Conveners
S1.1 Channeling & Radiations in Crystals
- Sultan Dabagov (LNF)
Description
Chair Dabagov
Prof.
Nikolai Shul'ga
(Akhiezer Institute for Theoretical Physics of NSC KIPT, Karazin Kharkiv National University)
24/09/2018, 09:00
Oral presentation
At motion of fast charged particles in crystal at small angle to one of its axes or planes different coherent and interference effects are possible in interaction of particles with the lattice atoms. Thanks to these effects, the interaction cross-sections of particles with atoms may differ substantially from the corresponding cross-sections of particle interactions with the amorphous medium...
Prof.
Hartmut Backe
(Institute for Nuclear Physics)
24/09/2018, 09:30
Oral presentation
The formula of Baier et al. for the de-channeling length of electrons in single crystals
Lee = 2U_0 pvX_0/E_s^2 [1] was frequently used for a comparison with various calculations, including simulation calculations. It will be pointed out in this contribution, that the fundamental parameter E_s^2 = (2π/α) (m_ec^2)^2 = (15 MeV)^2 must be replaced by E_s = 10.6 MeV if thin crystals are used....
Dr
Alexei Sytov
(FE)
24/09/2018, 09:45
Oral presentation
In this work we present the CRYSTALRAD simulation code, including all the features of the CRYSTAL simulation code for calculation of charged particles trajectories in a bent crystal and RADCHARM++ routine for calculation of radiation. The CRYSTALRAD code is based on Monte Carlo simulations of trajectories in interplanar and interaxial electric field either in a straight or bent crystal with...
Mr
Sergii Trofymenko
(Akhiezer Institute for Theoretical Physics of NSC KIPT)
24/09/2018, 10:00
Oral presentation
The process of coherent X-ray emission by a high-energy electron successively crossing two parallel targets – thick upstream amorphous and ultra-thin downstream crystalline ones, separated by a certain distance – is considered. Inside the thick target the electron’s field becomes partially screened by the target polarization [1]. After crossing this target the electron still has suppressed...
Mr
Sergei Abdrashitov
(National Research Tomsk Polytechnic University)
24/09/2018, 10:15
Oral presentation
The radiation from relativistic electrons moving along a helical trajectory is known to possess the orbital angular momentum (OAM) [1]. An example of the trajectories of such a type is the trajectory of a charged particle in a helical undulator. Twisted photons with energy of 99 eV and OAM ± ħ are observed experimentally in the undulator radiation from 917 MeV electrons [2]. However, the...
Dr
Bruno Paroli
(Dipartimento di Fisica, Università degli Studi di Milano)
24/09/2018, 10:30
Oral presentation
Even though the generation of radiation carrying Orbital Angular Momentum (OAM) has been made both with visible light [1] and with millimeter-waves [2], the practical realization of high brilliance X-ray vortices is an open problem. The main limitation is related to the damage threshold of the optical elements.
Novel approaches to generate OAM X-ray by using relativistic beams interacting...
Andrea Mazzolari
(FE)
24/09/2018, 10:45
Oral presentation
In this work we report the observation of 855 MeV electrons deflection and radiation by ultrathin silicon and germanium crystals, bent along (111) planes, at the MAinzer Mikrotron MAMI. The crystal length of 15 μm of length was chosen to be comparable with the dechanneling length of electrons. In order to make the measurements for different values of bending radius of the same crystal we used...
