Related papers: String breaking by light and strange quarks in QCD
We compute the static-light meson spectrum using two-flavor Wilson twisted mass lattice QCD. We have considered five different values for the light quark mass corresponding to 300 MeV < m_PS < 600 MeV. We have extrapolated our results, to…
The spectrum of gluon excitations in the presence of a static quark-antiquark pair is presented. Our results are obtained from computer simulations of gluons on anisotropic space-time lattices using an improved gauge-field action.…
We review the long term project of the ALPHA collaboration to compute in QCD the running coupling constant and quark masses at high energy scales in terms of low energy hadronic quantities. The adapted techniques required to numerically…
We report on the status of the analysis of the static energy in $2+1+1$-flavor QCD. The static energy is obtained by measuring Wilson line correlators in Coulomb gauge using the HISQ action, yielding the scales $r_{0}/a$, $r_{1}/a$,…
We analyze the large-distance behaviour of static quark-anti-quark pair correlations in QCD. The singlet free energy is calculated and the entropy contribution to it is identified allowing us to calculate the excess internal energy. The…
We report on our ongoing lattice QCD computation of antistatic-antistatic potentials in the presence of two light quarks using the CLS $N_f=2$ gauge configurations and the OpenQ*D codebase. We utilize a set of 16 creation operators,…
Cold nuclear matter effects in reactions with nuclei at a future electron-ion collider (EIC) lead to a modification of semi-inclusive hadron production, jet cross sections, and jet substructure when compared to the vacuum. At leading order…
For the case of two light flavors we propose the stringy description of the system made of one heavy and one light quark-antiquark pair, with the aim of exploring the two lower-lying Born-Oppenheimer potentials as a function of a separation…
A method in which electromagnetic properties of hadrons are studied by direct simulation of dynamical photon effects is applied to the extraction of the isomultiplet structure of the octet baryons. Using 187 configurations at $\beta=5.7$…
We determine the masses of the light and the strange quarks in the MS-bar-scheme using our high-statistics lattice simulation of QCD with dynamical Wilson fermions. For each of our three sea quarks we have analyzed our data at five…
We examine the spectrum of 2-colour lattice QCD with 4 continuum flavours at a finite chemical potential ($\mu$) for quark-number, on a $12^3 \times 24$ lattice. First we present evidence that the system undergoes a transition to a state…
We have studied the three quark systems in an Effective Hamiltonian approach in QCD. With only two parameters: the string tension sigma and the strong coupling constant alpha_s we obtain a good description of the ground state light and…
We assume that the u quarks and the d quarks constitute a body center cubic quark lattice in the vacuum. Using energy band theory, we deduce an excited quark spectrum (from the quark lattice). Using the accompanying excitation concept, we…
A distinct feature of Coulomb gauge QCD is that it can be formulated in terms of physical, transverse gluons and quarks alone. The state-counting is then transparent, and the gauge is suited for studies of the excited spectrum. Leaving…
We compute the low energy mass spectrum of lattice QCD in the large $N_C$ limit. Expanding around a gauge-invariant ground state, which spontaneously breaks the discrete chiral symmetry, we derive an improved strong-coupling expansion and…
We demonstrate a method for calculating the neutral B-meson decay constants and mixing matrix elements in unquenched lattice QCD with domain-wall light quarks and static b-quarks. Our computation is performed on the "2+1" flavor gauge…
Considered are ${\cal N}=2\, SU(N_c)$ or $U(N_c)$ SQCD with $N_F<2N_c-1$ quark flavors with the quark mass term $m{\rm Tr}\,({\bar Q} Q)$ in the superpotential. ${\cal N}=2$ supersymmetry is softly broken down to ${\cal N}=1$ by the mass…
Using first-principles calculation within Quantum Chromodynamics, we are able to determine a pattern of strangeness=1 resonances which appear as complex singularities within coupled $\pi K$, $\eta K$ scattering amplitudes. We make use of…
We report on spectra of circuit-quantum-electrodynamics (QED) systems in an intermediate regime that lies between the ultrastrong and deep-strong-coupling regimes, which have been reported previously in the literature. Our experimental…
Isospin symmetry is explicitly broken in the Standard Model by the non-zero differences of mass and electric charge between the up and down quarks. Both of these corrections are expected to have a comparable size of the order of one percent…