Abstract: A Monte Carlo study of identified particle ratio fluctuations at LHC energies is carried out in the framework of HIJING model using the fluctuation variable . The simulated events for Pb-Pb collisions at and 5.02 TeV and Xe-Xe collisions at are analyzed. From this study, it is observed that the values of ,, and follow the similar trends of energy dependence as observed in the most central collision data by NA49, STAR, and ALICE experiments. It is also observed that for all the three combinations of particles for semicentral and central collisions, the model predicted values of for Pb-Pb collisions at agree fairly well with those observed in the ALICE experiment. For peripheral collisions, however, the model predicted values of are somewhat smaller, whereas for and it predicts larger values as compared to the corresponding experimental values. The possible reasons for the observed differences are discussed. The values scaled with charged particle density when plotted against exhibit a flat behaviour, as expected from the independent particle emission sources. For and combinations, a departure from the flat trend is, however, observed in central collisions in the case of low window when the effect of jet quenching or resonances is considered. Furthermore, the study of dependence on particle density for various collision systems (including proton-proton collisions) suggests that at LHC energies values for a given particle pair are simply a function of charged particle density, irrespective of system size, beam energy, and collision centrality. PubDate: Tue, 12 Oct 2021 08:20:01 +000
Abstract: LYSO scintillation crystals, due to their significant characteristics such as high light yield, fast decay time, small Moliére radius, and good radiation hardness, are proposed to be used for the electromagnetic calorimeter section of the Turkish Accelerator Center Particle Factory (TAC-PF) detector. In this work, the center of gravity technique was used to determine the impact coordinates of an electron initiating an electromagnetic shower in a LYSO array, in a calorimeter module containing nine crystals, each in cross-section and 200 mm in length. The response of the calorimeter module has been studied with electrons having energies in the range 0.1 GeV-2 GeV. By using the Monte Carlo simulation based on Geant4, the two-dimensional position resolution of the module is obtained as at the center of the crystal. PubDate: Wed, 15 Sep 2021 02:20:00 +000
Abstract: The quark-quark (QQ) interaction as a perturbed term to the nucleon-nucleon interaction (NN) without any coupling between them is studied in a hybrid model. This model is used to calculate the ground-state energies of 2H1 and 4He2 nuclei. In a semirelativistic framework, this model is encouraged for light nuclei and the instanton-induced interaction by using the QQ potential and the NN interaction for a small scale around the hadron boundaries. This hybrid model depends on two theories, the one-boson exchange potential (OBEP) and the Cornell-dressed potential (CDP) for QQ. A small effect of quark-quark interaction is obtained on the values of the ground-state energies, around 6.7 and 1.2 percentage for 2H1 and 4He2, respectively nuclei. PubDate: Mon, 06 Sep 2021 02:05:01 +000
Abstract: String geometry theory is a candidate of the nonperturbative formulation of string theory. In order to determine the string vacuum, we need to clarify how superstring backgrounds are described in string geometry theory. In this paper, we show that all the type IIA, IIB, SO(32) type I, and SO(32) and heterotic superstring backgrounds are embedded in configurations of the fields of a single string geometry model. In particular, we show that the configurations satisfy the equations of motion of the string geometry model in if and only if the embedded string backgrounds satisfy the equations of motion of the supergravities, respectively. This means that classical dynamics of the string backgrounds are described as a part of classical dynamics in string geometry theory. Furthermore, we define an energy of the configurations in the string geometry model because they do not depend on the string geometry time. A string background can be determined by minimizing the energy. PubDate: Tue, 17 Aug 2021 11:05:03 +000
Abstract: The glueballs lead to gluon and QCD monopole condensations as by-products of color confinement. A color dielectric function coupled with a Abelian gauge field is properly defined to mediate the glueball interactions at confining regime after spontaneous symmetry breaking (SSB) of the gauge symmetry. The particles are expected to form through the quark-gluon plasma (QGP) hadronization phase where the free quarks and gluons start clamping together to form hadrons. The QCD-like vacuum , confining potential , string tension , penetration depth , superconducting and normal monopole densities (), and the effective masses ( and ) will be investigated at finite temperature . We also calculate the strong “running” coupling and subsequently the QCD -function. The dual superconducting nature of the QCD vacuum will be investigated based on monopole condensation. PubDate: Tue, 10 Aug 2021 15:43:42 +000
Abstract: The Schrödinger equation is solved numerically for charmonium using the discrete variable representation (DVR) method. The Hamiltonian matrix is constructed and diagonalized to obtain the eigenvalues and eigenfunctions. Using these eigenvalues and eigenfunctions, spectra and various decay widths are calculated. The obtained results are in good agreement with other numerical methods and with experiments. PubDate: Fri, 30 Jul 2021 02:35:01 +000
Abstract: We exploit the theoretical strength of the supervariable and Becchi-Rouet-Stora-Tyutin (BRST) formalisms to derive the proper (i.e., off-shell nilpotent and absolutely anticommuting) (anti-)BRST symmetry transformations for the reparameterization invariant model of a nonrelativistic (NR) free particle whose space and time variables are a function of an evolution parameter . The infinitesimal reparameterization (i.e., 1D diffeomorphism) symmetry transformation of our theory is defined w.r.t. this evolution parameter . We apply the modified Bonora-Tonin (BT) supervariable approach (MBTSA) as well as the (anti)chiral supervariable approach (ACSA) to BRST formalism to discuss various aspects of our present system. For this purpose, our 1D ordinary theory (parameterized by ) is generalized onto a -dimensional supermanifold which is characterized by the superspace coordinates where a pair of the Grassmannian variables satisfy the fermionic relationships: ,, and is the bosonic evolution parameter. In the context of ACSA, we take into account only the -dimensional (anti)chiral super submanifolds of the general-dimensional supermanifold. The derivation of the universal Curci-Ferrari- (CF-) type restriction, from various underlying theoretical methods, is a novel observation in our present endeavor. Furthermore, we note that the form of the gauge-fixing and Faddeev-Popov ghost terms for our NR and non-SUSY system is exactly the same as that of the reparameterization invariant SUSY (i.e., spinning) and non-SUSY (i.e., scalar) relativistic particles. This is a novel observation, too. PubDate: Fri, 23 Jul 2021 07:20:01 +000
Abstract: The aim of the research is to examine the dependence of plasma pinch properties and radiation emissions on the atomic number of the operating gas within the dense plasma focus device (NX2) when using hydrogen and argon gases. Simulation was performed with Lee’s code on an NX2 dense plasma focus at a constant gas pressure value (). The results showed that the minimum radius of the plasma focus in the case of the hydrogen plasma pinch was 0.30 cm and in the case of the argon plasma pinch 0.17 cm, and this affected the value of the radiation emission as it was and 11 J for the hydrogen and argon pinch, respectively. The energy of the ion beam released by the breakdown of the plasma pinch was found as in the state of hydrogen and in the state of argon. PubDate: Mon, 12 Jul 2021 07:35:01 +000
Abstract: The differential cross-section in squared momentum transfer of ,,,,,,,,, and produced in high-energy virtual photon-proton (), photon-proton (), and proton-proton () collisions measured by the H1, ZEUS, and WA102 Collaborations is analyzed by the Monte Carlo calculations. In the calculations, the Erlang distribution, Tsallis distribution, and Hagedorn function are separately used to describe the transverse momentum spectra of the emitted particles. Our results show that the initial- and final-state temperatures increase from lower squared photon virtuality to a higher one and decrease with the increase of center-of-mass energy. PubDate: Thu, 17 Jun 2021 10:50:00 +000
Abstract: This article is devoted to exploring the Rényi holographic dark energy model in the theory of Chern-Simons modified gravity. We studied the deceleration parameter, equation of state, and cosmological plane considering the Amended FRW modal. Modified field equations of -gravity theory gave two independent solutions. In the first case, this model provided the transitional change from deceleration to acceleration compatible with collected observational data. However, it supported a decelerating phase of expansion only in the second case. It was noted that the Equation of State advocated the dominance era under the influence of dark energy in the first case and the second predicted the influence of CDM. In both cases, voted that the universe is in a freezing region and its cosmic expansion is more rapidly accelerated in the background of Chern-Simons modified gravity. PubDate: Wed, 16 Jun 2021 09:20:00 +000
Abstract: In this paper, a trial function method is employed to find exact solutions to the nonlinear Schrödinger equations with high-order time-dependent coefficients. This system might be used to describe the propagation of ultrashort optical pulses in nonlinear optical fibers, with self-steepening and self-frequency shift effects. The new general solutions are found for the general case including the Jacobi elliptic function solutions, solitary wave solutions, and rational function solutions which are presented in comparison with the previous ones obtained by Triki and Wazwaz, who only studied the special case . PubDate: Wed, 16 Jun 2021 08:50:00 +000
Abstract: We study the and decay channels of the next-to-lightest CP-even Higgs boson of the NMSSM at the LHC, where the is produced in gluon fusion. It is found that while the discovery is impossible through the latter channel, the former one in the final state is a promising channel to discover the with masses up to around 250 GeV at the LHC. Such a discovery of the is mostly accompanied with a light , which is a clear evidence for distinguishing the NMSSM from the MSSM since such a light is impossible in the MSSM. PubDate: Mon, 14 Jun 2021 07:50:01 +000
Abstract: We analyze the transverse momentum () spectra of lepton pairs () generated in the Drell-Yan process, as detected in proton-nucleus (pion-nucleus) and proton-(anti)proton collisions by ten collaborations over a center-of-mass energy or if in a simplified form) range from GeV to above 10 TeV. Three types of probability density functions (the convolution of two Lévy-Tsallis functions, the two-component Erlang distribution, and the convolution of two Hagedorn functions) are utilized to fit and analyze the spectra. The fit results are approximately in agreement with the collected experimental data. Consecutively, we obtained the variation law of related parameters as a function of and invariant mass . In the fit procedure, a given Lévy-Tsallis (or Hagedorn) function can be regarded as the probability density function of transverse momenta contributed by a single quark () or anti-quark (). The Drell-Yan process is then described by the statistical method. PubDate: Tue, 01 Jun 2021 11:20:01 +000
Abstract: We propose a new model for hadrons with quantum mechanical attractive and repulsive interactions sensitive to some spatial correlation length parameter inspired by the Beth-Uhlenbeck quantum mechanical nonideal gas model (Uhlenbeck and Beth, 1937). We confront the thermodynamics calculated using our model with a corresponding recent lattice data at four different values of the baryon chemical potential, over temperatures ranging from to and for five values for the correlation length ranging from to 0.2 fm. For equilibrium temperatures up to the vicinity of the chiral phase transition temperature ≃160 MeV, a decent fitting between the model and the lattice data is observed for different values of , especially at , where is in MeV and is in fm. For the vanishing chemical potential, the uncorrelated model , which corresponds to the ideal hadron resonance gas model, seems to offer the best fit. The quantum hadron correlations seem to be more probable at nonvanishing chemical potentials, especially within the range . PubDate: Thu, 27 May 2021 06:20:01 +000
Abstract: We study a phenomenological model that mimics the characteristics of QCD theory at finite temperature. The model involves fermions coupled with a modified Abelian gauge field in a tachyon matter. It reproduces some important QCD features such as confinement, deconfinement, chiral symmetry, and quark-gluon-plasma (QGP) phase transitions. The study may shed light on both light and heavy quark potentials and their string tensions. Flux tube and Cornell potentials are developed depending on the regime under consideration. Other confining properties such as scalar glueball mass, gluon mass, glueball-meson mixing states, and gluon and chiral condensates are exploited as well. The study is focused on two possible regimes, the ultraviolet (UV) and the infrared (IR) regimes. PubDate: Wed, 05 May 2021 06:05:01 +000
Abstract: In this paper, we study the finite temperature-dependent Schrödinger equation by using the Nikiforov-Uvarov method. We consider the sum of the Cornell, inverse quadratic, and harmonic-type potentials as the potential part of the radial Schrödinger equation. Analytical expressions for the energy eigenvalues and the radial wave function are presented. Application of the results for the heavy quarkonia and meson masses are in good agreement with the current experimental data except for zero angular momentum quantum numbers. Numerical results for the temperature dependence indicates a different behaviour for different quantum numbers. Temperature-dependent results are in agreement with some QCD sum rule results from the ground states. PubDate: Wed, 05 May 2021 04:50:00 +000
Abstract: We have estimated centrality variation of chemical freeze-out parameters from yield data at midrapidity of , and , for collision energies of RHIC (Relativistic Heavy Ion Collider), Beam Energy Scan (RHIC-BES) program, and LHC (Large Hadron Collider). We have considered a simple hadron resonance gas model and employed a formalism involving conserved charges () of QCD for parameterization. Along with temperature and three chemical potentials (), a strangeness undersaturation factor () has been used to incorporate the partial equilibration in the strange sector. Our obtained freeze-out temperature does not vary much with centrality, whereas chemical potentials and seem to have a significant dependence. The strange hadrons are found to deviate from a complete chemical equilibrium at freeze-out at the peripheral collisions. This deviation appears to be more prominent as the collision energy decreases at lower RHIC-BES energies. We have also shown that this departure from equilibrium reduces towards central collisions, and strange particle equilibration may happen after a threshold number of participants in - collision. PubDate: Wed, 28 Apr 2021 05:50:01 +000
Abstract: We consider the phenomenon of spontaneous pair production in the presence of an external electric field for noncommutative Yang-Mills theories. Using Maldacena’s holographic conjecture, the threshold electric field for pair production is computed from the quark/antiquark potential for noncommutative theories. As an effect of noncommutativity, the threshold electric field is seen to be smaller than its commutative counterpart. We also estimate the correction to the production rate of quark/antiquark pairs to the first order of the noncommutative deformation parameter. Our result bears resemblance with an earlier related work (based on field-theoretic methods). PubDate: Sat, 24 Apr 2021 04:50:00 +000
Abstract: We study the transverse momentum and pseudorapidity spectrum of the top quark and their decay products, the system, and the total number of jets in proton-proton (pp) collisions at 13 TeV by using the Tsallis-Pareto-type function and the three-source Landau hydrodynamic model, respectively. The related parameters, such as the effective temperature of the interacting system (), the nonextensivity of the process (), and the width () of pseudorapidity distribution, are extracted. PubDate: Fri, 23 Apr 2021 09:05:00 +000
Abstract: In this study, pentaquark composed of a baryon , and a meson is considered. Pentaquark is as a bound state of two-body systems composed of a baryon and a meson. The calculated potential will be expanded and replaced in the Schrödinger equation until tenth sentences of expansion. Solving the Schrödinger equation with the expanded potential of Pentaquark leads to an analytically complete approach. As a consequence, the binding energy of pentaquark and wave function is obtained. The results will be presented in the form of tables so that we can review the existence of pentaquark . Then, the wave function will be shown on diagrams. Finally, the calculated results are compared with the other obtained results, and the mass of observing pentaquark and the radius of pentaquark are estimated. PubDate: Wed, 21 Apr 2021 08:35:01 +000
Abstract: We investigate the recently proposed holographic dark energy models with the apparent horizon as the IR cutoff by assuming Kaniadakis and generalized Tsallis entropies in the fractal universe. The implications of these models are discussed for both the interacting () and noninteracting () cases through different cosmological parameters. Accelerated expansion of the universe is justified for both models through deceleration parameter . In this way, the equation of state parameter describes the phantom and quintessence phases of the universe. However, the coincidence parameter shows the dark energy- and dark matter-dominated eras for different values of parameters. It is also mentioned here that the squared speed of sound gives the stability of the model except for the interacting case of the generalized Tsallis holographic dark energy model. It is mentioned here that the current dark energy models at the apparent horizon give consistent results with recent observations. PubDate: Tue, 20 Apr 2021 06:05:01 +000
Abstract: This paper proposes a new base material, a mixture of alcohol and water, for liquid scintillators. A possibility of using alcohol as a new detection solution in a particle detector is described. A liquid scintillator is widely used in various fields because of its high light yield. In addition, it is very important to develop a stable liquid scintillator for particle detectors or other medical applications. To date, there have been no previous R&D studies elsewhere for the use of alcohol in particle detectors, and no market products are available of this type. Thus, there is a room for improvement. This paper describes the brief synthesizing process of the alcohol-based liquid scintillator by varying the mixing ratio of each component that makes up the liquid scintillator. The several feasible physical and optical properties of an alcohol-based liquid scintillator were investigated and presented. Finally, as one of its applications, a range (beam-path length) measurement using an electron beam in medical physics is introduced after irradiating an alcohol-based liquid scintillator with electron beam energies of 6~12 MeV. The measurement results were compared with a Monte Carlo simulation, Novalis Tx, a phantom, and a CT image. In the near future, the new alcohol-based liquid scintillator could be used for particle detector or medical imaging applications. PubDate: Fri, 16 Apr 2021 08:50:02 +000
Abstract: We study the effects of T-odd interactions of top-quark via the pair production of the top-quark in the semileptonic detection modes at the Large Hadron Collider by means of the T-odd observables constructed through the momenta of the observed decay products of the top (and anti-top)-quark for a wide range of CP-violating scale . Estimates on sensitivities of the coupling strength of such interactions for 13 TeV LHC energy with , and for HL-LHC with 14 TeV energy with integrated luminosities of ,,, and are also presented for ranging between and 2 TeV. PubDate: Thu, 15 Apr 2021 11:05:01 +000
Abstract: By employing a pseudoorthonormal coordinate-free approach, the Dirac equation for particles in the Kerr–Newman spacetime is separated into its radial and angular parts. In the massless case to which a special attention is given, the general Heun-type equations turn into their confluent form. We show how one recovers some results previously obtained in literature, by other means. PubDate: Wed, 14 Apr 2021 11:20:01 +000
Abstract: We use a semiclassical version of the Nexus paradigm of quantum gravity in which the quantum vacuum at large scales is dominated by the second quantized electromagnetic field to demonstrate that a virtual photon field can affect the geometric evolution of Einstein manifolds or Ricci solitons. This phenomenon offers a cogent explanation of the origins of astrophysical jets, the cosmological constant, and a means of detecting galactic dark matter. PubDate: Mon, 12 Apr 2021 10:05:01 +000
Abstract: In this work, we present an exact analysis of the two-dimensional noncommutative hydrogen atom. In this study, the Levi-Civita transformation was used to perform the solution of the noncommutative Schrodinger equation for Coulomb potential. As an important result, we determine the energy levels for the considered system. Using the result obtained and experimental data, a bound on the noncommutativity parameter was obtained. PubDate: Thu, 08 Apr 2021 09:05:02 +000
Abstract: Transverse momentum spectra of proton, deuteron, and triton in gold-gold (Au-Au) collisions at 54.4 GeV are analyzed in different centrality bins by the blast wave model with Tsallis statistics. The model results are approximately in agreement with the experimental data measured by STAR Collaboration in special transverse momentum ranges. We extracted the kinetic freeze-out temperature, transverse flow velocity, and freeze-out volume from the transverse momentum spectra of the particles. It is observed that the kinetic freeze-out temperature is increasing from the central to peripheral collisions. However, the transverse flow velocity and freeze-out volume decrease from the central to peripheral collisions. The present work reveals the mass dependent kinetic freeze-out scenario and volume differential freeze-out scenario in collisions at STAR Collaboration. In addition, parameter characterizes the degree of nonequilibrium of the produced system, and it increases from the central to peripheral collisions and increases with mass . PubDate: Thu, 01 Apr 2021 06:35:00 +000
Abstract: We address the effect of an anomalous triple gauge boson couplings on a physical observable for the electroweak sector of the Standard Model, when the symmetry is spontaneously broken by the Higgs mechanism to . Our calculation is done within the framework of the gauge-invariant, but path-dependent variable formalism is an alternative to the Wilson loop approach. Our result shows that the interaction energy is the sum of a Yukawa and a linear potential, leading to the confinement of static probe charges. The point we wish to emphasize, however, is that the anomalous triple gauge boson couplings () contributes to the confinement for distances on the intranuclear scale. PubDate: Sun, 28 Mar 2021 07:20:00 +000
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