Channeling 2016

Session

S1.4: Channeling & Radiations in Crystals

27 Sept 2016, 16:50

Conveners

S1.4: Channeling & Radiations in Crystals

• Augusto Marcelli (LNF)

15. Coherent processes and channeling at high energy in thin crystals

Prof. Mykola Shul'ga (National Science Center "Kharkov Institute of Physics and Technology", 61108 Kharkov, Ukraine)

27/09/2016, 16:50

Oral presentation

At passing of charged high energy particles through crystal the phenomenon of channeling is possible, at which the particles move inside channels created by strings of crystal atoms or by crystal planes, by periodically deviating from the channel direction to small angles. In ultrathin crystals the phenomenon of channeling is absent, although there remains the possibility of manifestation of...

93. Observation of independence of the nuclear de-channeling length on the particle charge sign

Vincenzo Guidi (FE)

27/09/2016, 17:20

Oral presentation

Under coherent interactions, particles undergo correlated collisions with the crystal lattice and their motion result in confinement in the fields of atomic planes, i.e. particle channeling. Other than coherently interacting with the lattice, particles also suffer incoherent interactions with individual nuclei and may leave their bounded motion, i.e., they de-channel. This latter is the main...

152. OPTIMIZATION OF AN HYBRID POSITRON SOURCE USING CHANNELING

Dr Robert CHEHAB (LAL/IN2P3)

27/09/2016, 17:35

Oral presentation

The advantages of the hybrid positron source using channeling radiation, related to the yield, the converter heating and the Peak Energy Deposited Density (PEDD) in the converter , made it to be chosen as the baseline for CLIC. An optimization study concerning the positron converter –a granular target made of small tungsten spheres- has been worked out. The simulation results show that the...

115. Textured polycrystal for increasing of positrons production

Dr Alexander Shchagin (Kharkov Institute of Physics and Tecknology)

27/09/2016, 17:50

Oral presentation

Now, positrons are produced in tungsten single-crystalline and amorphous targets, see, e.g., [1]. To regret, application of tungsten single-crystals is restricted because of a short dechanneling length of incident electrons. We propose to apply textured polycrystalline target for increasing of the positron production. The polycrystalline target can be produced as a set rolled ...

97. Depth oscillations of electronuclear reactions caused by relativistic planar channelled electrons: quantum versus classical calculations

Mr Yuri Eykhorn (National Research Tomsk Polytechnic University)

27/09/2016, 18:05

Oral presentation

Depth oscillations of electronuclear reactions were observed in original experiment in [1]. The computer simulation of the depth oscillations effect of the electronuclear reactions yield was performed in [2] for 700 MeV electrons at <111> axial channelling in silicon crystal. In this work the oscillations effect is investigated for (220) planar channelled electrons in silicon crystal in...

19. The manifestation of the band structure in the photon emission spectrum of the fast above-barrier oriented particle

Dr Evgeny Mazur (NATIONAL RESEARCH NUCLEAR UNIVERSITY MEPHI)

27/09/2016, 18:20

Oral presentation

The calculation of the quasi-Bloch energy spectrum of the oriented fast charged particle entering the crystal at an angle substantially greater than the Lindhard angle is performed. It is shown that the band structure with the presence of allowed and forbidden bands completely preserved during the passage of fast charged particles high above the crystal potential. The processes of the photon...