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Title: Electron emission and energy loss in grazing collisions of protons with insulator surfaces

Abstract

Electron emission from LiF, KCl, and KI crystal surfaces during grazing collisions of swift protons is studied using a first-order distorted-wave formalism. Owing to the localized character of the electronic structure of these surfaces, we propose a model that allows us to describe the process as a sequence of atomic transitions from different target ions. Experimental results are presented for electron emission from LiF and KI and energy loss from KI surfaces. Calculations show reasonable agreement with these experimental data. The role played by the charge of the incident particle is also investigated.

Authors:
;  [1];  [2];  [2];  [3];  [4];  [5];  [6]; ;  [7]
  1. Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas, and Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires (Argentina)
  2. Departamento de Fisica de Materiales, Facultad de Quimica, UPV/EHU, San Sebastian (Spain)
  3. (Spain)
  4. Centro Atomico Bariloche, San Carlos de Bariloche (Argentina)
  5. (DIPC), San Sebastian (Spain)
  6. Institut fuer Allgemeine Physik der TU Wien, Wiedner Haupstrasse 8-10, A-1040 Vienna (Austria)
  7. Institut fuer Physik, Humboldt Universitaet zu Berlin, Brook-Taylor-Strasse 6, D-12489 Berlin-Adlershof (Germany)
Publication Date:
OSTI Identifier:
21011245
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 76; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevA.76.012904; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; COLLISIONS; COMPUTER CALCULATIONS; CRYSTALS; DISTORTED WAVE THEORY; ELECTRON EMISSION; ELECTRONIC STRUCTURE; ELECTRONS; ENERGY LOSSES; ENERGY-LOSS SPECTROSCOPY; LITHIUM FLUORIDES; PARTICLES; POTASSIUM CHLORIDES; POTASSIUM IODIDES; PROTONS; SURFACES

Citation Formats

Gravielle, M. S., Miraglia, J. E., Aldazabal, I., Arnau, A., CentroMixto CSIC-UPV/EHU, San Sebastian, Ponce, V. H., Donostia International Physics Center, Aumayr, F., Lederer, S., and Winter, H. Electron emission and energy loss in grazing collisions of protons with insulator surfaces. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.76.012904.
Gravielle, M. S., Miraglia, J. E., Aldazabal, I., Arnau, A., CentroMixto CSIC-UPV/EHU, San Sebastian, Ponce, V. H., Donostia International Physics Center, Aumayr, F., Lederer, S., & Winter, H. Electron emission and energy loss in grazing collisions of protons with insulator surfaces. United States. doi:10.1103/PHYSREVA.76.012904.
Gravielle, M. S., Miraglia, J. E., Aldazabal, I., Arnau, A., CentroMixto CSIC-UPV/EHU, San Sebastian, Ponce, V. H., Donostia International Physics Center, Aumayr, F., Lederer, S., and Winter, H. Sun . "Electron emission and energy loss in grazing collisions of protons with insulator surfaces". United States. doi:10.1103/PHYSREVA.76.012904.
@article{osti_21011245,
title = {Electron emission and energy loss in grazing collisions of protons with insulator surfaces},
author = {Gravielle, M. S. and Miraglia, J. E. and Aldazabal, I. and Arnau, A. and CentroMixto CSIC-UPV/EHU, San Sebastian and Ponce, V. H. and Donostia International Physics Center and Aumayr, F. and Lederer, S. and Winter, H.},
abstractNote = {Electron emission from LiF, KCl, and KI crystal surfaces during grazing collisions of swift protons is studied using a first-order distorted-wave formalism. Owing to the localized character of the electronic structure of these surfaces, we propose a model that allows us to describe the process as a sequence of atomic transitions from different target ions. Experimental results are presented for electron emission from LiF and KI and energy loss from KI surfaces. Calculations show reasonable agreement with these experimental data. The role played by the charge of the incident particle is also investigated.},
doi = {10.1103/PHYSREVA.76.012904},
journal = {Physical Review. A},
number = 1,
volume = 76,
place = {United States},
year = {Sun Jul 15 00:00:00 EDT 2007},
month = {Sun Jul 15 00:00:00 EDT 2007}
}
  • Motivated by a recent experimental work [S. Lederer and H. Winter, Phys. Rev. A 73, 054901 (2006)] we study the contribution of the 3d shell electrons to the energy loss of 100 keV protons scattered off from the Cu(111) surface. To describe this process we use a multiple collision formalism, where the interaction of the projectile with 3d electrons is described by means of a sequence of single encounters with atoms belonging to the first atomic layer. In order to compare the theoretical energy loss with the experimental data, we add the contribution of valence electrons, which is evaluated inmore » linear response theory using a response function that incorporates information on the surface band structure. For completeness, the energy lost by protons is also calculated within a jellium model that includes 3d and valence electrons with equal footing. Fair agreement between theory and experiment exists when the 3d shell is taken into account in the calculation.« less
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  • In this work we evaluate the production of excitons of a lithium fluoride crystal induced by proton impact in the intermediate and high energy regime (from 100 keV to 1 MeV). A simple model is proposed to account for the influence of the Coulomb grid of the target by dressing crystal ions to transform them in what we call onions. The excited states of these onions can be interpreted as excitons. Within this model, total cross section and stopping power are calculated by using the first Born and the continuum distorted-wave (CDW) eikonal initial-state (EIS) approximations. We found that betweenmore » 7 and 30 excitons per incident proton are produced in grazing collisions with LiF surfaces, becoming a relevant mechanism of inelastic transitions.« less