arXiv subjects

Igor Volobuev

Publications and source records attributed to Igor Volobuev.

8 recordsLinked to original sources

arXiv2024

On Compton ionization of a hydrogen atom by twisted photons

The differential probability of the process of Compton ionization of a hydrogen atom by a cylindrical electromagnetic wave is calculated taking into account the finite size of the target, which resulted in the appearance of a dependence of this value on the angular momentum of the cylindrical wave. It is shown that the use of a cylindrical wave instead of a plane wave does not lead to new angular distributions of the reaction products.

physics.atom-ph↗

arXiv2024

Quantization of electromagnetic field in the Schwarzschild spacetime

We discuss the problem of canonical quantization of electromagnetic field in the Schwarzschild spacetime. It is shown that a consistent procedure of canonical quantization of the field can be carried out without taking into account the internal region of the black hole. We prove that there exists a unitary gauge, which can be viewed as a combination of the Coulomb and Poincare gauges and is compatible with the field equations. The solutions corresponding to the stationary one-particle states of the electromagnetic field are studied, the canonical commutation relations and the Hamiltonian of the quantized electromagnetic field are obtained.

gr-qc↗

arXiv2023

Quantization of spinor field in the Schwarzschild spacetime and spin sums for solutions of the Dirac equation

We discuss the problem of canonical quantization of a free massive spinor field in the Schwarzschild spacetime. It is shown that a consistent procedure of canonical quantization of the field can be carried out without taking into account the internal region of the black hole, the canonical commutation relations in the resulting theory hold exactly and the Hamiltonian has the standard form. Spin sums are obtained for solutions of the Dirac equation in the Schwarzschild spacetime.

gr-qc↗

arXiv2023

Notes on the inverse Compton scattering

The paper deals with kinematic conditions for the inverse Compton scattering of photons by relativistic electrons and the polarizations of the colliding particles, which affect the value of the differential cross section of the process. A significant influence of the electron and photon helicity on the value of the cross section has been found. In the ultrarelativistic case, a surprising effect of an almost twofold increase in the cross section of scattering in the direction of the initial electron momentum has also been discovered, when the initial photon momentum is transverse to that of the initial electron.

hep-ph↗

arXiv2023

Doubling of physical states in the quantum scalar field theory for a remote observer in the Schwarzschild spacetime

We discuss the problem of canonical quantization of a free real massive scalar field in the Schwarzschild spacetime. It is shown that a consistent procedure of canonical quantization of the field can be carried out without taking into account the black hole interior, so that in the resulting theory the canonical commutation relations are satisfied exactly, and the Hamiltonian has the standard form. However, unlike some papers, in which the expansion of the quantum field in spherical harmonics is used, here we use an expansion in scatteringlike states for energies larger than the mass of the field. This reveals a strange property of the resulting quantum field theory - doubling of the quantum states, which look as having the same asymptotic momentum to an observer located far away from the black hole. This purely topological effect cannot be eliminated by moving away from the black hole.

gr-qc↗

arXiv2022

Quantum field-theoretical description of neutrino oscillations in magnetic field

It is shown that the processes of neutrino oscillations in a magnetic field can be consistently described in the framework of a new quantum field-theoretical approach without use of the neutrino flavor states. It is based on the Feynman diagram technique with a modified distance-dependent propagator, which takes into account the geometry of neutrino oscillation experiments. Processes of neutrino oscillations in a magnetic field, where the neutrinos are detected through the weak charged- and neutral-current interaction, have been studied and numerical calculations have been carried out for some specific examples. Implications for the solar neutrinos are briefly discussed, and formulas for the asymptotic values of the normalized probability of solar neutrino oscillation processes are derived, which coincide with the observable ratio of the measurable neutrino flux to that predicted by the standard solar model.

hep-ph↗

arXiv2020

The specificity of the interactions of electroweak gauge bosons coming from extra dimensions

We discuss the specificity of the interactions of the electroweak gauge boson excitations in models with warped extra dimensions. In particular, we show that the couplings of the gauge boson excitations $W^{\prime}$, $Z^{\prime}$, and $γ^\prime$ to the SM gauge bosons treated as the zero modes of the 5D gauge fields are either exactly equal to zero or very much suppressed. In the former case, the three-particle and four-particle interaction Lagrangians of the SM gauge bosons and their lowest excitations are found explicitly. Meanwhile, the couplings of $W^{\prime}$, $Z^{\prime}$, and $γ^\prime$ to the SM fermions are non-zero allowing for their production and decays. These are the characteristic features of the gauge boson excitations in models with warped extra dimensions, which distinguish them from the gauge boson excitations in other models beyond the SM.

hep-ph↗

arXiv2018

Simple Standard Model Extension by Heavy Charged Scalar

We consider a Standard Model extension by a heavy charged scalar gauged only under the $U_{Y}(1)$ weak hypercharge gauge group. Such an extension, being gauge invariant with respect to the SM gauge group, is a simple special case of the well known Zee model. Since the interactions of the charged scalar with the Standard Model fermions turn out to be significantly suppressed compared to the Standard Model interactions, the charged scalar provides an example of a long-lived charged particle being interesting to search for at the LHC. We present the pair and single production cross sections of the charged scalar at different colliders and the possible decay widths for various boson masses. It is shown that the current ATLAS and CMS searches at 8 and 13 TeV collision energy lead to the bounds on the scalar boson mass of about 300--320 GeV. The limits are expected to be much larger for higher collision energies and, assuming $15~ab^{-1}$ integrated luminosity, reach about 2.7 TeV at future 27 TeV LHC thus covering the most interesting mass region.

hep-ph↗