Fast ignition (FI) of a deuterium–tritium target compressed to a density of 500 g cm−3 by the energy deposition of two laser-accelerated proton beams is studied by two-dimensional (2D) and three-dimensional (3D) numerical simulations. The first proton beam has an annular radial profile while the second beam is cylindrical. Both beams are characterized by a super-Gaussian profile in radius. A 3D-hydrodynamic study has been performed to identify a way to generate a nearly annular energy deposition by using a discrete number of cylindrical beams. It has been found that the energy deposited by the first proton beam can modify the density and temperature of the plasma before the arrival of the second beam allowing ignition in a zone not directly irradiated by the beams. Thus, differently from the classical FI concept, fuel ignition is not a direct consequence of plasma heating by the particle beam. Indeed, ignition occurs as a result of the synergetic action of the shocks generated by proton energy deposition.
Fast ignition induced by skocks generated by laser-accelerated proton beams / M., Temporal; R., Ramis; J. J., Honrubia; Atzeni, Stefano. - In: PLASMA PHYSICS AND CONTROLLED FUSION. - ISSN 0741-3335. - STAMPA. - 5:(2009), p. 035010. [10.1088/0741-3335/51/3/035010]
Fast ignition induced by skocks generated by laser-accelerated proton beams
ATZENI, Stefano
2009
Abstract
Fast ignition (FI) of a deuterium–tritium target compressed to a density of 500 g cm−3 by the energy deposition of two laser-accelerated proton beams is studied by two-dimensional (2D) and three-dimensional (3D) numerical simulations. The first proton beam has an annular radial profile while the second beam is cylindrical. Both beams are characterized by a super-Gaussian profile in radius. A 3D-hydrodynamic study has been performed to identify a way to generate a nearly annular energy deposition by using a discrete number of cylindrical beams. It has been found that the energy deposited by the first proton beam can modify the density and temperature of the plasma before the arrival of the second beam allowing ignition in a zone not directly irradiated by the beams. Thus, differently from the classical FI concept, fuel ignition is not a direct consequence of plasma heating by the particle beam. Indeed, ignition occurs as a result of the synergetic action of the shocks generated by proton energy deposition.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.