J. Plasma Physics (2006), vol. 72, part 6, pp. 791–794. c  2006 Cambridge University Press doi:10.1017/S0022377806004892 Printed in the United Kingdom 791 The formation of high-density core plasma in non-spherical implosion using high-resolution two-dimensional integrated implosion code H. NAGATOMO 1 , T. JOHZAKI 1 , A. SUNAHARA 2 and K. MIMA 1 1 Institute of Laser Engineering, Osaka University, 2-6 Yamadaoka Suita, Osaka 565-0871, Japan 2 Institute for Laser Technology, 2-6 Yamadaoka Suita, Osaka 565-0871, Japan (Received 18 August 2005 and accepted 9 December 2005) Abstract. Fast ignition is an epoch-making scheme for inertial fusion energy. In this scheme, the formation of high-density core plasma is one of the key issues which must be solved, because the implosion dynamics of the fast ignition target, which is non-spherical with a conical target, is quite different from that of the conventional central ignition target. Some previous works showed the possibility of formation of a high-density core. However, the effects of hydrodynamic instability were not discussed in those works. In this paper, we simulate the whole implosion dynamics of a perturbed non-spherical target, and the effect of radiation transport instability is estimated using the two-dimensional integrated implosion (radiation hydrodynamics) code PINOCO. In the result, we have found that the hydrodynamic instabily has less of an effect on the formation of high-density core plasma in the cone-guided implosion, in comparision with the spherical implosion. 1. Introduction The fast ignition scheme is one of the most fascinating and feasible ignition schemes for inertial fusion energy [1, 2]. Numerical simulation plays an important role in demonstrating the performance of fast ignition, designing the targets and op- timizing laser pulse shapes for the scheme. One of the key issues in fast ignition is controlling the implosion dynamics to form high-density core plasma in non- spherical implosion. Some previous works showed the possibility of formation of a high-density core plasma [3]. However, in those simulations, the non-uniformity of the initial target or laser irradiation are not included, and the effects of hy- drodynamic instability were not discussed. Therefore, preliminary simulations are performed to demonstrate the effect of radiation transport (RT) instability, which is seeded by the perturbation on the initial target surface. It may be difficult to simulate the problem with a conventional Lagrangian-based implosion code for the rezoning/remapping problem. Here, a two-dimensional integrated implosion code, PINOCO, is applied for the simulations. In this code, almost all of the physics models which are required to simulate the laser-driven implosion are included. In this paper, an outline of PINOCO is given briefly, and we discuss the simulated results of cone-guided implosion with/without initial perturbation on the target surface.