1,354 research outputs found

    Editorial introduction: How has the pandemic hit the Spanish economy and what should governments do?

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    In 2020, the world was suddenly hit by the most severe global pandemic in a century due to the coronavirus disease (COVID-19), first detected in late 2019. Beyond the health and human tragedy of the disease, the pandemic triggered the most serious global economic crisis since Second World War in terms of speed and intensity. To mitigate the propagation of the virus, governments around the world implemented unprecedented protective strategies, such as restrictions on movement and travel, recurrent population lockdowns and social distancing imposed in shops, eateries, public transport, schools and cultural activities. As a result, hospitality and travel industry has collapsed; businesses have closed, unemployment has skyrocketed, the inequalities in our societies have been exposed; and social isolation has been widely imposed worldwide, which plunged most major economies into recession..

    Testing the convergence hypothesis for OECD countries: A reappraisal

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    This paper reviews the results of a number of empirical studies of convergence among the OECD countries and discusses some limitations of these studies. Moreover, the paper tries to deal with these limitations by presenting a new and more appropriate methodology: quantile regressions. The results obtained with this specification support the view that, even among the OECD countries, there are different clusters. The parameter representing the convergence hypothesis, despite being negative in every case, is higher in value and more significant as we advance to higher quantiles. These outcomes reveal a faster convergence between the countries that belong to the upper quantiles. Moreover, 1960-1970 is highlighted as the period in which convergence was more intense

    Performance of the Fully Digital FPGA-based Front-End Electronics for the GALILEO Array

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    In this work we present the architecture and results of a fully digital Front End Electronics (FEE) read out system developed for the GALILEO array. The FEE system, developed in collaboration with the Advanced Gamma Tracking Array (AGATA) collaboration, is composed of three main blocks: preamplifiers, digitizers and preprocessing electronics. The slow control system contains a custom Linux driver, a dynamic library and a server implementing network services. The digital processing of the data from the GALILEO germanium detectors has demonstrated the capability to achieve an energy resolution of 1.53 per mil at an energy of 1.33 MeV.Comment: 5 pages, 6 figures, preprint version of IEEE Transactions on Nuclear Science paper submitted for the 19th IEEE Real Time Conferenc

    The population of deformed bands in 48^{48}Cr by emission of 8^{8}Be from the 32^{32}S + 24^{24}Mg reaction

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    Using particle-γ\gamma coincidences we have studied the population of final states after the emission of 2 α\alpha-particles and of 8^{8}Be in nuclei formed in 32^{32}S+24^{24}Mg reactions at an energy of EL(32S)=130MeV\textrm{E}_{\rm L}(^{32}\textrm{S}) = 130 {\rm MeV}. The data were obtained in a setup consisting of the GASP γ\gamma-ray detection array and the multidetector array ISIS. Particle identification is obtained from the Δ\DeltaE and E signals of the ISIS silicon detector telescopes, the 8^{8}Be being identified by the instantaneous pile up of the Δ\DeltaE and E pulses. γ\gamma-ray decays of the 48^{48}Cr nucleus are identified with coincidences set on 2 α\alpha-particles and on 8^{8}Be. Some transitions of the side-band with Kπ=4K^\pi=4^{-} show stronger population for 8^{8}Be emission relative to that of 2 α\alpha-particles (by a factor 1.51.81.5-1.8). This observation is interpreted as due to an enhanced emission of 8^{8}Be into a more deformed nucleus. Calculations based on the extended Hauser-Feshbach compound decay formalism confirm this observation quantitatively.Comment: 17 pages, 9 figures accepted for publication in J. Phys.

    Natural Diagonal Riemannian Almost Product and Para-Hermitian Cotangent Bundles

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    We obtain the natural diagonal almost product and locally product structures on the total space of the cotangent bundle of a Riemannian manifold. We find the Riemannian almost product (locally product) and the (almost) para-Hermitian cotangent bundles of natural diagonal lift type. We prove the characterization theorem for the natural diagonal (almost) para-K\"ahlerian structures on the total spaces of the cotangent bundle.Comment: 10 pages, will appear in Czechoslovak Mathematical Journa

    πNN\pi NN coupling determined beyond the chiral limit

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    Within the conventional QCD sum rules, we calculate the πNN\pi NN coupling constant, gπNg_{\pi N}, beyond the chiral limit using two-point correlation function with a pion. We consider the Dirac structure, iγ5i\gamma_5, at mπ2m_\pi^2 order, which has clear dependence on the PS and PV coupling schemes for the pion-nucleon interactions. For a consistent treatment of the sum rule, we include the linear terms in quark mass as they constitute the same chiral order as mπ2m_\pi^2. Using the PS coupling scheme for the pion-nucleon interaction, we obtain gπN=13.3±1.2g_{\pi N}=13.3\pm 1.2, which is very close to the empirical πNN\pi NN coupling. This demonstrates that going beyond the chiral limit is crucial in determining the coupling and the pseudoscalar coupling scheme is preferable from the QCD point of view.Comment: 8 pages, revtex, some errors are corrected, substantially revise

    Clusters in Light Nuclei

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    A great deal of research work has been undertaken in the alpha-clustering study since the pioneering discovery, half a century ago, of 12C+12C molecular resonances. Our knowledge of the field of the physics of nuclear molecules has increased considerably and nuclear clustering remains one of the most fruitful domains of nuclear physics, facing some of the greatest challenges and opportunities in the years ahead. In this work, the occurence of "exotic" shapes in light N=Z alpha-like nuclei is investigated. Various approaches of superdeformed and hyperdeformed bands associated with quasimolecular resonant structures are presented. Results on clustering aspects are also discussed for light neutron-rich Oxygen isotopes.Comment: 12 pages, 5 figures. Invited Talk presented by C. Beck at the Zakopane Conference on Nuclear Physics "Extremes of the Nuclear Landscape" XLV in the series of Zakopane Schools of Physics - International Symposium - Zakopane, Poland, August 30 - September 5, 2010.To be publihed in Acta Physica Polonica B42 no 3, March 201

    Lifetime measurements in 63^{63}Co and 65^{65}Co

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    Lifetimes of the 9/219/2^-_1 and 3/213/2^-_1 states in 63^{63}Co and the 9/219/2^-_1 state in 65^{65}Co were measured using the recoil distance Doppler shift and the differential decay curve methods. The nuclei were populated by multi-nucleon transfer reactions in inverse kinematics. Gamma rays were measured with the EXOGAM Ge array and the recoiling fragments were fully identified using the large-acceptance VAMOS spectrometer. The E2 transition probabilities from the 3/213/2^-_1 and 9/219/2^-_1 states to the 7/27/2^- ground state could be extracted in 63^{63}Co as well as an upper limit for the 9/217/219/2^-_1\rightarrow7/2^-_1 BB(E2) value in 65^{65}Co. The experimental results were compared to large-scale shell-model calculations in the pfpf and pfg9/2pfg_{9/2} model spaces, allowing to draw conclusions on the single-particle or collective nature of the various states.Comment: 8 pages, 8 figures, 1 table, accepted for publication in Physical Review

    DNA Replication Timing Is Maintained Genome-Wide in Primary Human Myoblasts Independent of D4Z4 Contraction in FSH Muscular Dystrophy

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    Facioscapulohumeral muscular dystrophy (FSHD) is linked to contraction of an array of tandem 3.3-kb repeats (D4Z4) at 4q35.2 from 11-100 copies to 1-10 copies. The extent to which D4Z4 contraction at 4q35.2 affects overall 4q35.2 chromatin organization remains unclear. Because DNA replication timing is highly predictive of long-range chromatin interactions, we generated genome-wide replication-timing profiles for FSHD and control myogenic precursor cells. We compared non-immortalized myoblasts from four FSHD patients and three control individuals to each other and to a variety of other human cell types. This study also represents the first genome-wide comparison of replication timing profiles in non-immortalized human cell cultures. Myoblasts from both control and FSHD individuals all shared a myoblast-specific replication profile. In contrast, male and female individuals were readily distinguished by monoallelic differences in replication timing at DXZ4 and other regions across the X chromosome affected by X inactivation. We conclude that replication timing is a robust cell-type specific feature that is unaffected by FSHD-related D4Z4 contraction

    Pair neutron transfer in Ni 60 + Sn 116 probed via γ -particle coincidences

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    D. Montanari et al. ; 6 págs.; 5 figs.; 1 tab.We performed a γ-particle coincidence experiment for the Ni60+Sn116 system to investigate whether the population of the two-neutron pickup channel leading to Ni62 is mainly concentrated in the ground-state transition, as has been found in a previous work [D. Montanari et al., Phys. Rev. Lett. 113, 052501 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.052501]. The experiment has been performed by employing the PRISMA magnetic spectrometer coupled to the Advanced Gamma Tracking Array (AGATA) demonstrator. The strength distribution of excited states corresponding to the inelastic, one- and two-neutron transfer channels has been extracted. We found that in the two-neutron transfer channel the strength to excited states corresponds to a fraction (less than 24%) of the total, consistent with the previously obtained results that the 2n channel is dominated by the ground-state to ground-state transition. ©2016 American Physical SocietyThis work was partly supported by the EU FP7/2007-2013 under Grant No. 262010-ENSAR and by the Croatian Science Foundation under Project No. 7194. A.G. was partially supported by MINECO and Generalitat Valenciana, Spain, under Grants No. FPA2014-57196-C5 and No. PROMETEOII/2014/019 and the EU under the FEDER program.Peer Reviewe
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