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The most recent tabulations of nuclear magnetic dipole and electric quadrupole moments have been prepared and published by the Nuclear Data Section of the IAEA, Vienna [N. J. Stone, Report No. INDC(NDS)-0650 (2013); Report No. IND...
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The most recent tabulations of nuclear magnetic dipole and electric quadrupole moments have been prepared and published by the Nuclear Data Section of the IAEA, Vienna [N. J. Stone, Report No. INDC(NDS)-0650 (2013); Report No. INDC(NDS)-0658 (2014)]. The first of these is a table of recommended quadrupole moments for all isotopes in which all experimental results are made consistent with a limited number of adopted standards for each element; the second is a combined listing of all measurements of both moments. Both tables cover all isotopes and energy levels. In this paper, the considerations relevant to the preparation of both tables are described, together with observations as to the importance and (where appropriate) application of necessary corrections to achieve the "best" values. Some discussion of experimental methods is included with emphasis on their precision. The aim of the published quadrupole moment table is to provide a standard reference in which the value given for each moment is the best available and for which full provenance is given. A table of recommended magnetic dipole moments is in preparation, with the same objective in view. (C) 2015 AIP Publishing LLC.
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A prior theory for high-temperature superconductivity (HTSC) was given based on substances having nuclei of nonzero nuclear magnetic moments (NMM) for strong relativistic reversible, nonclassical scattering of superconducting Coop...
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A prior theory for high-temperature superconductivity (HTSC) was given based on substances having nuclei of nonzero nuclear magnetic moments (NMM) for strong relativistic reversible, nonclassical scattering of superconducting Cooper pairs beyond 40 K limit for recovery of coupling due to nonzero NMM of atoms in heat bath. Type II and type I superconductors were reasoned to involve relativistic, quantal, fractionally fissing, and fusing nuclei of both positive and negative NMM for more effectively transforming thermal energy to gravitational, magnetic, and quantum energies for effecting superconductivity and superfluidity. On the basis of such model, all high-temperature superconductivity was explained and the critical temperature (T-c), and its variation by elemental and isotopic compositions were reasoned. This prior 2005 theory and model is supported by recent 2018 observations of superconductivity in silver nanoparticles of all negative NMM in gold nano-matrix of all positive NMM. New superconductors of elements and compounds are predicted on basis of enriching isotopes of positive and negative NMM in such substances.
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The precise measurement of the muon anomalous magnetic moment a_μ has stimulated much theoretical and experimental efforts over more than six decades. The last experiment at Brookhaven National Laboratory, Upton, NY, USA obtained...
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The precise measurement of the muon anomalous magnetic moment a_μ has stimulated much theoretical and experimental efforts over more than six decades. The last experiment at Brookhaven National Laboratory, Upton, NY, USA obtained a value more than three standard deviations larger than predicted by the Standard Model of particle physics, and is one of the strongest hints for physics beyond the Standard Model. A new experiment at Fermi National Accelerator Laboratory, Batavia, IL, USA to measure aμ with fourfold increased precision to 140 ppb is currently in its commissioning phase. While the new experiment will reuse the 1.45 T superconductingmuon storage ring which was shipped from Brookhaven National Laboratory, most of the other instrumentation of the experiment will be new. This will allow the experiment to make efficient use of the significantly higher number of muons available at the new muon campus. We discuss the general status of the experiment and in particular focus on the improved tools available to homogenize and determine the magnetic field in the muon storage ring.
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A nuclear magnetic resonance (NMR) spectrometer for determining the resonance frequencies of various nuclei at a magnetic field induction of 2.142 T is described The spectrometer enables the NMR frequency of a nucleus to be record...
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A nuclear magnetic resonance (NMR) spectrometer for determining the resonance frequencies of various nuclei at a magnetic field induction of 2.142 T is described The spectrometer enables the NMR frequency of a nucleus to be recorded simultaneously with the frequency of the signal from a comparison nucleus and enables the magnetic field to be stabilized using the NMR signal from a third nucleus. The ratios of the resonance frequencies of protons and of the lithium-7 nuclei: F(H_2O)F(~7Li) = 2.573041789(3) are obtained for a solution of lithium chloride in water, and also the ratio for protons and deuterons of an isotopic solution of water: F(H_2O)/F(D_2O) = 6.514399603(2). Methods of determining the systematic errors which occur when there are quadratic gradients of the magnetic field in the sample when processing spectral numerical data matrices are discussed.
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A CP-violating interaction of the nuclear magnetic quadrupole moment (MQM) with electrons in the ytterbium monohydroxide molecule ~(173)YbOH is considered. Both the MQM of the ~(173)Yb nucleus and the molecular interaction constan...
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A CP-violating interaction of the nuclear magnetic quadrupole moment (MQM) with electrons in the ytterbium monohydroxide molecule ~(173)YbOH is considered. Both the MQM of the ~(173)Yb nucleus and the molecular interaction constant W_M are estimated. Electron correlation effects are taken into account within the relativistic Fock-space coupled-cluster method. Results are interpreted in terms of the strength constants of CP-violating nuclear forces, neutron dipole moment (EDM), QCD vacuum angle θ, quark EDMs, and chromo-EDMs.
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Measurements of nuclear magnetic dipole and electric quadrupole moments are considered quite important for the understanding of nuclear structure both near and far from the valley of stability. The recent advent of radioactive bea...
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Measurements of nuclear magnetic dipole and electric quadrupole moments are considered quite important for the understanding of nuclear structure both near and far from the valley of stability. The recent advent of radioactive beams has resulted in a plethora of new, continuously flowing, experimental data on nuclear structure - including nuclear moments - which hinders the information management. A new, dedicated, public and user friendly online database has been created comprising experimental data of nuclear electromagnetic moments. The present database supersedes existing printed compilations, including also non-evaluated series of data and relevant meta-data, while putting strong emphasis on bimonthly updates. The scope, features and extensions of the database are reported.
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We describe a method based on precision magnetometry that can extend the search for axion-mediated spin-dependent forces by several orders of magnitude. By combining techniques used in nuclear magnetic resonance and short-distance...
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We describe a method based on precision magnetometry that can extend the search for axion-mediated spin-dependent forces by several orders of magnitude. By combining techniques used in nuclear magnetic resonance and short-distance tests of gravity, our approach can substantially improve upon current experimental limits set by astrophysics, and probe deep into the theoretically interesting regime for the Peccei-Quinn (PQ) axion. Our method is sensitive to PQ axion decay constants between 10~9 and 10~(12) GeV or axion masses between 10~(-6) and 10~(-3) eV, independent of the cosmic axion abundance.
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This paper reports the results of numerical modeling of the magnetic dipole moment produced by displacement of the Earth's magnetic field in a one-kiloton underground nuclear explosion in a cavity. It is shown that with increase i...
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This paper reports the results of numerical modeling of the magnetic dipole moment produced by displacement of the Earth's magnetic field in a one-kiloton underground nuclear explosion in a cavity. It is shown that with increase in cavity size, the magnetic dipole moment increases, reaching 10~7 A · m~2, which is approximately 200 times the magnetic dipole moment from a camouflet explosion. A factor of 100 decrease in the initial air density in cavities with radii of 10 and 20 m results in a reversal of the direction of the magnetic dipole moment vector.
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We use the nuclear density functional theory to determine nuclear electric quadrupole and magnetic dipole moments in all one-particle and one-hole neighbours of eight doubly magic nuclei. We align angular momenta along the intrins...
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We use the nuclear density functional theory to determine nuclear electric quadrupole and magnetic dipole moments in all one-particle and one-hole neighbours of eight doubly magic nuclei. We align angular momenta along the intrinsic axial-symmetry axis with broken time-reversal symmetry, which allows us to explore fully the self-consistent charge, spin, and current polarisation. Spectroscopic moments are determined for symmetry-restored wave functions and compared with available experimental data. We find that the obtained polarisations do not call for using quadrupole- or dipole-moment operators with effective charges or effective g-factors.
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A new experiment is constructed aiming at the first direct high-precision measurement of the helium-3 nuclear magnetic moment with a relative precision of parts-per-billion or better. Methods similar to those used in proton and an...
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A new experiment is constructed aiming at the first direct high-precision measurement of the helium-3 nuclear magnetic moment with a relative precision of parts-per-billion or better. Methods similar to those used in proton and antiproton magnetic moment measurements are applied. As those techniques rely on the challenging detection of single spin-flips, a novel Penning trap design optimized for nuclear spin-flip detection is developed.
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