The linear stability of an ablating plasma is investigated as an eigenvalue problem by assuming the plasma to be at the stationary state. For various structures of the ablating plasma, the growth rate is found to be expressed well in the form γ=α(kg)1/2 −βkVa, where α=0.9, β≂3–4, and Va is the flow velocity across the ablation front, and is found to agree well with recent two‐dimensional simulations in a classical transport regime. Short‐wavelength lasers inducing enhanced mass ablation are suggested to be advantageous to stable implosion because of the ablative stabilization.

1.
G. W. Fraley, W. P. Gula, D. B. Henderson, R. L. McCrory, R. C. Malone, R. J. Mason, and R. L. Morse, in Plasma Physics and Controlled Nuclear Fusion Research (IAEA, Vienna, 1974), Vol. II, p. 543.
2.
R. L.
McCrory
,
L.
Montierth
,
R. L.
Morse
, and
C. P.
Verdon
,
Phys. Rev. Lett.
46
,
336
(
1981
).
3.
C. P.
Verdon
,
R. L.
McCrory
,
R. L.
Morse
,
G. R.
Baker
,
D. I.
Meiron
, and
S. A.
Orszag
,
Phys. Fluids
25
,
1653
(
1982
).
4.
R. L. McCrory, L. Montierth, R. L. Morse, and C. P. Verdon, in Laser Interaction and Related Plasma Phenomena (Plenum, New York, 1981), Vol. 5, pp. 713–742.
5.
H.
Takabe
,
L.
Montierth
, and
R. L.
Morse
,
Phys. Fluids
26
,
2299
(
1983
).
6.
M. H.
Emery
,
J. H.
Gardner
, and
J. P.
Boris
,
Appl. Phys. Lett.
41
,
808
(
1982
);
also see M. H. Emery, J. H. Gardner, and J. P. Boris, submitted to Appl. Phys. Lett. errata.
7.
M. H.
Emery
,
J. H.
Gardner
, and
J. P.
Boris
,
Phys. Fluids
27
,
1338
(
1984
).
8.
L.
Baker
,
Phys. Fluids
26
,
627
(
1983
).
9.
D. G.
Colombant
and
W. M.
Manheimer
,
Phys. Fluids
26
,
3127
(
1983
).
10.
W. M.
Manheimer
and
D. G.
Colombant
,
Phys. Fluids
27
,
983
(
1984
).
11.
D. L.
Book
and
I. B.
Bernstein
,
J. Plasma Phys.
23
,
521
(
1980
).
12.
J. L.
Bobin
,
Phys. Fluids
14
,
2341
(
1971
).
13.
H.
Takabe
,
K.
Nishihara
, and
T.
Taniuti
,
J. Phys. Soc. Jpn.
45
,
2001
(
1978
).
14.
W. L.
Manheimer
,
D. G.
Colombant
, and
J. H.
Gardner
,
Phys. Fluids
25
,
1644
(
1982
).
15.
In the moving frame in spherical geometry, additional terms stemming from the dependence of divergence on the radius should be included in Eqs. (4) and (5). That is, when we transfer the coordinate as r = r0+∫0tvfdt, where vf is the velocity of the frame and vf = −gt in the present model, the divergence of a variable f is (1/r2)(∂/∂r)(r2f) = (1/r02)(∂/∂r)(r02f)+[(2/r)−(2/r0)]f. Strictly speaking, therefore, the stationary state does not exist in spherical geometry for vf≠0. However, under the condition that 2(r−1−r0−1)≪(1/f)(∂f/∂r0)≡1/Lf, where Lf is typical scale length of the plasma, the neglect of the additional terms can be assumed. In fact, the condition is satisfied since the nonlinear electron heat flow makes the plasma accompany the steep density, velocity, and temperature gradients.
16.
S. J.
Gitomer
,
R. L.
Morse
, and
B. S.
Newberger
,
Phys. Fluids
20
,
234
(
1977
);
L. Montierth and R. L. Morse, submitted to Phys. Fluids.
17.
I. B.
Bernstein
and
D. L.
Book
,
Phys. Fluids
,
26
,
453
(
1983
).
18.
S.
Bodner
,
Phys. Rev. Lett.
33
,
761
(
1974
).
19.
W. M.
Manheimer
and
D. G.
Colombant
,
Phys. Fluids
27
,
1927
(
1984
).
20.
S. Bodner, M. Emery, J. Gardner, J. Grun, M. Herbst, S. Kacenjar, R. Lehmberg, C. Manka, E. McLean, S. Obenschain, B. Ripin, A. Schmitt, J. Stamper, and F. Yang, in Plasma Physics and Controlled Nuclear Fusion Research, 10th International Conference London, 1984 (IAEA, Vienna, 1985), Vol. 3, p. 155.
21.
B.
Ahlborn
,
M. H.
Key
, and
A. R.
Bell
,
Phys. Fluids
25
,
541
(
1982
).
22.
S. Skupsky, R. L. McCrory, R. S. Craxton, J. Delettrez, R. Epstein, K. Lee, and C. Verdon (private communication).
23.
M. H.
Emery
,
J. H.
Orens
,
J. H.
Gardner
, and
J. P.
Boris
,
Phys. Rev. Lett.
48
,
253
(
1982
).
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