567 research outputs found

    Isomeric states close to doubly magic 132^{132}Sn studied with JYFLTRAP

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    The double Penning trap mass spectrometer JYFLTRAP has been employed to measure masses and excitation energies for 11/2−11/2^- isomers in 121^{121}Cd, 123^{123}Cd, 125^{125}Cd and 133^{133}Te, for 1/2−1/2^- isomers in 129^{129}In and 131^{131}In, and for 7−7^- isomers in 130^{130}Sn and 134^{134}Sb. These first direct mass measurements of the Cd and In isomers reveal deviations to the excitation energies based on results from beta-decay experiments and yield new information on neutron- and proton-hole states close to 132^{132}Sn. A new excitation energy of 144(4) keV has been determined for 123^{123}Cdm^m. A good agreement with the precisely known excitation energies of 121^{121}Cdm^m, 130^{130}Snm^m, and 134^{134}Sbm^m has been found.Comment: 10 pages, 6 figures, submitted to Phys. Rev.

    Anxiety onset in adolescents : a machine-learning prediction

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    Publisher Copyright: © 2022, The Author(s).Recent longitudinal studies in youth have reported MRI correlates of prospective anxiety symptoms during adolescence, a vulnerable period for the onset of anxiety disorders. However, their predictive value has not been established. Individual prediction through machine-learning algorithms might help bridge the gap to clinical relevance. A voting classifier with Random Forest, Support Vector Machine and Logistic Regression algorithms was used to evaluate the predictive pertinence of gray matter volumes of interest and psychometric scores in the detection of prospective clinical anxiety. Participants with clinical anxiety at age 18–23 (N = 156) were investigated at age 14 along with healthy controls (N = 424). Shapley values were extracted for in-depth interpretation of feature importance. Prospective prediction of pooled anxiety disorders relied mostly on psychometric features and achieved moderate performance (area under the receiver operating curve = 0.68), while generalized anxiety disorder (GAD) prediction achieved similar performance. MRI regional volumes did not improve the prediction performance of prospective pooled anxiety disorders with respect to psychometric features alone, but they improved the prediction performance of GAD, with the caudate and pallidum volumes being among the most contributing features. To conclude, in non-anxious 14 year old adolescents, future clinical anxiety onset 4–8 years later could be individually predicted. Psychometric features such as neuroticism, hopelessness and emotional symptoms were the main contributors to pooled anxiety disorders prediction. Neuroanatomical data, such as caudate and pallidum volume, proved valuable for GAD and should be included in prospective clinical anxiety prediction in adolescents.Peer reviewe

    Characterization of a Be(p,xn) neutron source for fission yields measurements

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    We report on measurements performed at The Svedberg Laboratory (TSL) to characterize a proton-neutron converter for independent fission yield studies at the IGISOL-JYFLTRAP facility (Jyv\"askyl\"a, Finland). A 30 MeV proton beam impinged on a 5 mm water-cooled Beryllium target. Two independent experimental techniques have been used to measure the neutron spectrum: a Time of Flight (TOF) system used to estimate the high-energy contribution, and a Bonner Sphere Spectrometer able to provide precise results from thermal energies up to 20 MeV. An overlap between the energy regions covered by the two systems will permit a cross-check of the results from the different techniques. In this paper, the measurement and analysis techniques will be presented together with some preliminary results.Comment: 3 pages, 3 figures, also submitted as proceedings of the International Conference on Nuclear Data for Science and Technology 201

    Q_EC values of the Superallowed beta-Emitters 10-C, 34-Ar, 38-Ca and 46-V

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    The Q_EC values of the superallowed beta+ emitters 10-C, 34-Ar, 38-Ca and 46-V have been measured with a Penning-trap mass spectrometer to be 3648.12(8), 6061.83(8), 6612.12(7) and 7052.44(10) keV, respectively. All four values are substantially improved in precision over previous results.Comment: 9 pages, 7 figures, 5 table

    Emergence of hybrid CSR models as a conflict‐driven communicative process in a Nordic welfare state

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    This paper offers an understanding of how hybrid models of corporate social responsibility (CSR) – models combining society-centric mandatory (implicit) and business-centric voluntary (explicit) approaches to CSR – are communicatively constructed through institutional struggles over the roles and responsibilities of business in society, in the context of a Nordic welfare state. We develop a model of hybridization as a dialectical process of communicative activity, framing and counter-framing, in which conflict and contestation over normative understandings about CSR drive the process. The model explains the emergence of hybrid models of CSR in terms of gradually evolving issue development and frame changes that are driven by discursive struggles over moral obligations of business in society, appropriate configuration of legitimacy relationships, and appropriate institutional arrangements for CSR governance. In contrast to prevailing accounts, which tend to theorize hybridization as resulting from isomorphic, mimetic, and normative pressures, our account explicitly attends to the politics of hybridization

    Measurement of parity-nonconserving rotation of neutron spin in the 0.734-eV p-wave resonance of 139La^{139}La

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    The parity nonconserving spin rotation of neutrons in the 0.734-eV p-wave resonance of 139La^{139}La was measured with the neutron transmission method. Two optically polarized 3He^3He cells were used before and behind a a 5-cm long 139La^{139}La target as a polarizer and an analyzer of neutron spin. The rotation angle was carefully measured by flipping the direction of 3He^3He polarization in the polarizer in sequence. The peak-to-peak value of the spin rotation was found to be (7.4±1.1)×10−3 (7.4 \pm 1.1) \times 10^{-3} rad/cm which was consistent with the previous experiments. But the result was statisticallly improved. The s-p mixing model gives the weak matrix element as xW=(1.71±0.25)xW = (1.71 \pm 0.25) meV. The value agrees well with the one deduced from the parity-nonconserving longitudinal asymmetry in the same resonance

    Evidence of 4He Crystallization via Quantum Tunneling at mK Temperatures

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    We have investigated creation of 4He crystals from the superfluid phase at the temperature range 2 mK–1.0 K. Statistical nucleation-event distributions in overpressure were found to be broad, asymmetric, and temperature independent below 100 mK. Our statistical analysis agrees with a theoretical model suggesting that solid formation is driven by macroscopical quantum-mechanical fluctuations from a seed preexisting in a cavity on the wall.Peer reviewe

    Electron-capture branch of 100Tc and tests of nuclear wave functions for double-beta decays

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    We present a measurement of the electron-capture branch of 100^{100}Tc. Our value, B(EC)=(2.6±0.4)×10−5B(\text{EC}) = (2.6 \pm 0.4) \times 10^{-5}, implies that the 100^{100}Mo neutrino absorption cross section to the ground state of 100^{100}Tc is roughly one third larger than previously thought. Compared to previous measurements, our value of B(EC)B(\text{EC}) prevents a smaller disagreement with QRPA calculations relevant to double-ÎČ\beta decay matrix elements
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