Related papers: Disconnected Loops with Twisted Mass Lattice QCD
We review two lattice calculations involving charm hadrons: a determination of the vector and scalar form factors of the semileptonic $D \to \pi \ell \nu$ decays, which are relevant for the extraction of the CKM matrix element $\lvert…
I review recent theoretical developments and numerical results of twisted mass QCD. I argue that, combined with an efficient algorithm, twisted mass QCD can be an attractive QCD lattice action, to perform large scale simulations at small…
A method for computing electromagnetic properties of hadrons in lattice QCD is described and preliminary numerical results are presented. The electromagnetic field is introduced dynamically, using a noncompact formulation. Employing…
We propose improved estimators to compute the reweighting factors which are needed for lattice QCD calculations that rely on twisted-mass reweighting for the light quark contribution and the Rational Hybrid Monte Carlo (RHMC) algorithm for…
We apply twisted boundary conditions to lattice QCD simulations of three-point correlation functions in order to access spatial components of hadronic momenta different from the integer multiples of 2 pi / L. We calculate the vector and…
We present a comprehensive investigation of light meson physics using maximally twisted mass fermions for two mass-degenerate quark flavours. By employing four values of the lattice spacing, spatial lattice extents ranging from 2.0 fm to…
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…
Calculations of neutrino-nucleus cross sections begin with the neutrino-nucleon interaction, making the latter critically important to flagship neutrino oscillation experiments, despite limited measurements with poor statistics.…
The strangeness contribution to the electric and magnetic properties of the nucleon has been under investigation experimentally for many years. Lattice Quantum Chromodynamics (LQCD) gives theoretical predictions of these measurements by…
In the past year, we calculated with lattice QCD three quantities that were unknown or poorly known. They are the $q^2$ dependence of the form factor in semileptonic $D\to Kl\nu$ decay, the decay constant of the $D$ meson, and the mass of…
We present a lattice calculation of the vector form factor of the pion for two flavours of non-perturbatively O(a) improved Wilson fermions. For the measurements we utilise the CLS ensembles which include various lattice spacings and pion…
We review the current status of lattice QCD studies of the nucleon system. In particular, we focus on the determination of the shape of the nucleon by probing its wave function as well as by evaluating the N to Delta transition form…
We present a calculation of $< x >_s$ for the strange quark in the nucleon. We also report the ratio of the strange $< x >$ to that of $u/d$ in the disconnected insertion which will be useful in constraining the global fit of parton…
Using noise methods on a quenched $20^3 \times 32$ lattice at $\beta=6.0$, we have investigated vacuum expectation values and relative linear correlations among the various Wilson and twisted mass scalar and pseudoscalar disconnected loop…
Two twisted doublets, one containing the up and down quarks and the other containing the strange quark with an SU(2)-flavor partner, are used for studies in the meson sector. The relevant chiral perturbation theory is presented, and…
We present a calculation of cut-off effects at tree-level of perturbation theory for the K and D mesons using the twisted mass formulation of lattice QCD. The analytical calculations are performed in the time-momentum frame. The relative…
We present a scaling study of lattice QCD with O(a) improved Wilson fermions and a chirally twisted mass term. In order to get precise results with a moderate computational effort, we have considered a system of physical size of 0.75^3 *…
We present preliminary results for the charm quark mass $m_c$ and the $D$ and $D_s$ mesons decay constants $f_D$ and $f_{D_s}$ from a lattice QCD calculation with ${\rm N_f}$ = 2 dynamical fermions. We use the twisted mass fermionic action…
Method of calculating hadron multi-point functions and disconnected quark loop contributions which are not readily accessible through conventional techniques is proposed. Results are reported for pion-pion, pion-nucleon and nucleon-nucleon…
We present physics results from simulations of QCD using $N_f = 2$ dynamical Wilson twisted mass fermions at the physical value of the pion mass. These simulations were enabled by the addition of the clover term to the twisted mass quark…