615 articles – 3068 Notices  [english version]
HAL : hal-00021951, version 1

Fiche détaillée  Récupérer au format
Physical Review A: Atomic, Molecular and Optical Physics 70 (2004) 032902
Electron emission induced by fast heavy ions in a thin silicon crystal
F. Barrué1, M. Chevallier1, D. Dauvergne1, R. Kirsch1, J.-C. Poizat1, C. Ray1, L. Adoui2, A. Cassimi2, H. Rothard2, M. Toulemonde2, C. Cohen3, A. L'Hoir3, Dominique Vernhet3, C. Demonchy4, L. Giot4, W. Mittig4, S. Pita4, P. Roussel-Chomaz4, A. Billebaud5

We report observations of backward and forward electron emission by a thin silicon crystal target traversed by 29 MeV/u Pb56+ incident ions. For each incident ion we have performed measurements of backward and forward electron emission, of the energy loss and of the charge state of the transmitted ion. The crystal target was traversed by incident ions either in random incidence or in axial alignment conditions. In both cases these correlated measurements bring original information on electron emission. In random conditions, using an incident ion species with a charge quite far from equilibrium, we observe correlations between backward and forward electron emission, that we understand when analyzing the associated charge exchange and energy-loss data. In channeling conditions, we added electron emission measurements to simultaneous energy-loss and charge state measurements (that are known to characterize quite precisely the type of trajectory of a projectile transmitted through a thin crystal). This allowed us to observe the reduced electron emission due to hyperchanneled ions, that interact mainly with target valence electrons, and also the enhanced electron emission due to projectiles entering the crystal very close to atomic strings.
1 :  IPNL - Institut de Physique Nucléaire de Lyon
2 :  CIRIL (ENSICAEN) - Centre Interdisciplinaire de Recherche Ions Lasers
3 :  GPS - Groupe de Physique des Solides
4 :  GANIL - Grand Accélérateur National d'Ions Lourds
5 :  LPSC - Laboratoire de Physique Subatomique et de Cosmologie
Physique/Physique/Physique Atomique
Electron emission – channeling