Sensitivity to the pion-nucleon coupling constant in partial-wave analyses of elastic pi-N and NN scattering and pion photoproduction

We summarize results obtained in our studies of the pion-nucleon coupling constant. Several different techniques have been applied to pi-N and NN elastic scattering data, and the existing database for single-pion photoproduction. The most reliable determination comes from pi-N elastic scattering. The sensitivity in this reaction was found to be greater, by at least a factor of 3, when compared with analyses of NN elastic scattering or single-pion photoproduction.Comment: 10 pages, 1 figure. Talk given at the Uppsala workshop on the pion-nucleon coupling constan

Phase field modelling of grain boundary premelting using obstacle potentials

We investigate the multi-order parameter phase field model of Steinbach and Pezzolla [I. Steinbach, F. Pezzolla, A generalized field method for multiphase transformations using interface fields, Physica D 134 (1999) 385-393] concerning its ability to describe grain boundary premelting. For a single order parameter situation solid-melt interfaces are always attractive, which allows to have (unstable) equilibrium solid-melt-solid coexistence above the bulk melting point. The temperature dependent melt layer thickness and the disjoining potential, which describe the interface interaction, are affected by the choice of the thermal coupling function and the measure to define the amount of the liquid phase. Due to the strictly finite interface thickness also the interaction range is finite. For a multi-order parameter model we find either purely attractive or purely repulsive finite-ranged interactions. The premelting transition is then directly linked to the ratio of the grain boundary and solid-melt interfacial energy.Comment: 12 page

Fog detection using airport radar

Fog is a significant factor affecting the Air Traffic Control (ATC). Significant limitations of the airport capacity are due to fog that causes the reduction of the visibility (Runway Visual Range, RVR). Today METAR (Meteorological Aviation Report) and forecasts TAF (Terminal Aerodrome Forecast) are only available to estimate the visibility variations, but not to estimate the RVR. Scope of this paper is to evaluate the performance of airport radar sensors to detect the fog

Quality of Government and Well-being: An Empirical Analysis of 158 European Regions

The aim of the study is twofold: on the one hand, it assesses the association between well-being and the quality of government, on the other it evaluates the impact exerted on the same well-being by the different components into which the quality of government can be broken down. The analysis is conducted at the regional level. A composite indicator derived from OECD data on regional well-being is used to assess its association with the quality of government. The latter is measured using the European Quality of Government Survey Index (EQI) data. The EQI breaks down the quality of government into three key elements: the impartiality of administration, the quality of services provided and the degree of corruption. The association between well-being and quality of government is verified considering, at first, the EQI index as a whole, being the product of the three different components, and then separately considering its key elements.The results confirmed the existence of a strong positive association between well-being and the overall quality of government, as between the former and the single components of the EQI index. Furthermore, the same association is observed when the assessment is made on the whole sample, but also when subsamples are made, considering the geographical macro-area to which the regions belong

Heranca da tolerancia de melancia aos virus do mosaico amarelo da abobrinha-de-moita e do mosaico da melancia-2.

A heranca da tolerancia da introducao de melancia BT-8501 aos virus do mosaico amarelo da abobrinha-de-moita (ZYMV) e do mosaico da melancia-2 (WMV-2) foi determinada atraves da inoculacao mecanica de plantas das geracoes parentais, F1, F2 e retrocruzamento para os progenitores "Perola" (sensivel) e BT-8501 (tolerante). A heranca da tolerancia de BT-8501 ao ZYMV e WMV-2, confirmada com testes de progenies, demonstrou ser devida a dois pares de genes recessivos com modificadores tambem recessivos, que parecem controlar a tolerancia a ambas as viroses

Determination of the Pion-Nucleon Coupling Constant in the VPI/GW Pion-Nucleon Elastic Scattering Partial Wave and Dispersion Relation Analyis

Our extraction of the pion-nucleon coupling constant from \pi p elastic scattering data is outlined. A partial wave analysis (T_{\pi} < 2100 MeV) is performed simultaneously with a fixed-t dispersion relation analysis (T_{\pi} < 800 MeV). The \pi NN coupling constant g^2/4\pi is searched to find the best fit. The result 13.73 \pm 0.01 \pm 0.07 (first error statistical, second systematic) is found to be insensitive to database changes and Coulomb barrier corrections. This value satisfies important elements of low energy QCD like the Goldberger-Treiman discrepancy, the Dashen-Weinstein sum rule, and chiral perturbation theory predictions of threshold pion photoproduction.Comment: Proceedings of the Pion-Nucleon Coupling Constant Workshop, Uppsala, Sweden, June 7-8 1999 To be published by Physica Scripta 20 pages, 7 figure