Observation of the parametric two-ion decay instability with thomson scattering.
We present the first direct experimental observation of the parametric two-ion decay instability of ion-acoustic waves driven by a high intensity (5 x 10(15) W cm(-2)) laser beam in a laser produced high-Z plasma. Using two separate Thomson scattering diagnostics simultaneously, we directly measure the scattering from thermal ion-acoustic fluctuations, the primary ion waves that are driven to large amplitudes by the high intensity beam, and the two-ion decay products. The decay products are shown to be present only where the interaction takes place and their k spectrum is broad.
Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA.
C
C
Niemann
S H
SH
Glenzer
J
J
Knight
L
L
Divol
E A
EA
Williams
G
G
Gregori
B I
BI
Cohen
C
C
Constantin
D H
DH
Froula
D S
DS
Montgomery
R P
RP
Johnson