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1
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On the analytic properties of the S-matrix for the unknown interactions surrounded by centrifugal and rapidly decreasing potentials

100%
Olkhovsky V.
Open Physics
|
2011
|
vol. 9
|
issue 1
13-44
EN
The analytic structure of the non-relativistic unitary and non-unitary S-matrix is investigated for the cases of the unknown interactions with the unknown motion equations inside a sphere of radius a, surrounded by the centrifugal and rapidly decreasing (exponentially or by the Yukawian law or by the more rapidly decreasing) potentials. The one-channel case and special examples of many-channel cases are considered. Some kinds of symmetry conditions are imposed. The Schroedinger equation for r > a for the particle motion and the condition of the completeness of the correspondent wave functions are assumed. The connection of the obtained results with the usual (temporal) causality is examined. Finally a scientific program is presented as a clear continuation and extension of the obtained results.
2
Content available remote

On the modification of methods of nuclear chronometry in astrophysics and geophysics

63%
Olkhovsky V., Dolinska M.
Open Physics
|
2010
|
vol. 8
|
issue 1
95-100
EN
In practically all known methods of nuclear chronometry until now, research has usually taken into account the life-times of only the fundamental states of α-radioactive nuclei. But in the processes of nuclear synthesis in stars and under the influence of constant cosmic radiation on the surfaces of planets the excitations of the α-radioactive nuclei are still ongoing. Between these processes there are states with excited α-particles inside the parent nuclei leading to much smaller life-times. And inside the large masses of stellar, terrestrial and meteoric substances there are transitions between different internal conditions of radioactive nuclei that are accompanied by infinite chains of γ-radiations with subsequent γ-absorptions, further γ-radiations, etc. For a description of the α-decay evolution that accounts for such excited states and multiple γ-radiations and γ-absorptions inside stars, and under the influence of cosmic radiation on the Earth’s surface we present a quantum-mechanical approach, which is based on the generalized Krylov-Fock theorem. A few simple estimations are also presented. These approaches lead to the conclusion that the usual (non-corrected) “nuclear clocks” do really point not to realistic values but to the upper limits of the durations of α-decay in stellar and planet processes.
3
Content available remote

Tunnelling time of a gaussian wave packet through two potential barriers

63%
Petrillo V., Olkhovsky V.
Open Physics
|
2005
|
vol. 3
|
issue 3
339-350
EN
The resonant and non-resonant dynamies of a Gaussian quantum wave packet travelling through a double barrier system is studied as a function of the initial characteristics of the spectrum and of the parameters of the potential. The behaviour of the tunnelling time shows that there are situations where the Hartman effect occurs, while, when the resonances are dominant, and in particular for b>π/Δk (b being the inter-barrier distance and Δk the spectrum width), the tunnelling time becomes very large and the Hartman effect does not take place.
4
Content available remote

On new experimental data manifesting the time resonances (or explosions)

51%
Olkhovsky V., Dolinska M., Omelchenko S.
Open Physics
|
2011
|
vol. 9
|
issue 4
1131-1133
EN
Some new applications of the time resonances (explosions) to new experimental data on high-energy nuclear processes are presented. These new experimental data are fitted rather well by the approach of the time resonances for the compound nuclei and clots.
5
Content available remote

The possibility of time resonance (explosion) phenomena in high-energy nuclear reactions

51%
Olkhovsky V., Dolinska M., Omelchenko S.
Open Physics
|
2006
|
vol. 4
|
issue 2
223-240
EN
This study shows that the exponential decrease of the energy spectra, accompanied by slight oscillations, with final-fragment energy in high-energy nuclear reaction, and independent of fragments, targets, projectiles, and projectile energies, can be explained under some conditions in the range of strongly overlapping compound resonances by a new phenomenon of time resonances (explosions). These time resonances (explosions) correspond to the formation of a few highly-excited, non-exponentially decaying nuclear clots (partial compound nuclei consisting of certain small groups of target and projectile nucleons). The proposed approach is an alternative way of analyzing experimental data compared with the majority of known descriptions (for instance, fireball models). This is a new and more general version of the time-evolution approach compared with the Izumo-Araseki time compound-nucleus model.
6
Content available remote

Particle tunneling and scattering in a three-dimensional potential with a barrier

51%
Olkhovsky V., Petrillo V., Jakiel J., Kantor W.
Open Physics
|
2008
|
vol. 6
|
issue 1
122-127
EN
The particle tunneling through a 3-D rectangular potential barrier has been studied. The simplest model for multiple internal reflections has been assumed. The explicit expression for all the transmission and reflection probability amplitudes have been derived, as well as the tunneling and reflection phase times.
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