29 research outputs found
Perturbative Effects in the Form Factor \gamma\gamma^*\to \pi and Extraction of the Pion Wave Function from CLEO Data
We study the pion form factor F^{\pi \gamma\gamma^*}(Q^2) in the light-cone
sum rule approach, accounting for radiative corrections and higher twist
effects.
Comparing the results to the CLEO experimental data on F^{\pi
\gamma\gamma^*}(Q^2), we extract the the pion distribution amplitude of
twist-2. The deviation of the distribution amplitude from the asymptotic one is
small and is estimated to be a_2(\mu) = 0.12 \pm 0.03 at \mu=2.4 GeV, in the
model with one non-asymptotic term. The ansatz with two non-asymptotic terms
gives some region of a_2 and a_4, which is consistent with the asymptotic
distribution amplitude, but does not agree with some old models.Comment: 21 pages, LaTeX, 7 eps figures; (v2): Phys. Rev. D versio
A subfamília Faboideae (Fabaceae Lindl.) no Parque Estadual do Guartelá, Paraná, Brasil
Results analysis of agricultural organizations subsidy
The article presents some issues of the methodology of the study of state support for agricultural production in the aspect of efficiency. The dynamic series of profitability for certain types of products sold by agricultural organizations with and without budget subsidies are used as source data. First, a preliminary analysis and pairwise comparison of the series using nonparametric methods is carried out. Further, in order to use complete information on all the data, the methods of reduction to three variables are applied. In order to compare different methods, the principal component method and autoencoding using a neural network were used. The transformed data was also compared with and without subsidies. Conclusions and practical recommendations on the results obtained, as well as directions for the development of scientific research, are formulated