We analyze meson-baryon scattering lengths in the framework of covariant baryon chiral perturbation theory at leading one-loop order. We compute the complete set of matching relations between the dimension-two low-energy constants in the two- and three-flavor formulations of the theory. We derive new two-flavor low-energy theorems for pion-hyperon and pion-cascade scattering that can be tested in lattice simulations.
Short-range parts of the baryon-baryon ($BB$) interactions are analyzed from the spin-flavor $SU(6)_{sf}\supset SU(3)_f \times SU(2)_s$ symmetry viewpoint. Due to the Pauli principle of quarks, the symmetry structure of the wave functions is restricted at short distances. Consequently, the $BB$ states with the same spin-flavor quantum numbers may be reduced into one or a few spin-flavor states. Such reduction causes repulsion and/or suppression of transitions at short distances. We show that the observed suppression of the $ΞN \to ΛΛ$ conversion can be explained following the above argument. I…
Based on ideas that relate meson and baryon spectrum considering SUSY QM and light front holography, we propose a procedure to obtain LFWF for baryons starting from mesonic ones. We apply a procedure suggested for Gaussian ansatz used to study mesons.
We review heavy quark flavor and spin symmetries, their exploitation in heavy meson effective theories and the flavored couplings of charmed and light mesons in the definition of their effective Lagrangians. We point out how nonperturbative continuum QCD approaches based on Dyson-Schwinger and Bethe-Salpeter equations can be used to calculate strong and leptonic decays of open-charm mesons and heavy quarkonia. The strong decay $D^*\to Dπ$ serves as a benchmark, as it is the only physical open-charm observable that can be related to the effective Lagrangian's couplings. Nonetheless, a quantitat…
We proposed a unified framework to describe the interactions of the observed $T_{cc}$, $P_c$, and $P_{cs}$ within a quark level interaction in our previous work. In this work, we generalize our framework to the loosely bound hadronic molecules composed of heavy flavor di-hadrons with strangeness. We predict the possible $D^{(*)}D^{(*)}_s$ molecular states in the SU(3) limit with the masses of the $P_c$ states as the inputs. We also investigate the baryon-meson and baryon-baryon systems and consider the SU(3) breaking effect in their flavor wave functions. We generalize our isospin criterion of…
We present a comprehensive study of mass modifications of scalar, pseudo-scalar, vector, and axial-vector mesons in nuclear matter using the three-flavor extended Linear Sigma Model (eLSM) and the two-flavor Parity Doublet Model (PDM). The meson masses in nuclear matter are determined by calculating the one-loop nucleon corrections to the meson mean fields. As a result, we find all spin-$0$ meson masses except those of the pion, kaon, and the lightest scalar-isoscalar mesons decrease at finite baryon density. For spin-$1$ mesons, masses of all axial-vector mesons decrease in medium, and the de…
We present a new computation in a field-theoretical model of Coulomb gauge QCD of the first radial and angular excitations of a qqq system in a SU(3) flavor singlet state, Lambda_S. The traditional motivation for the study is that the absence of flavor singlets in the lowest-lying spectrum is a direct consequence of the color degree of freedom. (The calculation is tested with decuplet baryons Delta(1232) and Omega(1672).) We also analyze decay branching fractions of the flavor singlet baryon for various masses with the simplest effective Lagrangians.
We have developed a self-consistent theoretical approach to study the modification of the properties of heavy mesons in hot mesonic matter which takes into account chiral and heavy-quark spin-flavor symmetries. The heavy-light meson-meson unitarized scattering amplitudes in coupled channels incorporate thermal corrections by using the imaginary-time formalism, as well as the dressing of the heavy mesons with the self-energies. We report our results for the ground-state thermal spectral functions and the implications for the excited mesonic states generated dynamically in the heavy-light molecu…
We address the modification of open heavy-flavor mesons in a hot medium of light mesons within an effective theory approach consistent with chiral and heavy-quark spin-flavor symmetries and the use of the imaginary time formalism to introduce the non-zero temperature effects to the theory. The unitarized scattering amplitudes, the ground-state self-energies and the corresponding spectral functions are calculated self-consistently. We use the thermal ground-state spectral functions obtained with this methodology to further calculate 1) open-charm meson Euclidean correlators, and 2) off-shell tr…
A meson-baryon interaction in the charm $+1$, strangeness $-2$ and isospin $0$ sector is built from a t-channel vector meson exchange model employing effective Lagrangians. The implementation of coupled-channel unitarization in the s-wave scattering amplitudes gives rise to two structures that have similar masses and widths to those of the $Ω_c(3050)^0$ and $Ω_c(3090)^0$ states recently observed by the LHCb collaboration. A meson-baryon molecular interpretation of these resonances would assign their spin-parity to be $J^P=1/2^-$.
Integral equations for meson-baryon scattering amplitudes are obtained by utilizing time-ordered perturbation theory for a manifestly Lorentz-invariant formulation of baryon chiral perturbation theory. Effective potentials are defined as sums of two-particle irreducible contributions of time-ordered diagrams and the scattering amplitudes are obtained as solutions of integral equations. Ultraviolet renormalizability is achieved by solving integral equations for the leading order amplitude and including higher order corrections perturbatively. As an application of the developed formalism, pion-n…
