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Conditions and applicability limits of a new method for formation of quasi-monochromatic, with a large solid angle of divergence, linear X-ray fluxes from laser-produced plasmas are considered. The method is based on a special combination of laser target elements and -absorption filters, when the spectra of [H]- and [He]-like ions are excited in laser-produced plasma and -absorption filters select only the resonance lines of these ions from the linear spectrum. Experimental and theoretical studies have shown that, in the fluxes formed, the degree of monochromatisation may reach at the radiation contrast ratio of 5 – 10 and angular divergence of .

The results of investigation of a capillary discharge plasma, used as a source of intense VUV radiation and soft X-rays, are presented. The plasma was generated during the discharge of low-inductance condensers in a gas-filled ceramic capillary. Intense line radiation was observed in a broad spectral range (30-400 A) in various gases (CO2, Ne, Ar, Kr, Xe). The absolute radiation yield for the xenon discharge was ~5 mJ (2π sr)-1 pulse-1 within a spectral band of width 9 A at 135 A. Such a radiation source can be used for various practical applications, such as EUV projection lithography, microscopy of biological objects in a 'water window', reflectometry, etc.

New focusing short-period multilayer structures are developed which opens up wide possibilities for X-ray and VUV spectroscopy. Multilayer structures are deposited on a flat surface of a mica crystal which is then bent to a small-radius cylinder. The use of this structure in a von Hamos spectrometer for X-ray laser plasma diagnostics is demonstrated.

A description is given of a simple luminescent detector of radiation in the VUV range (10–100 nm) and of a method for absolute calibration of the sensitivity (quantum efficiency) of this detector. The detector and multilayer normal-incidence mirrors were used in determination of the absolute yield of the radiation from a laser plasma and in absolute calibration of the UF-4 photographic film at the wavelength of 18 nm.

Multilayer mirror optics was used in a pulse-periodic laser-plasma source of quasimonochromatic polarised x-rays. A calculation was made of the reflectivity and polarisability of multilayer mirrors at wavelengths λ = 17–18 nm. The experimental results were compared with calculations.

Experimental data and theoretical calculations are presented for X-ray spectra from a laser-produced plasma interacting with a solid surface and are compared with those obtained from the hot-burst core of the plasma. Intensities of the spectral lines of the principal series of the H-like and He-like magnesium ions were investigated. A close study of the resonance and intercombination lines was carried out with high spectral resolution in both regions of the intense X-ray emission: near the target and near the obstacle. The plasma near the target has an electron temperature of Te=500-700 eV and an electron density of Ne=1020-1021 cm-3, whereas near the obstacle Te=70-100 eV and Ne=2*1019-3*1019 cm-3. It is shown that the X-ray emission of high-Z ions from the near-obstacle plasma results from the three-body recombination followed by cascade transitions due to collisional and radiative processes.

A comparison is made between measured and calculated distribution of ionization stages in high-temperature low- (Tokamak) and high-density (laser produced) plasmas. The relative abundances of ionization species were derived from the dielectronic satellite spectra of Fe XXV-XVIII in the region λ = 1.85-1.95 A. New calculations for ionization balance included effects of autoionization accompanied by excitation of doubly-excited states of recombining ion and density-dependence of the dielectronic recombination rate were carried out. The results differ considerably from those of previous calculations which took into account these effects (Jacobs et al. [25]) as well as earlier ones made by Jordan [19]. There is a satisfactory agreement between the experimental ion concentration measured in laser plasmas and that predicted for the electron temperature Te = 1.3 × 107 K, ionization temperature Tz = 7.6 × 106 K and density Ne ≈ 1021-22 cm-1; transient or "quasi-steady-state" conditions are observed (Te ≠ Tz). In the low-density Tokamak plasma obtained by Hill et al. [5] an ionization equilibrium was found to exist at the ionization temperature Tz = Te.