A survey of the effect of grooved runway operations on the wear of commercial airline tires

Effect of grooved runway operations on wear of commercial airline tire

Hamiltonian Reduction of SL(2)SL(2)-theories at the Level of Correlators

Since the work of Bershadsky and Ooguri and Feigin and Frenkel it is well known that correlators of $SL(2)$ current algebra for admissible representations should reduce to correlators for conformal minimal models. A precise proposal for this relation has been given at the level of correlators: When $SL(2)$ primary fields are expressed as $\phi_j(z_n,x_n)$ with $x_n$ being a variable to keep track of the $SL(2)$ representation multiplet (possibly infinitely dimensional for admissible representations), then the minimal model correlator is supposed to be obtained simply by putting all $x_n=z_n$. Although strong support for this has been presented, to the best of our understanding a direct, simple proof seems to be missing so in this paper we present one based on the free field Wakimoto construction and our previous study of that in the present context. We further verify that the explicit $SL(2)$ correlators we have published in a recent preprint reduce in the above way, up to a constant which we also calculate. We further discuss the relation to more standard formulations of hamiltonian reduction.Comment: 13 pages, LaTe

Ten polymorphic microsatellite primers in the tropical tree caimito, Chrysophyllum cainito (Sapotaceae).

UnlabelledPremise of the studyWe developed microsatellite primers for the tropical tree Chrysophyllum cainito (Sapotaceae) to determine the native range of the species, investigate the origin of cultivated populations, and examine the partitioning of genetic diversity in wild and cultivated populations. •Methods and resultsWe developed 10 polymorphic primers from C. cainito genomic DNA libraries enriched for di-, tri-, and tetranucleotide repeat motifs. The loci amplified were polymorphic in samples collected from Jamaica and Panama. The number of alleles per locus ranged from two to 10 and three to 12, while observed heterozygosities ranged from 0.074 to 0.704 and 0.407 to 0.852 in Jamaica and Panama, respectively. •ConclusionsThe microsatellite primers will be useful in future population genetic studies as well as those aimed at understanding the geographic origin(s) of wild and cultivated populations

Directed flow, a signal for the phase transition in Relativistic Nuclear Collisions?

The sign change of the slope of the directed flow of baryons has been predicted as a signal for a first order phase transition within fluid dynamical calculations. Recently, the directed flow of identified particles has been measured by the STAR collaboration in the beam energy scan (BES) program. In this article, we examine the collision energy dependence of directed flow $v_1$ in fluid dynamical model descriptions of heavy ion collisions for $\sqrt{s_{NN}}=3-20$ GeV. The first step is to reproduce the existing predictions within pure fluid dynamical calculations. As a second step we investigate the influence of the order of the phase transition on the anisotropic flow within a state-of-the-art hybrid approach that describes other global observables reasonably well. We find that, in the hybrid approach, there seems to be no sensitivity of the directed flow on the equation of state and in particular on the existence of a first order phase transition. In addition, we explore more subtle sensitivities like e.g. the Cooper-Frye transition criterion and discuss how momentum conservation and the definition of the event plane affects the results. At this point, none of our calculations matches qualitatively the behavior of the STAR data, the values of the slopes are always larger than in the data.Comment: 7 pages, 7 figure

Anomalous Chiral Action from the Path-Integral

By generalizing the Fujikawa approach, we show in the path-integral formalism: (1) how the infinitesimal variation of the fermion measure can be integrated to obtain the full anomalous chiral action; (2) how the action derived in this way can be identified as the Chern-Simons term in five dimensions, if the anomaly is consistent; (3) how the regularization can be carried out, so as to lead to the consistent anomaly and not to the covariant anomaly. Our method uses Schwinger's ``proper-time'' representation of the Green's function and the gauge invariant point-splitting technique. We find that the consistency requirement and the point-splitting technique allow both an anomalous and a non-anomalous action. In the end, the nature of the vacuum determines whether we have an anomalous theory, or, a non-anomalous theoryComment: 28 page

Hadronic and electromagnetic probes of hot and dense matter in a Boltzmann+Hydrodynamics model of relativistic nuclear collisions

We present recent results on bulk observables and electromagnetic probes obtained using a hybrid approach based on the Ultrarelativistic Quantum Molecular Dynamics transport model with an intermediate hydrodynamic stage for the description of heavy-ion collisions at AGS, SPS and RHIC energies. After briefly reviewing the main results for particle multiplicities, elliptic flow, transverse momentum and rapidity spectra, we focus on photon and dilepton emission from hot and dense hadronic matter.Comment: To appear in the proceedings of WISH 2010: International Workshop on Interplay between Soft and Hard interactions in particle production at ultrarelativistic energies, Catania, Italy, 8-10 September 201