Related papers: I=2 Pion Scattering Phase Shift with Wilson Fermio…
We present a calculation of the phase-shift for $\pi$-$\pi$ scattering in isospin-1, spin-1 channel in the elastic region. The mass and width of the rho resonance is extracted by fitting these phaseshifts. To vary the scattering momentum we…
We perform a nonperturbative lattice calculation of the complex phase and modulus of the pion form factor in the timelike momentum region using the finite-volume technique. We use two ensembles of 2+1-flavor overlap fermion at pion masses…
We calculate the parameters describing elastic $I=1$, $P$-wave $\pi\pi$ scattering using lattice QCD with $2+1$ flavors of clover fermions. Our calculation is performed with a pion mass of $m_\pi \approx 320\:\:{\rm MeV}$ and a lattice size…
L\"uscher has suggested a method to determine phase shifts from the finite volume dependence of the two-particle energy spectrum. We apply this to two models in d=2: (a) the Ising model, (b) a system of two Ising fields with different mass…
Using lattice QCD we extract $\pi\pi$ scattering amplitudes with isospin--0,1,2 in low partial-waves at two values of the light quark mass corresponding to $m_\pi \sim 283$ and $330$ MeV. We confirm expectations of weak repulsion in…
We study the coupled pion-nucleon system (negative parity, isospin 1/2) based on a lattice QCD simulation for nf=2 mass degenerate light quarks. Both, standard 3-quarks baryon operators as well as meson-baryon (4+1)-quark operators are…
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…
Lattice QCD calculations using gauge smearing for fermion kernels are computationally efficient. Hypercubic blocking (nHYP smearing) has been shown to reduce scaling errors. In this work we use an improved action for $N_f=2$ QCD, based on…
We use 2HEX smeared gauge configurations generated with an $\mathrm{N}_\mathrm{f}\mathrm{=2+1}$ clover improved Wilson action to investigate $\pi\pi$ scattering in the $\rho$ channel. The range of lattice spacings (0.054 to 0.12 fm) and…
In this investigation, we examine how the precision of energy spectra and scattering phase shifts, extracted in lattice QCD, depend upon the degree of distillation type smearing. We use the variational method to extract energy spectra for…
We calculate the electromagnetic pion form factor in lattice QCD with 2+1 flavors of the dynamical overlap quarks. Up and down quark masses are set below their physical values so that the system is in the so-called epsilon regime with the…
Nucleon-nucleon systems in the $^3S_1$ and the $^1S_0$ channels are studied in lattice quantum chromodynamics at a pion mass of approximately $m_{\pi}\approx292$ MeV, employing three $N_f = 2+1$ ensembles with the same pion mass and lattice…
We present our result for the $K\to\pi\pi$ decay amplitudes for both the $\Delta I=1/2$ and $3/2$ processes with the improved Wilson fermion action. Expanding on the earlier works by Bernard {\it et al.} and by Donini {\it et al.}, we show…
We study QCD with two flavors of dynamical Wilson fermions at $\beta = 5.5$ and three values of $\kappa$. The corresponding pion masses are 0.375, 0.324 and 0.262 in lattice units, with pion to rho mass ratios of 0.76, 0.71 and 0.62,…
Lattice QCD calculations of radiative transitions between hadrons have in the past been limited to processes of hadrons stable under the strong interaction. Recently developed methods for $1\to2$ transition matrix elements in a finite…
We study the possibility that the scalar mesons exist as four-quark states. The energy shift of two pseudoscalar mesons as a function of spatial lattice size makes a distinction between bound states and scattering states of four-quark…
Using Nf=2+1+1 lattice QCD, we determine the fermionic connected contributions to the second and third moment of the pion PDF. Based on gauge configurations from the European Twisted Mass Collaboration, chiral and continuum extrapolations…
We study the scaling properties of the finite temperature QCD phase transition, for light quark masses ranging from the heavy quark regime to their physical values. The lattice results are obtained in the fixed scale approach from…
We investigate the thermal QCD phase transition and its scaling properties on the lattice. The simulations are performed with $N_f=2+1+1$ Wilson twisted mass fermions at pion masses from physical up to heavy quark regime. We introduce a…
The I=2 pipi scattering length is calculated in fully-dynamical lattice QCD with domain-wall valence quarks on the asqtad-improved coarse MILC configurations (with fourth-rooted staggered sea quarks) at four light-quark masses. Two- and…