Synopsis We present the study of multiple electron processes produced by impact of proton beams on molecular targets from intermediate to high projectile impact energies. Transition probabilities and ...absolute cross sections were determined by using the Continuum Distorted Wave-Eikonal Initial State approximation. Results were compared with previous calculations and also with recent experimental data.
Spectral and kinetic properties of extrinsic crossluminescence (CL) in SrF2:Ba (1%) and CaF2:Ba (1%) are compared with those of intrinsic CL in BaF2 and are analyzed taking into account EXAFS data ...obtained at the Ba LIII edge and results of first-principles calculations. The CL decay time was revealed to be longer in SrF2:Ba and CaF2:Ba compared to BaF2. This fact contradicts the expected acceleration of luminescence decay which could result from an increased overlap of wave functions in solid solutions due to shortening of the Ba-F distance obtained in both EXAFS measurements and first-principles calculations. This discrepancy is explained by the effect of migration and subsequent non-radiative decay of the Ba (5p) core holes in BaF2 and by decreasing of the probability of optical transitions between Ba (5p) states and the valence band in SrF2:Ba and CaF2:Ba predicted by first-principles calculations.
•The crossluminescence kinetics in SrF2:Ba and CaF2:Ba is slower than in BaF2.•Ba2+ ions substitute for host Ca2+(Sr2+) ions in the on-center positions.•The nearest Ba-F distances in SrF2:Ba and CaF2:Ba are shorter than in BaF2.•EXAFS data and first-principles calculations of the local structure agree well.•First-principles calculations explain slower luminescence decay in solid solutions.
Preliminary results on the angular distributions of the vector
A
y
and tensor
A
yy
, A
xx
analyzing powers in dp elastic scattering at the energy of 800 MeV are presented. The measurements have been ...performed on Internal Target Station of the JINR Nuclotron using polarized deuteron beam from new source of polarized ions. The experimental data are compared with the preliminary calculations obtained within framework of relativistic multiple scattering approach.
Synopsis The Continuum Distorted Wave-Eikonal Initial State approximation for impact of H+ on H2O molecules is used to calculate absolute cross sections for multiple electron removal processes at ...intermediate and high collision energies. Resulting fragmentation patterns are also matter of study. Results are compared with previous calculations and available experimental data.
The current deuteron beam polarimetry at Nuclotron is provided by the Internal Target polarimeter based on the use of the asymmetry in dp-elastic scattering at large angles in the cms at 270 MeV. The ...upgraded deuteron beam polarimeter has been used to obtain the vector and tensor polarization during 2016 runs for the DSS experimental program. The polarimeter has been used also for tuning of the polarized ion source parameters for 6 different spin modes. The data analysis has been performed using developed software based on C++ language and ROOT5 library.
The interest of the present work is focused on theoretical calculations of single electron ionization, single electron capture and transfer-ionization reactions of He targets interacting with bare ...ion beams. In order to investigate all these processes, the corresponding transition probabilities are determined in the framework of the prior-version of the three-body Continuum Distorted Wave-Eikonal Initial State model (3B-CDW-EIS). A theoretical description using a trinomial probability analysis based on 3B-CDW-EIS is also presented to analyze its limitations for the studied reactions. The cases of He2+ and Li3+ projectiles are considered at intermediate and high collision energies. A unitarization procedure is employed to avoid transition probabilities larger than one at intermediate velocities.
At present, actual problem is to measure the flow of liquid and gaseous hydrocarbons without separation. One of the problems associated with the definition of the parameters of motion multiphase ...mixtures, is to determine the parameters flows liquid and gaseous hydrocarbons of multiphase flow for multiphase meters that make measurement without separation of the hydrocarbon mixture into individual phases and fractions. The use of such flow measuring devices can greatly simplify the process of measuring the flow of hydrocarbon mixture to make it more responsive (including the use for mobile multiphase flow and compact subsea devices) and more cost effective.
The object of this study is multiphase flowmeter flow path and the processes occurring along the axis of the flowmeter. the Venturi tube, designed to measure the volumetric rate flowing therein medium using differential pressure, is considered as a measuring means. Based on the results of numerical solution of equations for steady turbulent flow of compressible multiphase flow the accuracy of measurement of pressure along the axis measuring part of the Venturi tube and the pressure unit is estimated, and also the flow of multiphase medium is considered.
The deuteron beam vector polarization was obtained at the Nuclotron Internal Target Station using proton-proton quasielastic scattering on the polyethylene target at the beam energies of 200, 500, ...550, and 650 MeV/nucleon. The proton beam polarization was obtained at the beam energy of 500 MeV. The selection of useful events was performed using the time and amplitude information from the scintillation counters and the subtraction of the carbon background, both for the deuteron and proton beams.
The first experimental results on the dynamics of a plasma cloud produced by a miniature coaxial gun in a magnetized background plasma have been reported. The record dimension of the plasma in the ...Krot device, which is more than 1 m across a magnetic field, has allowed the first implementation of the regime of “unbounded” background plasma, which is optimal for the simulation of astro- and geophysical phenomena. In the sub-Alfvénic regime of cloud expansion, a set of characteristic effects has been demonstrated, including the formation of a diamagnetic cavity, deceleration of ions of the cloud by the background plasma, and development of high-frequency instability at the edge of the cloud.
Dp
breakup reaction is investigated in the energy range 300-500 MeV at the Internal Target of the Nuclotron using unpolarized and polarized beams by DSS collaboration. The goal of the study is to ...obtain information about nucleon-nucleon correlations at short distances, non-nucleonic degrees of freedom and relativistic effects. A part of the breakup data at 300 MeV and 400 MeV has been obtained in kinematics where relativistic effects would have a significant contribution.
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