Proton beams laser accelerated from thin foils are studied for various plasma gradients on the foil rear surface. The beam maximum energy and spectral slope reduce with the gradient scale length, in good agreement with numerical simulations. The results also show that the j×B mechanism determines the temperature of the electrons driving the ion expansion. Future ion-driven fast ignition of fusion targets will use multikilojoule petawatt laser pulses, the leading part of which will induce target preheat. Estimates based on the data show that this modifies by less than 10% the ion beam parameters.
Laser-foil acceleration of high-energy protons in small scale plasma gradients / J., Fuchs; C. A., Cecchetti; M., Borghesi; T., Grismayer; Antici, Patrizio; Atzeni, Stefano; P., AUDEBERT P; E., D'Humieres; P., Mora; A., Pipahl; L., Romagnani; Schiavi, Angelo; Y., Sentoku; T., Toncian; O., Willi. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - STAMPA. - 99:(2007), p. 015002. [10.1103/PhysRevLett.99.015002]
Laser-foil acceleration of high-energy protons in small scale plasma gradients
ANTICI, PATRIZIO;ATZENI, Stefano;SCHIAVI, ANGELO;
2007
Abstract
Proton beams laser accelerated from thin foils are studied for various plasma gradients on the foil rear surface. The beam maximum energy and spectral slope reduce with the gradient scale length, in good agreement with numerical simulations. The results also show that the j×B mechanism determines the temperature of the electrons driving the ion expansion. Future ion-driven fast ignition of fusion targets will use multikilojoule petawatt laser pulses, the leading part of which will induce target preheat. Estimates based on the data show that this modifies by less than 10% the ion beam parameters.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
