TITLE

Cryogenic-target performance and implosion physics studies on OMEGA

AUTHOR(S)
Smalyuk, V. A.; Betti, R.; Boehly, T. R.; Craxton, R. S.; Delettrez, J. A.; Edgell, D. H.; Glebov, V. Yu.; Goncharov, V. N.; Harding, D. R.; Hu, S. X.; Knauer, J. P.; Marshall, F. J.; McCrory, R. L.; McKenty, P. W.; Meyerhofer, D. D.; Radha, P. B.; Regan, S. P.; Sangster, T. C.; Seka, W.; Short, R. W.
PUB. DATE
May 2009
SOURCE
Physics of Plasmas;May2009, Vol. 16 Issue 5, p056301
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Recent progress in direct-drive cryogenic implosions on the OMEGA Laser Facility [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)] is reviewed. Ignition-relevant areal densities of ∼200 mg/cm2 in cryogenic D2 implosions with peak laser-drive intensities of ∼5×1014 W/cm2 were previously reported [T. C. Sangster et al., Phys. Rev. Lett. 100, 185006 (2008)]. The laser intensity is increased to ∼1015 W/cm2 to demonstrate ignition-relevant implosion velocities of 3–4×107 cm/s, providing an understanding of the relevant target physics. Planar-target acceleration experiments show the importance of the nonlocal electron-thermal-transport effects for modeling the laser drive. Nonlocal and hot-electron preheat is observed to stabilize the Rayleigh–Taylor growth at a peak drive intensity of ∼1015 W/cm2. The shell preheat caused by hot electrons generated by two-plasmon-decay instability was reduced by using Si-doped ablators. The measured compressibility of planar plastic targets driven with high-compression shaped pulses agrees well with one-dimensional simulations at these intensities. Shock mistiming has contributed to compression degradation of recent cryogenic implosions driven with continuous pulses. Multiple-picket (shock-wave) target designs make it possible for a more robust tuning of the shock-wave arrival times. Cryogenic implosions driven with double-picket pulses demonstrate somewhat improved compression performance at a peak drive intensity of ∼1015 W/cm2.
ACCESSION #
40637954

 

Related Articles

  • High performance silicon hot electron bolometers. Moseley, H.; McCammon, D. // AIP Conference Proceedings;2002, Vol. 605 Issue 1, p103 

    High performance Si bolometers can be made using the electron-phonon conductance in the heavily doped Si to provide thermal isolation from the cryogenic bath. Thermal conductance, response time, noise, and signal frequency resistance are predicted based on laboratory measurements of larger...

  • Hot-core assembly in cryogenic D2 direct-drive spherical implosions. Smalyuk, V. A.; Dumanis, S. B.; Delettrez, J. A.; Glebov, V. Yu.; Meyerhofer, D. D.; Regan, S. P.; Sangster, T. C.; Stoeckl, C. // Physics of Plasmas;Oct2006, Vol. 13 Issue 10, p104502 

    The temperature-density profiles of imploded cryogenic D2 capsules are inferred for a low-adiabat (α∼6) drive using a Monte Carlo technique described earlier [V. A. Smalyuk et al., Phys. Plasmas 12, 052706 (2005)]. The analysis has been improved by incorporating differential x-ray...

  • Dynamics of relativistic electrons propagating in a funnel-guided target. Zhou, C. T.; Wang, X. G.; Ruan, S. C.; Wu, S. Z.; Chew, L. Y.; Yu, M. Y.; He, X. T. // Physics of Plasmas;Aug2010, Vol. 17 Issue 8, p083103 

    Hot electron transport in a funnel-guided target is investigated using two-dimensional hybrid simulations. Relativistic electrons generated by a petawatt picosecond short-pulse laser interacting with a gold slab are guided by a funnel to the compressed core region of the fuel. It is shown that...

  • Trapping induced nonlinear behavior of backward stimulated Raman scattering in multi-speckled laser beams. Yin, L.; Albright, B. J.; Rose, H. A.; Bowers, K. J.; Bergen, B.; Kirkwood, R. K.; Hinkel, D. E.; Langdon, A. B.; Michel, P.; Montgomery, D. S.; Kline, J. L. // Physics of Plasmas;May2012, Vol. 19 Issue 5, p056304 

    In inertial confinement fusion experiments, stimulated Raman scattering (SRS) occurs when electron density fluctuations are amplified resonantly by the incident laser beams and scattered light. These beams comprise several thousands of individual laser speckles. We have found in single-speckle...

  • Multiple-pass laser beam deflection probe for detection of acoustic and weak shock waves in fluids. Diaci, Janez; Mozina, Janez // Review of Scientific Instruments;Sep95, Vol. 66 Issue 9, p4644 

    Examines a novel laser beam deflection arrangement for detection of acoustic and weak shock waves in fluids. Novelty of the arrangement; Interaction between the probed wave with several segments of the probing beam in sequence; Simple theoretical model that qualitatively explains the most...

  • Observations of modulated shock waves in solid targets driven by spatially modulated laser beams. Boehly, T. R.; Collins, T. J. B.; Gotchev, O.; Kessler, T. J.; Knauer, J. P.; Sangster, T. C.; Meyerhofer, D. D. // Journal of Applied Physics;8/1/2002, Vol. 92 Issue 3, p1212 

    The growth of surface perturbations due to nonuniformities in the drive laser is an important subject in laser-matter interactions. We present results of experiments using drive lasers with known, single-mode modulations to produce nonuniform shocks that propagate into planar plastic (CH)...

  • An analytical model for creation and decay of strong shock waves caused by a trapezoidal laser pulse. Loeb, A.; Eliezer, S. // Physics of Fluids (00319171);Apr85, Vol. 28 Issue 4, p1196 

    An analytic hydrodynamic model for the formation and decay of strong shock waves (0.1-10 TPa) is derived in this paper by using serf-consistent and well-defined assumptions. A trapezoidal pressure profile as a function of time applied to the target surface is used as the initial condition. This...

  • Ion acoustic instability driven by a temperature gradient in laser-produced plasmas. Brantov, A. V.; Bychenkov, V. Yu.; Rozmus, W. // Physics of Plasmas;Aug2001, Vol. 8 Issue 8 

    The return current instability excited in laser-produced plasmas by a temperature gradient has been studied using a nonlocal theory of electron transport. The transport model is applicable for an arbitrary ratio of the temperature inhomogeneity scale length to the collisional mean free path. It...

  • Shock induced Rayleigh–Taylor instability in the presence of a boundary layer. Houas, L.; Farhat, A.; Brun, R. // Physics of Fluids (00319171);Apr88, Vol. 31 Issue 4, p807 

    The aim of this work is an experimental study of the development of perturbations of a gaseous interface impulsively accelerated by a plane shock wave. The experiments are performed in a double diaphragm shock tube, where the second diaphragm is a very thin Mylar film which can be initially...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics