On the deflection of a positron beam by the miscut surface of an oriented crystal

Abstract

Trajectories of relativistic positrons moving in the electric field of oriented crystal near its surface have been simulated. A positron beam enters the field of the crystal at a small angle to crystallographic planes. Thus, planar channeling conditions are satisfied. The miscut surface of a crystal has a specific shape of a step sequence of terraces. It has been shown that such a surface can deflect a noticeable fraction of the beam from the crystal surface by means of quasichanneling. The possibility of the experimental observation of this phe nomenon has been analyzed.

Deflection of positively charged heavy particles by the crystal miscut surface

“…This prevents observation of the features above described for ultra-relativistic nuclei with energies of about 100 GeV/nucleon. So, possible experiments to investigate these phenomena will require very specific preparation, and, as earlier shown for positrons [18], its observation should be easier for light relativistic particles.…”

“…The electric field of this structure is the deflecting field where one terrace stands out under another or is the channel field. Particle motion in the field of terrace-like structure was considered in [17] for protons and in [18] for positrons. In this work the simulations results for ultrarelativistic Pb nuclei are presented.…”

Advanced channeling technologies for X-ray applications

“…A new phenomenon on effective deflection of relativistic hadron and lepton beams by crystal miscut surface has been also predicted (Babaev et al, 2015a(Babaev et al, , 2015b. Due to extremely fine structure of the miscut surface the phenomenon might be applied for future accelerators dealing with nanoscale emittances.…”

Advanced Channeling Technologies in Plasma and Laser Fields

“…UA9 LNF team has proposed to use parametric X-ray radiation (PXR) for diagnostics of both beam-crystal orientation and crystal quality; first PXR measurements for SPS CERN protons in a bent crystal have been performed and successfully proved the predictions for PXR making evident the peak structure in the radiation both spectral and angular distributions [54][55][56]. A new phenomenon on effective deflection of relativistic hadron and lepton beams by crystal miscut surface has been predicted [57,58]. Due to extremely fine structure of the miscut surface the phenomenon might be applied for future accelerators dealing with nanoscale emittance.…”

“…Simultaneously with the technique application, theoretical background for the beam propagation in bent crystal planar channels has been developed. Within collaboration with Tomsk Polytechnic University a new computer code to simulate the processes of relativistic proton/ion beams propagation into various crystals have been proposed and developed in order to characterize the beam deflection inside bent crystals [50][51][52][53]. This activity takes place within international CERN project UA9 and aims in LHC beams collimation based on crystal channeling phenomenon.…”