62 research outputs found
Lattice QCD Constraints on the Nuclear Equation of State
Based on the quasi-particle description of the QCD medium at finite
temperature and density we formulate the phenomenological model for the
equation of state that exhibits crossover or the first order deconfinement
phase transition. The models are constructed in such a way to be
thermodynamically consistent and to satisfy the properties of the ground state
nuclear matter comply with constraints from intermediate heavy--ion collision
data. Our equations of states show quite reasonable agreement with the recent
lattice findings on temperature and baryon chemical potential dependence of
relevant thermodynamical quantities in the parameter range covering both the
hadronic and quark--gluon sectors. The model predictions on the isentropic
trajectories in the phase diagram are shown to be consistent with the recent
lattice results. Our nuclear equations of states are to be considered as an
input to the dynamical models describing the production and the time evolution
of a thermalized medium created in heavy ion collisions in a broad energy range
from SIS up to LHC.Comment: 13 pages, 11 figure
Neutrino Emission from Goldstone Modes in Dense Quark Matter
We calculate neutrino emissivities from the decay and scattering of Goldstone
bosons in the color-flavor-locked (CFL) phase of quarks at high baryon density.
Interactions in the CFL phase are described by an effective low-energy theory.
For temperatures in the tens of keV range, relevant to the long-term cooling of
neutron stars, the emissivities involving Goldstone bosons dominate over those
involving quarks, because gaps in the CFL phase are MeV while the
masses of Goldstone modes are on the order of 10 MeV. For the same reason, the
specific heat of the CFL phase is also dominated by the Goldstone modes.
Notwithstanding this, both the emissivity and the specific heat from the
massive modes remain rather small, because of their extremely small number
densities. The values of the emissivity and the specific heat imply that the
timescale for the cooling of the CFL core in isolation is y,
which makes the CFL phase invisible as the exterior layers of normal matter
surrounding the core will continue to cool through significantly more rapid
processes. If the CFL phase appears during the evolution of a proto-neutron
star, neutrino interactions with Goldstone bosons are expected to be
significantly more important since temperatures are high enough (
MeV) to admit large number densities of Goldstone modes.Comment: 29 pages, no figures. slightly modified text, one new eqn. and new
refs. adde
Two lectures on color superconductivity
The first lecture provides an introduction to the physics of color
superconductivity in cold dense quark matter. The main color superconducting
phases are briefly described and their properties are listed. The second
lecture covers recent developments in studies of color superconducting phases
in neutral and beta-equilibrated matter. The properties of gapless color
superconducting phases are discussed.Comment: 56 pages, 9 figures. Minor corrections and references added. Lectures
delivered at the IARD 2004 conference, Saas Fee, Switzerland, June 12 - 19,
2004, and at the Helmholtz International Summer School and Workshop on Hot
points in Astrophysics and Cosmology, JINR, Dubna, Russia, August 2 - 13,
200
Chemical freeze-out of light nuclei in high energy nuclear collisions and resolution of the hyper-Triton chemical freeze-out puzzle
Indexación ScopusWe present a summary of the recent results obtained with the novel hadron resonance gas model with the multicomponent hard-core repulsion which is extended to describe the mixtures of hadrons and light (anti-, hyper-)nuclei. A very accurate description is obtained for the hadronic and the light nuclei data measured by STAR at the collision energy The most striking result discussed here is that for the most probable chemical freeze-out scenario for the STAR energy the found parameters allow us to reproduce the values of the experimental ratios S 3 and without fitting. © Published under licence by IOP Publishing Ltd.https://iopscience-iop-org.recursosbiblioteca.unab.cl/article/10.1088/1742-6596/1690/1/01212
Quantum Vacuum Experiments Using High Intensity Lasers
The quantum vacuum constitutes a fascinating medium of study, in particular
since near-future laser facilities will be able to probe the nonlinear nature
of this vacuum. There has been a large number of proposed tests of the
low-energy, high intensity regime of quantum electrodynamics (QED) where the
nonlinear aspects of the electromagnetic vacuum comes into play, and we will
here give a short description of some of these. Such studies can shed light,
not only on the validity of QED, but also on certain aspects of nonperturbative
effects, and thus also give insights for quantum field theories in general.Comment: 9 pages, 8 figur
Kaon properties in (proto)neutron stars
The modification on kaon and antikaon properties of in the interior of
(proto-)neutron stars is investigated using a chiral SU(3) model. The
parameters of the model are fitted to nuclear matter saturation properties,
baryon octet vacuum masses, hyperon optical potentials and low energy a
kaon-nucleon scattering lengths. We study the kaon/antikaon medium modification
and explore the possibility of antikaon condensation in (proto-)neutron star
matter at zero as well as finite temperature/entropy and neutrino content. The
effect of hyperons on kaon and antikaon optical potentials is also investigated
at different stages of the neutron star evolution.Comment: 17 pages including 4 figure
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