emitted fragments (1 ⩽ Z ⩽ 5) was studied for for a variety of constant mass beam-target combinations. To extend the $\text{N}\text{Z}$ ratio as far as possible, one of the projectiles employed, ⁴⁰Cl, was a radioactive secondary beam. The isotopic ratios depend on the $\text{N}\text{Z}$ of the target and beam in a way which is not consistent with $\text{N}\text{Z}$> equilibration on the timescale of the emission of intermediate-mass fragments.