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Performance of Density Functional Theory for 3d Transition Metal-Containing Complexes: Utilization of the Correlation Consistent Basis Sets
Article discussing the performance of density functional theory for 3d transition metal-containing complexes and the utilization of the correlation consistent basis sets
Results on correlations and fluctuations from NA49
The large acceptance and high momentum resolution as well as the significant
particle identification capabilities of the NA49 experiment at the CERN SPS
allow for a broad study of fluctuations and correlations in hadronic
interactions. In the first part recent results on event-by-event charge and p_t
fluctuations are presented. Charge fluctuations in central Pb+Pb reactions are
investigated at three different beam energies (40, 80, and 158 AGeV), while for
the p_t fluctuations the focus is put on the system size dependence at 158
AGeV. In the second part recent results on Bose Einstein correlations of h-h-
pairs in minimum bias Pb+Pb reactions at 40 and 158 AGeV, as well as of K+K+
and K-K- pairs in central Pb+Pb collisions at 158 AGeV are shown. Additionally,
other types of two particle correlations, namely pi p, Lambda p, and Lambda
Lambda correlations, have been measured by the NA49 experiment. Finally,
results on the energy and system size dependence of deuteron coalescence are
discussed.Comment: 10 pages, 12 figures, Presented at Quark Matter 2002, Nantes, France,
Corrected error in Eq.
Bose-Einstein Correlations of Charged Kaons in Central Pb+Pb Collisions at
Bose-Einstein correlations of charged kaons were measured near mid-rapidity
in central Pb+Pb collisions at 158 AGeV by the NA49 experiment at the
CERN SPS. Source radii were extracted using the Yano-Koonin-Podgoretsky and
Bertsch-Pratt parameterizations. The results are compared to published pion
data. The measured dependence for kaons and pions is consistent with
collective transverse expansion of the source and a freeze-out time of about
9.5 .Comment: 14 pages with 7 figures, submitted to Phys. Lett.
Lambda production in central Pb+Pb collisions at CERN-SPS energies
In this paper we present recent results from the NA49 experiment for
and hyperons produced in central Pb+Pb collisions at
40, 80 and 158 AGeV. Transverse mass spectra and rapidity distributions
for are shown for all three energies. The shape of the rapidity
distribution becomes flatter with increasing beam energy. The multiplicities at
mid-rapidity as well as the total yields are studied as a function of collision
energy including AGS measurements. The ratio at mid-rapidity and
in 4 has a maximum around 40 AGeV. In addition,
rapidity distributions have been measured at 40 and 80 AGeV, which
allows to study the / ratio.Comment: SQM proceedings. J. Phys. G: Nucl. Part. Phys.: submitte
Ricci curvature of finite Markov chains via convexity of the entropy
We study a new notion of Ricci curvature that applies to Markov chains on
discrete spaces. This notion relies on geodesic convexity of the entropy and is
analogous to the one introduced by Lott, Sturm, and Villani for geodesic
measure spaces. In order to apply to the discrete setting, the role of the
Wasserstein metric is taken over by a different metric, having the property
that continuous time Markov chains are gradient flows of the entropy.
Using this notion of Ricci curvature we prove discrete analogues of
fundamental results by Bakry--Emery and Otto--Villani. Furthermore we show that
Ricci curvature bounds are preserved under tensorisation. As a special case we
obtain the sharp Ricci curvature lower bound for the discrete hypercube.Comment: 39 pages, to appear in Arch. Ration. Mech. Ana
Event-by-event fluctuations of the kaon to pion ratio in central Pb+Pb collisions at 158 GeV per Nucleon
We present the first measurement of fluctuations from event to event in the
production of strange particles in collisions of heavy nuclei. The ratio of
charged kaons to charged pions is determined for individual central Pb+Pb
collisions. After accounting for the fluctuations due to detector resolution
and finite number statistics we derive an upper limit on genuine
non-statistical fluctuations, perhaps related to a first or second order QCD
phase transition. Such fluctuations are shown to be very small.Comment: 4 pages, 2 figure
Two-proton correlations from 158 AGeV Pb+Pb central collisions
The two-proton correlation function at midrapidity from Pb+Pb central
collisions at 158 AGeV has been measured by the NA49 experiment. The results
are compared to model predictions from static thermal Gaussian proton source
distributions and transport models RQMD and VENUS. An effective proton source
size is determined by minimizing CHI-square/ndf between the correlation
functions of the data and those calculated for the Gaussian sources, yielding
3.85 +-0.15(stat.) +0.60-0.25(syst.) fm. Both the RQMD and the VENUS model are
consistent with the data within the error in the correlation peak region.Comment: RevTeX style, 6 pages, 4 figures, 1 table. More discussion are added
about the structure on the tail of the correlation function. The systematic
error is revised. To appear in Phys. Lett.
Event-by-event fluctuations of average transverse momentum in central Pb+Pb collisions at 158 GeV per nucleon
We present first data on event-by-event fluctuations in the average
transverse momentum of charged particles produced in Pb+Pb collisions at the
CERN SPS. This measurement provides previously unavailable information allowing
sensitive tests of microscopic and thermodynamic collision models and to search
for fluctuations expected to occur in the vicinity of the predicted QCD phase
transition. We find that the observed variance of the event-by-event average
transverse momentum is consistent with independent particle production modified
by the known two-particle correlations due to quantum statistics and final
state interactions and folded with the resolution of the NA49 apparatus. For
two specific models of non-statistical fluctuations in transverse momentum
limits are derived in terms of fluctuation amplitude. We show that a
significant part of the parameter space for a model of isospin fluctuations
predicted as a consequence of chiral symmetry restoration in a non-equilibrium
scenario is excluded by our measurement.Comment: 6 pages, 2 figures, submitted to Phys. Lett.
Demand-Side Management by Electric Utilities in Switzerland: Analyzing Its Impact on Residential Electricity Demand
Metabolic Versatility and Antibacterial Metabolite Biosynthesis Are Distinguishing Genomic Features of the Fire Blight Antagonist Pantoea vagans C9-1
Smits THM, Rezzonico F, Kamber T, et al. Metabolic Versatility and Antibacterial Metabolite Biosynthesis Are Distinguishing Genomic Features of the Fire Blight Antagonist Pantoea vagans C9-1. PLoS ONE. 2011;6(7): e22247.Background: Pantoea vagans is a commercialized biological control agent used against the pome fruit bacterial disease fire blight, caused by Erwinia amylovora. Compared to other biocontrol agents, relatively little is currently known regarding Pantoea genetics. Better understanding of antagonist mechanisms of action and ecological fitness is critical to improving efficacy. Principal Findings: Genome analysis indicated two major factors contribute to biocontrol activity: competition for limiting substrates and antibacterial metabolite production. Pathways for utilization of a broad diversity of sugars and acquisition of iron were identified. Metabolism of sorbitol by P. vagans C9-1 may be a major metabolic feature in biocontrol of fire blight. Biosynthetic genes for the antibacterial peptide pantocin A were found on a chromosomal 28-kb genomic island, and for dapdiamide E on the plasmid pPag2. There was no evidence of potential virulence factors that could enable an animal or phytopathogenic lifestyle and no indication of any genetic-based biosafety risk in the antagonist. Conclusions: Identifying key determinants contributing to disease suppression allows the development of procedures to follow their expression in planta and the genome sequence contributes to rationale risk assessment regarding the use of the biocontrol strain in agricultural systems
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