INVESTIGADORES
VIDAL ricardo Alberto
artículos
Título:
Mechanisms of O2 sputtering from water ice by keV ions
Autor/es:
B. D. TEOLIS; R. A. VIDAL; J. SHI; R. A. BARAGIOLA
Revista:
PHYSICAL REVIEW B - CONDENSED MATTER AND MATERIALS PHYSICS
Editorial:
American Physical Society
Referencias:
Lugar: Ridge, NY; Año: 2005 vol. 72 p. 2454221 - 2454229
ISSN:
0163-1829
Resumen:
We have conducted experiments on the sputtering of water ice by 100 keV Ar+ between 20 and 150 K. Our findings indicate that the temperature dependence of the total sputtering yield is heavily influenced by the thermal and irradiation history of the ice, showing a complex dependence on irradiation fluence that is correlated to the ejection of O2 molecules. The results suggest that O2 produced by the ions inside the ice diffuses to the surface where it is trapped and then ejected via sputtering or thermal desorption. A high concentration of O2 can trap in a subsurface layer during bombardment at 130 K, which we relate to the formation of hydrogen and its escape from that region. A simple model allows us to determine the depth profile of the absolute concentration of O2 trapped in the ice.