2,330 research outputs found
Finite temperature hadrons from holographic QCD
The properties of scalar mesons and glueballs at finite temperature are
analyzed through a {\it bottom-up} holographic approach. We focus on the
spectral functions and mass spectra. A discussion on hadron dissociation and
deconfinement phase transition is also put forward.Comment: 5 pages, 5 figures, talk given at "QCD@Work 2010 - International
Workshop on QCD - Theory and Experiment", June 20-23 2010, Martina Franca,
Ital
Gluon Condensate at finite temperature and density in holographic QCD
The lowest dimensional gluon condensate is analysed at finite
temperature and chemical potential using a bottom/up holographic model of QCD.
Starting from the free energy of the model, pressure, entropy and quark density
are obtained. Moreover, at zero chemical potential, the temporal and spatial
Wilson loops at low temperature are computed; they are related to the
(chromo-)electric and magnetic components of , respectively.Comment: 8 pages, 5 figures, Contribution to the conference QCD@Work 2014,
16-19 June 2014, Giovinazzo (Bari, Italy
In-medium effects on chiral condensate through holography
The behavior of chiral condensate in a hot and dense medium is investigated
within a phenomenological approach inspired by the AdS/CFT correspondence. We
find that it decreases when temperature and/or chemical potential are
increased, and it vanishes at some critical values. The locus of such critical
points is also drawn and discussed.Comment: Contribution to the conference QCD@Work - International Workshop on
QCD - Theory and Experiment, 18-21 June 2012, Lecce - Italy 5 pages, 3
figure
Properties of charmonia in a hot equilibrated medium
We investigate the properties of charmonia in a thermal medium, showing that
with increasing temperature the decay widths of these mesons behave in a
non-trivial way. Our analysis is based on a potential model with interaction
potential extracted from thermal lattice QCD calculations of the free-energy of
a static quark-antiquark pair. We find that in the crossover region some decay
widths are extremely enhanced, which might be interpreted as a signature of the
transition from hadronic matter to the deconfined phase. In particular, at
temperatures the decay widths of the that depend on the
value of the wave function at the origin are enhanced with respect to the
values in vacuum by about a factor 2. In the same temperature range the decay
width of the process is enhanced by
approximately a factor 6 with respect to the value in vacuum. At higher
temperatures the charmonia states dissociate and the widths of both decay
processes become vanishing small.Comment: minor changes, references added, almost matches published versio
Exotic mesons in a holographic model of QCD
Mesons with quantum numbers cannot be represented as simple
quark-antiquark pairs. We explore hybrid configurations in the light meson
sector comprising a quark, an antiquark and an excited gluon, studying the
properties of such states in a phenomenological model inspired by the
gauge/gravity correspondence. The computed mass, compared to the experimental
mass of the candidates , and ,
favous as the lightest hybrid state. An interesting result
concerns the stability of hybrid mesons at finite temperature: they disappear
from the spectral function (i.e. they melt) at a lower temperature with respect
to other states, light vector and scalar mesons, and scalar glueballs.Comment: 11 pages, 7 figure
Holographic Oddballs
The spectrum of the glueball with is computed using different
bottom-up holographic models of QCD. The results indicate a lowest-lying state
lighter than in the determination by other methods, with mass
GeV. The in-medium properties of this gluonium are investigated, and stability
against thermal and density effects is compared to other hadronic systems.
Production and decay modes are identified, useful for searching the
glueball.Comment: 16 pages, 9 figures, 3 table
- …