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Yu. M. Shabelski

Publications and source records attributed to Yu. M. Shabelski.

At least 37 records · Page 2Linked to original sources
arXiv2015

Midrapidity hyperon production in pp and pA collisions from low to LHC energies

The experimental data on p, Lambda, Xi-, Omega-, baryons and the corresponding antibaryons spectra obtained by different collaborations are compared with the results of the calculations performed into the frame of the Quark-Gluon String Model. The contribution of String Junction diffusion and the inelastic screening corrections are accounted for in the theoretical calculations. The predictions of the Quark-Gluon String Model both for pp and pA collisions are extended up to the LHC energies.

hep-ph↗
arXiv2015

Diffractive dissociation in high energy pp collisions in Additive Quark Model

High energy (CERN SPS and LHC) $pp$ ($p\bar p$) scattering is treated in the framework of Additive Quark Model together with Pomeron exchange theory. The reasonable agreement with experimental data is achieved both for the elastic scattering and for the diffractive dissociation with natural parameters for the strong matter distribution inside proton.

hep-ph↗
arXiv2014

High Energy Elastic pp Scattering in Additive Quark Model

High energy $pp$ and $p\bar p$ elastic scattering is treated in the framework of Additive Quark Model. The reasonable agreement with experimental data is achieved with the natural parameters for the strong matter distribution inside proton.

hep-ph↗
arXiv2014

Pseudoscalar meson photoproduction on nucleon target

We consider the photoproduction of secondary mesons in the framework of the Quark-Gluon String model. At relatively low energies, not only cylindrical, but also planar diagrams have to be accounted for. To estimate the significant contribution of planar diagrams in gamma-p collisions at rather low energies, we have used the expression obtained from the corresponding phenomenological expression for pi-p collisions. The results obtained by the model are compared to the existing SLAC experimental data. The model predictions for light meson production at HERMES energies are also presented.

hep-ph↗
arXiv2014

Hadroproduction of var(phi)-mesons in the Quark-Gluon String model

We consider the experimental data on var(phi)-meson production in hadron-nucleon collisions for a wide energy region. The Quark-Gluon String Model quantitatively describes the spectra of secondary var(phi), as well as the ratios of var(phi)/pi^- and var(phi)/K^- production cross sections.

hep-ph↗
arXiv2014

Selection Trigger for Rare Quark-Gluon Plasma Formation Events

We consider the experimental ratios of multistrange to strange antibaryon production and compare them to the standard Quark-Gluon String Model predictions. The significant differences between the experimental bar(Xi)+/bar(Lambda) and, especially, bar(Omega)+/bar(Lambda) values and model predictions can be interpreted as the signal of the existence of an additional source of multistrange antibaryon production. The possible connection of this additional source with Quark-Gluon Plasma (QGP) formation can turn the bar(Omega)+ production into a good QGP signature.

hep-ph↗
arXiv2013

Proton and Lambda-Hyperon Production in Nucleus-Nucleus Collisions

The experimental data on net proton and net Lambda-hyperon spectra obtained by the NA35 Collaboration, as well as the inclusive densities of Lambda and bar-Lambda obtained by NA49, NA57, and STAR collaborations, are compared with the predictions of the Quark-Gluon String Model. The contributions of String Junction diffusion, interactions with nuclear clusters, and the inelastic screening corrections are accounted for. The level of numerical agreement of the calculations with the experimental data is of about 20-30%. The predictions for LHC are also presented.

hep-ph↗
arXiv2012

Production of secondaries in soft p+pb collisions at LHC

We calculate the inclusive spectra of secondaries produced in soft (minimum bias) p+Pb collisions in the framework of Quark-Gluon String Model at LHC energy, and by taking into account the inelastic screening corrections (percolation effects). The role of these effects is expected to be very large at very high energies, and they should decrease the spectra about 3 times in the midrapidity region and increase them about 2 times in the fragmentation region at the energy of LHC.

hep-ph↗
arXiv2012

Feynman scaling violation on baryon spectra in pp collisions at LHC and cosmic ray energies

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of baryon charge diffusion in rapidity space. Such a diffusion should decrease the baryon charge in the fragmentation region and translate into the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. Another numerically more significant reason for the Feynman scaling violation comes from the fact that the average number of cutted Pomerons increases with initial energy. We present the quantitative predictions of the Quark-Gluon String Model (QGSM) for the Feynman scaling violation at LHC energies and at even higher energies that can be important for cosmic ray physics.

hep-ph↗
arXiv2012

Elastic pp Scattering at LHC Energies

We consider the first LHC data for elastic pp scattering in the framework of Regge theory with multiple Pomeron exchanges. The simplest eikonal approach allows one to describe differential elastic cross sections at LHC, as well as pp and $\bar{p}p$ scattering at lower collider energies, on a reasonable level.

hep-ph↗
arXiv2011

Feynman scaling violation due to baryon number diffusion in rapidity space

A significant asymmetry in baryon/antibaryon yields in the central region of high energy collisions is observed when the initial state has non-zero baryon charge. This asymmetry is connected with the possibility of a baryon charge diffusion in rapidity space. Evidently, such a diffusion should decrease the baryon charge in the fragmentation region leading to the corresponding decrease of the multiplicity of leading baryons. As a result, a new mechanism for Feynman scaling violation in the fragmentation region is obtained. We present the quantitative predictions for the Feynman scaling violation at LHC energies and even at highier energies that can be important for cosmic ray physics.

hep-ph↗
arXiv2011

Particle Production in the Central Region at LHC Energies

We consider the first LHC data for pp collisions in the framework of Regge phenomenology, and the Quark-Gluon String Model, and we present the corresponding predictions for both the integral cross sections and the inclusive densities of secondaries, that are determined by Pomeron exchange. All parameters were fixed long time ago for the description of the data at fixed target energies. The first measurements of the total inelastic cross section by ATLAS and CMS Collaborations are in agreement with our calculations. Also the inclusive densities measured in the central region are in agreement with our theoretical predictions on the accuracy level of about 10-15%.

hep-ph↗
arXiv2010

Pomeron and Odderon Contributions at LHC Energies

We consider the first LHC data for pp collisions in the framework of Regge theory. The integral cross sections and inclusive densities of secondaries are determined by the Pomeron exchange, and we present the corresponding predictions for them. The first measurements of inclusive densities in midrapidity region are in agreement with these predictions. The possible contribution of Odderon (Reggeon with alpha(Odd)(0) ~ 1 and negative signature) exchange to the differences in the inclusive spectra of particle and antiparticle in the central region could be significant at LHC energies. The first data of ALICE Collaboration are consistent with a very small Odderon contribution. Probably, further LHC data will definitely settle the question of the Odderon existence.

hep-ph↗
arXiv2010

Production of Strange Secondaries in High Energy Sigma(-)A Collisions

We describe the WA89 Collaboration experimental data on Lambda, Sigma(-), Sigma(+), Xi(-), and Omega(-) baryons, and bar(Lambda) and bar(Xi(+)) antibaryons production in Sigma(-) collisions with C and Cu targets at 345 GeV/c (sqrt(s_(Sigma N)) ~ 25.5 GeV) in the frame of the Quark-Gluon String Model. How the theoretical results compare to the experimental data is discussed. Finally, some relations among the values of the model parameters obtained with the help of quark combinatorics are presented.

hep-ph↗
arXiv2009

Heavy Flavour Production in pp and Heavy Ion Collisions in QCD Up to LHC Energies

Charm production in pp collisions is considered in the framework of perturbative QCD. The values of two parameters, the charm quark mass $m_c$ and the QCD scale mu^2, are determined from the comparison of the theoretical calculations with experimental data. The RHIC data on charm and beauty production are compared with the k_T-factorization approach predictions and with standard NLO QCD. The calculated results underestimate the STAR Collaboration data. The role of possible nuclear effects is discussed. The predictions for LHC energies are also given.

hep-ph↗
arXiv2009

Nuclear Radii Calculations in Various Theoretical Approaches for Nucleus-Nucleus Interactions

The information about sizes and nuclear density distributions in unstable (radioactive) nuclei is usually extracted from the data on interaction of radioactive nuclear beams with a nuclear target. We show that in the case of nucleus-nucleus collisions the values of the parameters depend rather strongly on the considered theoretical approach and on the assumption about the parametrization of the nuclear density distribution. The obtained values of root-mean-square radii (R_{rms}) for stable nuclei with atomic weights A = 12-40 vary by approximately 0.1 fm when calculated in the optical approximation, in the rigid target approximation, and using the exact expression of Glauber Theory. We present several examples of R_{rms} radii calculations using these three theoretical approaches and compare these results with the data obtained from electron-nucleus scattering.

nucl-th↗
arXiv2009

Odderon Effects in pp Collisions: Predictions for LHC Energies

We consider the possible contribution of Odderon (Reggeon with alpha_(Odd)(0) similar to 1 and negative signature) exchange to the differences in the total cross sections of particle and antiparticle, to the ratios of real/imaginary parts of the elastic pp amplitude, and to the differences in the inclusive spectra of particle and antiparticle in the central region. The experimental differences in total cross sections of particle and antiparticle are compatible with the existence of the Odderon component but such a large Odderon contribution seems to be inconsistent with the values of Re/Im ratios. In the case of inclusive particle and antiparticle production the current energies and/or accuracy of the experimental data don't allow a clear conclusion. It is expected that the LHC will finally solve the question of the Odderon existence.

hep-ph↗