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From multiparameter data obtained at Lawrence Berkeley National Laboratory, the integral characteristics of the prompt γ-ray emission were extracted for tripartition of ²⁵²Cf with He, Be and C being the third light charged particle. We used multifold γ-ray coincidence spectra for the determination of γ-ray multiplicities assuming a Gaussian distribution for γ-ray multiplicity. The multiplicity distribution characteristics, i.e. mean multiplicity and its dispersion were obtained by minimizing with respect to the calculated values of probabilities of multifold γ-ray coincidences using a combinatoric method. Comparison with the known experimental data from binary fission was made. Further, we investigated dependencies of the mean γ-ray multiplicity on the kinetic energy of the light charged particle. The mean γ-ray multiplicity for He ternary fission is found to increase rapidly with increasing kinetic energy of He in the region less than 11 MeV and then decrease slowly with increasing kinetic energy of He. The anomalous behaviour of γ-ray emission is discussed. The mean γ-ray multiplicity was determined for the first time for Be and C ternary fission. For Be, the γ-ray multiplicity as a function of kinetic energy was obtained as well.

High-spin states in the neutron-deficient isotope ¹⁰⁴Cd were populated using the ⁵⁰Cr(⁵⁸Ni,4p)¹⁰⁴Cd reaction at a beam energy of 250 MeV. The level scheme has been extended using triple γ-ray coincidences to a spin of 29ℏ and an excitation energy of 18.2 MeV. Several collective structures involving the excitation of h_11/2 neutrons have been observed to spins approaching 30ℏ. The high-spin structure has been compared to the results of cranked Nilsson–Strutinsky calculations.

New excited states built on the 11/2⁻ isomeric states are identified in neutron-rich ^121,123Cd, respectively, with gammasphere by measuring three-and higher-fold prompt coincidences following the spontaneous fission of ²⁵²Cf. The new data suggests that the 11/2⁻ isomers in the odd-A Cd isotopes with N ≥ 75 have spherical shape similar to those in Te. It is suggested that the backbending observed at ℏω ≈ 0.445 MeV in ¹²¹Cd is because of the alignment of the h_11/2 neutron pair.

This paper presents a study of theγ rays from the electron capture decay of 3.63d100Pd. Singles and coincidence measurements provided an accurate determination ofγ-ray intensities and an improved knowledge of the100Rh level scheme. Experimental evidence supports excitation of levels in100Rh at 86-, 136- and 154 keV, not previously reported from the decay of100Pd.

The production of nitrogen and carbon fragments in the reactions induced by16O on144Sm and154Sm targets was studied at two bombarding energies (65 MeV and 72 MeV) around the interaction barrier. The measured angular distributions exhibit the characteristic behaviour of direct transfer reactions, and theQ-value spectra are typically centered at the values predicted by kinematic selectivity. The comparison between fusion and charged-particle transfer cross sections shows that whereas fusion is the most important process at the highest bombarding energy, transfer reactions become comparable or even dominant (as in the144Sm case) at near-barrier energies. The different transfer probabilities observed for the two systems are analyzed in terms of nuclear deformation.

High spin states in97Rh were excited via the96Ru (a,2np) reaction at 45 MeV. As a main finding we have observed a positive parity band, built on the 9/2+ ground state, which depopulated levels at 3,550.7 (25/2+), 3,259.1 (23/2+), 2,895.1 (23/2+), 1,961.3 (19/2+), 1,553.1 (17/2+) and 857.1 (13/2+). Also we have excited levels at 3,055.8 (21/2), 2,225.4 (17/2) and 1,463.5 (15/2), which most likely are negative parity states.

Isotopic assignment of high-spin cascades in98Rh and98Pd have unambigously been obtained by a suitable combination of the96Ru(a, xn yp) and the99Ru(d, xn yp) reactions. As a result the band headed by the 841.3 keV line was assigned to98Rh and the one headed by the 862.6 keV?-ray has been found to belong to98Pd. In the case of98Rh the band is based on the (2+) ground state.

Evaluated spectroscopic data from radioactive decay and reaction studies are given for all nuclei with mass number A = 175. Adopted nuclear structure and radiation information is presented in tabular and decay scheme form. This evaluation for A = 175 supersedes the earlier one by M. M. Minor (76MI07), published in Nuclear Data Sheets 18, 331 (1976).Copyright 1993, 1999 Academic Press

The critical point solution of the pairing phase transition from vibrational to rotational regimes and an application to lead isotopes are described. Suggestions on how to confirm the validity of the E(2) model with transfer reactions using weakly-bound beams are discussed.

Abstract.: The critical point solution of the pairing phase transition from vibrational to rotational regimes and an application to lead isotopes are described. Suggestions on how to confirm the validity of the E(2) model with transfer reactions using weakly-bound beams are discussed.

High-spin states in192Pb were populated via the reaction173Yb(24Mg,5n) at a beam energy of 140 MeV, and the resulting?-rays were deteced using GAMMASPHERE. A previously observed superdeformed band in192Pb has been confirmed.

High-spin states of the isospin Tz= − 1/2 nucleus 55Ni have been identified for the first time by means of the reaction 28Si(36Ar,2αn) at 143 MeV beam energy. The Gammaspherearray together with ancillary detectors was used to detect γrays in coincidence with evaporated light particles. The level scheme of 55Ni comprising four transitions is compared to its mirror partner 55Co and shell-model calculations in the fpshell.

A new superdeformed band, identified in data from the24Mg+173Yb reaction, is assigned to192Pb on the basis of excitation function and coincidence results. Properties of this band are discussed briefly, and compared to the superdeformed bands known in other Pb nuclei.

Two superdeformed (SD) bands have been found and assigned to195Tl on the basis of excitation function and cross bombardment results. The two bands are almost identical in transition energies to those observed in193Tl. They are signature partners with a splitting, presumably due to the proton i13/2 (O=5/2) orbital, characteristic of all known SD bands in the thallium isotopes. Their alignments relative to the193Tl bands were found to be zero.

Lifetimes of superdeformed states in194Pb were measured by the Doppler-shift attenuation method. Quadrupole moments around 20 eb, that are constant over the observed frequency range, are derived. The results rule out large centrifugal stretching effects.