Back to Search
Start Over
Cryogenic-target performance and implosion physics studies on OMEGA.
- Source :
- Physics of Plasmas; May2009, Vol. 16 Issue 5, p056301, 8p, 2 Diagrams, 7 Graphs
- Publication Year :
- 2009
-
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/cm<superscript>2</superscript> in cryogenic D<subscript>2</subscript> implosions with peak laser-drive intensities of ∼5×10<superscript>14</superscript> W/cm<superscript>2</superscript> were previously reported [T. C. Sangster et al., Phys. Rev. Lett. 100, 185006 (2008)]. The laser intensity is increased to ∼10<superscript>15</superscript> W/cm<superscript>2</superscript> to demonstrate ignition-relevant implosion velocities of 3–4×10<superscript>7</superscript> 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 ∼10<superscript>15</superscript> W/cm<superscript>2</superscript>. 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 ∼10<superscript>15</superscript> W/cm<superscript>2</superscript>. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 1070664X
- Volume :
- 16
- Issue :
- 5
- Database :
- Complementary Index
- Journal :
- Physics of Plasmas
- Publication Type :
- Academic Journal
- Accession number :
- 40637954
- Full Text :
- https://doi.org/10.1063/1.3078102