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A. V. Vinogradov

Publications and source records attributed to A. V. Vinogradov.

8 recordsLinked to original sources

On inverse problem with phase retrieval for an inclined line in the parabolic approximation

The inverse problem of amplitude reconstruction on an inclined line based on the values of amplitude or its module as recorded on semi-infinite line orthogonal to the beam propagation direction is considered within the framework of 2D parabolic equation. It is demonstrated that this inverse problem, in case when the complex image plane amplitude is known, can be reduced to a singular Cauchy type integral equation. The existence of its solutions requires that certain conditions be met but if a solution exists it is necessary unique. The obtained integral equation is then approximated piece-wisely and the resulting linear algebraic system is solved numerically while applying necessary regularization procedures to enhance the stability of its solutions. Finally, an iterative method of phase retrieval is developed and a set of numerical experiments is performed.

math.NA↗

On the number and spin of photons in classical electromagnetic field

A relativistically invariant expression for the number of photons in free classical electromagnetic field through the currents, that created the field, is derived based on the formula for the total energy--momentum of the field. It is demonstrated that it corresponds to the classical limit of the photon number operator known from the quantum electrodynamics. An expression for the total spin moment of the classical electromagnetic field is derived and it is shown that it can be interpreted in terms of spin moments of elementary photons. Similar to the total number of photons the classical spin moment is the limit of the quantum operator of the total spin. It is revealed that the total number of photons as well as the total spin moment are related to each other through a second order tensor, which can be expressed through currents that created the field.

physics.class-ph↗

Influence of the electron beam emittance on the polarization of a laser--electron X-ray generator

In this paper we analyze the polarization of the X-ray radiation coming from laser--electron X-ray generator (LEXG). We obtain general relations connecting the polarization state of outgoing X-ray radiation to the polarization state of laser beam as well as to the parameters of electron beam. We demonstrate that finite electron beam emittance causes a partial depolarization of initially fully polarized X-ray radiation even when the laser beam is fully polarized. We demonstrate with a number of numerical experiments that finite electron beam emittance can in some cases fundamentally alter the polarization state of X-ray radiation as compared to the polarization state of X-ray radiation scattered by electron beam with a zero emittance. Possible applications of polarized LEXG's radiation are discussed.

physics.acc-ph↗

Design study of compact Laser-Electron X-ray Generator for material and life science applications

X-Ray generations utilizing Thomson scattering fill in the gap that exists between conventional and synchrotron-based X-ray sources. They are expected to be more intense than X-ray tubes and more compact, accessible and less expensive than synchrotron. In this work, two operation modes of Thomson X-ray source are documented: quasi CW(QCW) and a pulsed one are considered for material sciences and medical applications being implemented currently at Synchrotron Radiation (SR) facilities.

physics.acc-ph↗

Cherenkov Glue in Opaque Nuclear Medium

The spectrum of Cherenkov gluons is calculated within the framework of in-medium QCD. It is compared with experimental data on the double-humped structure around the away-side jet obtained at RHIC. The values of the real and imaginary parts of the nuclear permittivity are obtained from these fits. It is shown that accounting for an additional smearing due to resonance-like production of final hadrons allows to achieve an agreement with experimental data.

hep-ph↗

Energy losses and efficiency of laser - electron X-ray generator for medical applications

A source of medical x-rays based on a 50 Mev storage ring and a quasi-continues picosecond laser is considered. It is shown that such generator produces useful X-ray flux with higher average power and higher efficiency than that of conventional X-ray tubes. The main energy losses are related to coherent synchrotron radiation. Taking this into account the required parameters of the storage ring and injector are determined.

physics.acc-ph↗