B. J. Macgowan

Learn More
Backscattered light via laser-plasma instabilities has been measured in early NIF hohlraum experiments on two beam quads using a suite of detectors. A full aperture backscatter system and near backscatter imager (NBI) instrument separately measure the stimulated Brillouin and stimulated Raman scattered light. Both instruments work in conjunction to(More)
Timber harvesting has been shown to have both positive and negative effects on forest dwelling species. We examined the immediate effects of timber harvests (clearcuts and group selection openings) on ectotherm behavior, using the eastern box turtle as a model. We monitored the movement and thermal ecology of 50 adult box turtles using radiotelemetry from(More)
R. K. Kirkwood,1 D. S. Montgomery,2 B. B. Afeyan,3 J. D. Moody,1 B. J. MacGowan,1 C. Joshi,4 K. B. Wharton,4 S. H. Glenzer,1 E. A. Williams,1 P. E. Young,1 W. L. Kruer,1 K. G. Estabrook,1 and R. L. Berger1 1University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 2Los Alamos National Laboratory, Los Alamos,(More)
The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray(More)
The generation of neutron/gamma radiation, electromagnetic pulses (EMP), debris and shrapnel at mega-Joule class laser facilities (NIF and LMJ) impacts experiments conducted at these facilities. The complex 3D numerical codes used to assess these impacts range from an established code that required minor modifications (MCNP calculates neutron and gamma(More)
The National Ignition Facility NIF will provide up to 1.8 MJ of laser energy for imploding inertial confinement fusion ICF targets. Ignited NIF targets are expected to produce up to 1019 DT neutrons. This will provide unprecedented opportunities and challenges for the use of nuclear diagnostics in ICF experiments. In 2005, the suite of nuclear-ignition(More)
Indirect-drive hohlraum experiments at the National Ignition Facility have demonstrated symmetric capsule implosions at unprecedented laser drive energies of 0.7 megajoule. One hundred and ninety-two simultaneously fired laser beams heat ignition-emulate hohlraums to radiation temperatures of 3.3 million kelvin, compressing 1.8-millimeter-diameter capsules(More)
Theoretical calculations of a Thomson scattering cross section and dynamical form factors are presented for high-Z laser produced inhomogeneous plasmas. Relevance of these results to astrophysical plasmas is pointed out. Comparisons with recent experimental observations are discussed with emphasis on the effects of plasma inhomogeneity, ion-ion collisions(More)
conditions relevant to ignition R. K. Kirkwood, P. Michel, R. London, J. D. Moody, E. Dewald, L. Yin, J. Kline, D. Hinkel, D. Callahan, N. Meezan, E. Williams, L. Divol, B. L. Albright, K. J. Bowers, E. Bond, H. Rose, Y. Ping, T. L. Wang, C. Joshi, W. Seka, N. J. Fisch, D. Turnbull, S. Suckewer, J. S. Wurtele, S. Glenzer, L. Suter, C. Haynam, O. Landen, and(More)
Spatial filters are essential components for maintaining high beam quality in high-energy pulsed laser systems. The long-duration (21 ns) high-energy pulses envisioned for future inertial-confinement fusion drive systems, such as the U.S. National Ignition Facility (NIF), are likely to lead to increased plasma generation and closure effects within the(More)