Deuteron-induced reactions on Y89 and nuclear level density of 90Zr

Experimental elastic scattering and double differential cross sections of ⁸⁹Y(d ,n) and ⁸⁹Y(d ,p) reactions have been measured with 5, 6, and 7.44 MeV deuteron beams. It was found that about 76% of the total reaction cross sections are determined by the compound mechanism and the rest is due to direct and preequilibrium interactions. Cross sections measured at backward angles were compared with calculations based on the compound nuclear Hauser-Feshbach model. It was found that it is possible to reproduce the backward angle neutron cross sections by the compound model, but it fails to describe proton cross sections. A pronounced peak is observed in neutron differential cross section which might result from strongly populated states 0⁺,4^-, and 5^- of ⁹⁰Zr via direct stripping reactions. The level density of ⁹⁰Zr has been obtained from neutron cross sections measured at backward angles. It is best described with the constant-temperature level density model versus the traditional Fermi-gas one.