Coordinatori
S1.3 Channeling & Radiations in Crystals
- Hartmut Backe (Institute for Nuclear Physics)
Dr.
H.-Ulrich (Uli) Wienands
(Argonne National Laboratory)
25/09/18, 14:30
Oral presentation
In recent years, several key experiments channeling high-energy electrons and positrons have been performed in the US at SLAC. using the FACET and the ESTB beam facilities. The results include measurements of channeling parameters in a little-explored energy range and the first experimental demonstration at high energy of quasi-channeling oscillations predicted by Sytov et al. Quantitative...
Prof.
Victor Tikhomirov
(Research Institute for Nuclear Problems)
25/09/18, 15:00
Oral presentation
Classical trajectory simulations, widely used in crystals at high energies, have never been supported by a rigorous quantum treatment. To do this, both the notion of optic curved ray eiconal and Wigner function proved to be necessary. We reveal that, being essentially quantum in nature, incoherent scattering of relativistic elementary particles in crystal is correctly described by both the...
Dr.
Sergiy Shulga
(aNational Science Center “Kharkiv Institute of Physics and Technology)
25/09/18, 15:15
Oral presentation
At motion of a fast charged particle in crystal near the direction of one of main crystallographic planes, a periodical deviation of the trajectory from the initial direction is observed (channeling, over-barrier motion), that is accompanied by irradiation of the electromagnetic field quanta. If the target thickness is small compared to the radiation formation length, the spectral density of...
Prof.
Nikolay Kalashnikov
(National Research Nuclear University Mephi)
25/09/18, 15:30
Oral presentation
The ultra-relativistic electron with energy E up to 10^11 eV moving along the crystallographic axis in an axial channeling mode, can be considered as a non-relativistic 2D-atom, possessing the discrete spectrum of energies and orbital momentum, if the electron motion is considered in the so called accompanying reference system (ARS), moving parallel to the channeling axis with the velocity,...
Sig.
Aleksandr Savchenko
(NRNU MEPhI Moscow)
25/09/18, 15:45
Oral presentation
We continued our investigation of the non-dipolarity of channeling radiation (CR) at GeV beam energies [1] which remarkably change the CR spectrum and its intensity [2]. The experimental proof that CR and coherent bremsstrahlung (CB) substantially influence the output of positrons at conversion of γ-radiation into e+e- pairs in crystalline targets has been given at the KEK B facility [3]. An...
Dr.
Micola Bondarenco
(Kharkov Institute of Physics and Technology)
25/09/18, 16:00
Oral presentation
The analytic theory of volume reflection of fast charged particles in a bent crystal [1] is generalized to the case of an arbitrary interplanar potential shape. The mean deflection angle and the angular distributions for positively and negatively charged volume reflected particles are derived, with simplifications occurring under condition R>>R_c. Cases of crystal orientation (110) and (111)...
Dr.
Igor Kyryllin
(Akhiezer Institute for Theoretical Physics of National Science Center Kharkov Institute of Physics and Technology)
25/09/18, 16:15
Oral presentation
When a high-energy charged particle moves in a crystal having a small angle between its momentum and one of the main atomic axes or planes, correlations between successive collisions of the particle with neighboring atoms occur. These correlations give the possibility to deflect the direction of motion of the particle to the angles, which significantly exceed the critical angle of channeling....
