At the radioactive ion beam facility REX-ISOLDE, neutron-rich zinc isotopes were investigated using lowenergy Coulomb excitation. These experiments have resulted in B(E2, 2 74,76 Zn and the determination of the energy of the first excited 2 + 1 states in 78,80 Zn. The zinc isotopes were produced by high-energy proton-(A = 74, 76, 80) and neutron-(A = 78) induced fission of 238 U, combined with selective laser ionization and mass separation. The isobaric beam was postaccelerated by the REX linear accelerator and Coulomb excitation was induced on a thin secondary target, which was surrounded by the MINIBALL germanium detector array. In this work, it is shown how the selective laser ionization can be used to deal with the considerable isobaric beam contamination and how a reliable normalization of the experiment can be achieved. The results for zinc isotopes and the N = 50 isotones are compared to collective model predictions and state-of-the-art large-scale shell-model calculations, including a recent empirical residual interaction constructed to describe the present experimental data up to 2004 in this region of the nuclear chart.

With the Q3D magnetic spectrograph of the Maier-Leibnitz-Laboratorium at München at a resolution of about 3 keV, angular distributions and excitation functions of the reaction 208 Pb(p,p ) were measured at some scattering angles 20 • -138 • for several proton energies 14.8-18.1 MeV. All seven known isobaric analog resonances in 209 Bi are covered. By the excitation near the j 15/2 intruder resonance in 209 Bi, several new positive parity states in 208 Pb with excitation energies 4.6-6.2 MeV are identified by comparison of the mean cross section to the known single particle widths. The dominant configuration for 27 positive parity states is determined and compared to the schematic shell model.

We report on the first radioactive beam experiment performed at the recently commissioned REX-ISOLDE facility at CERN in conjunction with the highly efficient gamma spectrometer MINIBALL. Using 30Mg ions accelerated to an energy of 2.25 MeV/u together with a thin (nat)Ni target, Coulomb excitation of the first excited 2+ states of the projectile and target nuclei well below the Coulomb barrier was observed. From the measured relative deexcitation gamma-ray yields the B(E2;0(+)gs-->2(+)1) value of 30Mg was determined to be 241(31)e2 fm4. Our result is lower than values obtained at projectile fragmentation facilities using the intermediate-energy Coulomb excitation method, and confirms the theoretical conjecture that the neutron-rich magnesium isotope 30Mg resides outside the "island of inversion."

Neutron-rich, radioactive Zn isotopes were investigated at the Radioactive Ion Beam facility REX-ISOLDE (CERN) using low-energy Coulomb excitation. The energy of the 2(1)+ state in 78Zn could be firmly established and for the first time the 2+ --> 0(1)+ transition in 80Zn was observed at 1492(1) keV. B(E2,2(1)+ --> 0(1)+) values were extracted for (74,76,78,80)Zn and compared to large scale shell model calculations. With only two protons outside the Z=28 proton core, 80Zn is the lightest N=50 isotone for which spectroscopic information has been obtained to date. Two sets of advanced shell model calculations reproduce the observed B(E2) systematics. The results for N=50 isotones indicate a good N=50 shell closure and a strong Z=28 proton core polarization. The new results serve as benchmarks to establish theoretical models, predicting the nuclear properties of the doubly magic nucleus 78Ni.

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Using a method whereby molecular and atomic ions are independently selected, an isobarically pure beam of 70 Se ions was postaccelerated to an energy of 206 MeV using REX-ISOLDE. Coulomb-excitation yields for states in the beam and target nuclei were deduced by recording deexcitation rays in the highly segmented MINIBALL -ray spectrometer in coincidence with scattered particles in a silicon detector. At these energies, the Coulomb-excitation yield for the first 2 state is expected to be strongly sensitive to the sign of the spectroscopic quadrupole moment through the nuclear reorientation effect. Experimental evidence is presented here for a prolate shape for the first 2 state in 70 Se, reopening the question over whether there are, as reported earlier, deformed oblate shapes near to the ground state in the light selenium isotopes. DOI: 10.1103/PhysRevLett.98.072501 PACS numbers: 21.10.Ky, 25.70.De, 27.50.+e A remarkable property of the nucleus is its ability to assume different configurations giving energy minima corresponding to different shapes of the mean field. It is often claimed that the presence of low-lying excited 0 states in even-even nuclei is strong evidence for such shape coexistence, since it is difficult to account for the presence of such states otherwise [1,2]. Arguably the most striking example of this is the case of 186 Pb [3], where both the first and second excited states have a spin parity of 0 . These states were interpreted as the bandheads of oblate and prolate rotational configurations, in close competition with the spherical ground state expected for this singly magic (Z 82) nuclear system. The region close to the N Z line from 56 Ni to 80 Zr is believed to be one of rapidly changing nuclear shape. At the upper end of this region, strongly prolate deformed shapes are found: 80 Zr is suggested to have 2 0:4 on the basis of the high moment of inertia [4], and a strongly prolate ground state, consistent with 2 0:4, has recently been established from the Gamow-Teller strength distribution in 76 Sr [5]. For the midshell nuclei near N Z 34 and 36, large shell gaps exist for protons and neutrons at both prolate and oblate shape, which would favor shape coexistence near the ground state. In the light krypton isotopes, 72-78 Kr, a low-lying excited 0 state is observed. There is good experimental evidence that this state has an oblate intruder configuration, and it most likely becomes the ground state in 72 Kr [6,7]. An analysis of the mixing of this state with the ground state, through consideration of their perturbed energies and the excited state lifetime, suggests an oblate ground state for 72 Kr [6], while the recently measured BE2; 0 ! 2 value in this nucleus, PRL 98,

Study of the implementation and acceptance of the SARS-CoV-2 occupational safety and health standard and the SARS-CoV-2 occupational safety and health rules for successful infection control in companies Objectives: This study is intended to provide insights into the real-life implementation of SARS-CoV-2-related occupational safety and health (OSH) measures in German companies. It should also help to identify possible perspectives for further measures to improve the approach of the German accident insurance institutions in comparable situations and to reduce the burden on employees. Methods: Between December 2020 and May 2021, we conducted an online survey on the implementation of SARS-CoV-2 OSH measures. With the help of various German Social Accident Insurance Institutions, we recruited 344 OSH professionals and 92 other people with OSH responsibility from the public sector, industrial, financial, retail and local public transport sectors, and analysed their responses. Results: Most OSH professionals are familiar with SARS-CoV-2 OSH standards, SARS-CoV-2 OSH rules and sector-specific supplements. In only very rare exceptions (1 %) were the employees not informed of preventive and occupational safety measures that had been initiated. Sector-specific differences were particularly evident in contact reduction measures and the stockholding of protective equipment. The increase in mobile working and the greater use of digital communication media were cited as major longterm consequences of the pandemic on future work types. Conclusions: This study confirms that the importance of occupational and infection protection has increased in the SARS-CoV-2 pandemic. Many companies took infection control measures early in the pandemic. Keywords: coronavirus – COVID-19 – SARS-CoV-2 pandemic – preventive measures – occupational safety and health professionals

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