582 research outputs found

    Few-Shot Out-of-Domain Transfer Learning of Natural Language Explanations in a Label-Abundant Setup

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    Training a model to provide natural language explanations (NLEs) for its predictions usually requires the acquisition of task-specific NLEs, which is time- and resource-consuming. A potential solution is the few-shot out-of-domain transfer of NLEs from a parent task with many NLEs to a child task. In this work, we examine the setup in which the child task has few NLEs but abundant labels. We establish four few-shot transfer learning methods that cover the possible fine-tuning combinations of the labels and NLEs for the parent and child tasks. We transfer explainability from a large natural language inference dataset (e-SNLI) separately to two child tasks: (1) hard cases of pronoun resolution, where we introduce the small-e-WinoGrande dataset of NLEs on top of the WinoGrande dataset, and (2) commonsense validation (ComVE). Our results demonstrate that the parent task helps with NLE generation and we establish the best methods for this setup

    Precision Measurement of 11Li moments: Influence of Halo Neutrons on the 9Li Core

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    The electric quadrupole moment and the magnetic moment of the 11Li halo nucleus have been measured with more than an order of magnitude higher precision than before, |Q| = 33.3(5)mb and mu=3.6712(3)mu_N, revealing a 8.8(1.5)% increase of the quadrupole moment relative to that of 9Li. This result is compared to various models that aim at describing the halo properties. In the shell model an increased quadrupole moment points to a significant occupation of the 1d orbits, whereas in a simple halo picture this can be explained by relating the quadrupole moments of the proton distribution to the charge radii. Advanced models so far fail to reproduce simultaneously the trends observed in the radii and quadrupole moments of the lithium isotopes.Comment: 4 pages, 4 figures, 1 tabl

    Spectroscopic distinction between the normal state pseudogap and the superconducting gap of cuprate high T_{c} superconductors

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    We report on broad-band infrared ellipsometry measurements of the c-axis conductivity of underdoped RBa_{2}Cu_{3}O_{7-d} (R=Y, Nd, and La) single crystals. Our data provide a detailed account of the spectral weight (SW) redistributions due to the normal state pseudogap (PG) and the superconducting (SC) gap. They show that these phenomena involve different energy scales, exhibit distinct doping dependencies and thus are likely of different origin. In particular, the SW redistribution in the PG state closely resembles the one of a conventional charge- or spin density wave (CDW or SDW) system.Comment: 4 pages, 4 figure

    Manifestation of pseudogap in ab-plane optical characteristics

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    A model in which a gap forms in the renormalized electronic density of state (DOS) with missing states recovered just above the pseudogap Δpg\Delta_{pg}, is able to give a robust description of the striking, triangular like, peak seen in the real part of the optical self-energy of underdoped cuprates. We use this model to explore the effect of the pseudogap on the real part of the optical conductivity and on the partial sum rule associated with it. An important result is that the optical spectral weight redistributes over a much larger frequency window than it does in the DOS.Comment: 12 pages, 3 figures. Submitted to Journal of Physics: Condensed Matte

    Production of new neutron-rich isotopes of heavy elements in fragmentation reactions of 238^{238}U projectiles at 1 A GeV

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    The production of heavy neutron-rich nuclei has been investigated using cold fragmentation reactions of 238^{238}U projectiles at relativistic energies. The experiment performed at the high-resolving-power magnetic spectrometer FRS at GSI allowed to identify 45 new heavy neutron-rich nuclei: 205^{205}Pt, 207−210^{207-210}Au, 211−216^{211-216}Hg, 213−217^{213-217}Tl, 215−220^{215-220}Pb, 219−224^{219-224}Bi, 221−227^{221-227}Po, 224−229^{224-229}At, 229−231^{229-231}Rn and 233^{233}Fr. The production cross sections of these nuclei were also determined and used to benchmark reaction codes that predict the production of nuclei far from stability.Comment: 5 pages, 2 figure

    Nuclear Charge Radius of 12^{12}Be

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    The nuclear charge radius of 12^{12}Be was precisely determined using the technique of collinear laser spectroscopy on the 2s1/2→2p1/2,3/22s_{1/2}\rightarrow 2p_{1/2, 3/2} transition in the Be+^{+} ion. The mean square charge radius increases from 10^{10}Be to 12^{12}Be by \delta ^{10,12} = 0.69(5) \fm^{2} compared to \delta ^{10,11} = 0.49(5) \fm^{2} for the one-neutron halo isotope 11^{11}Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of 12^{12}Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure.Comment: 5 pages, 3 figure

    Biosynthetic Cause of in Vivo

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    Ground-State Electromagnetic Moments of Calcium Isotopes

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    High-resolution bunched-beam collinear laser spectroscopy was used to measure the optical hyperfine spectra of the 43−51^{43-51}Ca isotopes. The ground state magnetic moments of 49,51^{49,51}Ca and quadrupole moments of 47,49,51^{47,49,51}Ca were measured for the first time, and the 51^{51}Ca ground state spin I=3/2I=3/2 was determined in a model-independent way. Our results provide a critical test of modern nuclear theories based on shell-model calculations using phenomenological as well as microscopic interactions. The results for the neutron-rich isotopes are in excellent agreement with predictions using interactions derived from chiral effective field theory including three-nucleon forces, while lighter isotopes illustrate the presence of particle-hole excitations of the 40^{40}Ca core in their ground state.Comment: Accepted as a Rapid Communication in Physical Review
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