We describe how the inclusion of gluonic Polyakov loop incorporates large gauge invariance and drastically modifies finite temperature calculations in chiral quark models after color neutral states are singled out. This generates an effective theory quarks loops as basic degrees freedom. find a strong suppression effects hadronic observables triggered by approximate triality conservation (Polyakov cooling), so that while center symmetry breaking is exponentially small with constituent mass,...

We study charmed baryon resonances that are generated dynamically within a unitary meson-baryon coupled-channel model treats the heavy pseudoscalar and vector mesons on equal footing as required by heavy-quark symmetry. It is an extension of recent SU(4) models with $t$-channel vector-meson exchanges to SU(8) spin-flavor scheme, but differs considerably from approach in how strong breaking flavor symmetry implemented. Some our states can be readily assigned recently observed resonances,...

We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished extending the SU(3) Weinberg-Tomozawa chiral Lagrangian to SU(8) spin-flavor symmetry plus suitable breaking. The produces with negative parity from s-wave interaction of pseudoscalar vector mesons $1/2^+$ $3/2^+$ baryons. Resonances in all isospin, spin, sectors one, two, three charm units studied....

A model is developed to describe odd-parity baryon resonances generated dynamically through a unitary baryon-meson coupled-channels approach. The scheme applies channels with light- and/or heavy-quark content. Distinct features of the are that i) interaction an $S$-wave contact one, ii) it reduces SU(3) Weinberg-Tomozawa Hamiltonian when light pseudoscalar mesons involved, thus respecting chiral symmetry, iii) spin-flavor preserved in light-quark sector, and iv) spin symmetry fulfilled...

The LHCb Collaboration has recently observed two narrow baryon resonances with beauty. Their masses and decay modes look consistent the quark model orbitally excited states Lambda_b(5912) Lambda*_b(5920), quantum numbers J^P=1/2^- 3/2^-, respectively. We predict existence of these within a unitarized meson-baryon coupled-channel dynamical model, which implements heavy-quark spin symmetry. Masses, couplings to different channels are obtained. find that Lambda^0_b(5912) Lambda^0_b(5920)...

We use a consistent SU(6) extension of the meson-baryon chiral Lagrangian within coupled channel unitary approach in order to calculate $T$ matrix for scattering $s$ wave. The building blocks scheme are $\ensuremath{\pi}$ and $N$ octets, $\ensuremath{\rho}$ nonet $\ensuremath{\Delta}$ decuplet. identify poles this interpret them as resonances. study here nonexotic sectors with strangeness $S=0$, $\ensuremath{-}1$, $\ensuremath{-}2$, $\ensuremath{-}3$ spin $J=\frac{1}{2}$, $\frac{3}{2}$...

The dynamics of systems composed a classical sector plus quantum is studied. We show that, even in the simplest cases, (i) existence consistent canonical description for such mixed incompatible with very basic requirements related to time evolution two sectors when they are decoupled, (ii) cannot inherit fluctuations from sector, and (iii) coupling among requirement physical positivity theory, i.e., there would be positive observables nonpositive expectation value.

Following a model based on the SU(8) symmetry that treats heavy pseudoscalars and vector mesons an equal footing, as required by quark symmetry, we study interaction of baryons in coupled channels within unitary approach generates dynamically poles scattering $T$-matrix. We concentrate exotic with negative charm quantum number for which there is experimental claim one state.

We reanalyze the decay mode of \ensuremath{\Lambda} hypernuclei induced by two nucleons modifying previous numerical results and interpretation process. The repercussions this channel in ratio neutron to proton is studied detail connection with present experimental data. This leads ratios that are greater contradiction usual one pion exchange models than those deduced before.

A consistent SU(6) extension of the Weinberg-Tomozawa meson-baryon chiral Lagrangian is constructed which incorporates vector meson and baryon decuplet degrees freedom. The corresponding Bethe-Salpeter approximation predicts existence an isoscalar spin-parity ${3/2}^-$ $K^*N$ bound state (strangeness +1) with a mass around 1.7--1.8$ $GeV. It highest hypercharge antidecuplet SU(3) representation it unstable through $K^*$ decay. estimated width this (neglecting d-wave $KN$ decay) turns out to...

The anti-D meson self-energy is evaluated self-consistently, using unitarized coupled-channel theory, by computing the in-medium meson-baryon T-matrix in C=-1,S=0 sector. heavy pseudo-scalar and vector mesons, anti-D^*, are treated on equal footing as required quark spin symmetry. Results for energy levels widths of D^- mesic atoms 12C, 40Ca, 118Sn 208Pb presented. spectrum contains states atomic nuclear types all nuclei. anti-D^0--nucleus bound also obtained. We find that, after...

The Polyakov loop has been used repeatedly as an order parameter in the deconfinement phase transition QCD. We argue that, confined phase, its expectation value can be represented terms of hadronic states, similarly to hadron resonance gas model for pressure. Specifically, $L(T)\ensuremath{\approx}\frac{1}{2}\ensuremath{\sum}_{\ensuremath{\alpha}}{g}_{\ensuremath{\alpha}}{e}^{\ensuremath{-}{\ensuremath{\Delta}}_{\ensuremath{\alpha}}/T}$, where ${g}_{\ensuremath{\alpha}}$ are degeneracies and...

We study the dependence on quark mass of compositeness lowest-lying odd parity hyperon states. Thus, we pay attention to $\mathrm{\ensuremath{\Lambda}}$-like states in strange, charm, and beauty sectors which are dynamically generated using a unitarized meson-baryon model. In strange sector use SU(6) extension Weinberg-Tomozawa interaction, further implement heavy-quark spin symmetry construct interaction when charmed or hadrons involved. three examined flavor sectors, obtain two...

We investigate whether the stationary solution of Fokker-Planck equation complex Langevin algorithm reproduces correct expectation values. When for an action $S(x)$ is convergent, it produces equivalent probability distribution $P(x)$ which ideally would coincide with $e^{-S(x)}$. show that projected fulfilled by may contain anomalous term whose form made explicit. Such spoils relation $P(x)=e^{-S(x)}$, introducing a bias in Through analysis several periodic and non-periodic one-dimensional...

We analyze the consequences of inclusion gluonic Polyakov loop in chiral quark models at low temperature light perturbation theory. Specifically, low-energy effective Lagrangian from two such is computed. The tree level vacuum energy density, condensate, pion decay constant, and Gasser-Leutwyler coefficients are found to acquire a dependence. This dependence is, however, exponentially small for temperatures below mass gap full unquenched calculation. introduction its quantum fluctuations...

We present a new formal approach for the calculation of s-wave optical potential pionic atoms which makes extensive use Lindhard function, its analytical properties, and useful low density limit. The conventional parameters ${b}_{0}$ ${B}_{0}$ are calculated compared to results from empirical fits atom data. show that virtual excitation ph-\ensuremath{\Delta}h components by pion is main source real part ${B}_{0}$. Higher order effects polarization lead some enhancement Im${B}_{0}$, providing...

A recently proposed phenomenological model, which includes nonperturbative effects from dimension two gluon condensates, is applied to analyze the available lattice data for heavy quark free energy in deconfined phase of quenched QCD. For large $q\bar{q}$ separations, we recover previous results Polyakov loop, exhibiting unequivocal power corrections temperature. potential at finite temperature and separation, find that a good overall description can be achieved once condensate properly...