V = 1 / n , the specific volume.
b) viscid case
to allow long term simulations: inclusion of an ion viscosity term
accounting for anomalous plasma transport
(keywords: plasma turbulence due to multiple ion streaming after the
collapse event, coarse-grained ion Vlasov distribution function)
~ supersonic propagation of a
peaked ion density front, the peak
being a remnant of the density collapse [2,3]
~ essentially 3 phases of evolution can be distinguished :
i) initial phase up to ion density bunching
ii) a stable peaked ion density front propagating with constant
velocity supersonically towards vacuum
iii) decay of the leading density hump due to debunching and
further acceleration of the resultant tiny ion front up to a
value determined by self-similar theory [2,3]
NUMERICAL SUBTLETIES :
~ exact numerical treatment of ion dynamics by a Lagrangian code [1,2]
~ need for a Poisson solver of high resolution and fast convergence of
the iteration procedure [1,2]
~ tri-diagonal coefficient matrix for the discretized evolution equations
with open (i.e. differential) boundary conditions [1,2]
