Topological first-order solitons in a gauged CP(2)CP(2) model with the Maxwell-Chern-Simons action

We verify the existence of radially symmetric first-order solitons in a gauged $CP(2)$ scenario in which the dynamics of the Abelian gauge field is controlled by the Maxwell-Chern-Simons action. We implement the standard Bogomol'nyi-Prasad-Sommerfield (BPS) formalism, from which we obtain a well-defined lower bound for the corresponding energy (i.e. the Bogomol'nyi bound) and the first-order equations saturating it. We solve these first-order equations numerically by means of the finite-difference scheme, therefore obtaining regular solutions of the effective model, their energy being quantized according the winding number rotulating the final configurations, as expected. We depict the numerical solutions, whilst commenting on the main properties they engender.Comment: 8 pages, 9 figure

Long beating wavelength in the Schwarz-Hora effect

Thirty years ago, H.Schwarz has attempted to modulate an electron beam with optical frequency. When a 50-keV electron beam crossed a thin crystalline dielectric film illuminated with laser light, electrons produced the electron-diffraction pattern not only at a fluorescent target but also at a nonfluorescent target. In the latter case the pattern was of the same color as the laser light (the Schwarz-Hora effect). This effect was discussed extensively in the early 1970s. However, since 1972 no reports on the results of further attempts to repeat those experiments in other groups have appeared, while the failures of the initial such attempts have been explained by Schwarz. The analysis of the literature shows there are several unresolved up to now contradictions between the theory and the Schwarz experiments. In this work we consider the interpretation of the long-wavelength spatial beating of the Schwarz-Hora radiation. A more accurate expression for the spatial period has been obtained, taking into account the mode structure of the laser field within the dielectric film. It is shown that the discrepancy of more than 10% between the experimental and theoretical results for the spatial period cannot be reduced by using the existing quantum models that consider a collimated electron beam.Comment: 3 pages, RevTe

"Colliding beam" enhancement mechanism of deuteron-deuteron fusion reactions in matter

We suggest a ``ping-pong'' mechanism of enhancement for fusion reactions between a low energy external deuteron beam and the deuterons in a condensed matter or molecular target. The mechanism is based on the possibility of acceleration of a target deuteron by the Coulomb field of a projectile deuteron with its subsequent rebound from a heavy atom in matter and the following fusion of the two deuterons moving towards each other. This effectively converts the fixed target process into a colliding beam reaction. In a simple limiting case this reduces the negative penetrability exponent by a factor of $\sqrt{2}$. We also discuss a contribution given by ``zero oscillations'' of a bound target deuteron. The proposed mechanism is expected to be efficient in compounds with target deuterons localized in the vicinity of heavy atoms.Comment: 4 page

Suppression of stochastic pulsation in laser-plasma interaction by smoothing methods

Smoothing of laser-plasma interaction by ISI, RPP, SSD, etc. was mainly directed to overcome lateral nonuniformity of irradiation. While these problems are in no way less important, we derived numerically the model of the Laue rippling and hydrorelaxation model for explanation of the measured temporal pulsation in the 10- to 40-ps range and how the smoothing schemes suppress these pulsations. The partial standing wave fields of the normally coherent laser-irradiated plasma corona is then suppressed by smoothing and conclusion for tests for this model, e.g., by the "question mark experiment” is given. The result provides a physics solution of the laser interaction problem for direct-drive inertial fusion energ

Extreme laser pulses for possible development of boron fusion power reactors for clean and lasting energy

Extreme laser pulses driving non-equilibrium processes in high density plasmas permit an increase of the fusion of hydrogen with the boron isotope 11 by nine orders of magnitude of the energy gains above the classical values. This is the result of initiating the reaction by non-thermal ultrahigh acceleration of plasma blocks by the nonlinear (ponderomotive) force of the laser field, in addition to the avalanche reaction that has now been experimentally and theoretically manifested. The design of a very compact fusion power reactor is scheduled to produce then environmentally fully clean and inexhaustible generation of energy at profitably low costs. The reaction within a volume of cubic millimetres during a nanosecond can only be used for controlled power generation.Comment: 10 pages, 5 fugure

Modelling of Dynamic Strain Aging with a Dislocation-Based Isotropic Hardening Model and Investigation of Orthogonal Loading

Based on experimental results, a dislocation material model describing the dynamic strain aging\ud effect at different temperatures is presented. One and two stage loading tests were performed in\ud order to investigate the influence of the loading direction as well as the temperature influence due\ud to the hardening mechanism. Bergström’s theory of work hardening was used as a basis for the\ud model development regarding the thermal isotropic behavior as well as the Chaboche model to\ud describe the kinematic hardening. Both models were implemented in an in-house FE-Code in\ud order to simulate the real processes. The present paper discusses two hardening mechanisms,\ud where the first part deals with the pure isotropic hardening including dynamic strain aging and the\ud second part involves the influence of the loading direction regarding combined (isotropic and\ud kinematic) hardening behavior

Accounting for material scatter in sheet metal forming simulations

Robust design of forming processes is gaining attention throughout the industry. To analyze the robustness of a sheet metal forming process using Finite Element (FE) simulations, an accurate input in terms of parameter variation is required. This paper presents a pragmatic, accurate and economic approach for measuring and modeling one of the main inputs, i.e. material properties and its associated scattering. For the purpose of this research, samples of 41 coils of a forming steel DX54D+Z (EN 10327:2004) from multiple batches have been collected. Fully determining the stochastic material behavior to the required accuracy for precise modeling in FE simulations would involve performing many mechanical experiments. Instead, the present work combines mechanical testing and texture analysis to limit the required effort. Moreover, use is made of the correlations between the material parameters to efficiently model the material property scatter for use in the numerical robustness analysis. The proposed approach is validated by the forming of a series of cup products using the collected material. The observed experimental scatter can be reproduced efficiently using FE simulations, demonstrating the potential of the modeling approach and robustness analysis in general

Material Induced Anisotropic Damage

The anisotropy in damage can be driven by two different phenomena; anisotropic defor-mation state named Load Induced Anisotropic Damage (LIAD) and anisotropic (shape and/or distribution) second phase particles named Material Induced Anisotropic Damage (MIAD). Most anisotropic damage models are based on LIAD. This work puts emphasis on the presence of MIAD in DP600 steel. Scanning Electron Microscopic (SEM) analysis was carried out on undeformed and deformed tensile specimens. The martensite morphology showed anisotropy in size and orientation. Consequently, significant MIAD was observed in the deformed tensile specimens. A through thickness shear failure is observed in the tensile specimen, which is pulled along the rolling direction (RD), whereas a dominant ductile fracture is observed when pulled perpendicular to RD. The Modified Lemaitre’s (ML) anisotropic damage model is improved to account for MIAD in a phenomenological manner. The MIAD parameters are determined from tensile tests carried out in 0o, 45o and 90o to the RD. The formability of DP600 is lower in the RD compared to that in 90o to the RD, due to the phenomenon of MIAD