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[en] The particle-γ coincidence technique has been applied for the study of reactions between ¹⁶¹Dy and ⁶¹Ni at center-of-mass energy of 195.8 MeV. The γrays were detected with the EUROGAM array which has 45 Compton-suppressed Ge detectors in coincidence with the detection of backscattered Ni-like particles in a position-sensitive PPAC. A total of 44 M double and 4.5 M triple γ rays were collected. Inelastic and one-neutron pickup and strippling channels dominate the discrete γ rays. Evidence of population of quasicontinuum region in the one-neutron pickup channel is observed. The apparent γ-ray energy correlations between Ni-like and Dy-like reaction products give the possibility to study the excitation-sharing between projectile-like and target-like particles. Some preliminary results will be presented

[en] High spin states of ¹⁶⁴Lu are populated using the ¹⁴⁹sm(¹⁹F, 4n)¹⁶⁴Lu reaction at a beam energy of 85 MeV. The experiment was carried out at the Nuclear Structure Research Lab the University of Rochester, and the beam was provided by the Rochester MP tandem accelerator. Gamma rays were detected by 8 Compton-suppressed Ge detectors, and about 16 million gamma-gamma coincidence events were accumulated. A preliminary analysis tentatively established 5 rotational bands in ¹⁶⁴Lu. The energy levels and other properties of the nucleus will be will be discussed and compared to its neighboring nuclei

[en] New half-life measurements have been made of the millisecond isomers "7"1"mGe, "1"1"4"m"2I, "2"0"8"mBi, "8"8"m"1Y, "8"8"m"2Y, and "7"5"mAs populated in neutron-induced reactions. These measurements were made using the unique time structure of the LANSCE/WNR neutron source, by observing the γ-ray decays of the isomers during the time between the LANSCE proton macropulses. Two different LANSCE proton beam time structures were used. The GEANIE array of HPGe detectors was used to detect the γ-ray decays

[en] A detector system has been developed to uniquely identify binary reaction channels and accurately measure Q-value distributions in order to study heavy-ion induced few-nucleon transfer reactions at sub-barrier energies. A 1.4m time-of-flight arm, comprising a microchannel plate timing detector followed by two segmented Si strip detectors, it is used to detect the backscattered projectile-like nuclei-in kinematic coincidence with the recoiling target-like nuclei detected by a PPAC in the focal plane of a split-pole magnetic spectrograph. The masses of both reaction products are determined from the time-of-flight, energy and magnetic rigidity measurements. Mass resolutions of better than 1 a.m.u. and Q-value resolutions of better than 800 keV are obtained in the system ⁵⁸Ni + ¹⁶²Dy. Recent measurements of the few-neutron transfer cross sections and Q-value distributions in the systems ⁵⁸Ni + ^161,162Dy at energies near and below the Coulomb barrier will be presented

[en] Six SD bands were populated in ¹⁴³Eu and ¹⁴⁴Eu, two of which had not been previously observed. Sum spectra were generated to search for two step links from the yrast SD band in ¹⁴³Eu. However, no two step links were found. A single link from the SD band in ¹⁴³Eu was found at 3364 keV. The level where it feeds into has not been identified. Alpha-particle energy (E_α) spectra leading to the SD band and to normal states in ¹⁴³Eu were measured and a correlation was found between E_α and the level spin of the residual nucleus

[en] The effects introduced by 4π charged-particle detector arrays such as the Microball on lifetime measurements by Doppler-shift attenuation techniques are discussed. The effect originates from the lower efficiency for detecting charged particles at backward angles. Procedures for correcting for such 'bias' are described

[en] The Microball, a compact, 4π charged-particle detector array, has been used in conjunction with Gammasphere for numerous physics experiments, and more are planned in the near future. A summary of this research program is presented, and the device and its capabilities are described. An example of its use in the study of the population and entry state excitation energy distributions of normal and superdeformed bands in ⁸²Sr is presented

[en] Nuclear data collected in an experiment performed at LANSCE/WNR with the GEANIE spectrometer to measure the cross sections for n + ⁸⁹Y for E_n < 20 MeV are reported. The estimated (n, 2n) cross sections to the ground and isomeric states of ⁸⁸Y differ significantly from those listed in the RADCHEM data base. Folded with a fast neutron spectrum, these results lead to integral differences of +15%, +2%, and -70% vs. the RADCHEM evaluation.

[en] Taking advantage of the neutron source of the LANCSE, it has been possible to obtain a measure of the velocity distribution and the number of prompt-neutrons emitted in the neutron-induced fission of ²³⁸U and ²³⁷Np over a broad incident neutron energy range. The mean kinetic energy was extracted and is shown as the function of the incident-neutron energy. We confirm here the observation, for both reactions, of a dip around the second chance fission which is explained by the lower kinetic energy of the pre-fission neutrons. Such a observation is reproduced by Los Alamos model as implemented at Bruyeres le Chatel and by the Maslov model. As far as the neutron multiplicity is concerned, a similar dip is observed. However, such a behavior is not present in data measured by other groups