OMEGA polar-drive target designs
- Laboratory for Laser Energetics, University of Rochester, 250 E. River Road, Rochester, New York 14623 (United States)
Low-adiabat polar-drive (PD) [Skupsky et al., Phys. Plasmas 11, 2763 (2004)] implosion designs for the OMEGA [Boehly et al., Opt. Commun. 133, 495 (1997)] laser are described. These designs for cryogenic deuterium-tritium and warm plastic shells use a temporal laser pulse shape with three pickets followed by a main pulse [Goncharov et al., Phys. Rev. Lett. 104, 165001 (2010)]. The designs are at two different on-target laser intensities, with different in-flight aspect ratios (IFARs). These designs permit studies of implosion energetics and target performance closer to ignition-relevant intensities ({approx}7 Multiplication-Sign 10{sup 14} W/cm{sup 2} at the quarter-critical surface, where nonlocal heat conduction and laser-plasma interactions can play an important role) but at lower values of IFAR {approx} 22 or at lower intensity ({approx}3 Multiplication-Sign 10{sup 14} W/cm{sup 2}) but at a higher IFAR (IFAR {approx} 32, where shell instability can play an important role). PD geometry requires repointing of laser beams to improve shell symmetry. The higher-intensity designs optimize target performance by repointing beams to a lesser extent, compensating for the reduced equatorial drive by increasing the energies of the repointed beams. They also use custom beam profiles that improve equatorial illumination at the expense of irradiation at higher latitudes. These latter designs will be studied when new phase plates for the OMEGA Laser System, corresponding to the custom beam profiles, are obtained.
- OSTI ID:
- 22086050
- Journal Information:
- Physics of Plasmas, Vol. 19, Issue 8; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Polar-direct-drive simulations and experiments
Improving cryogenic deuterium–tritium implosion performance on OMEGA