Forward observables at RHIC, the Tevatron run II and the LHC

We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude (rho parameter) for present and future pp and pbar p colliders, and on total cross sections for gamma p -> hadrons at cosmic-ray energies and for gamma gamma -> hadrons up to sqrt(s)=1 TeV. These predictions are based on a study of many possible analytic parametrisations and invoke the current hadronic dataset at t=0. The uncertainties on total cross sections, including the systematic theoretical errors, reach 1% at RHIC, 3% at the Tevatron, and 10% at the LHC, whereas those on the rho parameter are respectively 10%, 17%, and 26%.Comment: 11 pages, 2 figures, LaTeX, presented at the Second International "Cetraro" Workshop & NATO Advanced Research Workshop "Diffraction 2002", Alushta, Crimea, Ukraine, August 31 - September 6, 200

Effect of seed inoculation and foliar fertilizing on structure of soybean yield and yield structure in Western Polissya of Ukraine

Growing soybeans requires adjustment of micronutrient nutrition on poorly fertile soils. Foliar fertilization can overcome the deficiency of micronutrients in plants in the most important period. Three factorial field experiment to study foliar fertilization with complex micronutrients, seed inoculation by Bradyrhizobium japonicum in two soybean varieties (Kassidy and ES Mentor) was conducted. Foliar fertilization with Quantum oil and WUXAL Oilseed significantly increased certain elements in soybean yield structure. Fertilizer WUXAL Oilseed with a higher concentration of Mo, Mn and B more effectively increased the number of pods and seeds from the plant and formed a higher yield in soybeans. Foliar fertilization with WUXAL Oilseed and Quantum oil increased seed yield to 3.00 t ha-1 and 2.94 t ha-1 , respectively in regard to variant without fertilizing, where yield was 2.71 t ha-1 . Variety Kassidy had greater number of pods and seeds, seed weight in comparison to foliar fertilizing ES Mentor. Seed inoculation gaves a stable increase in yield under different foliar fertilizations in varieties Kassidy and ES Mentor

On performance of thin-film meso-structured perovskite solar cell through experimental analysis and device simulation

In the last few years there is an unprecedented progress in the increase of the power conversion efficiency of perovskite solar cells. Evidently, further advances of the efficiency of these devices will depend on the constraints imposed by the optical and electronic properties of their constituents. Quite apparently that during the manufacturing process of a solar cell, there is an inevitable variation in the thicknesses of various functional layers, which affects the optoelectronic characteristics of the final sample. In this work a possible strategy of the analysis of the solar cell performance is suggested, based on statistically averaging procedure of experimental data. We present a case study, in which the optoelectronic properties of the meso-structured perovskite solar cell (with a mesoporous TiO$_2$ layer) are analysed within the method providing a deeper understanding of the device operation. This method enables an assessment of the overall quality of the device, pointing pathways towards the maximum efficiency design of a perovskite solar cell by material properties tuning.Comment: 13 pages, 10 figure

Photoproduction of vector mesons in the Soft Dipole Pomeron model

Exclusive photoproduction of all vector mesons by real and virtual photons is considered in the Soft Dipole Pomeron model. It is emphasized that being the Pomeron in this model a double Regge pole with intercept equal to one, we are led to rising cross-sections but the unitarity bounds are not violated. It is shown that all available data for rho, omega, phi, J/psi and Upsilon in the region of energies 1.7 <= W <= 250 GeV and photon virtualities 0 <= Q^2 <= 35 GeV^2, including the differential cross-sections in the region of transfer momenta 0 <= |t| <= 1.6 GeV^2, are well described by the model.Comment: 17 pages, 19 figure

Benchmarks for the Forward Observables at RHIC, the Tevatron-run II and the LHC

We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude (rho parameter) for present and future pp and pbar p colliders, and on total cross sections for gamma p -> hadrons at cosmic-ray energies and for gamma gamma-> hadrons up to sqrt{s}=1 TeV. These predictions are based on an extensive study of possible analytic parametrisations invoking the biggest hadronic dataset available at t=0. The uncertainties on total cross sections, including the systematic errors due to contradictory data points from FNAL, can reach 1.9% at RHIC, 3.1% at the Tevatron, and 4.8% at the LHC, whereas those on the rho parameter are respectively 5.4%, 5.2%, and 5.4%.Comment: 11 pages, 2 figures, 4 tables, RevTeX

The soft and the hard pomerons in hadron elastic scattering at small t

We consider simple-pole descriptions of soft elastic scattering for pp, pbar p, pi+ p, pi- p, K+ p and K- p. We work at t and s small enough for rescatterings to be neglected, and allow for the presence of a hard pomeron. After building and discussing an exhaustive dataset, we show that simple poles provide an excellent description of the data in the region - 0.5 GeV^2 < t < -0.1 GeV^2, 6 GeV<sqrt(s)< 63 GeV. We show that new form factors have to be used, and get information on the trajectories of the soft and hard pomerons.Comment: 27 pages, 9 figures, LaTeX. A few typos fixed, and references correcte

On the rise of proton-proton cross-sections at high energies

The rise of the total, elastic and inelastic hadronic cross sections at high energies is investigated by means of an analytical parametrization, with the exponent of the leading logarithm contribution as a free fit parameter. Using derivative dispersion relations with one subtraction, two different fits to proton-proton and antiproton-proton total cross section and rho parameter data are developed, reproducing well the experimental information in the energy region 5 GeV - 7 TeV. The parametrization for the total cross sections is then extended to fit the elastic (integrated) cross section data in the same energy region, with satisfactory results. From these empirical results we extract the energy dependence of several physical quantities: inelastic cross section, ratios elastic/total, inelastic/total cross sections, ratio total-cross-section/elastic-slope, elastic slope and optical point. All data, fitted and predicted, are quite well described. We find a statistically consistent solution indicating: (1) an increase of the hadronic cross sections with the energy faster than the log-squared bound by Froissart and Martin; (2) asymptotic limits 1/3 and 2/3 for the ratios elastic/total and inelastic/total cross sections, respectively, a result in agreement with unitarity. These indications corroborate recent theoretical arguments by Ya. I. Azimov on the rise of the total cross section.Comment: 35 pages, 12 figures, discussions improved with further clarifications, references added and updated, one note added, results and conclusions unchanged. Version to be published in J. Phys. G: Nucl. Part. Phy

Phase diagram of superfluid 3He in "nematically ordered" aerogel

Results of experiments with liquid 3He immersed in a new type of aerogel are described. This aerogel consists of Al2O3 strands which are nearly parallel to each other, so we call it as a "nematically ordered" aerogel. At all used pressures a superfluid transition was observed and a superfluid phase diagram was measured. Possible structures of the observed superfluid phases are discussed.Comment: 6 pages, 8 figures. Submitted to Pis'ma v ZhETF (JETP Letters