1,358 research outputs found
On the forward-backward correlations in a two-stage scenario
It is demonstrated that in a two-stage scenario with elementary Poissonian
emitters of particles (colour strings) arbitrarily distributed in their number
and average multiplicities, the forward- backward correlations are completely
determined by the final distribution of the forward particles. The observed
linear form of the correlations then necessarily requires this distribution to
have a negative binomial form. For emitters with a negative binomial
distribution of the produced particles distributed so as to give the final
distribution also of a negative binomial form, the forward-backward
correlations have an essentially non-linear form, which disagrees with the
experimental data.Comment: 14 pages in LaTex, 1 figure in Postscrip
Energy dependence of transverse mass spectra of kaons produced in p+p and p+pbar interactions.A compilation
The data on m_T spectra of K0S K+ and K- mesons produced in all inelastic p+p
and p+pbar interactions in the energy range sqrt(s)NN=4.7-1800GeV are compiled
and analyzed. The spectra are parameterized by a single exponential function,
dN/(m_T*dm_T)=C exp(-m_T/T), and the inverse slope parameter T is the main
object of study. The T parameter is found to be similar for K0S, K+ and K-
mesons. It increases monotonically with collision energy from T~30MeV at
sqrt(s)NN=4.7GeV to T~220MeV at sqrt(s)NN=1800GeV. The T parameter measured in
p+p and p+pbar interactions is significantly lower than the corresponding
parameter obtained for central Pb+Pb collisions at all studied energies. Also
the shape of the energy dependence of is different for central Pb+Pb
collisions and p+p(pbar) interactions.Comment: more differential analysis adde
Multiparticle production in the model with antishadowing
We discuss the role of absorbtion and antishadowing in particle production.
We reproduce power-like energy behavior of the mean multiplicity in the model
with antishadowing and discuss physical implications of such behavior for the
hadron structure.Comment: 11 pages, 3 figures, extended version of the talk at the XXXII
International Symposium on Multiparticle Dynamics September 7-13, 2002
Alushta, Crimea, Ukrain
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
Clan Structure Analysis and Rapidity Gap Probability
Clan structure analysis in rapidity intervals is generalized from negative
binomial multiplicity distribution to the wide class of compound Poisson
distributions. The link of generalized clan structure analysis with correlation
functions is also established. These theoretical results are then applied to
minimum bias events and evidentiate new interesting features, which can be
inspiring and useful in order to discuss data on rapidity gap probability at
TEVATRON and HERA.Comment: (14 pages in Plain TeX plus 5 Postscript Figures, all compressed via
uufiles) DFTT 28/9
Estimating the inelasticity with the information theory approach
Using the information theory approach, in both its extensive and nonextensive
versions, we estimate the inelasticity parameter of hadronic reactions
together with its distribution and energy dependence from and
data. We find that the inelasticity remains essentially constant in energy
except for a variation around , as was originally expected.Comment: 14 pages, 8 figures. Misprints correcte
Clan structure analysis and new physics signals in pp collisions at LHC
The study of possible new physics signals in global event properties in pp
collisions in full phase space and in rapidity intervals accessible at LHC is
presented. The main characteristic is the presence of an elbow structure in
final charged particle MD's in addition to the shoulder observed at lower c.m.
energies.Comment: 9 pages, talk given at Focus on Multiplicity (Bari, Italy, June 2004
Multiplicity Distributions and Rapidity Gaps
I examine the phenomenology of particle multiplicity distributions, with
special emphasis on the low multiplicities that are a background in the study
of rapidity gaps. In particular, I analyze the multiplicity distribution in a
rapidity interval between two jets, using the HERWIG QCD simulation with some
necessary modifications. The distribution is not of the negative binomial form,
and displays an anomalous enhancement at zero multiplicity. Some useful
mathematical tools for working with multiplicity distributions are presented.
It is demonstrated that ignoring particles with pt<0.2 has theoretical
advantages, in addition to being convenient experimentally.Comment: 24 pages, LaTeX, MSUHEP/94071
Studying the impact of ocean eddies on the ecosystem of the Prince Edward Islands: DEIMEC ll
The Dynamics of Eddy Impacts on Marion’s Ecosystem Study (DEIMEC) programme was begun in 2002 with the aim of understanding the importance of the oceanic, upstream environment to the ecosystem of the Prince Edward Islands. This island group consists of two small volcanic islands and provides many opportunities for studying ecological and evolutionary processes, for monitoring ecological changes in relation to global climate change and for conserving a unique component of the planet’s biological diversity
Conserving pattern and process in the Southern Ocean: designing a Marine Protected Area for the Prince Edward Islands
South Africa is currently proclaiming a Marine Protected Area (MPA) in the Exclusive Economic Zone (EEZ) of its sub-Antarctic Prince Edward Islands. The objectives of the MPA are to: 1) contribute to a national and global representative system of MPAs, 2) serve as a scientific reference point to inform future management, 3) contribute to the recovery of the Patagonian toothfish (Dissostichus eleginoides), and 4) reduce the bird bycatch of the toothfish fishery, particularly of albatrosses and petrels. This study employs systematic conservation planning methods to delineate a MPA within the EEZ that will conserve biodiversity patterns and processes within sensible management boundaries, while minimizing conflict with the legal toothfish fishery. After collating all available distributional data on species, benthic habitats and ecosystem processes, we used C-Plan software to delineate a MPA with three management zones: four IUCN Category Ia reserves (13% of EEZ); two Conservation Zones (21% of EEZ); and three Category IV reserves (remainder of EEZ). Compromises between conservation target achievement and the area required by the MPA are apparent in the final reserve design. The proposed MPA boundaries are expected to change over time as new data become available and as impacts of climate change become more evident
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