Related papers: Disconnected Electromagnetic Form Factors
We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical…
We give a general introduction and discussion of the issues involved in using the twisted mass formulation of lattice fermions in the context of disconnected loop calculations, including a short orientation on the present experimental…
A new calculation of the neutron electric form factor is described. Preliminary results for the connected part on a $20^{3}\times 32$ lattice are presented. The methods for calculating the disconnected part are briefly described.
We report on lattice results of the form factors for semi-leptonic decays of the D_s meson to eta and eta', with n_f=2+1 configurations. The calculation contains disconnected fermion loop diagrams, which are challenging to calculate on the…
We present results for the nucleon electromagnetic form factors using an ensemble of maximally twisted mass clover-improved fermions with pion mass of about 130 MeV. We use multiple sink-source separations and three analysis methods to…
We perform a high statistics calculation of disconnected fermion loops on Graphics Processing Units for a range of nucleon matrix elements extracted using lattice QCD. The isoscalar electromagnetic and axial vector form factors, the…
We present results for the isoscalar electromagnetic form factors of the nucleon computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_\mathrm{f} = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an…
We report lattice results of $D_s$ meson semi-leptonic decay form factors to $\eta$ and $\eta'$ mesons. This decay process contains disconnected fermion loops, which are challenging in lattice calculations. Our result shows that the…
We compute the electromagnetic form factors of the nucleon in quenched lattice QCD, using non-perturbatively improved Wilson fermions, and compare the results with phenomenology and chiral effective field theory.
The electromagnetic form factors of the proton and the neutron are computed within lattice QCD using simulations with quarks masses fixed to their physical values. Both connected and disconnected contributions are computed. We analyze two…
We present results for the electromagnetic form factors of the proton and neutron computed on the Coordinated Lattice Simulations (CLS) ensembles with $N_f = 2 + 1$ flavors of $\mathcal{O}(a)$-improved Wilson fermions and an…
We present results on the nucleon electromagnetic form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length L=2.1 fm and L=2.8 fm.…
We calculate electric and magnetic form factors of protons and neutrons in quenched Monte Carlo lattice QCD on a $16^3\times 24$ lattice at $\beta = 6.0$ using Wilson fermions. We employ a method which characterizes one of the nucleon…
We calculate for the first time the form factors of the semi-leptonic decays of the $D_s$ meson to $\eta$ and $\eta^\prime$ using lattice techniques. As a by-product of the calculation we obtain the masses and leading distribution…
We report a direct lattice QCD calculation of the strange nucleon electromagnetic form factors $G_E^s$ and $G_M^s$ in the kinematic range $0 \leq Q^2 \lesssim 1.2\: {\rm GeV}^2$. For the first time, both $G_E^s$ and $G_M^s$ are shown to be…
The electromagnetic form factors provide important insight into the internal structure of the nucleon and continue to be of major interest for experiment and phenomenology. For an intermediate range of momenta the form factors can be…
We present the nucleon strange electromagnetic form factors using four lattice QCD ensembles with $N_f=2+1+1$ twisted mass clover-improved fermions and quark masses tuned to approximately their physical values. The four ensembles have…
Recent progress in lattice QCD calculations of nucleon structure will be presented. Calculations of nucleon matrix elements and form factors have long been difficult to reconcile with experiment, but with advances in both methodology and…
We analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF) $F_3$ and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor $F_2$ due to inadequate…
Elastic electromagnetic form factors of nucleons are investigated both for the time-like and the space-like momentums by using the unsubtracted dispersion relation with QCD constraints. It is shown that the calculated form factors reproduce…