Experimental studies of direct-drive, low-intensity, low-adiabat spherical implosions on OMEGA

Journal Article · Thu Feb 15 04:00:00 EST 2007 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.2436752· OSTI ID:20974839

Smalyuk, V A; Betti, R; Delettrez, J A; Glebov, V Yu; Goncharov, V N; Li, D Y; Meyerhofer, D D; Regan, S P; Roberts, S; Sangster, T C; Stoeckl, C; Seka, W; Frenje, J A; Li, C K; Petrasso, R D; Seguin, F H ^[1]

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1. Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States)

Low-adiabat (high-compressibility) implosions were performed with {approx}860 {mu}m diam, 24- and 35-{mu}m-thick shells filled with 15 atm of D{sub 2} gas driven with {approx}12.5 kJ, 3-ns-square pulse shapes, and a laser intensity of {approx}2x10{sup 14} W/cm{sup 2}. Initial target modulations, imprinted on the target surface by laser nonuniformities, were varied by using drive with and without smoothing by spectral dispersion. The performance of the spherical implosions (with a gas fuel convergence of {approx}16) was correlated with measured target modulations at the end of the acceleration phase performed in a planar target with similar conditions using through-foil radiography. The neutron yield decreases sharply when target modulations become comparable with the target thickness at the end of the acceleration phase. The measured target areal densities are less sensitive to target modulations. Implosions with 35-{mu}m-thick shells produced neutron-averaged areal densities that are among the highest on OMEGA [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)].

• OSTI ID: 20974839
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 2 Vol. 14; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCELERATION
COMPRESSIBILITY
DEUTERIUM
GAS FUELS
IMPLOSIONS
LASERS
MODULATION
NEUTRONS
PERFORMANCE
PLASMA
PLASMA DENSITY
PLASMA DIAGNOSTICS
PLASMA PRODUCTION
PULSE SHAPERS
SPHERICAL CONFIGURATION