Energy straggling of heavy ions in thin foils

The energy straggling of heavy ion beams at tandem energies, passing through thin foils, has been studied with ions of mass up to A = 35. Charge exchange in the foils has been found to have a considerable effect on the energy spread. Thickness non-uniformities in the foils can also make significant contributions. Extrapolation of the observations to the case of a uniform carbon stripper foil in a tandem accelerator suggests energy straggling of the order a few tenths per cent of the beam energy. However, large non-uniformities in the foil could appreciably worsen the beam resolution

Energy straggling of heavy ions in thin foils

The energy straggling of heavy ion beams at tandem energies, passing through thin foils, has been studied with ions of mass up to A = 35. Charge exchange in the foils has been found to have a considerable effect on the energy spread. Thickness non-uniformities in the foils can also make significant contributions. Extrapolation of the observations to the case of a uniform carbon stripper foil in a tandem accelerator suggests energy straggling of the order a few tenths per cent of the beam energy. However, large non-uniformities in the foil could appreciably worsen the beam resolution.La dispersion énergétique des faisceaux d'ions lourds, aux énergies tandem, qui traversent des feuilles minces, a été étudiée au moyen d'ions de masse allant jusqu'à A = 35. Les expériences ont permis de conclure que l'échange de charge des ions dans la feuille produit un grand effet sur la dispersion énergétique. Des inhomogénéités dans l'épaisseur de la feuille peuvent aussi provoquer des contributions significatives. L'extrapolation, à partir des observations, pour une feuille de stripping uniforme, dans un accélérateur tandem, suggère que l'énergie doit avoir une dispersion de l'ordre de quelques dixièmes d'un pour cent de l'énergie du faisceau. Cependant, des grandes inhomogénéités dans l'épaisseur de la feuille peuvent détériorer la résolution énergétique du faisceau

Selectivity improvement of gas sensors by radiolytic modification of the surface chemistry

International audienc

Radiolytic modification of gas sensor surface chemistry

International audienc