27,949 research outputs found
Unitarity of the tree approximation to the Glauber AA amplitude for large A
The nucleus-nucleus Glauber amplitude in the tree approximation is studied
for heavy participant nuclei. It is shown that, contrary to previous published
results, it is not unitary for realistic values of nucleon-nucleon
cross-sections.Comment: 15 pages, 1 figure, 1 table. Submitted to Yad. Fi
Statistical hadronization of charm at SPS, RHIC and LHC
We study the production of charmonia and charmed hadrons for nucleus-nucleus
collisions at SPS, RHIC, and LHC energies within the framework of the
statistical hadronization model. Results from this model are compared to the
observed centrality dependence of J/psi production at SPS energy. We further
provide predictions for the centrality dependence of the production of open and
hidden charm mesons at RHIC and LHC.Comment: Contribution to Quark Matter 2002, 4 pages, 3 figures; revised
version including charmed hyperons (omitted in v1
The statistical model in Pb-Pb collisions at the LHC
We briefly review the predictions of the thermal model for hadron production
in comparison to latest data from RHIC and extrapolate the calculations to LHC
energy. Our main emphasis is to confront the model predictions with the
recently released data from ALICE at the LHC. This comparison reveals an
apparent anomaly for protons and anti-protons which we discuss briefly. We also
demonstrate that our statistical hadronization predictions for J/
production agree very well with the most recent LHC data, lending support to
the picture in which there is complete charmonium melting in the quark-gluon
plasma (QGP) followed by statistical generation of J/ mesons at the phase
boundary.Comment: 4 pages, 3 figures, proceedings of QM201
Fluctuations of the number of participants and binary collisions in AA interactions at fixed centrality in the Glauber approach
In the framework of the classical Glauber approach, the analytical
expressions for the variance of the number of wounded nucleons and binary
collisions in AA interactions at a given centrality are presented. Along with
the optical approximation term, they contain additional contact terms arising
only in the case of nucleus-nucleus collisions. The magnitude of the additional
contributions, e.g., for PbPb collisions at SPS energies, is larger than the
contribution of the optical approximation at some values of the impact
parameter. The sum of the additional contributions is in good agreement with
the results of independent Monte Carlo simulations of this process. Due to
these additional terms, the variance of the total number of participants for
peripheral PbPb collisions and the variance of the number of collisions at all
values of the impact parameter exceed several multiples of the Poisson
variances. The correlator between the numbers of participants in colliding
nuclei at fixed centrality is also analytically calculated.Comment: updated version; as published by Phys. Rev.
Confronting LHC data with the statistical hadronization model
The most recent data from the CERN LHC are compared with calculations within
the statistical hadronization model. The parameters temperature und baryon
chemical potential are fitted to the data. The best fit yields a temperature of
156 MeV, slightly below the expectation from RHIC data. Proton yields are
nearly three standard deviations below this fit and possible reasons are
discussed.Comment: Proceedings of Strange Quark Matter 2013 Conference, to be published
in J. Phys.
Enhanced response of the regular networks to local signals in presence of a fast impurity
We consider an array of inductively coupled Josephson junctions with a fast
impurity (a junction with a smaller value of critical current), and study the
consequences of imposing a small amplitude periodic signal at some point in the
array. We find that when external signal is imposed at the impurity, the
response of the array is boosted and a small amplitude signal can be detected
throughout the array. When the signal is imposed elsewhere, minor effects is
seen on the dynamics of the array. The same results have been also seen in
presence of a single fast spiking neuron in a chain of diffusively coupled
FitzHugh-Nagumo neurons.Comment: 6 pages, 5 figures, arXiv admin note: substantial text overlap with
arXiv:1108.460
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