Vlasov approximation

The approximation where we ignore 0 " and keep 0 can be solved exactly. This approximation corresponds to a generalized random-phase approximation or a linearized Vlasov approximation where the bare potential V(r) is replaced by — Co(r). Since 0 does not take into account any damping... 

The situation is similar to the one encountered in the kinetic theory of dilute plasmas. 510 To lowest order in the density+) the one-particle distribution function of the electrons obeys the Vlasov equation. The next order approximation consists of two coupled equations for the one-particle and two-particle distribution functions. On the other hand, in the kinetic theory of gases Bogolyubovft) has proposed an... 

Figure 7. Dipole signal along the direction of laser polarization (Dz, upper part) and number of emitted electrons (Nesc, lower part) as a function of time during the interaction of a femtosecond laser pulse withNaJ. The laser frequency and fluency are = 2,7oeV and J = 6 10uW/cm2, and the pulse envelope is indicated in dashed line. Both Vlasov and VUU results arc plotted for comparison. Ionic background is treated in the soft jellium approximation. From [44],...

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