Probing ^{93m}Mo Isomer Depletion with an Isomer Beam.

The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC).

Absence of Low-Energy Shape Coexistence in ^{80}Ge: The Nonobservation of a Proposed Excited 0_{2}^{+} Level at 639 keV.

The ^{80}Ge structure was investigated in a high-statistics β-decay experiment of ^{80}Ga using the GRIFFIN spectrometer at TRIUMF-ISAC through γ, β-e, e-γ, and γ-γ spectroscopy. No evidence was found for the recently reported 0_{2}^{+} 639-keV level suggested as evidence for low-energy shape coexistence in ^{80}Ge. Large-scale shell model calculations performed in ^{78,80,82}Ge place the 0_{2}^{+} level in ^{80}Ge at 2 MeV.

Isospin Properties of Nuclear Pair Correlations from the Level Structure of the Self-Conjugate Nucleus ^{88}Ru.

The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{44} has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states.

Lifetime Measurements of Excited States in ^{172}Pt and the Variation of Quadrupole Transition Strength with Angular Momentum.

Lifetimes of the first excited 2^{+} and 4^{+} states in the extremely neutron-deficient nuclide ^{172}Pt have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:4_{1}^{+}→2_{1}^{+})/B(E2:2_{1}^{+}→0_{gs}^{+})=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart.

_{36}^{96}Kr_{60}-Low-Z Boundary of the Island of Deformation at N=60.

Prompt γ-ray spectroscopy of the neutron-rich ^{96}Kr, produced in transfer- and fusion-induced fission reactions, has been performed using the combination of the Advanced Gamma Tracking Array and the VAMOS++ spectrometer. A second excited state, assigned to J^{π}=4^{+}, is observed for the first time, and a previously reported level energy of the first 2^{+} excited state is confirmed. The measured energy ratio R_{4/2}=E(4^{+})/E(2^{+})=2.

Transverse wobbling in ^{135}pr.

A pair of transverse wobbling bands is observed in the nucleus ^{135}Pr. The wobbling is characterized by ΔI=1, E2 transitions between the bands, and a decrease in the wobbling energy confirms its transverse nature. Additionally, a transition from transverse wobbling to a three-quasiparticle band comprised of strong magnetic dipole transitions is observed.

Search for the pygmy dipole resonance in 68Ni at 600 MeV/nucleon.

The gamma decay from Coulomb excitation of 68Ni at 600 MeV/nucleon on a Au target was measured using the RISING setup at the fragment separator of GSI. The 68Ni beam was produced by a fragmentation reaction of 86Kr at 900 MeV/nucleon on a 9Be target and selected by the fragment separator. The gamma rays produced at the Au target were measured with HPGe detectors at forward angles and with BaF2 scintillators at backward angles.

Risk of misinterpretation of nearly degenerate pair bands as chiral partners in nuclei.

The experimental information on the observed nearly degenerate bands in the N = 75 isotones, in particular 134Pr and 136Pm, which are often considered as the best candidates for chiral bands, is critically analyzed. Most properties of the bands, in particular, the recently measured branching ratios and lifetimes, are in clear disagreement with the interpretation of the two bands as chiral bands. For I =14-18 in 134Pr, where the observed energies are almost degenerate, we have obtained a value of 2.

Transition probabilities in 134Pr: a test for chirality in nuclear systems.

Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F,4n)134Pr. Recoil distance Doppler-shift and Doppler-shift attenuation measurements using the Euroball spectrometer, in conjunction with the inner Bismuth Germanate ball and the Cologne plunger, were performed at beam energies of 87 MeV and 83 MeV, respectively. Reduced transition probabilities in 134Pr are compared to the predictions of the two quasiparticle + triaxial rotor and interacting boson fermion-fermion models.

Compound and rotational damping in warm deformed rare-earth nuclei.

The gamma decay in the quasicontinuum from selected configurations of the rotational nucleus 163Er has been measured with the EUROBALL array. A new analysis technique has allowed for the first time to directly measure the compound and rotational damping widths Gamma (micro) and Gamma (rot). Values of Gamma (micro) approximately 20 keV and Gamma (rot) approximately 200 keV are obtained in the spin region I approximately 30-40 variant Planck's over 2pi, in good agreement with microscopic cranked shell model calculations.

Evidence for second-phonon nuclear wobbling.

The nucleus 163Lu has been populated through the reaction 139La(29Si,5n) with a beam energy of 157 MeV. Three triaxial, strongly deformed (TSD) bands have been observed with very similar rotational properties. The first excited TSD band has earlier been assigned as a one-phonon wobbling excitation built on the lowest-lying (yrast) TSD band.

Evidence for the wobbling mode in nuclei.

The nucleus (163)Lu has been populated through the fusion-evaporation reaction (139)La((29)Si,5n)(163)Lu with a beam energy of 152 MeV. The electromagnetic properties of several connecting transitions between two presumably triaxial, strongly deformed (TSD) bands have been studied. Evidence is presented for the assignment of the excited TSD band as a wobbling mode built on the yrast TSD band, based on comparisons to new calculations in which an aligned particle is coupled to a strongly deformed triaxial rotor.