2,488 research outputs found
Evolution of non-stationary pulses in a cold magnetized quark-gluon plasma
We study weakly nonlinear wave perturbations propagating in a cold
nonrelativistic and magnetized ideal quark-gluon plasma. We show that such
perturbations can be described by the Ostrovsky equation. The derivation of
this equation is presented for the baryon density perturbations. Then we show
that the generalized nonlinear Schr{\"o}dinger (NLS) equation can be derived
from the Ostrovsky equation for the description of quasi-harmonic wave trains.
This equation is modulationally stable for the wave number and
unstable for , where is the wave number where the group velocity
has a maximum. We study numerically the dynamics of initial wave packets with
the different carrier wave numbers and demonstrate that depending on the
initial parameters they can evolve either into the NLS envelope solitons or
into dispersive wave trains
vertex from QCD sum rules
The form factors and the coupling constant of the vertex are
calculated using the QCD sum rules method. Three point correlation functions
are computed considering both and mesons off-shell and, after an
extrapolation of the QCDSR results, we obtain the coupling constant of the
vertex. We study the uncertainties in our result by calculating a third form
factor obtained when the is the off-shell meson, considering other
acceptable structures and computing the variations of the sum rules'
parameters. The form factors obtained have different behaviors but their
simultaneous extrapolations reach to the same value of the coupling constant
. We compare our result with other theoretical
estimates.Comment: 11 pages, 11 figure
Preface: The SINTEX Project
The project called Decadal and Interdecadal Climate Variability: Scales Interactions Experiments (SINTEX), was conceived in 1997, stemming from a series of discussions and meetings within The EUROCLIVAR..
Self-bound Interacting QCD Matter in Compact Stars
The quark gluon plasma (QGP) at zero temperature and high baryon number is a
system that may be present inside compact stars. It is quite possible that this
cold QGP shares some relevant features with the hot QGP observed in heavy ion
collisions, being also a strongly interacting system. In a previous work we
have derived from the QCD Lagrangian an equation of state (EOS) for the cold
QGP, which can be considered an improved version of the MIT bag model EOS.
Compared to the latter, our equation of state reaches higher values of the
pressure at comparable baryon densities. This feature is due to perturbative
corrections and also to non-perturbative effects. Here we apply this EOS to the
study of neutron stars, discussing the absolute stability of quark matter and
computing the mass-radius relation for self-bound (strange) stars. The maximum
masses of the sequences exceed two solar masses, in agreement with the recently
measured values of the mass of the pulsar PSR J1614-2230, and the corresponding
radii around 10-11 km
Production of exotic charmonium in interactions at hadronic colliders
In this paper we investigate the Exotic Charmonium (EC) production in interactions present in proton-proton, proton-nucleus and
nucleus-nucleus collisions at the CERN Large Hadron Collider (LHC) energies as
well as for the proposed energies of the Future Circular Collider (FCC). Our
results demonstrate that the experimental study of these processes is feasible
and can be used to constrain the theoretical decay widths and shed some light
on the configuration of the considered multiquark states.Comment: 7 pages, 2 figures, 3 tables. v2: Revised version published in
Physical Review
- …