756 research outputs found
Effect of ice sheet interactions in anthropogenic climate change simulations
We investigate the effect of ice sheets on climate change under elevated atmospheric CO2 concentrations with an atmosphere ocean general circulation model ( AOGCM) coupled to a thermomechanical ice sheet model and a vegetation model. The effect of increased meltwater fluxes from ice sheets turned out to be negligible in the phase of initial weakening of the North Atlantic meridional overturning circulation ( AMOC), and more important during the recovery in subsequent centuries. Lower surface height of the Greenland ice sheet ( GRIS) leads locally to a warming, especially in winter, and remotely to a cooling over northern Eurasia due to modified atmospheric circulation. With quadrupling of the atmospheric CO2 concentration the entire GRIS is exposed to surface melt in summer. On formerly ice-covered grid points climate locally warms strongly via increased albedos, with positive feedbacks due to boreal forest expansion
Analysis and results of the 104Sn Coulomb excitation experiment
G. Guastalla, et al. XX International School on Nuclear Physics, Neutron Physics and Applications (Varna 2013); 5 pags.; 1 fig.The analysis of the Coulomb excitation experiment conducted on 104Sn required a strict selection of the data in order to reduce the large background present in the γ-ray energy spectra and identify the γ-ray peak corresponding to the Coulomb excitation events. As a result the B(E2; 0+ →2+) value could be extracted, which established the downward trend towards 100Sn and therefore the robustness of the N=Z=50 core against quadrupole excitations. Published under licence by IOP Publishing LtdA. J. would like to thank the Spanish Ministerio de Ciencia e Innovacion for financial support under Contract No. FPA2011-29854- C04Peer Reviewe
Identification of a millisecond isomeric state in 129Cd81 via the detection of internal conversion and Compton electrons
published_or_final_versio
β-Decay Half-Lives of 110 Neutron-Rich Nuclei across the N = 82 Shell Gap: Implications for the Mechanism and Universality of the Astrophysical r Process
The β-decay half-lives of 110 neutron-rich isotopes of the elements from 37Rb to 50Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell eff
Advancing Decadal-Scale Climate Prediction in the North Atlantic Sector
The climate of the North Atlantic region exhibits fluctuations on decadal timescales that have large societal consequences. Prominent examples include hurricane activity in the Atlantic1, and surface-temperature and rainfall variations over North America2, Europe3 and northern Africa4. Although these multidecadal variations are potentially predictable if the current state of the ocean is known5, 6, 7, the lack of subsurface ocean observations8 that constrain this state has been a limiting factor for realizing the full skill potential of such predictions9. Here we apply a simple approach—that uses only sea surface temperature (SST) observations—to partly overcome this difficulty and perform retrospective decadal predictions with a climate model. Skill is improved significantly relative to predictions made with incomplete knowledge of the ocean state10, particularly in the North Atlantic and tropical Pacific oceans. Thus these results point towards the possibility of routine decadal climate predictions. Using this method, and by considering both internal natural climate variations and projected future anthropogenic forcing, we make the following forecast: over the next decade, the current Atlantic meridional overturning circulation will weaken to its long-term mean; moreover, North Atlantic SST and European and North American surface temperatures will cool slightly, whereas tropical Pacific SST will remain almost unchanged. Our results suggest that global surface temperature may not increase over the next decade, as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming
Deformation of the N=Z nucleus 76Sr using beta-decay studies
A novel method of deducing the deformation of the N=Z nucleus 76Sr is
presented. It is based on the comparison of the experimental Gamow-Teller
strength distribution B(GT) from its beta decay with the results of QRPA
calculations. This method confirms previous indications of the strong prolate
deformation of this nucleus in a totally independent way. The measurement has
been carried out with a large Total Absorption gamma Spectrometer, "Lucrecia",
newly installed at CERN-ISOLDE.Comment: Accepted in Phys. Rev. Letter
β decay of 129 Cd and excited states in 129 In
The β decay of Cd129, produced in the relativistic fission of a U238 beam, was experimentally studied at the RIBF facility at the RIKEN Nishina Center. From the γ radiation emitted after the β decays, a level scheme of In129 was established comprisin
Pair neutron transfer in Ni 60 + Sn 116 probed via Îł -particle coincidences
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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