2,201 research outputs found
Charmed Hadrons from Strangeness-rich QGP
The yields of charmed hadrons emitted by strangeness rich QGP are evaluated
within chemical non-equilibrium statistical hadronization model, conserving
strangeness, charm, and entropy yields at hadronization.Comment: 6 pages, 2 figures SQM 2006; the same as J. Phys. G in pres
Rapidity particle spectra in sudden hadronization of QGP
We show that the remaining internal longitudinal flow of colliding quarks in
nuclei offers a natural explanation for the diversity of rapidity spectral
shapes observed in Pb--Pb 158AGeV nuclear collisions. Thus QGP sudden
hadronization reaction picture is a suitable approach to explain the rapidity
spectra of hadrons produced.Comment: 3 pages including 2 figure
Strangeness, Equilibration, Hadronization
In these remarks I explain the motivation which leads us to consider chemical
nonequilibrium processes in flavor equilibration and in statistical
hadroniziation of quark--gluon plasma (QGP). Statistical hadronization allowing
for chemical non-equilibrium is introduced. The reesults of fits to
RHIC-130 results, including multistrange hadrons, are shown to agree only
with the model of an exploding QGP fireball.Comment: 8 pages including one figure, discussion contribution at Strange
Quark Matter 2001, Frankfurt, submitted to J. Phys.
Extending starter motor life via optimization of commutation system parmeters
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1994, and Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, 1994.Includes bibliographical references (p. 60).by G. Johann R. Ochoco.M.S
Estratégias de comercialização do feijão produzido por agricultores familiares da região Leste de Goiás.
A pesquisa teve como objetivo principal identificar as estratégias de comercialização do feijão oriundo da agricultura familiar, assim como a principal safra, as variedades produzidas e o destino dessa produção de feijão.CONAF
Equilibrium Distribution of Heavy Quarks in Fokker-Planck Dynamics
We obtain within Fokker-Planck dynamics an explicit generalization of
Einstein's relation between drag, diffusion and equilibrium distribution for a
spatially homogeneous system, considering both the transverse and longitudinal
diffusion for dimension n>1. We then provide a complete characterization of
when the equilibrium distribution becomes a Boltzmann/J"uttner distribution,
and when it satisfies the more general Tsallis distribution. We apply this
analysis to recent calculations of drag and diffusion of a charm quark in a
thermal plasma, and show that only a Tsallis distribution describes the
equilibrium distribution well. We also provide a practical recipe applicable to
highly relativistic plasmas, for determining both diffusion coefficients so
that a specific equilibrium distribution will arise for a given drag
coefficient.Comment: 4 pages including 2 figure
Legitimating inaction : differing identity constructions of the Scots language.
The Scots language plays a key role in the political and cultural landscape of contemporary Scotland. From a discourse-historical perspective, this article explores how language ideologies about the Scots language are realized linguistically in a so-called ‘languages strategy’ drafted by the Scottish Executive, and in focus groups consisting of Scottish people. This article shows that although the decline of Scots is said to be a ‘tragedy’, focus group participants seem to reject the notion of Scots as a viable, contemporary language that can be used across a wide range of registers. The policy document also seems to construct Scots in very positive terms, but is shown to be unhelpful or potentially even damaging in the process of changing public attitudes to Scots
Two-Loop Sudakov Form Factor in a Theory with Mass Gap
The two-loop Sudakov form factor is computed in a U(1) model with a massive
gauge boson and a model with mass gap. We analyze the result
in the context of hard and infrared evolution equations and establish a
matching procedure which relates the theories with and without mass gap setting
the stage for the complete calculation of the dominant two-loop corrections to
electroweak processes at high energy.Comment: Latex, 5 pages, 2 figures. Bernd Feucht is Bernd Jantzen in later
publications. (The contents of the paper is unchanged.
Particle yield fluctuations and chemical non-equilibrium at RHIC
We study charge fluctuations within the statistical hadronization model.
Considering both the particle yield ratios and the charge fluctuations we show
that it is possible to differentiate between chemical equilibrium and
non-equilibrium freeze-out conditions. As an example of the procedure we show
quantitatively how the relative yield ratio together with the
normalized net charge fluctuation v(Q)=\ave{\Delta Q^2}/\ave{\Nch} constrain
the chemical conditions at freeze-out. We also discuss the influence of the
limited detector acceptance on fluctuation measurements, and show how this can
be accounted for within a quantitative analysis.Comment: Accepted for publication by Physical Review
Generic Fibrational Induction
This paper provides an induction rule that can be used to prove properties of
data structures whose types are inductive, i.e., are carriers of initial
algebras of functors. Our results are semantic in nature and are inspired by
Hermida and Jacobs' elegant algebraic formulation of induction for polynomial
data types. Our contribution is to derive, under slightly different
assumptions, a sound induction rule that is generic over all inductive types,
polynomial or not. Our induction rule is generic over the kinds of properties
to be proved as well: like Hermida and Jacobs, we work in a general fibrational
setting and so can accommodate very general notions of properties on inductive
types rather than just those of a particular syntactic form. We establish the
soundness of our generic induction rule by reducing induction to iteration. We
then show how our generic induction rule can be instantiated to give induction
rules for the data types of rose trees, finite hereditary sets, and
hyperfunctions. The first of these lies outside the scope of Hermida and
Jacobs' work because it is not polynomial, and as far as we are aware, no
induction rules have been known to exist for the second and third in a general
fibrational framework. Our instantiation for hyperfunctions underscores the
value of working in the general fibrational setting since this data type cannot
be interpreted as a set.Comment: For Special Issue from CSL 201
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