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Vladimir G. Baryshevsky

Publications and source records attributed to Vladimir G. Baryshevsky.

15 recordsLinked to original sources

Potential for measurement of the tensor electric and magnetic polarizabilities of the deuteron in storage-ring experiments with polarized beams

Measurement of the tensor electric and magnetic polarizabilities of the deuteron is of great interest, especially in connection with the possibilities of COSY and GSI. These polarizabilities can be measured in storage rings by the frozen spin method providing a disappearance of g-2 precession. This method will be used in the planned deuteron electric-dipole-moment experiment in storage rings. The tensor electric polarizability of the deuteron significantly influences the buildup of the vertical polarization in the above experiment. The spin interactions depending on the electric dipole moment, the tensor electric polarizability, and main systematical errors caused by field misalignments have very different symmetries. For the considered experimental conditions, the sensitivity to the deuteron EDM of $1\times10^{-29} e\cdot$cm corresponds to measuring the both of tensor polarizabilities with an accuracy of $δα_T\approxδβ_T\approx5\times10^{-42}$ cm$^3$. This conservative estimate can be improved by excluding the systematical error caused by the field instability which is negligible for the measurement of the tensor polarizabilities. To find the tensor magnetic polarizability, the horizontal components of the polarization vector should be measured.

nucl-ex↗

Spin rotation and oscillation of high energy particles in storage ring

Phenomena of rotation and oscillations of particle spin are discussed for particles rotating in storage ring. The fact that these effects are described by spin-dependent part of zero-angle scattering amplitude allows to use them for the measurement of this amplitude at different energies of colliding particles. It is shown that effect magnitudes are large and they can be observed at the existing accelerators.

hep-ph↗

Superradiance in volume diffraction grating

Volume Free Electron Laser (VFEL) was proposed in [1-4]. It can operate in the wide spectral range from microwaves to X-rays. To simulate the processes which take place in VFEL the superradiance from a short electron pulse moving in a volume diffraction grating is studied in wavelength range ~4 mm. It is supposed that Bragg condition for emitted photons is fulfilled and dynamical diffraction takes place. The spectral-angular distributions for transmitted and diffracted waves are derived. It is shown that the optimal geometry of diffraction exists and is determined by the energy and transverse size of electron beam.

physics.optics↗

Dependence of volume FEL (VFEL) threshold conditions on undulator parameters

The idea and principles of volume free electron lasers were proposed in [1-4]. It was shown there that volume distributed feedback (VDFB) can essentially reduce the threshold current of generation and provide the possibility of smooth frequency tuning. The present work considers an undulator VFEL with multiwave VDFB. It is shown that dependence of threshold current on the interaction length changes in the point of roots degeneration. This leads to the sharp decrease of start current if condition of dynamical diffraction is fulfilled. The dependence of amplification coefficient changes, too. So the interaction length for generation appears shorter. The proposed scheme can be used for generation in wide spectral range from microwaves to X-rays. The operating features of undulator VFEL is considered.

physics.optics↗

Influence of guiding magnetic field on emission of stimulated photons in generators utilizing periodic slow-wave structures

Effect of guiding magnetic field on evolution of stimulated emission is considered. It is shown that the transverse dynamics of electrons contributes to generation process and that contribution decreases with the magnetic field grows. The equation of generation for stimulated radiation of electron beam passing over periodic medium in magnetic field of arbitrary value is derived. The critical value of guiding field for which the transverse dynamics of electron don't contribute to emission is determined. It is shown, that transverse dynamics of electron modifies the boundary conditions. It follows from the derived generation equation that transverse dynamics yields to ~25% increase of the increment magnitude in high gain regime. In the limit of small signal the generation gain twice increases when transverse dynamics evolves. Obtained results are valid for every FEL system, which use the mechanism of waves slowing in the slow-wave structures for generation.

physics.class-ph↗

Time-reversal-violating optical gyrotropy

The T-reversal-violating optical gyrotropy is discussed. A new optical phenomenon of photon polarization plane rotation in a medium exposed to an electric field caused by the Stark mixing of atom (molecule) levels and T-odd phenomenon of photon polarization plane rotation appearing at photon passing through non-center-symmetrical diffraction grating are considered. The experimental methods to observe these phenomena are proposed.

hep-ph↗

Diffraction of X-ray pulse in crystals

The X-ray radiation delay law dependence on the diffraction asymmetry parameters is analyzed. It is shown that the use of subpicosecond pulses allows to observe the time delay of pulse in crystal phenomenon and to investigate the delay law experimentally. It is also shown that pulse delay law depends on the quanta polarization.

physics.optics↗

Parametric X-radiation for Bragg geomery

The PXR spectral-angular and angular distributions in Si and LiH crystals for Bragg geometry are presented. PXR for both the forward and backward diffraction is studied. It is shown that for Bragg geometry the contributions of both the slow and the fast waves in radiation intensity are comparable and only their joint account allows to describe the experimental results. The comparison of theory and experiment is carried out.

hep-ex↗

Phenomenon of the time-reversal-violating photon polarization plane rotation by a gas placed to an electric field

T-odd P-odd phenomenon of the photon polarization plane rotation (circular dichroism) is considered for an atomic (molecules) gas placed to an electric field. The expression for the T non-invariant polarizability of an atom (molecule) placed to an electric field is obtained. It is shown that the T-odd plane rotation angle increases when the interaction energy of an atom (molecule) with an electric field is the same order as the opposite parity levels spacing.

hep-ph↗

Volume free electron lasers

The equations describing the VFEL lasing in case of an electron beam moving either in a split of a diffraction grating or in a vacuum waveguide containing a diffraction grating (vacuum VFEL) have been obtained. The dispersion equation allowing to find the vacuum VFEL gain in one-mode generation regime have been considered. It is shown that the vacuum VFEL amplification and the generation process develop more intensively then in ordinary FEL using one-dimensional distributed feedback. Such the VFEL, if realised, could be made with much more compact device structure compared with the FEL and therefore, may be interesting for applications in different wavelength ranges: from submillimeter to X-ray. Such the VFEL can be realised on the basis of the existing accelerators.

physics.acc-ph↗