9 research outputs found
The national ignition facility: Path to ignition in the laboratory
The National Ignition Facility (NIF) is a 192-beam laser
facility presently under construction at LLNL. When completed, NIF will be a
1.8-MJ, 500-TW ultraviolet laser system. Its missions are to obtain fusion
ignition and to perform high energy density experiments in support of the
U.S. nuclear weapons stockpile. Four of the NIF beams have been commissioned
to demonstrate laser performance and to commission the target area including
target and beam alignment and laser timing. During this time, NIF
demonstrated on a single-beam basis that it will meet its performance goals
and demonstrated its precision and flexibility for pulse shaping, pointing,
timing and beam conditioning. It also performed four important experiments
for Inertial Confinement Fusion and High Energy Density Science. Presently,
the project is installing production hardware to complete the project in
2009 with the goal to begin ignition experiments in 2010. An integrated plan
has been developed including the NIF operations, user equipment such as
diagnostics and cryogenic target capability, and experiments and
calculations to meet this goal. This talk will provide NIF status, the plan
to complete NIF, and the path to ignition
Hard X-ray and hot electron environment in vacuum hohlraums at NIF
Time resolved hard x-ray images (hv 9 keV) and time
integrated hard x-ray spectra (hv 18-150 keV) from vacuum hohlraums
irradiated with four 351 nm wavelength NIF laser beams are presented as a
function of hohlraum size and laser power and duration. The hard x-ray
images and spectra provide insight into the time evolution of the hohlraum
plasma filling and the production of hot electrons. The fraction of laser
energy detected as hot electrons (f shows correlation with both
laser intensity and with an analytic plasma filling model
Krasnoselskii type fixed point theorems for multi-valued mappings with weakly sequentially closed graph
Culture and differentiation of cytokine-induced killer cells from umbilical cord blood-derived mononuclear cells
Laser coupling to reduced-scale targets at NIF Early Light
Deposition of maximum laser energy into a small, high-Z enclosure in a short laser pulse creates a hot environment. Such targets
were recently included in an experimental campaign using the first four of
the 192 beams of the National Ignition Facility [J. A. Paisner, E. M.
Campbell, and W. J. Hogan, Fusion Technology 26, 755 (1994)], under
construction at the University of California Lawrence Livermore National
Laboratory. These targets demonstrate good laser coupling, reaching a
radiation temperature of 340 eV. In addition, the Raman backscatter spectrum
contains features consistent with Brillouin backscatter of Raman forward
scatter [A. B. Langdon and D. E. Hinkel, Physical Review Letters 89, 015003 (2002)]. Also,
NIF Early Light diagnostics indicate that 20% of the direct backscatter
from these reduced-scale targets is in the polarization orthogonal to that
of the incident light