[en] Full text: The process of plasma formation at moderate density laser radiation on a surface of a target is interconnected to destruction of the latter. Therefore various static and dynamic defects of various static targets can obviously influence efficiency of processes occurring at interaction of laser radiation with a target. We investigate influence of structural defects of a target on process of its interaction with neodymium laser radiation (l = 1.06μm). The structural defects in a studied sample are created by radiation reactor of 10¹⁵-10²⁰ neutrons /cm². Coronado was chosen as object of researches as it is possible to find out not only influence of structural defects created by neutrons, but also to estimate a role γ - component of reactor radiation. The radiation of a neodymium laser (pulse length τ ∼ 50 ns, pulse energy 3 J) was focused on the surface of a sample. The radiation intensity at the target surface (q) was varied by using neutral density filters between 1- 100 GW/cm². Electronic and ion currents were studied together with charge and power distributions of multiply charged ions scattered in structure of formed plasma. Measurement of electronic and ion currents was conducted by a collector method and the charge and energy characteristics of ions were analysed by the technique of time-of- flight mass spectrometry. The dominant role of structural defects, which influence the interaction efficiency, in modifying the properties of investigated targets was clearly demonstrated by the results obtained with an Al ₂O₃ target (corundum). For example, γ-ray irradiation of corundum of 10¹⁰ R, which does not induce structural disruptions in it, has no effect on the charge Z_max of Al and O ions. By contrast, when the laser radiation with the same q acts on a reactor-irradiated sample, the charge- state distributions of Al and O ions are broader than they are prior to reactor irradiation. In particular, when an unexposed Al₂ O₃ sample was irradiated at q =10¹¹ W cm^-2, Z_max for O and Al was respectively 4 and 3; when the target was per-exposed to a fluency 2.10¹⁸ neutrons /cm², the intensity of ion-produced signals recorded from plasma increased in comparison with the plasma of an unexposed sample while the charge- state spectrum itself was supplemented by the lines of O⁵⁺-O⁷⁺, Al⁴⁺ ions. The influence of structural disruptions is also confirmed by the results obtained on recovery annealing of reactor - irradiated corundum. When irradiating Al₂O₃ previously exposed to neutrons at the specified fluency and annealed for 1h at 6000 deg C, the ion charge state of the resultant plasma is somewhat lower than prior to annealing but higher than it was prior to neutron irradiation. If a sample thus annealed subsequently exposed to additional γ-irradiation with a dose up to 10⁸ R, the O⁵⁺-O⁷⁺ ions recorded as before in the plasma produced at q =10¹¹ W/cm². A comparison of the ion energy spectra of the plasma produced from a per- irradiated target and the plasma from an initial (unexposed) sample revealed that radiation processing of the sample to be studied is reflected in the regularities of ion formation. The energy distribution of the Al and O ions produced by irradiation of corundum previously exposed to γ-rays is identical to that observed with an unexposed Al₂O₃. An investigation of the energy spectra of the plasma origination from a reactor- irradiated target showed that ions with any Z value are characterized by distribution broadening owing to the addition of low- and high- energy ions with increase in the radiation dose. Apart from that, there occurs a reduction of the minimum energy E_min required of an ion with a given Z to escape the dense plasma region. (author)