We investigate soliton collisions a one-parameter family of scalar field theories in 1+1D. The models have a sextic potential with three local minima, and for suitably small values of the parameter its kinks have an internal structure in the form of two weakly-bound subkinks. We show that for these values of the parameter kink collisions are best understood as an independent sequence of...
The total cross section of the process $e^+e^- \to \Lambda\bar{\Lambda}$ is calculated within the energy range close to the mass of $\psi(3770)$ charmonium state. Two different contributions were considered: the $D$-meson loop and the three gluon charmonium annihilation one. Both of them contribute noticeably and in sum fairly reproduce the data. Large relative phase for these contributions...
The Standard Model (SM) has been tested and confirmed by many experiments.
Nowadays, the focus has shifted beyond the SM by seeking
new particles and new interactions. No new particles were observed
directly at the Large Hadron Collider (LHC) at CERN.
However, there are indirect hints for new physics (NP).
Among them semileptonic B-meson decays via charged current
(branching...
In the report the elastic electron-trinucleon scattering in the relativistic impulse approximation is considered. The amplitudes for a trinucleon have been obtained by solving the relativistic generalization of the Faddeev equations with a multirank separable kernel of the nucleon-nucleon interactions. The static approximation and additional relativistic corrections for the...
We discuss the possibility that bubbles of a parity breaking hadronic medium may emerge in the central heavy ion collisions. After reviewing the methods to describe the mesons on a background with chiral imbalance such as effective field theories and holographic techniques, we discuss the influence of the boundaries on the vector meson propagation. We argue for the existence of the currents...
Our research is dedicated to studying the composite Higgs model in the framework of a soft-wall holography. The Higgs field arises as the pseudo-Goldstone mode corresponding to a dynamical symmetry breaking in a new strongly coupled sector leading to a first order phase transition. The bubble nucleation in the early universe can occur in this instance. We present the perturbation theory...
One-loop electroweak radiative corrections to dilepton production in hadron collisions via photon fusion for Large Hadron Collider (LHC) experimental program are estimated, the most attention is paid to hard bremstrahlung. Discussed reaction follows the Drell-Yan process, its studying is the actual task of LHC experimental program. Detailed numerical analysis of electroweak radiative effects...
The dominant radiative transitions of the charmonium low-lying excited states as well as strong decays of a heavy exotic charmonium-like state have been studied within a covariant quark model by involving the analytic confinement concept. We use the compositeness condition to eliminate any constituent degrees of freedom from the space of physical states and strictly fix the renormalization...
We shortly review progress in multilloop RG calculations achieved
after 2017 when the 5-loop QCD beta-function was first announced. We also
provide an update of developments related to the recently decoded
transcendental structure of MS-scheme beta-functions and anomalous dimensions.
The three-loop $\beta$-functions for the Minimal Supersymmetric Standard Model (MSSM) are obtained in case of using the higher covariant derivative regularization for an arbitrary supersymmetric subtraction scheme. Firstly, the anomalous dimensions defined in terms of the bare couplings are calculated for all MSSM chiral matter superfields. After that, using the NSVZ relations we construct the...
We study the possibility of the existence of the QCD CBK relation and its multiple-beta function representation in the gauge-invariant static potential motivated effective V-scheme at the four-loop level. This representation provides
interesting relations between definite terms of {\beta}-expanded coefficients
of Static potential, Adler D-function and Bjorken polarized sum rule.
The...
We demonstrate how to use our general result for the renormalization-group functions to compute the anomalous dimensions of various operators in a range of specific scalar models. Recent applications include the calculation of the scaling dimensions of different tensor operators in $O(n)$-symmetric and hypercubic theories.
We derive the full set of beta functions for the marginal essential
couplings of projectable Horava gravity in $(3+1)$-dimensional
spacetime. To this end we compute the divergent part of the one-loop
effective action in static background with arbitrary spatial
metric. The computation is done in several steps: reduction of the
problem to three dimensions, extraction of an operator square...
Helicity amplitudes in with massive fermions can be written in tensor form using 4-component spinors (bi-spinors). The approach is demonstrated using the examples of hard Bremsstrahlung processes for future $e^+e^-$ colliders.
We investigate properties of four-point colour ordered scattering amplitudes in
D=6 fishnet CFT. We show that these amplitudes are related via a very simple
relation to their four-dimensional counterparts. Exploiting this relation, we obtain a closed expression for these amplitudes and investigate its behaviour at weak and strong coupling in different kinematic regimes.
The Landau-Khalatnikov-Fradkin (LKF) transformation is a
powerful and elegant transformation allowing to study the gauge dependence of the propagator of charged particles interacting with gauge fields. With the help of this transformation, we derive a non-perturbative identity between massless propagators in two different gauges. In the case of quenched three-dimensional QED, from the LKF...
In this talk I'll discuss a holographic probes of a rotating $\mathcal{N}=4$ SYM quark-gluon plasma. Following the holographic duality a 4d rotating strongly-coupled QGP can be described by a rotating Kerr-AdS_5 black hole. The Kerr-AdS_5 black hole has a conformal boundary $R\times S^{3}$, on which the $N=4$ SYM theory (a thermal ensemble) "lives". Moreover, the Hawking temperature...
We propose a method for constructing equations of generalized 10D supergravity using non-unimodular bi-Killing Yang–Baxter deformations. The presented approach is generalized to the 11-dimensional case. Using non-unimodular three-
Killing generalized Yang–Baxter deformations, a generalization of the equations of 11D supergravity is obtained.
We consider the massless and massive theory of higher spin (HS) fields within the BRST approach and construct a (off-shell) general cubic interaction vertices corresponding to the irreducible HS fields on the d-dimensional flat spacetime. To this end, we develop a concept of deformation Noether's procedure of free gauge theory on a base of BRST approach with complete BRST operator.
As...
The talk is dedicated to some variants of Regge-Gribov model, namely, to simplified one-dimensional model with pomeron and odderon field
\begin{multline*}
H=-\left( \Phi^{+} \partial_y \Phi + \Psi^{+} \partial_y \Psi - L \right) = -\mu_P \Phi^{+}\Phi - \mu_O \Psi^{+} \Psi + \
i \lambda \left( \Phi^{+}\Phi^{+}\Phi + \Phi^{+}\Phi\Phi + 2 \Psi^{+} \Psi \Phi +2 \Phi^{+} \Psi^{+} \Psi -...
Within the framework of the model with quark-gluon strings (color flux tubes) as sources, the properties of the strongly intense variable Σ, which characterizes the correlations between the number of particles in two observation windows separated in rapidity, are studied. We use a Regge-like quasi-eikonal approach to find the distribution of strings in the transverse plane of pp-collision....
The properties of the multiplicity distribution of the charged particles, produced in pp collisions at high energy, can be studied using combinant analysis [1,2]. The modified combinants $C_j$ show the interplay between the neighboring probabilities, and satisfy the following recurrence relation:
$$
(N+1)P(N+1)=\sum\limits_{j=0}^{N}C_j P(N-j)
$$
The combinant analysis of the experimental...
We discuss a limits on
a hidden sector models, which have been excluded
recently by NA64 fixed-target experiment at CERN SPS.
Namely, new experimental bounds on Dark Photon,
millicharged fermions and axion-like particles are
obtained from the missing energy signatures of
the electron beam incident on a lead target of NA64.
We also discuss prospects of NA64 to exclude light
dark matter...
Following a nonperturbative formulation of strong-field QED developed in our earlier works, and using the Dirac model of the graphene, we construct a reduced QED_{3,2} to describe one species of the Dirac fermions in the graphene interacting with an external electric field and photons. On this base, we consider the photon emission in this model and construct closed formulas for the total...
A generalization of Quark Model to construction of hadron spectroscopy is suggested. The proposed approach is applied to the case of light nonstrange mesons. By assumption, all such mesons above 1 GeV appear due to creation of constituent quark-antiquark pairs «inside» the pi or rho(omega) mesons. These spin-singlet or triplet pairs dictate the quantum numbers of formed resonance. Basing on...
The analytical calculation of Feynman integrals is an important problem in modern quantum field theory. Of greatest interest are the so-called non-polylogarithmic Feynman integrals. For such integrals, there is no single universal technique that would allow to find an exact analytical solutions for all cases. This report will be devoted to this problem. In this work, we use an example of two...
In my talk, I will report on the recent four-loop calculation of the small cusp angle expansion of the cusp anomalous dimension in QCD and the heavy quark field anomalous dimension in HQET. Also, I will provide details on the calculation of four-loop integrals containing eikonal propagators with the method of difference equations in the space-time dimension.
In this work we study the early stages of p+p collisions in the framework of the color string model and their influence on observables sensitive to initial state such as forward–backward rapidity correlations. We explore an entire dynamics of strings by taking into account their movement in longitudinal direction due to momenta of strings endpoints [1], in transverse direction due to...
Good understanding of dense quark matter(tree-color QCD) is
crucial for lots of physical applications. For instance, it is important for different astrophysical and cosmological problems and modern heavy ion collision experiments. It is known that dense quark matter is strongly interacting system. For this reason it is difficult to obtain reliable results of its study within different...
Magnetic monopoles are essential ingredients for explaining the color confinement mechanism, and instantons induce chiral symmetry breaking. The magnetic monopoles and instantons are closely tied to one another in the QCD vacuum. Furthermore, the eta-prime meson is closely related to the topology of the QCD vacuum. However, it is difficult to demonstrate the relations among them by...
Originally synchrotron radiation problems were studied by classical methods. Later, quantum corrections were calculated, considering the emission of photons arising from electronic transitions between spectral levels. We consider an intermediate approach, in which electric currents generating the radiation are considered classical while the quantum nature of the radiation is taken into account...
We study theoretical possibility of resonant amplification of electromagnetic modes generated by a nonlinear effect in Euler-Heisenberg electrodynamics. Precisely, we examine the possibility of the amplification for the third harmonics induced by a single electromagnetic mode in radiofrequency cavity, as well as the generation of signal mode of combined frequencies induced by two pump modes...
Phase structure of dense quark matter with chiral and isospin imbalance is considered in the framework of effective models. There has been considered as two color as well as three color QCD. It was
shown that chiral imbalance has several rather peculiar properties such as being universal catalyzer,
i. e. it catalyzes all the considered symmetry breaking patterns in the system, including the...
