Complex Systems of Charged Particles and their Interactions with Electromagnetic Radiation 2016
ION ACCELERATION BY SLOW LIGHT FROM HETEROGENEOUS LOWDENSE
TARGETS
V. Yu. Bychenkov, A.V. Brantov, E.A. Govras, P. A. Ksenofontov*
*P. N. Lebedev Physics Institute, Russian Academy of Science, Moscow, Russia, e-mail:
[email protected] Center for Fundamental and Applied Research, VNIIA, ROSATOM, Moscow 127055, Russia
The study of ion acceleration from low-density targets revealed a new regime of ion acceleration by slow light [1]. It characterized by ion trapping in a laser ponderomotive sheath field of the relativistic laser pulse which penetrates into a near-critical-density plasma, strongly slows, and then increases its group velocity during propagation within a target. For a 30-J 30-fs laser pulse incident on a low-density homogeneous target, synchronization of the laser group velocity increase and the rate of proton acceleration by the ponderomotive sheath results in forming a proton beam with a maximum energy of 440 MeV, which is twice the energy obtained from a solid dense thin foil of optimal thickness.
In this work we describe synchronized ion acceleration by ultraintense light from heterogeneous targets. The specially chosen target density profile allows one to improve ions synchronization with the ponderomotive sheath to increase efficiency of ion acceleration inside targets.
This work was supported by the Russian Science Foundation (grant 14-12-00194). References
[1] Brantov A. V., Govras E. A., Kovalev V. F., Bychenkov V. Yu., Phys. Rev. Lett , 2016, 116, 085004