6 research outputs found
Quark Gluon Bags as Reggeons
The influence of the medium dependent finite width of QGP bags on their
equation of state is analyzed within an exactly solvable model. It is argued
that the large width of the QGP bags not only explains the observed deficit in
the number of hadronic resonances, but also clarifies the reason why the heavy
QGP bags cannot be directly observed as metastable states in a hadronic phase.
The model allows us to estimate the minimal value of the width of QGP bags from
a variety of the lattice QCD data and get that the minimal resonance width at
zero temperature is about 600 MeV, whereas the minimal resonance width at the
Hagedorn temperature is about 2000 MeV. As shown these estimates are almost
insensitive to the number of the elementary degrees of freedom. The recent
lattice QCD data are analyzed and it is found that besides sigma T**4 term the
lattice QCD pressure contains T-linear and T**4 ln T terms in the range of
temperatures between 240 MeV and 420 MeV. The presence of the last term in the
pressure bears almost no effect on the width estimates. Our analysis shows that
at hight temperatures the average mass and width of the QGP bags behave in
accordance with the upper bound of the Regge trajectory asymptotics (the linear
asymptotics), whereas at low temperatures they obey the lower bound of the
Regge trajectory asymptotics (the square root one). Since the model explicitly
contains the Hagedorn mass spectrum, it allows us to remove an existing
contradiction between the finite number of hadronic Regge families and the
Hagedorn idea of the exponentially growing mass spectrum of hadronic bags.Comment: One section removed, a few references added, the Regge trajectories
of free QGP bags are considere
Nonlinear Regge trajectories and glueballs
We apply a phenomenological approach based on nonlinear Regge trajectories to
glueball states. The parameters, i.e., intercept and threshold, or trajectory
termination point beyond which no bound states should exist, are determined
from pomeron (scattering) data. Systematic errors inherent to the approach are
discussed. We then predict masses of glueballs on the tensor trajectory. For
comparison, the approach is applied to available quenched lattice data. We find
a discrepancy between the lattice based thresholds and the pomeron threshold
that we extract from data.Comment: 15pp., revtex4, 2 fig
Asymptotic Regge Trajectories of Non-strange Mesons
We analyze the asymptotic behavior of Regge trajectories of non-strange
mesons. In contrast to an existing belief, it is demonstrated that for the
asymptotically linear Regge trajectories the width of heavy hadrons cannot
linearly depend on their mass. Using the data on masses and widths of rho_J,
omega_J, a_J and f_J mesons for the spin values J \leq 6, we extract the
parameters of the asymptotically linear Regge trajectory predicted by the
finite width model of quark gluon bags. As it is shown the obtained parameters
for the data set B correspond to the cross-over temperature lying in the
interval 170.9-175.3 MeV which is consistent with the kinetic freeze-out
temperature of early hadronizing particles found in relativistic heavy ion
collisions at and above the highest SPS energy.Comment: 14 pages, 3 figure
Effective Functional Form of Regge Trajectories
We present theoretical arguments and strong phenomenological evidence that
hadronic Regge trajectories are essentially nonlinear and can be well
approximated, for phenomenological purposes, by a specific square-root form.Comment: 29 pages, LaTeX. Published versio