Particle response function in samarium and europium isotopes

The reaction (α,t) and (α,3He) have been performed with 100-MeV α-particles on targets of /sup 144,148,152,154/Sm to investigate high lying proton strength distribution in /sup 145,149,153,155/Eu and neutron strength distribution in /145,149,153,155/Sm, respectively. The emitted particles were identified in the S-320 spectrograph using two ΔE gas counters and an E plastic scintillator. Some differences were observed in the spectra depending on the nuclear deformation. Strong transitions to high-lying proton and neutron states up to about 15 MeV excitation energy were observed. Angular distributions were measured from 20 to 250 for both (α,t) and (α,3He) reactions. The extreme forward angle data points were necessary to determine the l-transfers. A smooth background, calculated using the α-breakup model, was subtracted from the spectra for excitation energies above 3 MeV. The background-subtracted spectra were divided into 520-keV wide bins and the angular distribution for each bin was fitted with DWBA calculations to obtain a strength distribution for each l-value