Physics of Particles and Nuclei Letters最新文献

Within the gauge-theoretic approach of gravity, the gauging of an enlarged symmetry of the tangent space in four dimensions allows gravity to be unified with internal interactions. We study the unification of the conformal and noncommutative (fuzzy) gravities with internal interactions based on the (SO(10)) GUT.

We review some recent developments in 1st order GLSM construction, or so-called Gross–Neveu formalism for sigma models. We recall the general idea behind this framework and describe a 1st order GLSM data from which the general generalized Gross–Neveu model can be constructed, using (mathbb{C}{{mathbb{P}}^{{n - 1}}}) sigma model as simplest example. Then, we formulate a general statement that answers the question of which generalized Gross–Neveu models are equivalent to sigma models on compact homogeneous Hermitian spaces of classical groups endowed with the normal metrics.

In this article we obtained the four-loop β-function in N = 1 SQED with ({{N}_{{text{f}}}}) flavours regularized by higher derivatives using a special method of calculating vacuum supergraphs. To obtain contributions to the β-function from vacuum graphs we used a C++ computer program. Final result was compared with the anomalous dimension in previous order calculated earlier.

The α-shape factor of the real epithermal neutron spectrum, characterized by the 1/E^{1+ α} dependence, at the sample irradiation positions of the neutron production chamber installed at the IREN facility, was experimentally determined using the dual monitor method based on cadmium ratios. Two monitor sets, consisting of gold and copper foils, were employed for the determination of the α-shape factor. A revised equation for the determination of the α-shape factor was derived, which explicitly accounts for the effects of thermal and epithermal neutron self-shielding, as well as cadmium transmission of epithermal neutrons, in a logical and transparent manner. The arrangement of the correction factors for these effects in our proposed equation differs from that in the equations commonly used by other authors. The α-shape factor obtained using the proposed equation was compared with those calculated using several alternative equations employed by other research groups. The discrepancies observed among the values of the α-shape factor determined by solving different equations indicate that the placement of the correction factors within the equation significantly affects the result. Therefore, particular attention should be paid to this aspect when applying the dual monitor method for determining the α-shape factor.

We discus one-loop divergencies of the effective action in six-dimensional higher-derivative hypermultiplet model coupled with the external gauge background.

In this paper, we discuss the Yang–Baxter deformation as a method to explore gauge field theories through supergravity. Previous results in the development of this formalism for bivector deformations are provided, along with its advantages and challenges in the context of holography. We also present some results and conclusions from the development of the formalism for polyvector deformations in Type IIB backgrounds with block diagonal metrics and non-vanishing self-dual 5-form RR field strengths.

A methodology for assessing the efficiency and systematic error of the trigger system efficiency when selecting collision events (the main interaction trigger) is presented. It is found that an important factor leading to a decrease in the trigger efficiency is the passage of two or more beam ions within the trigger response time interval. A method for selecting events for analysis is proposed, which allows reducing the influence of this factor and saving event statistics. The parameters of various trigger elements are shown to vary during the entire session.

A model of the supersymmetric oscillator is considered which is based on a nonlinear differential-delay equation proposed by the author in 1992. This equation provides a realization of the Heisenberg–Weyl algebra by the mixed differential-difference operators and leads to a deformation of the Chebyshev–Hermite orthogonal polynomials. We discuss general solution of this equation in a series form and describe its particular explicit solution associated with the one-gap Lamé equation.

New one parameter family of exact solutions in general relativity with a scalar field has been found and analysed. It is assumed that space-time metric has the Liouville form, that is conformally flat, where conformal factor is the sum of four functions on single coordinates. The scalar field has exponential potential. Analysis of geodesics shows, that solutions are global. Depending on the value of the parameter, the respective metric describes, in particular, the evolution of the space-time with the naked singularity. The solution corresponding to the naked singularity provides smooth extension of the Friedmann universe with accelerated expansion through the zero of the scale factor back in time along geodesics.