44 research outputs found

    Direct high-precision mass spectrometry of superheavy elements with SHIPTRAP

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    Direct mass measurements in the region of the heaviest elements were performed with the Penning-trap mass spectrometer SHIPTRAP at GSI Darmstadt. Utilizing the phase-imaging ion-cyclotron-resonance massspectrometry technique, the atomic masses of 251No (Z = 102), 254Lr (Z = 103), and 257Rf (Z = 104) available at rates down to one detected ion per day were determined directly for the first time. The ground-state masses of 254No and 255,256Lr were improved by more than one order of magnitude. Relative statistical uncertainties as low as δm/m ≈ 10−9 were achieved. Mass resolving powers of 11 000 000 allowed resolving long-lived low-lying isomeric states from their respective ground states in 251,254No and 254,255Lr. This provided an unambiguous determination of the binding energies for odd-A and odd-odd nuclides previously determined only indirectly from decay spectroscopy.Federal Ministry of Education & Research (BMBF) 05P15HGFNA 05P19HGFNA 05P21HGFN1 05P15UMFNA 05P21UMFN1Max Planck SocietyFoundation CELLEXNetherlands Organization for Scientific Research (NWO) 680-91-103European Commission under Marie Sklodowska-Curie Action FP7 MSC COFUND scheme European Research Council (ERC) 819957Ministry of Science and Innovation, Spain (MICINN) Spanish Government FPA2015-67694-P PID2019-104093GB-I00/AE

    Public awareness of and attitudes towards research biobanks in Latvia

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    Background: Public awareness and engagement are among the main prerequisites for protecting the rights of research participants and for successful and sustainable functioning of research biobanks. The aim of our study was to analyse public awareness and attitudes towards research biobanks in Latvia, and to compare these data with the results of the 2010 Eurobarometer study. We also analysed the influence of awareness and attitudes towards biobanks on willingness to participate in biobank studies and on preferred type of informed consent. Methods: We developed a 12-question survey repeating seven questions about biobanks from the 2010 Eurobarometer questionnaire and adding five others. After describing the study variables, we performed a two-stage analysis of the results. In the first stage we analysed differences between the answers from 2010 and 2019 and conducted univariate analyses of relationships among particular variables, and between those variables and the socio-demographic characteristics of participants. In the second stage we investigated multivariable associations of willingness to participate and type of consent with awareness, trust and the socio-economic characteristics of participants. Results: According to our study, the general public in Latvia is still not well informed about research biobanks. Fewer respondents have heard about research biobanks than in 2010. At the same time, the number of respondents who are willing to donate biological samples and personal data to a biobank has increased, e.g. the number of respondents who would definitely or probably be willing to provide information about themselves has increased from 25.8.% to 40.7 since 2010. Overall, concerns about the donation of different types of biological samples and data to a biobank have slightly decreased. Conclusions: Public awareness about biobanks is important for their sustainability. It needs to be increased not only by traditional methods of informing the public, but also by more innovative and participatory approaches, e.g. by citizen science projects. There is a need to strengthen the public visibility and trustworthiness of ethics committees in Latvia in the field of biobanking

    The TRAPSENSOR facility: an open-ring 7 tesla Penning trap for laserbased precision experiments

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    APenning-trap facility for high-precision mass spectrometry based on a novel detection method has been built. This method consists in measuring motional frequencies of singly-charged ions trapped in strong magnetic fields through the fluorescence photons from laser-cooled 40Ca+ ions, to overcome limitations faced in electronic single-ion detection techniques. The key element of this facility is an open-ring Penning trap coupled upstream to a preparation Penning trap similar to those used at Radioactive Ion Beam facilities. Here we present a full characterization of the trap and demonstrate motional frequency measurements of trapped ions stored by applying external radiofrequency fields in resonance with the ions’ eigenmotions, in combination with time-of-flight identification. The infrastructure developed to observe the fluorescence photons from 40Ca+, comprising the 12 laser beams and the optical system to register the image in a high-sensitive CCD sensor, has been proved by taking images of the trapped and cooled 40Ca+ ions. This demonstrates the functionality of the proposed laser-based mass-spectrometry technique, providing a unique platform for precision experiments with implications in different fields of physics.This work was supported by the European Research Council (contract no. 278648-TRAPSENSOR), from the SpanishMINECO/ FEDER (project nos. FPA2012-32076, FPA2015-67694-P, FIS2015-69983-P, UNGR10-1E- 501, UNGR13-1E-1830), Ramón y Cajal Grant RYC-2012-11391, Juan de la Cierva grant IJCI-2015-26091, Centro Nacional de Partículas, Astropartículas y Nuclear CPAN13-TM01, and ‘Sistema Nacional de Garantía Juvenil y del Programa Operativo de Empleo Juvenil’; from the SpanishMECD(PhD grant nos. FPU15-04679 and FPU17/02596); from Junta de Andalucía/FEDER (project no. IE-57131) and ‘Programa de Empleo Juvenil; from Basque Government (PhD grant no. PRE-2015-1-0394) and (project no. IT986-16), and from the University of Granada ‘Plan propio-Programa de Intensificación de la Investigación PP2017-PRI.I-04’. I.A, L.L. and E.S acknowledge also support from projects OpenSuperQ (820363) and QMiCS (820505) of the EUFlagship on Quantum Technologies

    Precision Measurement of the First Ionization Potential of Nobelium

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    One of the most important atomic properties governing an element’s chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626   21 ± 0.000   05     eV . This work provides a stringent benchmark for state-of-the-art many-body atomic modeling that considers relativistic and quantum electrodynamic effects and paves the way for high-precision measurements of atomic properties of elements only available from heavy-ion accelerator facilities

    Research of the NUSTAR departments : SHE departments and HIM SHE section

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    The SHE departments devoted to the research of superheavy elements, operate the recoil separators SHIP and TASCA and their ancillary installations including SHIPTRAP and a laser spectroscopy setup at SHIP as well as chemistry and nuclear spectroscopy setups at TASCA. In 2019, the activities at GSI focused on the UNILAC beamtime within the FAIR Phase-0 program and on the analysis of data obtained in prior beamtimes. At HIM, the advancement of actinide sample preparation, manipulation, and characterization for various applications was most central. In addition, technical developments, for example for single-ion mass measurements, have been performed

    International students and further education colleges in England: The context, policy tensions, and some aspects of practice

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    This chapter sets out the context of publicly funded further education colleges in England, outlining the position and development of these complex institutions within the broader educational structure. This is followed by discussion of some tensions and contradictions which arise from government policies partially driven by anxieties derived from debates surrounding levels of immigration together with recognition of the imperatives and opportunities arising from globalisation. The benefits of the internationalisation of education have been expounded whilst simultaneously enforcing visa regulations which impede the efforts of colleges to make inroads in the international student market. In particular, disparities between the treatment of the further and higher education sectors are highlighted. The paper also provides an account of practices which have emerged in a single FE college in England over a decade of working with international students following an access to HE course. The chapter indicates some of the many benefits which have been brought to FE by international students as well as the ways in which a college has developed its practices in response to their needs

    Low-lying octupole isovector excitation in Nd-144

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    International audienceThe nature of low-lying 3− levels in Nd144 was investigated in the Nd143(n,γγ) cold neutron-capture reaction. The combination of the high neutron flux from the research reactor at the Institut Laue-Langevin and the high γ-ray detection efficiency of the EXILL setup allowed the recording of γγ coincidences. From the coincidence data precise branching ratios were extracted. Furthermore, the octagonal symmetry of the setup allowed angular-distribution measurements to determine multipole-mixing ratios. Additionally, in a second measurement the ultra-high resolution spectrometer GAMS6 was employed to conduct lifetime measurements using the gamma-ray induced Doppler-shift technique (GRID). The confirmed strong M1 component in the 33−→31− decay strongly supports the assignment of the 33− level at 2779keV as low-lying isovector octupole excitation. Microscopic calculations within the quasiparticle phonon model confirm an isovector component in the wave function of the 33− level, firmly establishing this fundamental mode of nuclear excitation in near-spherical nuclei

    Probing Sizes and Shapes of Nobelium Isotopes by Laser Spectroscopy

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    Until recently, ground-state nuclear moments of the heaviest nuclei could only be inferred from nuclear spectroscopy, where model assumptions are required. Laser spectroscopy in combination with modern atomic structure calculations is now able to probe these moments directly, in a comprehensive and nuclear-model-independent way. Here we report on unique access to the differential mean-square charge radii of 252, 253, 254No, and therefore to changes in nuclear size and shape. State-of-the-art nuclear density functional calculations describe well the changes in nuclear charge radii in the region of the heavy actinides, indicating an appreciable central depression in the deformed proton density distribution in 252, 254No isotopes. Finally, the hyperfine splitting of 253No was evaluated, enabling a complementary measure of its (quadrupole) deformation, as well as an insight into the neutron single-particle wave function via the nuclear spin and magnetic moment
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