Monte Carlo Simulation Analysis of Proton‐Energy Spectra for Axial Channeling in Silicon in the Intermediate Energy Region

Abstract

A detailed theoretical analysis of experimental energy spectra of axial-channeled protons transmitted through thin silicon targets is performed by Monte Carlo calculations. Energy spectra are calculated for (1 lo), (1 1 l), and (1 12) channels in the energy region from 50 to 300 keV. The Monte Carlo program is based on the continuum string model. The energy loss on valence electrons is calculated on the basis of a modified Lindhard model for channeling energy loss and the stopping number is taken from the local density approximation of the Lindhard-Winther formalism. The anisotropic distribution of the valence electron density in a semiconductor is taken into account. Stopping due to core electrons is considered by a semiclassical approximation. Multiple scattering and energy straggling are included in the simulation program. The calculated energy spectra and channeling stopping powers are in good agreement with experimental ones. Mit

Axial channelling of low-energy antiprotons

“…In order to calculate the energy spectra of axially channelled antiprotons we use the Monte Carlo computer simulation of individual particle trajectories. A detailed description of the computer program AS^ as well as the basic physical assumptions used in the calculation were given in [14]. Here we briefly discuss the main characteristics of the model.…”

Feasibility study of high energy channeling experiments at the debrecen cyclotron

“…ordered materials (Si, ZnS, GaAs, etc.). The theory of interaction of energetic ions with the crystal-atoms has been developed [l-61. In the majority of laboratories dealing with the channeling phenomenon the Van de Graaff type accelerators are used for ion bombardment within the energy range of 0.5-3 MeV [7], but experiments and theoretical calculations have also been made at higher energies in different iontarget-crystal axis combinations [8-111, even in the GeV range. This technique has been used at higher energies fulfilling the requirements on the beam quality (parallel beam, angular spread,.…”

“…In such a way, selfsupporting samples made by relatively simple preparation can be used for performing penetration measurements (e.g., for measuring stopping power and range in channeling directions). The other possible goal of the method is to check the validity of different theories of ioncrystal(atom) interactions (e.g., interaction potentials) in an extended energy range [7].…”

Καναλισμός πρωτονίων ενέργειας 10-20 MeV σε νανοκρυσταλλικές δομές

“…Πάνω από πέντε δεκαετίες θεωρητικής και πειραματικής έρευνας του φαινομένου του καναλισμού σε κρυστάλλους έχουν προσφέρει πλήθος ενδιαφερόντων αποτελεσμάτων και εφαρμογών, όπως η εμφύτευση ιόντων σε κρυστάλλους, ο προσδιορισμός της πλεγματικής θέσης πρόσμιξης ή πλεγματικής ανωμαλίας σε κρυστάλλους, η μέτρηση του χρόνου ζωής βραχύβιων πυρήνων, η στροφή δέσμης φορτισμένων σωματιδίων, η ακτινοβολία καναλισμού κ.α. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31].…”

“…όπου u ⊥ το πλάτος της θερμικής ταλάντωσης στο εγκάρσιο επίπεδο[24]. Στην περίπτωσή μας μπορούμε να χρησιμοποιήσουμε την τιμή 8,5•10 -3 nm για το u ⊥ , που αντιστοιχεί στην τιμή για γραφίτη σε θερμοκρασία δωματίου.…”