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O. B. Abdinov

Publications and source records attributed to O. B. Abdinov.

13 recordsLinked to original sources
arXiv2012

Nuclear Transparency Effect in the Strongly Interacting Matter

We discuss that the results of study of the nuclear transparency effect in nuclear-nuclear collisions at relativistic and ultrarelativistic energies could help to extract the information on new phases of the strongly interacting matter as well as the QCD critical point. The results could provide further confirmation of the existence of the "horn" effect which had initially been obtained for the ratio of average values of K+ to pi+ -mesons' multiplicity as a function of the initial energies in the NA49 SPS CERN experiment. To observe the "horn" as a function of centrality, the new more enriched experimental data are required. The data which are expected from NICA/MPD JINR and CBM GSI setups could fulfill the requirement.

nucl-ex↗
arXiv2010

Electric charge quantization in SU(3)_c X SU(3)_L X U(1)_X model

Basing on the general photon eigenstate and anomaly cancellation, it is shown that the electric charge quantization in SU(3)_c X SU(3)_L X U(1)_X model with exotic particles can be obtained independently on parameters alpha and betta. The fixation of hypercharges of fermions fields by the Higgs fields and dependence of the electric charges quantization conditions from the hypercharges of Higgs fields leads to the fact that the electric charge in the considered model can be quantized and fixed only in the presence of Higgs fields. In addition, we have shown that in the considered model the classical constraints following from the Yukawa interactions are equivalent to the conditions following from the parity invariance of electromagnetic interaction. The most general expressions for the gauge bosons masses, eigenstates of neutral fields and the interactions of leptons and quarks with gauge bosons have been derived in the arbitrary case

hep-ph↗
arXiv2008

Electric Charge Quantization in Standard Model

In the framework of Standard Model for the arbitrary values of Higgs and fermions fields hypercharges, taking into account parity invariance of electromagnetic interaction, expressions for the fermions charges, testifying the electric charge quantization are obtained. From the chiral anomalies cancellation condition within one family of leptons and quarks, numerical values of fermions charges, coinciding with standard values of charges have been obtained.

hep-ph↗
arXiv2007

Formation of the intermediate baryon systems in hadron-nuclear and nuclear-nuclear interactions

The centrality experiments indicate regime change and saturation in the behavior of some characteristics of the secondary particles emitted in hadron-nuclear and nuclear-nuclear interactions at high energies. The phenomenon has a critical character. The simple models do not explain the effect. We suppose that the responsible mechanism to explain the phenomenon could be the formation and decay of the intermediate baryon systems. Such systems could be formed as a result of nucleon percolation in compressed baryonic matter. Formation of big percolation cluster may change the properties of the medium, e.g., it could lead to the changing its transparency. This could be used to get a signal of the intermediate baryonic system formation. We consider two signals to identify the formation of the intermediate baryon systems: the critical changing of transparency of the strongly interacting matter and the enhancement of light nuclei production with increase in centrality.

nucl-ex↗
arXiv2007

Multiplicity and angular distribution of particles emitted in relativistic nuclear-nuclear interactions

We discuss the experimental results on the behavior of the average multiplicities and angular distributions of slow particles emitted in hadron-nuclear and nuclear-nuclear interactions at relativistic energies as a function of the centrality of collisions. It is observed that by increasing the mass of the projectiles the angular distributions of slow particles change and the structure which was demonstrated in the case of pi-mesons, protons and light nuclear projectiles, almost disappears. During the interaction of the heavier projectile with nuclear target, the number of secondary interactions as well as number of nucleon-nucleon elastic scattering and re-scattering events increases. We suggest to restore this information using the heavy ion generators taking into account the multiplicity distributions. Because our investigations show that the formation of the percolation cluster sufficiently influences the behaviour of the average multiplicity of the slow particles emitted in these interactions.

nucl-ex↗
arXiv2005

Search for Signal on Percolation Cluster Formation in Nucleus-Nucleus Collisions at Relativistic Energies

The appearance of the strongly interacting matter mixed phase (MP)has been suggested to consider to understand qualitatively the regime change existence in the behavior of some centrality depending characteristics of events. The MP has been predicted by QCD for the temperatures around the critical temperature Tc and could be formed as a result of nucleon percolation in the density nuclear matter. Our main goal is to get a new experimental confirmation of the percolation cluster formation as an accompanying effect of the MP formation. To reach the goal, the experimental data on Kr+Em - reaction at 0.95 GeV/nuc and Au+Em - reaction at 10.6 GeV/nucl. with a number of target fragments N_h > 8, have been analyzed. The behavior of the distributions of the target and the projectile fragments has been studied. The experimental data have been compared of the data coming from the cascade-evaporation model. We can conclude that: -- the centrality of the collision could be defined as a number of the target g-fragments in Kr+Em reactions at energies 0.95 A GeV/nucl and as a number of projectile F-fragments with Z>=1 in Au + Em reactions at energies 10.6 A GeV/nucl; -- the formation of the percolation cluster sufficiently influences the characteristics of nuclear fragments; -- there are points of the regime changes in the behavior of some characteristics of $s$-particles as a function of centrality which could be qualitatively understood as a result of the big percolation cluster formation.

hep-ex↗
arXiv2001

Transition to the region of central collisions and critical phenomena

The experimental results on the relation between the processes of total disintegration of nuclei (or the cases with central collisions) and the critical phenomena which can occur in the region of high degree of nuclear disintegration or of collision centrality are discussed.

hep-ex↗
arXiv2001

Transition to the region of central collisions

The experimental results on the behaviour of the characteristics of secondary particles depending on the disintegration degree of nuclei are used to determine the region of central collisions. It was therefore possible that : - the correlation between the prosesses of total disintegration of nuclei and the central collisions of nuclei had been shown; - the existence of the regime change points in the behaviour of the considered characteristics of secondary particles depending on the disintegration degree of nuclei had been observed in the other earlier experiments as well. The number of all protons in 12CC-interactions at the momentum of 4.2 A GeV/c obtained from the 2-m propane bubble chamber exposed at the Dubna machine is considered as a disintegration degree of nuclei. The experimental results demonstrate that there are cases corresponding to the critical phenomena among the events with the central collisions of nuclei. For 12CC-interaction the behaviour of the number of the events, depending on Q also depends on the number of fragments and has a two-steps form. This result could be explained by the existence of nuclear clusters. The experimental results on the relation between the number of events, the angular distributions of protons and full number of protons are presented for 12CC-interactions at the momentum of 4.2 A GeV/c. The influence of nuclear fragmentation process on the results is also considered. The obtained results confirm the assumption that there exist the critical phenomena among the central collisions and it is necessary to use a percolation approach for the full description of the central collisions.

hep-ex↗
arXiv2000

Investigation of an angular distribution of protons in peripheral and central nucleus-nucleus collisions at the momentum of 4.2 A GeV/c

The experimental results on the relation between the number of events, the angular distributions of protons and full number of protons are presented for ${}^{12}CC$-interactions at the momentum of 4.2 A GeV/c. The influence of nuclear fragmentation process on the results is also considered. The obtai- ned results confirm the assumption that there exist the critical phenomena among the central collisions and it is necessary to use a percolation approa- ch for the full description of the central collisions.

hep-ex↗
arXiv1999

Centrality of collisions and total disintegration of nuclei

The interrelation of the processes of total disintegration of nuclei with the processes, characterized by the "centrality" of collisions and a minimum flow of energy of secondary particles emitted at a zero angle in pC, dC, 4HeC and 12CC interactions, is investigated at 4.2 A GeV/c . The events with total disintegration of nuclei are characterized by a high degree "centrality" of collisions and similar to the events having a minimum flow of energy of particles emitted at a zero angle.

hep-ex↗
arXiv1998

Inverses of slopes of invariant inclusive spectra of emitted protons and pi minus mesons in 4HeC and 12CC interactions with the total disintegration of nuclei

The ideas that extreme states of nuclear matter arise in events with total dis- integration of nuclei (TDN) and as these states arise, the properties of events qualitatively change with the number of protons emitted from the nucleus Q,star- ting from its certain boundary numbe Q*,are used in this paper for the experi- mentally search for extreme states of nuclear matter. For realization of these ideas, the invariant inclusive spectra of protons and pi minus mesons as a func- tion of their kinetic energies T in the lab. system for 4HeC and 12CC interacti- ons at the momentum 4.2 A GeV/c with different values of Q are used. The spect- ra are fitted by the exponential expressions and the Q-dependencies of the in- verses of slopes Ti are studied. It is found that these spectra have two compo- nents and contain the regime change points .In the TDN region the values of Ti for pi minus mesons begin to increase with increasing the number of protons. We consider this increasing to be a signal from the extreme states of nuclear mat- ter. The value of the "temperature" of these states is about 0.140 GeV.

hep-ex↗
arXiv1997

Single - particle correlations in events with the total disintegration of nuclei

New experimental data on the behaviour of the single-particle two-dimensional correlation functions R versus Q (Q is the number of nucleons emitted from nuc- lei) and Ap (Ap is the mass of projectile nuclei) are presented in this paper. The interactions of protons, d, 4He and 12C nuclei with carbon nuclei (at a momentum of 4.2 A GeV/c) are considered.The values of R are obtained separately for pi minus mesons and protons.In so doing,the values of R are normalized so that -1=<R=<1.The value of R=0 corresponds to the case of the absence of corre- lations.It has been found that the Q- and Ap-dependence of R takes place only for weak correlations (R< 0.3).In the main (90 %),these correlations are con- nected with the variable pt and have a nonlinear character, that is the regi- ons with different characters of the Q-dependence of R are separated: there is a change of regimes in the Q-dependences of R.The correlations weaken with increasing Ap, and the variable R gets the least values of all the considered ones in 12CC interactions.Simultaneously with weakening the correlations in the region of large Q, the character of the Q-dependence of R changes.

hep-ex↗