Shock ignition of direct-drive double-shell targets

Shock ignition is investigated for non-cryogenic direct-drive double-shell targets. The fuel assembly is obtained by direct laser light absorbed in the external shell. The latter implodes and impacts the inner shell. The ignition is produced by a spherically convergent shock launched by a laser spike added at the end of the main laser drive. Analyses are carried out with and without a correction for the fuel assembly laser pulse. The correction is made by lowering the assembling laser pulse in order to maintain the implosion velocity constant when the ignitor spike is added. The results indicate that a moderate thermonuclear gain (~2 for spike power in the range 100–250 TW) can be achieved while the ignition threshold is displaced towards lower laser energies. The thermonuclear yield is tuned by the power in the spike which is a free parameter. A better gain is obtained when the main drive laser pulse is not corrected due to the dual effect of the increases in implosion velocity and in the DT ion temperature when the ignitor shock collapses.

[1]  Guy Schurtz,et al.  Shock ignition: an alternative scheme for HiPER , 2008 .

[2]  L. Perkins,et al.  Shock ignition of thermonuclear fuel with high areal density. , 2006, Physical review letters.

[3]  N Lecler,et al.  Target design for ignition experiments on the laser Mégajoule facility , 2006 .

[4]  O. Landen,et al.  The physics basis for ignition using indirect-drive targets on the National Ignition Facility , 2004 .

[5]  L. Perkins,et al.  An indirect-drive non-cryogenic double-shell path to 1ω Nd-laser hybrid inertial fusion–fission energy , 2010 .

[6]  Peter A. Amendt,et al.  Assessing the prospects for achieving double-shell ignition on the National Ignition Facility using vacuum hohlraums , 2007 .

[7]  S. Laffite,et al.  Design of an ignition target for the laser megajoule, mitigating parametric instabilities , 2010 .

[8]  Peter A. Amendt,et al.  Multimode short-wavelength perturbation growth studies for the National Ignition Facility double-shell ignition target designs , 2004 .

[9]  V Yu Glebov,et al.  Hohlraum-driven ignitionlike double-shell implosions on the omega laser facility. , 2005, Physical review letters.

[10]  L. Perkins,et al.  Shock ignition: a new approach to high gain inertial confinement fusion on the national ignition facility. , 2009, Physical review letters.

[11]  B. Canaud,et al.  High-gain shock ignition of direct-drive ICF targets for the Laser Mégajoule , 2010 .

[12]  B. Canaud,et al.  Optimization of laser–target coupling efficiency for direct drive laser fusion , 2005 .

[13]  Peter A. Amendt,et al.  Indirect-Drive Noncryogenic Double-Shell Ignition Targets for the National Ignition Facility: Design and Analysis , 2001 .

[14]  Stefano Atzeni,et al.  High-gain direct-drive target design for the Laser Mégajoule , 2004 .

[15]  M. Houry,et al.  Neutron and photon emission of a high-gain direct-drive target for laser fusion , 2006 .

[16]  N Lecler,et al.  High-gain direct-drive laser fusion with indirect drive beam layout of Laser Mégajoule , 2007 .

[17]  M J Bono,et al.  Hohlraum-driven mid-Z (SiO2) double-shell implosions on the omega laser facility and their scaling to NIF. , 2009, Physical review letters.

[18]  J. P. Watteau,et al.  Laser program development at CEL-V: overview of recent experimental results , 1986 .

[19]  B. Canaud,et al.  Ab initio determination of thermal conductivity of dense hydrogen plasmas. , 2009, Physical review letters.

[20]  M. Houry,et al.  High-gain direct-drive inertial confinement fusion for the Laser Mégajoule: recent progress , 2007 .

[21]  Joyce A. Guzik,et al.  Direct drive double shell target implosion hydrodynamics on OMEGA using offset pointing , 2004 .

[22]  J. Meyer-ter-Vehn,et al.  The physics of inertial fusion - Hydrodynamics, dense plasma physics, beam-plasma interaction , 2004 .

[23]  B. Canaud,et al.  Laser Mégajoule irradiation uniformity for direct drive , 2002 .