Fusion cross-section and angular momentum in 19F + 165Ho

We have measured the fusion cross-section and the gamma-ray multiplicity in the 19F+165Ho system. The measurements were made using the 19Fe beam in the energy range 74-95 MeV at the Pelletron accelerator facility. Targets (≅250μg/cm2) were made by vacuum evaporation on rolled Al and Pb foils. Measurements for fusion cross-section and the gamma-ray multiplicity distribution were done independently. The measurement for determining the fusion cross-sections, was done using the 1-metre diameter scattering chamber with a special housing for a 125cm3 HpGe. Two surface barrier detectors placed symmetrically about the beam were used for absolute normalization. The total fusion cross-section was obtained from the sum of the cross-section for the 4n,5n,6n evaporation residue channels. This was obtained by measuring the yields of the characteristic gamma-rays of the evaporation residues (offline) with an efficiency calibrated HpGe. The gamma-ray fold distribution was measured using 2 sets of 7 closely packed hexagonal BGO detectors (3 inches x 2 inches) placed above and below a narrow vacuum chamber in coincidence with a HpGe placed in the horizontal plane. The BGO's covered ≅ 65% of the geometric solid angle. The data were unfolded for the detector response. The average multiplicity obtained was converted into angular momentum, (L) using an available prescription. (author). 6 refs., 1 fig