3,171 research outputs found
Quark liberation and coalescence at CERN SPS
The mischievous linear coalescence approach to hadronization of quark matter
is shown to violate strangeness conservation in strong interactions. The
simplest correct quark counting is shown to coincide with the non-linear
algebraic coalescence rehadronization model, ALCOR. The non-linearity of the
ALCOR model is shown to cancel from its simple predictions for the relative
yields of (multi-)strange baryons. We prove, model independently, that quark
degrees of freedom are liberated before hadron formation in 158 AGeV central Pb
+ Pb collisions at CERN SPS.Comment: Latex file, 6 pages, improved text and conclusio
Entropy of expanding QCD matter
Using the lattice QCD equation of state for an isentropically expanding
fireball we follow the evolution of the effective number of particles in an
ideal gas pV/T. This number reduces roughly to its third around the crossover
temperature, which helps to circumvent the entropy obstacle inherent in quark
coalescence models of the hadronization.Comment: 5 pages 4 eps figures LaTe
Observables of Lattice Gauge Theory in Minkowski Space
U(1) gauge fields are decomposed into a monopole and photon part across the
phase transition from the confinement to the Coulomb phase. We analyze the
leading Lyapunov exponents of such gauge field configurations on the lattice
which are initialized by quantum Monte Carlo simulations. We observe that the
monopole field carries the same Lyapunov exponent as the original U(1) field.
Evidence is found that monopole fields stay chaotic in the continuum whereas
the photon fields are regular. First results are presented for the full
spectrum of Lyapunov exponents of the U(1) gauge system.Comment: Contribution to "QCD02 - High-Energy Physics International Conference
in Quantum Chromodynamics" (Montpellier, France, July 02 - 09, 2002); 5
pages, 9 figure
Properties of quark matter produced in heavy ion collision
We describe the hadronization of quark matter assuming that quarks creating
hadrons coalesce from a continuous mass distribution. The pion and antiproton
spectrum as well as the momentum dependence of the antiproton to pion ratio are
calculated. This model reproduces fairly well the experimental data at RHIC
energies.Comment: 9 pages, 6 Postscript figures, typos are correcte
College admissions with stable score-limits
A common feature of the Hungarian, Irish, Spanish and Turkish higher education
admission systems is that the students apply for programmes and they are ranked according
to their scores. Students who apply for a programme with the same score are in a tie. Ties
are broken by lottery in Ireland, by objective factors in Turkey (such as date of birth) and
other precisely defined rules in Spain. In Hungary, however, an equal treatment policy is
used, students applying for a programme with the same score are all accepted or rejected
together. In such a situation there is only one question to decide, whether or not to admit
the last group of applicants with the same score who are at the boundary of the quota. Both
concepts can be described in terms of stable score-limits. The strict rejection of the last group with whom a quota would be violated corresponds to the concept of H-stable (i.e.
higher-stable) score-limits that is currently used in Hungary. We call the other solutions
based on the less strict admission policy as L-stable (i.e. lower-stable) score-limits. We show
that the natural extensions of the Gale-Shapley algorithms produce stable score-limits,
moreover, the applicant-oriented versions result in the lowest score-limits (thus optimal for
students) and the college-oriented versions result in the highest score-limits with regard to
each concept. When comparing the applicant-optimal H-stable and L-stable score-limits
we prove that the former limits are always higher for every college. Furthermore, these two solutions provide upper and lower bounds for any solution arising from a tie-breaking
strategy. Finally we show that both the H-stable and the L-stable applicant-proposing scorelimit
algorithms are manipulable
Thermodynamics and flow-frames for dissipative relativistic fluids
A general thermodynamic treatment of dissipative relativistic fluids is
introduced, where the temperature four vector is not parallel to the velocity
field of the fluid. Generic stability and kinetic equilibrium points out a
particular thermodynamics, where the temperature vector is parallel to the
enthalpy flow vector and the choice of the flow fixes the constitutive
functions for viscous stress and heat. The linear stability of the homogeneous
equilibrium is proved in a mixed particle-energy flow-frame.Comment: 9 page
Equilibrium distributions in entropy driven balanced processes
For entropy driven balanced processes we obtain final states with Poisson,
Bernoulli, negative binomial and P\'olya distributions. We apply this both for
complex networks and particle production. For random networks we follow the
evolution of the degree distribution, , in a system where a node can
activate fixed connections from possible partnerships among all nodes.
The total number of connections, , is also fixed. For particle physics
problems is the probability of having particles (or other quanta)
distributed among states (phase space cells) while altogether a fixed
number of particles reside on states.Comment: 12 pages no figure
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