Related papers: Chiral multiplets versus parity doublets in highly…
The chirally symmetric baryon parity-doublet model can be used as an effective description of the baryon-like objects in the chirally symmetric phase of QCD. Recently it has been found that above the critical temperature higher chiralspin…
We find remarkable agreement with the observed excitations of hadrons with a simple three parameter mass relation of the SU(3) subgroup of the underlying U(15/30) graded Lie group. The baryons are the appropriate supersymmetric partners of…
At zero temperature the negative-parity ground states of the nucleon and delta baryons are non-degenerate with the positive-parity partners due to spontaneous breaking of chiral symmetry. However, chiral symmetry is expected to be restored…
We study the conjectured "Insensitivity to Chiral Symmetry Breaking" in the highly excited light baryon spectrum. While the experimental spectrum is being measured at JLab and CBELSA/TAPS, this insensitivity remains to be computed…
The lower excitation spectrum of the nucleon and $\Delta$ is calculated in a relativistic chiral quark model. Contributions of the second order self-energy and exchange diagrams due-to pion fields to the mass spectrum of the SU(2) baryons…
We investigate the properties of dense matter and neutron stars. In particular we discuss model calculations based on the parity doublet picture of hadronic chiral symmetry. In this ansatz the onset of chiral symmetry restoration is…
The recently postulated existence of a baryon antidecuplet [1] can be reproduced in strong coupling theory in which a bare baryon spin 1/2 octet interacts with an octet of pseudoscalar mesons. When a suitable mixture of F- and D-type Yukawa…
The spectrum of the SU(2) flavor baryons is studied in the frame of a relativistic chiral quark potential model based on the one-pion and one-gluon exchange mechanisms. It is argued that the N* and Delta* resonances strongly coupled to the…
There are numerous examples of approximately degenerate states of opposite parity in molecular physics. Theory indicates that these doubles can occur in molecules that are reflection-asymmetric. Such parity doubles occur in nuclear physics…
Baryon resonances with even and odd parity are collectively investigated from the viewpoint of chiral symmetry(ChS). We propose a quartet scheme where Delta's and N^*'s with even and odd parity form a chiral multiplet. This scheme gives…
A chiral model is introduced that is based on the parity doublet formulation of chiral symmetry including hyperonic degrees of freedom. The phase structure of the model is determined. Depending on the masses of the chiral partners the…
Chiral symmetry in QCD can be simultaneously in Wigner and Goldstone modes, depending on the part of the spectrum examined. The transition regime between both, exploiting for example the onset of parity doubling in the high baryon spectrum,…
We propose novel superfluids induced by the parity-doubled baryons. The parity-doubled baryons, i.e., a nucleon $N(940)$ with spin-parity $J^{P}=1/2^{+}$ and an excited nucleon $N^{\ast}(1535)$ with $J^{P}=1/2^{-}$ in vacuum, become…
The Nucleon- and the Lambda-excitation spectrum exhibit parity doublets, i.e. states of the same spin but with opposite parity being almost degenerate in mass. It is shown that in a relativistic quark model with instantaneous interaction…
Chiral-parity (parity-doublet) effective Lagrangian models provide a compact and symmetry-consistent framework for describing baryons and their negative-parity partners in terms of linearly-realized chiral symmetry. Unlike the conventional,…
Recent lattice QCD studies at vanishing density exhibit the parity-doubling structure for the low-lying baryons around the chiral crossover temperature. This finding is likely an imprint of the chiral symmetry restoration in the baryonic…
Recent data for highly excited mesons suggest that not only the chiral $SU(2)_L\times SU(2)_R$ symmetry of QCD is restored high in the spectrum but also the $ U(1)_A$ symmetry. This means that it is not a confining interaction in QCD which…
We construct the most general nonlinear representation of chiral SU(2)_L x SU(2)_R broken down spontaneously to the isospin SU(2), on a pair of hadrons of same spin and isospin and opposite parity. We show that any such representation is…
We study the possible existence of chiral partners in the spin-$\thalf$ sector of the baryon spectrum. We consider a quartet scheme where four spin-3/2 baryons, $P_{33}$, $D_{33}$, $D_{13}$ and $P_{13}$, group into higher-dimensional chiral…
These lectures discuss the question of whether a key feature is seen in hadron spectroscopy--the near degeneracy of hadrons with different parity and/or spin. It has been conjectured that this is due to an effective restoration of chiral…