[en] After a short discussion of the channeling concept and of the parameters used in its quantitative descriptions the paper presents the experimental method for channeling studies developed at the IPNE Cyclotron in Bucharest. For testing the experimental set-up the axial channeling of 5 MeV protons in 50 μm, respectively 100 μm, thick Si monocrystals has been measured. For the thin crystal and (111) axis the critical angle and the minimum yield took the values psisub(c) = 0.11deg and chisub(min) = 0.24 respectively, while for the (110) axis psisub(c) = 0.31deg and chisub(min) = 0.75. The channeling along (111) axis in the thick crystal is characterized by psisub(c) = 0.08deg and chisub(min) = O.67. Finally, the use of channeling for locating impurity atoms in the crystal lattice, for evaluating the radiation induced damages or for studying special crystals is shortly reviewed. (author)

No abstract available

[en] Channeling effect on a silicon single-crystal wafer cut along parallel to its (111) plane was investigated by using Rutherford back-scattering technique. Critical angles were measured for 325, 395 and 400 keV incoming proton energies. Experimentally measured parameters were compared to Lindhard's simple continuoum model calculations. (author)

[en] Short communication

[en] The values of photon beam divergence and angular beam acceptance of oriented ideal tungsten monocrystals are compared with a view of estimating the prospects of the suggested method of polarized photon beam production on TeV-accelerators during π⁰(η)-mesonic decay. The yield of decay photons does not exceed the value of 10^-4 ph/d. 7 refs

No abstract available

[en] The authors present early results from the CHANNEL code, which simulates the passage of ionized projectiles through bulk solids. CHANNEL solves the classical equations of motion for the projectile using the force obtained from the gradient of the quantum mechanically derived coulombic potential of the solid (determined via a full potential augmented plane wave FLAPW calculation on the bulk) and a quantum mechanical energy dissipation term, the stopping power, as determined from the local electron density, using the method of Echenique, Nieminen, and Ritchie. The code then generates the trajectory of the ionic projectile for a given initial velocity and a given incident position on the unit cell face. For each incident projectile velocity, the authors generate trajectories for incidence distributed over the channel face. The distribution of ranges generates an implantation profile. In this paper, they report ion (proton) implantation profiles for low energy protons with initial velocity along the (100) and (110) channel directions of diamond structured Silicon

[en] Plans and first results from Fermilab Experiment 853 are presented. E853 is an experiment to test the feasibility and efficiency of extracting a low-intensity beam from the halo of the Tevatron using channeling in a bent silicon crystal. The motivation of the experiment is to apply crystal extraction to trans-TeV accelerators like the SSC. Channeling developments related to crystal extraction and some early results from accelerator studies at the Tevatron are presented

No abstract available

[en] Briefly reviewed are the papers in which a new method of structural investigation of crystals-protonography has been develope in recent years. The method is based on the application of channeling and shadow effects. It is noted that the analysis of linear and point reflexes of the protonograms on the light testifies to the fact that they have fine structure. This peculiarity of the protonograms can give additional data on defects of the crystal lattice. A table of the basic characteristics of the structural analysis methods is presented