In-beam gamma-ray spectroscopy of even Mo and Ru isotopes

摘要: Abstract Excited states of 92, 94, 96, 98Mo and 98, 100,102Ru were studied by in-beam γ-ray spectroscopy. The decays levels populated the (α, 2n) reaction on even isotopes Zr Mo measurement γ-singles spectrum, beam-γ-delay, γγ- coincidences (prompt delayed), angular distributions. most notable new feature these experiments is use, in-beam, a sensitive coincidence technique, employing two Ge(Li) spectrometers in conjunction with two-parameter incremental data-acquisition system, to establish placement weak transitions. level schemes are compared previous studies nuclei. A considerable number levels, predominantly high spin (I > 6), observed. observed analyzed terms systematics and, where available, detailed shell-model calculations. general description excitations low-lying orbitals outside 38-proton+50-neutron core appears adequate explain much data, particularly those nuclei near 50-neutron shell. data also recent macroscopic calculations quasi-rotational bands, VMI model. distribution residual indicates net loss momentum emission neutrons and/or unresolved γ-rays. Calculations based microscopic model for neutron evaporation suggest that, moment-of-inertia parameter ∮ = 0.5 ∮rigid, angular-momentum can be accounted entirely neutrons, whereas /t0rigid, some it must reside unplaced