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Nuclear isovector valence-shell excitation of Hg 202
Excited states of 202 Hg have been studied via the 12 C( 202 Hg, 202 Hg*) Coulomb excitation reaction at a beam energy of 890 MeV. The γ-ray transitions from the excited states of 202 Hg were detected by the Gammasphere array. The intensities of the observed γ rays determined the relative populations of the excited states which were used to extract the absolute M 1 and E 2 transition strength distributions for excited 2 + states of 202 Hg up to 2 MeV. The measured absolute B ( M 1;2 + 7 →2 + 1 ) strength of 0.18(8)μ 2 N indicates that the 2 + 7 level of 202 Hg is the main fragment of the proton-neutron mixed-symmetry 2 + 1,ms state. As a result, the upper limits for the F -spin mixing matrix elements of 202,204 Hg are determined as well.
Unpolarized isovector quark distribution function from lattice QCD: A systematic analysis of renormalization and matching
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Nucleon isovector tensor charge from lattice QCD using chiral fermions
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Isovector parton distribution functions of the proton on a superfine lattice
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Strong coupling from an improved τ vector isovector spectral function
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Nucleon isovector scalar charge from overlap fermions
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Study of the decay D s + → K S 0 K S 0 π + and observation of an isovector partner to f 0 ( 1710 )
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Isovector and isoscalar tensor charges of the nucleon from lattice QCD
We present results for the iso-vector and flavor diagonal tensor charges $g$$^{u−d}_{T}$, $g$$^{u}_{T}$, $g$$^{d}_{T}$, and $g$$^{s}_{T}$ needed to probe novel tensor interactions at the TeV scale in neutron and nuclear β-decays and the contribution of the quark electric dipole moment (EDM) to the neutron EDM. The lattice QCD calculations were done using nine ensembles of gauge configurations generated by the MILC collaboration using the HISQ action with 2+1+1 dynamical flavors. These ensembles span three lattice spacings a ≈ 0.06, 0.09 and 0.12 fm and three quark masses corresponding to the pion masses M π ≈ 130, 220 and 310 MeV. Using estimates from these ensembles, we quantify all systematic uncertainties and perform a simultaneous extrapolation in the lattice spacing, volume and light quark masses for the connected contributions. The final estimates of the connected nucleon (proton) tensor charge for the iso-vector combination is $g$$^{u−d}_{T}$ = 1.020(76) in the MS scheme at 2 GeV. The additional disconnected quark loop contributions needed for the flavor-diagonal matrix elements are calculated using a stochastic estimator employing the truncated solver method with the all-mode-averaging technique. We find that the size of the disconnected contribution is smaller than the statistical error in the connected contribution. This allows us to bound the disconnected contribution and include it as an additional uncertainty in the flavor-diagonal charges. After a continuum extrapolation, we find $g$$^{u}_{T}$ = 0.774(66), $g$$^{d}_{T}$ = −0.233(28) and $g$$^{u+d}_{T}$ = 0.541(67). The strangeness tensor charge, that can make a significant contribution to the neutron EDM due to the large ratio ms/mu,d, is $g$$^{s}_{T}$ = 0.008(9) in the continuum limit.
Radiative and ρ transitions between a heavy quarkonium and isovector four-quark states
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Isovector charges of the nucleon from 2 + 1 + 1 -flavor lattice QCD
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Controlling excited-state contributions with distillation in lattice QCD calculations of nucleon isovector charges g S u − d , g A u − d , g T u − d
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Isovector EMC Effect from Global QCD Analysis with MARATHON Data
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Isovector and flavor diagonal charges of the nucleon from 2+1+1 flavor QCD
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Some nucleon isovector observables from 2+1-flavor domain-wall QCD at the physical pion mass
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Isovector and Isoscalar Charges of the Nucleon
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