Laser-driven shock acceleration of ion beams from spherical mass-limited targets.
We report on experimental studies of ion acceleration from spherical targets of diameter 15 microm irradiated by ultraintense (1x10(20) W/cm2) pulses from a 20-TW Ti:sapphire laser system. A highly directed proton beam with plateau-shaped spectrum extending to energies up to 8 MeV is observed in the laser propagation direction. This beam arises from acceleration in a converging shock launched by the laser, which is confirmed by 3-dimensional particle-in-cell simulations. The temporal evolution of the shock-front curvature shows excellent agreement with a two-dimensional radiation pressure model.
Henig
A
A
Max-Planck-Institut für Quantenoptik, Garching, Germany. andreas.henig@mpq.mpg.de
Kiefer
D
D
Geissler
M
M
Rykovanov
S G
SG
Ramis
R
R
Hörlein
R
R
Osterhoff
J
J
Major
Zs
Z
Veisz
L
L
Karsch
S
S
Krausz
F
F
Habs
D
D
Schreiber
J
J