相关论文: Flavor-Spin Symmetry and the Tensor Charge
Exploiting an approximate phenomenological symmetry of the $J^{PC}=1^{+-}$ light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge. The result depends on the decay constants of…
Exploiting the phenomenological symmetry of the $J^{PC}=1^{+-}$ light axial vector mesons and using pole dominance, we calculate the flavor contributions to the nucleon tensor charge.
The axial vector and tensor charge, defined as the first moments of the forward nucleon matrix elements of corresponding quark currents, are essential for characterizing the spin structure of the nucleon. However, the transversity…
The flavor singlet axial and tensor charges of the nucleon are calculated in lattice QCD. We find $\Delta\Sigma=\Delta u+\Delta d+\Delta s=+0.638(54)-0.347(46)-0.109(30) = +0.18(10)$ for the axial charge and $\delta\Sigma=\delta u+\delta…
Like the axial vector charges, defined from the forward nucleon matrix element of the axial vector current on the light cone, the nucleon tensor charge, defined from the corresponding matrix element of the tensor current, is essential for…
Tensor charge of the nucleon, which will be measured in Drell-Yan processes in polarized proton-proton collisions at RHIC, are studied in quenched lattice QCD simulation. On the 16$^3\times$ 20 lattice with $\beta=5.7$, connected parts of…
We present results for the isovector axial, scalar and tensor charges $g^{u-d}_A$, $g^{u-d}_S$ and $g^{u-d}_T$ of the nucleon needed to probe the Standard Model and novel physics. The axial charge is a fundamental parameter describing the…
We determine the nucleon axial, scalar and tensor charges at the continuum limit by analyzing three $N_f=2+1+1$ twisted mass fermion ensembles with all quark masses tuned to approximately their physical values. We include all contributions…
We present state-of-the-art results for the matrix elements of flavor diagonal tensor operators within the nucleon state. The calculation of the dominant connected contribution is done using eleven ensembles of gauge configurations…
We determine the nucleon axial, scalar and tensor charges within lattice Quantum Chromodynamics including all contributions from valence and sea quarks. We analyze three gauge ensembles simulated within the twisted mass formulation at…
We present an update of our analysis of statistical and systematic errors in the calculation of iso-vector scalar, axial and tensor charges of the nucleon. The calculations are done using $N_f=2+1+1$ flavor HISQ ensembles generated by the…
We present high-statistics results for the isovector and flavor diagonal charges of the proton using 11 ensembles of 2+1+1 flavor HISQ fermions. In the isospin symmetric limit, results for the neutron are given by the $u \leftrightarrow d$…
The three flavor soliton approach for baryons is utilized to discuss effects of flavor symmetry breaking in the baryon wave--functions on axial current matrix elements. The flavor content of the singlet axial current matrix elements, that…
This talk provides an update on the calculation of matrix elements of flavor diagonal axial, scalar and tensor quark bilinear operators between the nucleon ground state. The simulations are done using Wilson-clover fermions on a sea of…
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 $\beta$-decays and the contribution…
We determine the nucleon axial, scalar and tensor charges and the nucleon $\sigma$-terms using twisted mass fermions. We employ three ensembles with approximately equal physical volume of about 5.5~fm, three values of the lattice spacing,…
This talk provides an update on the calculation of matrix elements of flavor diagonal axial, scalar and tensor quark bilinear operators between the nucleon ground state. The simulations are done using Wilson-clover fermions on a sea of…
We study the mass spectrum of light pseudoscalar and vector mesons in the presence of an external uniform magnetic field $\vec B$, considering the effects of the mixing with the axial vector meson sector. The analysis is performed within a…
We investigate the internal structure of a comprehensive set of pseudoscalar and vector mesons, including both flavor-symmetric and flavor-asymmetric systems, by reconstructing their charge distributions from electromagnetic form factors.…
We present preliminary results for the axial and tensor charge of the nucleon obtained from simulations with N_f=2 clover fermions. A comparison with chiral perturbation theory is attempted.