Iodine photodissociation laser pulse(λ=1.32㎛, pulse width=13.3ns) is focussed to various targets (C,Al,Ti,Fe,Cu,Mo) and laser plasma is produced. Two electron temperature are obtained from the two slopes of continuous x-ray spectra over the region (0＜λ＜19.8A). Z-dependence of two electron temperatures (6＜Z＜42) are disscused from the characteristics of the plasma heating processes to which the long pulse laser beam is involved. One dimensional hydrodynamic model for the plasma electrons is used and the time-averaged temperature is derived theoretically to explain the cold electron temperature $T_c$ obtained experimentally. Also, the hot electron temperature $T_h$ obtain experimentally is explained by the effect of parametric instability.
As an application of laser plasma, soft x-ray contact microscopy have been tried. For he high x-ray conversion efficiency, $M_0$ target is used and two type's x-ray resists (PMMA and PBS) are used to make the replica of specimen's image. PBS is found to be more sensitive and appropriate for our laser plasma x-ray sources. Various biological specimens have been tried such as spider's threads, human red blood cells, E.coli. From the magnification of SEM image, resolution of 2000A is obtained. $F_0$ the furtupe, more high resolution of x-ray images expected by using focussing x-ray optics such as grazing incidence iirror
