989 research outputs found
A Color Mutation Model of Soft Interaction in High Energy Hadronic Collisions
A comprehensive model, called ECOMB, is proposed to describe multiparticle
production by soft interaction. It incorporates the eikonal formalism, parton
model, color mutation, branching and recombination. The physics is conceptually
opposite to the dynamics that underlies the fragmentation of a string. The
partons are present initially in a hadronic collision; they form a single,
large, color-neutral cluster until color mutation of the quarks leads to a
fission of the cluster into two color-neutral subclusters. The mutation and
branching processes continue until only pairs are left in each small
cluster. The model contains self-similar dynamics and exhibits scaling behavior
in the factorial moments. It can satisfactorily reproduce the intermittency
data that no other model has been able to fit.Comment: 24 pages including 11 figures in revtex epsf styl
Nonextensive Statistics and Multiplicity Distribution in Hadronic Collisions
The multiplicity distribution of particles in relativistic gases is studied
in terms of Tsallis' nonextensive statistics. For an entropic index q>1 the
multiplicity distribution is wider than the Poisson distribution with the same
average number of particles, being similar to the negative binomial
distribution commonly used in phenomenological analysis of hadron production in
high-energy collisions
Transesterification of PHA to Oligomers Covalently Bonded with (Bio)Active Compounds Containing Either Carboxyl or Hydroxyl Functionalities
© 2015 The Authors. Published by Public Library of Science. This is an open access article available under a Creative Commons licence.
The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0120149This manuscript presents the synthesis and structural characterisation of novel biodegradable polymeric controlled-release systems of pesticides with potentially higher resistance to weather conditions in comparison to conventional forms of pesticides. Two methods for the preparation of pesticide-oligomer conjugates using the transesterification reaction were developed. The first method of obtaining conjugates, which consist of bioactive compounds with the carboxyl group and polyhydroxyalkanoates (PHAs) oligomers, is "one-pot" transesterification. In the second method, conjugates of bioactive compounds with hydroxyl group and polyhydroxyalkanoates oligomers were obtained in two-step method, through cyclic poly(3-hydroxybutyrate) oligomers. The obtained pesticide-PHA conjugates were comprehensively characterised using GPC, 1H NMR and mass spectrometry techniques. The structural characterisation of the obtained products at the molecular level with the aid of mass spectrometry confirmed that both of the synthetic strategies employed led to the formation of conjugates in which selected pesticides were covalently bonded to PHA oligomers via a hydrolysable ester bond
Scenarios for multiplicity distributions in pp collisions in the TeV energy region
Possible scenarios based on available experimental data and phenomenological
knowledge of the GeV energy region are extended to the TeV energy region in the
framework of the weighted superposition mechanism of soft and semi-hard events.
KNO scaling violations, forward-backward multiplicity correlations, Hq vs. q
oscillations and shoulder structures are discussed.Comment: 10 pages, 10 figures, talk given at "Focus on Multiplicity" (Bari,
Italy, June 2004
Hadronic sizes and observables in high-energy scattering
The functional dependence of the high-energy observables of total cross
section and slope parameter on the sizes of the colliding hadrons predicted by
the model of the stochastic vacuum and the corresponding relations used in the
geometric model of Povh and H\"ufner are confronted with the experimental data.
The existence of a universal term in the expression for the slope, due purely
to vacuum effects, independent of the energy and of the particular hadronic
system, is investigated. Accounting for the two independent correlation
functions of the QCD vacuum, we improve the simple and consistent description
given by the model of the stochastic vacuum to the high-energy pp and pbar-p
data, with a new determination of parameters of non-perturbative QCD. The
increase of the hadronic radii with the energy accounts for the energy
dependence of the observables.Comment: Latex, using Revtex.style . 2 ps figures. To be published in Physical
Review D , July 199
Charged rho meson production in neutrino-induced reactions at E_nu = 10 GeV
The neutrinoproduction of charged mesons on nuclei and nucleons is
investigated for the first time at moderate energies ( 10
GeV), using the date obtained with SKAT bubble chamber. No strong nuclear
effects are observed in and production. The fractions of
charged and neutral pions originating from decays are obtained and
compared with higher energy data. From analysis of the obtained and available
data on and (892) neutrinoproduction, the strangeness
suppression factor in the quark string fragmentation is extracted: . Estimations are obtained for cross sections of quasiexclusive
single and coherent neutrinoproduction on nuclei. The
estimated coherent cross section = (0.29 cm is compatible with theoretical predictions.Comment: 7 pages, 6 figure
Next-to-Leading Order Constituent Quark Structure and Hadronic Structure Functions
We calculate the partonic structure of a constituent quark in the
Next-to-Leading Order framework. The structure of any hadron can be obtained
thereafter using a convolution method. Such a procedure is used to generate the
structure function of proton and pion in NLO, neglecting certain corrections to
. It is shown that while the constituent quark structure is
generated purely perturbatively and accounts for the most part of the hadronic
structure, there is a few percent contributions coming from the nonperturbative
sector in the hadronic structure. This contribution plays the key role in
explaining the SU(2) symmetry breaking of the nucleon sea and the observed
violation of Gottfried sum rule. These effects are calculated. We obtained an
Excellent agreement with the experimental data in a wide range of and for the proton structure function. We
have also calculated Pion structure and compared it with the existing data.
Again, the model calculations agree rather well with the data from experiment.Comment: 32 pages,10 figures, Accepted to publish in Phys. Rev.
A case of paraneoplastic optic neuropathy and outer retinitis positive for autoantibodies against collapsin response mediator protein-5, recoverin, and α-enolase
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