Related papers: Determining Sigma - Lambda mixing
The SELEX Collaboration has reported a very large isospin splitting of doubly charmed baryons. We show that this effect would imply that the doubly charmed baryons are very compact. One intriguing possibility is that such baryons have a…
Hadron masses are computed from quenched twisted mass lattice QCD for a degenerate doublet of up and down quarks with the twist angle set to pi/2, since this maximally twisted theory is expected to be free of linear discretization errors.…
Meson properties are considered within a U(3)\times U(3) Linear Sigma Model(LSM). The importance of the U_A(1)-breaking term and the OZI rule violating term in the generation of meson masses and mixing angles is stressed. The LSM parameters…
Various suggestions exist for incorporating the strange quark into twisted mass QCD. One option for quenched simulations is to employ two twisted doublets, (u,d) and (c,s), with separate twist angles. Working in the isospin limit,…
We study decuplet baryons from meson-baryon interactions, in particular, $\Delta$ and $\Omega$ baryons from P-wave $I=3/2$ $N\pi$ and $I=0$ $\Xi\bar{K}$ interactions, respectively. The interaction potentials are calculated in the HAL QCD…
We consider the mass splittings and strong decays of members of the lowest-lying pentaquark multiplet, which we take to be a parity-odd antidecuplet. We derive useful decompositions of the quark model wave functions that allow for easy…
The mass spectrum of heavy quark baryons has been computed on anisotropic lattices using quenched lattice nonrelativistic QCD. The mass splittings between spin-1/2 and spin-3/2 baryons are also calculated. Results are compared to those…
Isospin-breaking corrections pose a significant challenge to lattice simulations, both because of the splitting between the up and down quark masses and, in particular, the need to include QED effects. The RC* collaboration has developed…
We study baryons on the lattice with a special focus on excited states. For that purpose we construct several interpolators which differ in their Dirac structure. These interpolators are built from Jacobi smeared quarks with different…
We present an exploratory study of leading isospin breaking effects in mesonic masses using $O(a)$ improved Wilson fermions. Isospin symmetry is explicitly broken by distinct masses and electric charges of the up and down quarks. In order…
Lattice quantum chromodynamics is used to constrain the interactions of two octet baryons at the SU(3) flavor-symmetric point, with quark masses that are heavier than those in nature (equal to that of the physical strange quark mass and…
We compute the electromagnetic mass difference for the $B$-, $D$- and $K$-mesons using QCD sum rules with double dispersion relations. For the $B$- and $D$-mesons we also compute the linear quark mass correction, whereas for the $K$ the…
Masses of baryons {3/2}^+ are calculated on the base of representations of dynamical "pseudounitary" q-deformed algebra u(4,1)_q which provides necessary breaking of the 4-flavor symmetry realized by the assumed q-algebra su(4)_q. It is…
The spectrum and dominant strong decay properties of the doubly heavy baryons are revisited by using a chiral effective model with chiral partner structure. By regarding the doubly heavy baryons in the ground states and light angular…
We use the method of QCD sum rules to investigate the isospin symmetry breaking of K and K* mesons. The electromagnetic effect, difference between up and down current-quark masses and difference between up and down quark condensates are…
We compute the static-light baryon spectrum by means of Wilson twisted mass lattice QCD using N_f = 2 flavors of sea quarks. As light u/d valence quarks we consider quarks, which have the same mass as the sea quarks with corresponding pion…
The spectroscopy of the doubly heavy baryons including different heavy quarks is studied based on the heavy quark symmetry of QCD. We point out that, when the two heavy quarks are in $S$-wave, these baryons with a certain spin $j_l$ of the…
We study $S$-wave interactions of the baryon decuplet with the octet of pseudoscalar mesons using the lowest order chiral Lagrangian. We find two bound states in the SU(3) limit corresponding to the octet and decuplet representations. These…
By comparing SU(3)-breaking scales of linear mass formulae, it is shown that the lowest vector, axial-vector, and scalar mesons all have a $\bar{q}q$ configuration, while the ground-state octet and decuplet baryons are $qqq$. Also, the…
We discuss systematically the fermion mass and mixing matrices in a generic \linebreak field-theoretical flipped $SU(5)$ model, with particular applications to neutrino and baryon number-changing physics. We demonstrate that the different…