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The evaluated experimental data are presented for 14 known nuclides of mass 87 (Ga, Ge, As, Se, Br, Kr, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru). New datasets have been added for 87 Ga, 87 Se, 87 Kr, 87 Rb, 87 Sr, 87 Nb, and 87 Tc. The observation of and new lifetime measurements for 87 As at the NSCL Coupled Cyclotron Facility and the Oak Ridge Isochronous Cyclotron at the HRIBF–ORNL Facility are included in the adopted levels for this isotope. The new evaluation also includes an isomeric level at unknown energy for 87 Tc, changes to the adopted levels for 87 Nb based on newly published data including an extension of the high spin levels and new lifetime measurements, and new heavy ion data for 87 Kr. New high spin levels for 87 Rb were observed, indicating possible neutron core excitations. In addition, the ground state lifetime of 87 Rb has been revised and a new lifetime measurement for an excited level in 87 Rb indicates a possible proton spin flip. New excitation levels have been observed for the first time in 87 Se. New direct and precise measurement of atomic masses of 87 Tc, 87 Mo, 87 Nb, 87 Zr, 87 Mo and 87 Tc have greatly improved the Q value landscape in this mass region. This work supersedes the previous A=87 evaluation published in 2002He09, and Q values for all isotopes were updated to incorporate the mass evaluation in 2012Wa38. [ABSTRACT FROM AUTHOR]

Abstract: A general technique that corrects -ray gated decay-curve data for detector pulse pile-up is presented. The method includes corrections for non-zero time-resolution and energy-threshold effects in addition to a special treatment of saturating events due to cosmic rays. This technique is verified through a Monte Carlo simulation and experimental data using radioactive beams of implanted at the center of the -ray spectrometer at the ISAC facility at TRIUMF in Vancouver, Canada. The -decay half-life of obtained from counting 1809-keV -ray photopeaks emitted by the daughter was determined to be following a correction for detector pulse pile-up. This result is in excellent agreement with the result of a previous measurement that employed direct counting and demonstrates the feasibility of high-precision -decay half-life measurements through the use of high-purity germanium -ray detectors. The technique presented here, while motivated by superallowed-Fermi decay studies, is general and can be used for all half-life determinations (e.g. -, -, X-ray, fission) in which a -ray photopeak is used to select the decays of a particular isotope. [Copyright &y& Elsevier]

The properties of high-K isomers have been investigated by measuring γ rays from a source of the 31-year 178Hfm2 isomer and from the decay of implanted 178, 179Lu beams. Low-intensity transitions have been identified in the decay of 178Hfm2, demonstrating a consistent extension of K-hindrance systematics to higher multipolarities, and elucidating the spin-dependence of the mixing between the two Kπ = 8- bands. A search is underway for new isomers in 178, 179Lu and the preliminary results of the analysis are reported. [Copyright &y& Elsevier]