2019 жыл
|
№ |
Мақаланың тақырыбы |
Авторлары |
Жыл |
Журналдың атауы |
Қысқаша аннотация |
| 1 |
No-scale supergravity with new Fayet-Iliopoulos term |
Aldabergenov, Y. |
2019 |
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 2019, 795, стр. 366–370, Q2 |
We find a new class of N=1 no-scale supergravity models with F- and D-term supersymmetry breaking, using a new Fayet-Iliopoulos term. The minimal setup contains one U(1) vector multiplet and one neutral chiral multiplet parametrizing SL(2,R)/U(1) manifold, with constant superpotential and linear gauge kinetic function. In our construction the FI term is field-dependent, and one can obtain flat vanishing potential (Minkowski vacuum) with broken SUSY, and global SL(2,R) invariance (self-duality) of the bosonic equations of motion. The spectrum of the model includes a massive spin-1/2 field as well as a vector, a scalar, and a pseudo-scalar – all classically massless. We discuss several modifications/extensions of the model as well as the introduction of matter fields. We also find a two-field extension of already existing no-scale model. |
| 2 |
Generalized dilaton–axion models of inflation, de Sitter vacua and spontaneous SUSY breaking in supergravity |
Aldabergenov, Y., Chatrabhuti, A., Ketov, S.V. |
2019 |
European Physical Journal C, 2019, 79(8), 713, Q2 |
We propose the unified models of cosmological inflation, spontaneous SUSY breaking, and the dark energy (de Sitter vacuum) in N= 1 supergravity with the dilaton–axion chiral superfield T in the presence of an N= 1 vector multiplet with the alternative Fayet–Iliopoulos term. By using the Kähler potential as K= - αlog (T+ T¯) and the superpotential as a sum of a constant and a linear term, we find that viable inflation is possible for 3 ≤ α≤ αmax where αmax≈ 7.235. Observations of the amplitude of primordial scalar perturbations fix the SUSY breaking scale in our models as high as 1013GeV. In the case of α> 3 the axion gets the tree-level (non-tachyonic) mass comparable to the inflaton mass. |
| 3 |
Polonyi-Starobinsky supergravity with inflaton in a massive vector multiplet with DBI and FI terms |
Abe, H., Aldabergenov, Y., Aoki, S., Ketov, S.V. |
2019 |
Classical and Quantum Gravity, https://doi.org/10.1088/1361-6382/ab0901
|
We propose the Starobinsky-type inflationary model in the matter-coupled N = 1 four-dimensional supergravity with the massive vector multiplet that has inflaton (scalaron) and goldstino amongst its field components, whose action includes the Dirac-Born-Infeld-type kinetic term and the generalized (new) Fayet-Iliopoulos-type term, without gauging the R-symmetry. The N = 1 chiral matter ('hidden sector') is described by the modified Polonyi model needed for spontaneous supersymmetry breaking after inflation. We compute the bosonic action and the scalar potential of the model, and show that it can accommodate the positive (observed) cosmological constant (as the dark energy) and the spontaneous supersymmetry breaking at high scale after the Starobinsky inflation. |
| 4 |
Modified born-infeld-dilaton-axion coupling in supersymmetry |
Aldabergenov, Y., Ketov, S.V. |
2019 |
Symmetry, 2019, 11(1), 14, Q2 https://doi.org/10.3390/sym11010014
|
We propose the supersymmetric extension of the modified Born-Infeld-axion-dilaton non-linear electrodynamics that has confined static abelian solutions used for describing the electromagnetic confinement in the presence of axion and dilaton fields, as well as charged matter. The supersymmetric extension also has the non-trivial scalar potential that implies the upper bounds on the matter fields. |
| 5 |
Leading-order relativistic corrections to the rovibrational spectrum of H2 + and HD+ molecular ions |
Aznabayev, D.T., Bekbaev, A.K., Korobov, V.I. |
2019 |
Physical Review A, 2019, 99(1), 012501, Q2 |
High-precision variational calculations of the operators for the relativistic corrections in the leading mα4 order are presented. The rovibrational states in the range of the total orbital angular momentum L=0-4 and vibrational quantum number v=0-10 for the H2+ and HD+ molecular ions are considered. We estimate that about 10 significant digits are obtained. This high precision is required for making theoretical predictions for transition frequencies at the level of 10-12 relative uncertainty. |
| 6 |
The Erez-Rosen solution versus the Hartle-Thorne solution |
Boshkayev, K., Quevedo, H., Nurbakyt, G., Malybayev, A., Urazalina, A. |
2019 |
Symmetry, 2019, 11(10), 1324, Q2 |
In this work, we investigate the correspondence between the Erez-Rosen and Hartle-Thorne solutions. We explicitly show how to establish the relationship and find the coordinate transformations between the two metrics. For this purpose the two metrics must have the same approximation and describe the gravitational field of static objects. Since both the Erez-Rosen and the Hartle-Thorne solutions are particular solutions of a more general solution, the Zipoy-Voorhees transformation is applied to the exact Erez-Rosen metric in order to obtain a generalized solution in terms of the Zipoy-Voorhees parameter δ = 1 + sq. The Geroch-Hansen multipole moments of the generalized Erez-Rosen metric are calculated to find the definition of the total mass and quadrupole moment in terms of the mass m, quadrupole q and Zipoy-Voorhees δ parameters. The coordinate transformations between the metrics are found in the approximation of ~q. It is shown that the Zipoy-Voorhees parameter is equal to δ = 1 - q with s = -1. This result is in agreement with previous results in the literature. |
| 7 |
Time evolution of rotating and magnetized white dwarf stars |
Becerra, L., Boshkayev, K., Rueda, J.A., Ruffini, R. |
2019 |
Monthly Notices of the Royal Astronomical Society, 2019, 487(1), стр. 812–818, Q1 |
We investigate the evolution of isolated, zero and finite temperature, massive, uniformly rotating and highly magnetized white dwarf stars under angular momentum loss driven by magnetic dipole braking. We consider the structure and thermal evolution of white dwarf isothermal cores taking also into account the nuclear burning and neutrino emission processes. We estimate the white dwarf lifetime before it reaches the condition either for a type Ia supernova explosion or for the gravitational collapse to a neutron star. We study white dwarfs with surface magnetic fields from 106 to 109 G and masses from 1.39 to 1.46 M⊙ and analyse the behaviour of the white dwarf parameters such as moment of inertia, angular momentum, central temperature, and magnetic field intensity as a function of lifetime. The magnetic field is involved only to slow down white dwarfs, without affecting their equation of state and structure. In addition, we compute the characteristic time of nuclear reactions and dynamical time scale. The astrophysical consequences of the results are discussed. |
| 8 |
A model for a dark matter core at the Galactic Centre |
Boshkayev, K., Malafarina, D. |
2019 |
Monthly Notices of the Royal Astronomical Society, 2019, 484(3), стр. 3325–3333, Q1 |
We consider a toy model for the supermassive compact object at the Galactic centre that does not require the presence of a black hole. We assume a matter distribution of weakly interacting particles with a density profile inferred from dark matter profiles in the outer regions. We show that rotation curves close to the centre of the Milky Way Galaxy can be explained within this model. We also show that the motion of test particles (stars) at distances of the order of 100 au cannot be distinguished from the motion of corresponding particles in the Schwarzschild geometry. However, differences arise at shorter distances, suggesting that it could be possible to observationally test the validity of the model in the near future. |
| 9 |
Extended logotropic fluids as unified dark energy models |
Boshkayev, K., D’Agostino, R., Luongo, O. |
2019 |
European Physical Journal C, 2019, 79(4), 332, Q2 |
We study extended classes of logotropic fluids as unified dark energy models. Under the hypothesis of the Anton–Schmidt scenario, we consider a universe obeying a single fluid model with a logarithmic equation of state. We investigate the thermodynamic and dynamical consequences of an extended version of the Anton–Schmidt cosmic fluids. Specifically, we expand the Anton–Schmidt pressure in the infrared regime. The low-energy case becomes relevant for the universe as regards acceleration without any cosmological constant. We therefore derive the effective representation of our fluid in terms of a Lagrangian depending on the kinetic term only. We analyze both the relativistic and the non-relativistic limits. In the non-relativistic limit we construct both the Hamiltonian and the Lagrangian in terms of density ρ and scalar field ϑ, whereas in the relativistic case no analytical expression for the Lagrangian can be found. Thus, we obtain the potential as a function of ρ, under the hypothesis of an irrotational perfect fluid. We demonstrate that the model represents a natural generalization of logotropic dark energy models. Finally, we analyze an extended class of generalized Chaplygin gas models with one extra parameter β. Interestingly, we find that the Lagrangians of this scenario and the pure logotropic one coincide in the non-relativistic regime. |
| 10 |
Measurement and analysis of 10B + 12C elastic scattering at energy of 41.3 MeV |
Burtebayev, N., Nassurlla, M., Sabidolda, A., Kemper, K.W., Ibraheem, A.A., Janseitov, D, et al. |
2019 |
International Journal of Modern Physics E |
Angular distribution of the 10B +12C elastic scattering was measured at Elab(10B) = 41.3MeV. Experimental data showed a significant increase in differential cross-sections at backward angles. The optical model with phenomenological potentials reproduces well the experimental cross-sections in the region of the angles of the forward hemisphere, but is not able to explain the increase in cross-sections at large angles. The distorted wave Born approximation method was used to reproduce the experimental data at large angles (> 90°) by taking into consideration a deuteron transfer. Spectroscopic amplitude has been extracted for the configuration 12C → 10B + d from the analysis. |
| 11 |
Mechanism of the 11 B(α ,t) 12 C reaction at an energy of 40 MeV, role of exchange processes and collective excitations |
Burtebayev, N., Sakuta, S.B., Nassurlla, M., Wolińska-Cichocka, M., Khojayev, R. |
2019 |
European Physical Journal A, 2019, 55(3), 38, Q2 |
The differential cross sections of triton from the 11 B(α,t) reaction with transitions to the ground (0 + ) and excited states of the 12 C nucleus at E x = 4. 44 MeV (2 + ), 7.65 MeV (0 + ), 9.64 MeV (3 - ) and 14.08 MeV (4 + ) have been measured at an α-particles energy of 40 MeV. Analysis of the measured angular distributions was carried out in the framework of the coupled reaction channels method considering the contribution of the 8 Be cluster exchange mechanism. It is shown that the direct mechanism with proton transfer dominates at an energy of 40 MeV, and the heavy particle transfer is noticeable only at large angles. An exception is the transition to the 14.08 MeV (4 + ) state, which is possible only by the transfer of the 8 Be cluster. It is established that the couplings between the excited states of 12 C, arising from the nonsphericity of the nucleus, have little effect on the (α, t) reaction cross sections in the forward hemisphere, but strongly affect the cross sections at large angles. |
| 12 |
New results for neutron radiative capture on 10Be at energies between 25.3 meV and 10.0 MeV |
Dubovichenko, S.B., Burkova, N.A., Afanasyeva, N.V., Dzhazairov-Kakhramanov, A.V., Tkachenko, A.S. |
2019 |
Astroparticle Physics, 2019, 104, стр. 91–101, Q2 |
Using the framework of the modified potential cluster model, we succeed in correctly describing the available experimental data for neutron radiative capture on 10Be total cross sections at low, astrophysical and thermal energies. Unlike our earlier work, the present calculations are based on new experimental data for Coulomb dissociation provided by Prof. T. Aumann and Prof. T. Nakamura. The energy range was extended from 10−5 to 104 keV for the theoretical cross sections, covering a range of temperatures between 0.01 and 10 T9. The role of the halo asymptotics of the extra-core neutron in 11Be was also taken into account. The parametrization of the reaction rates for the processes 10Be(n,γ0+1)11Be are obtained in an analytical form that is convenient for future calculations of different scenarios involving element synthesis in r-processes, as widely discussed in the context of boron and beryllium chains in our previous work. |
| 13 |
Energy conditions for a T2 wormhole at the center |
Dzhunushaliev, V., Folomeev, V., Kleihaus, B., Kunz, J. |
2019 |
Physical Review D, 2019, 100(8), 084008, Q1 |
Within general relativity, we determine the conditions needed for the existence of a toroidal T2 wormhole. For this purpose, we employ the requirements of the positiveness of the second derivatives of the relevant components of the metric, which describe an increase in the linear sizes (or the area) of the cross section of the throat. The corresponding inequalities for the central energy density and pressures of the matter and for the metric are obtained. |
| 14 |
Rotating wormhole solutions with a complex phantom scalar field |
Chew, X.Y., Kleihaus, B., Kunz, J., Dzhunushaliev, V., Folomeev, V. |
2019 |
Physical Review D, 2019, 100(4), 044019, Q1 |
We consider rotating wormhole solutions supported by a complex phantom scalar field with a quartic self-interaction, where the phantom field induces the rotation of the spacetime. The solutions are regular and asymptotically flat. A subset of solutions describing static but not spherically symmetric wormholes is also obtained. |
| 15 |
Dirac star in the presence of Maxwell and Proca fields |
Dzhunushaliev, V., Folomeev, V. |
2019 |
Physical Review D, 2019, 99(10), 104066, Q1 |
We consider configurations consisting of a gravitating nonlinear spinor field ψ, with a nonlinearity of the type λ(ψ̄ψ)2, minimally coupled to Maxwell and Proca fields through the coupling constants QM [U(1) electric charge] and QP, respectively. In order to ensure spherical symmetry of the configurations, we use two spin-1/2 fields having opposite spins. By means of numerical computations, we find families of equilibrium configurations with a positive Arnowitt-Deser-Misner (ADM) mass described by regular zero-node asymptotically flat solutions for static Maxwell and Proca fields and for stationary spinor fields. For the case of the Maxwell field, it is shown that, with increasing charge QM, the masses of the objects increase and diverge as the charge tends to a critical value. For negative values of the coupling constant λ, we demonstrate that, by choosing physically reasonable values of this constant, it is possible to obtain configurations with masses comparable to the Chandrasekhar mass and with effective radii of the order of kilometers. It enables us to speak of an astrophysical interpretation of such systems, regarding them as charged Dirac stars. In turn, for the system with the Proca field, it is shown that the mass of the configurations also grows with increasing both |λ| and the coupling constant QP. Although in this case the numerical calculations do not allow us to make a definite conclusion about the possibility of obtaining masses comparable to the Chandrasekhar mass for physically reasonable values of λ, one may expect that such masses can be obtained for certain values of free parameters of the system under consideration. |
| 16 |
Dirac stars supported by nonlinear spinor fields |
Dzhunushaliev, V., Folomeev, V. |
2019 |
Physical Review D, 2019, 99(8), 084030, Q1 |
We study configurations consisting of a gravitating spinor field ψ with a nonlinearity of the type λ(ψ̄ψ)2. To ensure spherical symmetry of the configurations, we use two spin-12 fields forming a spin singlet. For such systems, we find regular stationary asymptotically flat solutions describing compact objects. For negative values of the coupling constant λ, it is shown that, by choosing physically reasonable values of this constant, it is possible to obtain configurations with masses comparable to the Chandrasekhar mass. It enables us to speak of an astrophysical interpretation of the obtained systems, regarding them as Dirac stars. |
| 17 |
Non-Abelian Proca-Dirac-Higgs theory: Particlelike solutions and their energy spectrum |
Dzhunushaliev, V., Folomeev, V., Makhmudov, A. |
2019 |
Physical Review D, 2019, 99(7), 076009, Q1 |
We study a system consisting of a non-Abelian SU(2) Proca field interacting with nonlinear scalar (Higgs) and spinor fields. For such a system, it is shown that particlelike solutions with finite energy do exist. It is demonstrated that the solutions depend on three free parameters of the system, including the central value of the scalar field ξ0. For some fixed values of ξ0, we find energy spectra of the solutions. It is shown that for each of the cases under consideration, there is a minimum value of the energy Δ=Δ(ξ0) [the mass gap Δ(ξ0) for a fixed value of ξ0]. The behavior of the function Δ(ξ0) is studied for some range of ξ0. |
| 18 |
Thin-shell toroidal wormhole |
Dzhunushaliev, V., Folomeev, V., Kleihaus, B., Kunz, J. |
2019 |
Physical Review D, 2019, 99(4), 044031, Q1 |
We consider a topologically nontrivial thin-shell wormhole with a throat in the form of a T2 torus. It is shown that (i) such a wormhole is stable with respect to excitations of the throat; (ii) not all energy conditions are violated for such wormholes; (iii) if any of the energy conditions is violated, this violation occurs only partially in some region on the throat, and in other regions the violation is absent. Also, we discuss the differences between spherical S2 wormholes and toroidal T2 wormholes under investigation. |
| 19 |
The motion of color-charged particles as a means of testing the non-Abelian dark matter model |
Dzhunushaliev, V., Folomeev, V., Protsenko, N. |
2019 |
International Journal of Modern Physics D, 2019, 28(1), Q2 |
A possibility is discussed to experimentally test a dark matter model supported by a classic non-Abelian SU(3) Yang-Mills gauge field. Our approach is based on the analysis of the motion of color-charged particles in the background of color electric and magnetic fields using the Wong equations. Estimating the magnitudes of the color fields near the edge of a galaxy, we employ them in obtaining the general analytic solutions to the Wong equations. Using the latter, we calculate the magnitude of the extra acceleration of color-charged particles related to the possible presence of the color fields in the neighborhood of Earth. |
| 20 |
Clusterization and strong coupled-channels effects in deuteron interaction with 9Be nuclei |
Urazbekov, B.A., Denikin, A.S., Lukyanov, S.M., Kuterbekov, K.A., Zholdybayev, T., et al. |
2019 |
Journal of Physics G: Nuclear and Particle Physics, 2019, 46(10), 105110, Q2 |
Angular distributions of protons, deuterons, tritons and alpha particles emitted in the d + 9Be reaction at E lab = 19.5 and 35.0 MeV have been measured. The elastic scattering channel is analysed in the framework of both the optical model and the coupled-channel approach. The interaction potential of the d + 9Be system is calculated in the framework of the Double-Folding model using the α + α + n three-body wave function of the 9Be nucleus. The (d, p) and (d, t) one-nucleon-transfer reactions are analysed within the coupled-reaction-channel approach. The spectroscopic amplitudes for the different nuclear cluster configurations are calculated. Differential cross sections for the reaction channel 9Be()7Li are calculated including all possible reaction mechanisms within the coupled-reaction-channel method. Corresponding contributions to the cross sections are analysed. |
| 21 |
Hydrogen isotopic effect during the graphite high-temperature corrosion in water vapours |
Chikhray, Y., Askerbekov, S., Kenzhina, I., Nesterov, E., Varlamova, N., et al. |
2019 |
International Journal of Hydrogen Energy, 2019, 44(55), стр. 29365–29370, Q2 |
This paper presents the results on a study the processes of physicochemical interactions of water with graphite. The main regularities of the formation of H2, HD and D2 molecules on the graphite surface were determined. It was shown that the fraction of D2 and HD in the gaseous outcome increases in the process of heating, and the quasi-equilibrium state of the graphite's absorption of hydrogen isotopes at the initial stages of interaction is significant: the flow of dissolved atoms into the sample volume is higher than the desorption flow. We suppose that this is due to the higher rate of dissolution of hydrogen atoms in the volume of graphite. We also estimated also the separation factor for the graphite surface-volume system for hydrogen atoms, which was 1.53 for the selected experimental conditions. The temperature dependence of the effective rate constant Ks for the formation of hydrogen isotope molecules in the interaction of graphite with water vapour in the range of 1100 °C–1200 °C was determined. It turned out that KS(D2) > KS(HD) > KS(H2). |