1,304 research outputs found
What is the meaning of the statistical hadronization model?
The statistical model of hadronization succeeds in reproducing particle
abundances and transverse momentum spectra in high energy collisions of
elementary particles as well as of heavy ions. Despite its apparent success,
the interpretation of these results is controversial and the validity of the
approach very often questioned. In this paper, we would like to summarize the
whole issue by first outlining a basic formulation of the model and then
comment on the main criticisms and different kinds of interpretations, with
special emphasis on the so-called "phase space dominance". While the ultimate
answer to the question why the statistical model works should certainly be
pursued, we stress that it is a priority to confirm or disprove the fundamental
scheme of the statistical model by performing some detailed tests on the rates
of exclusive channels at lower energy.Comment: 14 pages, to be published in the Proceedings of the International
workshop "Focus on multiplicity", Bari (Italy) June 17-19 200
Quantum Collective QCD String Dynamics
The string breaking model of particle production is extended in order to help
explain the transverse momentum distribution in elementary collisions. Inspired
by an idea of Bialas', we treat the string using a collective coordinate
approach. This leads to a chromo-electric field strength which fluctuates, and
in turn implies that quarks are produced according to a thermal distribution.Comment: 6 pages. Presented at SQM 2006. Submitted to J. Phys. G for
publication in proceedings. Vers. 2: Minor revisions; final hadron spectrum
calculation include
Erratum to: General equilibrium second-order hydrodynamic coefficients for free quantum fields
In section 3, the partition function is included in the definition of the statistical operator
Strange quark production in a statistical effective model
An effective model with constituent quarks as fundamental degrees of freedom
is used to predict the relative strangeness production pattern in both high
energy elementary and heavy ion collisions. The basic picture is that of the
statistical hadronization model, with hadronizing color-singlet clusters
assumed to be at full chemical equilibrium at constituent quark level. Thus, by
assuming that at least the ratio between strange and non-strange constituent
quarks survives in the final hadrons, the apparent undersaturation of strange
particle phase space observed in the data can be accounted for. In this
framework, the enhancement of relative strangeness production in heavy ion
collisions in comparison with elementary collisions is mainly owing to the
excess of initial non-strange matter over antimatter and the so-called
canonical suppression, namely the constraint of exact color and flavor
conservation over small volumes.Comment: 22 pages, 9 postscript figures, slightly shortened version published
in Phys. Rev.
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