The parameters of proton beams accelerated by a high-intensity short pulse laser from a thin foil are studied for various small plasma gradients created on the rear-surface of the foil. Compared to the case of an initially cold foil, the proton beam maximum energy as well as the beam spectral slope reduce steadily when increasing the gradient scale length. The measurements are in good agreement with simulations. For future ion-driven Fast Ignition of fusion targets, multi-kJ PetaWatt laser pulses will induce target preheat due to the leading part of the laser pulse. Estimates of such preheat in these conditions suggest that it should modify by less than 10 % the ion beam parameters compared to the case of a unheated target.
Laser-acceleration of high-energy protons in small-scale gradients / Fuchs, J; CECCHETTI C., A; Borghesi, M; Grismayer, T; Antici, Patrizio; Atzeni, Stefano; Audebert, P; D'Humieres, E; Mora, P; Pipahl, A; Romagnani, L; Schiavi, Angelo; Sentoku, Y; Toncian, T; Willi, O.. - In: JOURNAL OF PHYSICS. CONFERENCE SERIES. - ISSN 1742-6596. - STAMPA. - 112:(2008), p. 022082. (Intervento presentato al convegno 5th International Conference on Inertial Fusion Sciences and Applications tenutosi a Kobe, Japan nel SEP 09-14, 2007) [10.1088/1742-6596/112/022082].
Laser-acceleration of high-energy protons in small-scale gradients
ANTICI, PATRIZIO;ATZENI, Stefano;SCHIAVI, ANGELO;
2008
Abstract
The parameters of proton beams accelerated by a high-intensity short pulse laser from a thin foil are studied for various small plasma gradients created on the rear-surface of the foil. Compared to the case of an initially cold foil, the proton beam maximum energy as well as the beam spectral slope reduce steadily when increasing the gradient scale length. The measurements are in good agreement with simulations. For future ion-driven Fast Ignition of fusion targets, multi-kJ PetaWatt laser pulses will induce target preheat due to the leading part of the laser pulse. Estimates of such preheat in these conditions suggest that it should modify by less than 10 % the ion beam parameters compared to the case of a unheated target.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
