Alpha energy distribution as a probe for the feeding of ND and SD bands in Dy-151,Dy-152 nuclei

The study of the alpha-particle energy distributions associated with ND and SD states in Dy-151,Dy-152 has been carried out. The Dy isotopes were produced in the reaction Cl-37+Sb-123 at 191 MeV via the (alpha 5n) and (alpha 4n) channels, respectively. In Dy-151 the alpha-particle energy distributions associated to ND and SD are very different from each other, both at the low and high energy sides inducing a difference of 3 MeV in the alpha-particle mean energy. In Dy-152 the situation is different; the alpha-particle spectral shapes are similar and a difference in the alpha-particle mean energy of only 0.7 MeV is deduced. A description in terms of energy localization of entry states is given.