13,662 research outputs found
Infrared-Improved Soft-wall AdS/QCD Model for Mesons
We construct and investigate an infrared-improved soft-wall AdS/QCD model for
mesons. Both linear confinement and chiral symmetry breaking of low energy QCD
are well characterized in such an infrared-improved soft-wall AdS/QCD model.
The model enables us to obtain a more consistent numerical prediction for the
mass spectra of resonance scalar, pseudoscalar, vector and axial-vector mesons.
In particular, the predicted mass for the lightest ground state scalar meson
shows a good agreement with the experimental data. The model also provides a
remarkable check for the Gell-Mann-Oakes-Renner relation and a sensible result
for the space-like pion form factor.Comment: 15 pages, 4 figures, 7 tables, published versio
Critical behaviors near the (tri-)critical end point of QCD within the NJL model
We investigate the dynamical chiral symmetry breaking and its restoration at
finite density and temperature within the two-flavor Nambu-Jona-Lasinio model,
and mainly focus on the critical behaviors near the critical end point (CEP)
and tricritical point (TCP) of quantum chromodynamics. The multi-solution
region of the Nambu and Wigner ones is determined in the phase diagram for the
massive and massless current quark, respectively. We use the various
susceptibilities to locate the CEP/TCP and then extract the critical exponents
near them. Our calculations reveal that the various susceptibilities share the
same critical behaviors for the physical current quark mass, while they show
different features in the chiral limit
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