  Laser-produced plasma (LPP) induced during irradiation of a liquid tin
droplet with diameter of 150 um and 180 um by CO2 laser pulse with various
pulse durations and energies is considered. The two-dimensional radiative
magnetohydrodynamic (RMHD) plasma code is used to simulate the emission and
plasma dynamics of multicharged ion tin LPP. Results of simulations for various
laser pulse durations and 75-600 mJ pulse energies with Gaussian and
experimentally taken temporal profiles are discussed. It is found that if the
mass of the target is big enough to provide the plasma flux required (the
considered case) a kind of dynamic quasi-stationary plasma flux is formed. In
this dynamic quasi-stationary plasma flux, an interlayer of relatively cold tin
vapor with mass density of 1-2 g/cm3 is formed between the liquid tin droplet
and low density plasma of the critical layer. Expanding of the tin vapor from
the droplet provides the plasma flux to the critical layer. In critical layer
the plasma is heated up and expands faster. In the simulation results with
spherical liquid tin target, the CE into 2${\pi}$ is of 4% for 30 ns FWHM and
just slightly lower - of 3.67% for 240 ns FWHM for equal laser intensities of
14 GW/cm2. This slight decay of the in-band EUV yield with laser pulse duration
is conditioned by an increasing of radiation re-absorption by expanding plasma
from the target, as more cold plasma is produced with longer pulse. The
calculated direction diagrams of in-band EUV emission permit to optimize a
collector configuration.
