INVESTIGADORES
ROMERO marcelo Ariel
congresos y reuniones científicas
Título:
Charge Exchange in H+- Graphite Collisions: Leading role of Time-Energy Uncertainty.
Autor/es:
FERNANDO BONETTO; MARCELO ROMERO; ADALBERTO IGLESIAS-GARCÍA; RICARDO VIDAL; EDITH C. GOLDBERG
Lugar:
Foz do Iguaçu
Reunión:
Encuentro; Encuentro; XXXVIII Encontro Nacional de Fisica da Materia Condensada; 2015; 2015
Resumen:
Theformation of positive and negative ions in the scattering of protons by ahighly oriented pyrolytic graphite (HOPG) surface is theoretically andexperimentally analyzed for a large scattering angle in a backscatteringgeometric configuration. These ion fractions are contrasted with previousresults obtained using a forward scattering geometry. Low Energy Ion Scattering(LEIS) technique was used to measure the ion fractions involved.The choice ofthe projectile-target system was motivated by the fact that the interaction ofa hydrogen atom with a surface is the prototype system to study theintra-atomic Coulomb repulsion in an s-like valence orbital localized in theatom. We tried to answer the open questions related to the electroniccorrelation effects and the influence of the detailed surface band structure byusing appropriate theoretical models. The theoretical?experimental dataassessment allows us to infer how relevant are the different physicalingredients included in the model and the energy range where they play asignificant role. The most remarkable conclusion obtained from this comparisonis the non-validity of an adiabatic representation of the projectile energylevels (shifted by the interactions with the surface atoms), when the energyuncertainty introduced by the ion velocity becomes of the order of theelectronic repulsion.