Deuteron and neutron structure functions and the effect of relativistic Fermi motion

The deep-inelastic deuteron structure function (SF) F₂^D in the covariant approach in the light-cone variables is considered. The neutron SF F₂ⁿ is extracted from the deuteron and proton experimental data taking into account the relativistic deuteron model and the parametrization of F₂ⁿ is obtained. The effect of the relativistic Fermi motion is estimated to be 6% at x0.7. The extracted neutron SF is used to verify the Gottfried sum rule. It is shown that the violation of the flavour symmetry of the sea can be large with increasing Q².     

Synthesis of Ozone in a Surface Barrier Discharge with a Plasma Electrode

The synthesis of ozone from oxygen in a cylindrical ozonizer operating under surface discharge conditions with a plasma electrode was studied. The conditions of ozone synthesis were optimized. The dependence of ozone concentration and specific energy consumption on gas pressure in the plasma electrode and on distance between the coils of a corona electrode was determined. The results were compared with data obtained with the use of classical surface barrier discharge.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 4, 2005, pp. 307–311.Original Russian Text Copyright © 2005 by Alemskaya, Lelevkin, Tokarev, Yudanov.     

Selective water sorbents for multiple applications, 3. CaCl2 solution confined in micro- and mesoporous silica gels: Pore size effect on the “solidification-melting” diagram

In this communication we present a low-temperature “solidification-melting” phase diagram for CaCl₂/H₂O solutions confined in KSK and KSM silica gels. At salt concentrations of 0–48 wt. %, the diagram has been found to lie below the diagram reported for the bulk system by 15–30°C. It shows a depression of the solution melting point due to its confinment to the pores. Several other peculiarities of melting and solidification in this system are also reported and discussed. Beside fundamental interest, the data obtained could be of importance in many commercial areas such as refrigeration, accumulation of low temperature heat, frost prevention in building materials,etc.     

Multiplicity dependence of <Emphasis Type="Italic">z</Emphasis> scaling for identified hadrons

The multiplicity dependence of inclusive spectra of identified hadrons (π, K, , K _S ⁰ , and Λ) produced in high-energy p and pp collisions is studied. Analysis of experimental data on high-p _T hadron cross sections obtained at the Tevatron and RHIC is performed in the framework of z scaling. Independence of the scaling function ψ(z) on the multiplicity density dN _ch/dη is established. The multiplicity density measured in nucleon-nucleon collisions reaches much higher values than the corresponding quantity [1/(0.5N _p)]dN _ch/dη obtained in heavy-ion collisions. Its influence on particle production reveals properties of self-similarity and fractality. The relation between the scaling variable z and thermodynamic quantities (“heat capacity” and “temperature”) of the medium associated with the produced inclusive particle is discussed. Search for z-scaling violation in p and pp collisions at very high multiplicities as an indication of new-physics phenomena is suggested. The text was submitted by the authors in English.     

Influence of cone algorithm parameters on efficiency and characteristics of reconstructed jets in p-p interactions at \sqrt s = 200 GeV

The influence of the cone algorithm parameters (E _cut, E _seed, R) on efficiency and characteristics of reconstructed jets in p-p collisions at the energy $\sqrt s $ = 200 GeV is studied. Event generation was carried out using the Monte Carlo code PYTHIA. The fraction of dijet event production as a function of transverse momentum of the hard process $\hat p_ \bot $ for different algorithm parameters is studied. The dependence of energy and parton direction reconstruction accuracy for dijet events and two leading jets in N-jet (N _Jet ≥ 2) events on the algorithm parameters is found. The results of jet modeling are compared with predictions obtained in the framework of z-scaling and experimental data obtained at RHIC. It is proved that the slope parameter of the scaling function is independent of the algorithm parameters in the transverse jet energy range E _T ^Jet = 25–60 GeV. It is shown that in the region E _T ^Jet < 25 GeV, strong dependence of invariant cross sections and the slope of the scaling function on the algorithm parameters is observed, and this dependence is enhanced with decreasing E _T ^Jet .     

Raman spectra of TlGaSe<Subscript>2</Subscript> single crystals

The results of the study of the Raman spectrum of TlGaSe₂ single crystals are presented. The ability of these layered crystals to cleave into plates with mirror faces, being a consequence of significant asymmetry of the chemical bond, makes them promising materials for photoelectric converters.     

<Emphasis Type="Italic">z</Emphasis>-Scaling and high-<Emphasis Type="Italic">p</Emphasis><Subscript><Emphasis Type="Italic">T</Emphasis></Subscript> particle production in hadron-hadron and hadron-nucleus collisions at high energies

The general features of particle production in hadron-hadron and hadron-nucleus collisions at high energy and transverse momentum using the concept of z-scaling are reviewed. z-Presentation of experimental data on the inclusive cross sections obtained at ISR, SPS, and Tevatron is presented and its properties are discussed. It is argued that the properties reflect the fundamental symmetries such as self-similarity, locality, and fractality. z-Scaling is used to predict particle yields in hadron-hadron and hadron-nucleus collisions at RHIC and LHC energies. The violation of z-scaling is considered as a signature of new physics phenomena.     

A Parameter-Dependent Symbolic Calculus for Pseudo-Differential Operators with Negative-Definite Symbols

Hoh's calculus for pseudo-differential operators with negative-definitesymbols is extended to the case of parameter-dependent symbols.Then this parameter-dependent calculus is applied to the studyof subordinate sub-Markovian semigroups.     

The Sura-EISCAT-WIND Experiments: Ionospheric Influence on the Response of a Decameter Interferometer with a Superlong Baseline

Results of the 1999 experiments on receiving radio-frequency signals from the SURA and EISCAT facilities on the WIND spacecraft at 5475 kHz are presented. Power and frequency distortions imposed by near-Earth plasmas on the response of SURA-EISCAT, an active decameter radio interferometer with a superlong baseline of 2000 km, are studied. Quasi-oscillatory variations in the intensity of the received radiation with a period of several tenths of a second and the corresponding maximum in the intensity fluctuation spectrum are observed during synchronized operation of the facilities under both quiet and perturbed geophysical conditions including the occurrence of mid-latitude F spread. Variations in the mean frequency of the spectral line both because of the motion of the spacecraft and the large-scale traveling ionospheric disturbances are detected. The obtained results are compared with the modern theoretical concept of propagation of short radio waves in a randomly irregular ionospheric plasma. The possibility to realize the limiting angular resolution of a ground-based decameter interferometer with a superlong baseline for observations of discrete space radio sources is discussed.