Efficiency of conical targets for laser thermonuclear fusion

The advantages and disadvantages of conical targets for laser thermonuclear fusion are considered. An analysis is made of the possibility of reducing the laser power, extending the laser pulse, and increasing the neutron yield, using an ideal conical target with absolutely rigid walls of zero thermal conductivity, compared with a spherical target of equal mass. A simple theory is proposed enabling the influence of the walls on the fusion process in a conical target with a gaseous fuel and a heavy shell to be taken into account. Estimates are given of the energy losses caused by distortion of the walls and heat conduction in them. The influence of these effects on the neutron yield is estimated.