Speaker
Wanli Shang
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P1.2026.pdf
Hot-spot emission properties in a warm plastic-shell implosion on
OMEGA
W.L. Shang1, C. Stoeckl2, R. Betti2, S.P. Regan2, T.C. Sangster2, S.X. Hu2, A.
Christopherson2, V. Gopalaswamy2, D. Cao2, W. Seka2, D.T. Michel2,
A.K. Davis2, P.B. Radha2, F.J. Marshall2, R. Epstein2, A.A. Solodov2
1
Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang
621900 China
2
Laboratory for Laser Energetics, University of Rochester, Rochester NY 14623
A warm plastic-shell implosion was performed on the OMEGA laser system. The measured
corona plasma evolution and shell trajectory in the acceleration phase are reasonably
simulated by the one-dimensional LILAC simulation including the nonlocal and cross-beam
energy transfer models. The results from analytical thin-shell model reproduce the
time-dependent shell radius by LILAC simulation, and also the hot-spot x-ray emissivity
profile at stagnation predicted by Spect3D. In the Spect3D simulations within a clean
implosion, a “U”-shaped hot-spot radius evolution can be observed with the
Kirkpatrick-Baez microscope response (the photon energy is from 4 to 8 keV). However, a
fading away hot-spot radius evolution was measured in OMEGA warm plastic-shell
implosion because of mixings. The distance from the measured hot-spot radius evolution
shape to the “U” shape could be a new criterion for an experimental implosion performance.
To recover the measured hot-spot x-ray emissivity profile at stagnation, a non-isobaric
hot-spot model is built, and the normalized hot-spot temperature, density, and pressure
profiles (normalized to the corresponding target-center values) are obtained.
References:
[1] V. N. Goncharov, T. C. Sangster, R. Betti, T. R. Boehly et al., Phys. Plasmas 21, 056315
(2014).
[2] P. B. Radha, J. Delettrez, R. Epstein, V. Yu Glebov, R. Keck et al., Phys. Plasmas 9, 2208
(2002).
