Lasers developed in the Institute of Atmospheric Optics of the SB RAS (a review)

The results of research on the development of the first electric discharge lasers on active media N2, CO2, Cu, CuBr and excimer molecules at the Institute of Atmospheric Optics named after V. E. Zueva SB RAS are given. It created one of the world's first Cu-lasers with a pulse production of copper vapors due to the explosion of conductors and a transverse excitation discharge. For a copper laser, record specific generation parameters were obtained almost equal to the limit: radiation energy 2.4 J/l, peak power 120 MW/l with an efficiency of 0.16 %. For the CuBr laser operating in frequency mode, for the first time, an average radiation power of more than 100 W was obtained. In the dual pulse excitation mode, conditions were found that limit the growth of the efficiency of the CuBr laser. For him, a record efficiency of 2.7 % was obtained. For the first time, a nitrogen laser was developed with a maximum efficiency of 0.27 % with an energy of 0.8 mJ, a peak power of 160 kW. For the first time, a miniature XeCl laser with a longitudinal excitation discharge was developed, which worked both with and without buffer gases He, Ne and Ar.

Competitive Failure of Loosening and Fatigue of Bolts under Composite Excitation

At present, research on the loosening of bolts under transverse excitation and their fatigue under axial excitation has been relatively mature, but research on the competitive relationship and failure characteristics between loosening and fatigue of bolts under transverse and axial composite excitation is still insufficient. Therefore, a method to accurately determine the failure types of bolts is proposed in this study by conducting a competitive failure test of loosening and fatigue under composite excitation. According to this method, the failure types of bolts can be distinguished. The analysis results reveal that there is an obvious competitive failure relationship between the loosening and fatigue of bolts, and the failure mode is mainly affected by the ratio of the transverse and axial loads (ξ). There is a critical ξ of bolt-loosening or fatigue failure, and the critical ξ is an inherent property of the bolt and is unrelated to the load. The critical ξ of 8.8 grade M8 × 1.25 × 70 high-strength bolts under composite excitation is obtained as 0.075 mm/kN. The failure mode of bolts under composite excitation can be predicted based on the critical ξ.

Study of Production of (Anti-)deuteron Observed in Au+Au Collisions at s NN = 14.5 , 62.4, and 200 GeV

Transverse momentum distributions of deuterons and antideuterons in Au + Au collisions at s NN = 14.5 , 62.4, and 200 GeV with different centrality are studied in the framework of the multisource thermal model. Transverse momentum spectra are conformably and approximately described by the Tsallis distribution. The dependence of parameters (average transverse momenta, effective temperature, and entropy index) on event centrality is obtained. It is found that the parameters T increase and q decrease with increase of the average number of particles involved in collisions, which reveals the transverse excitation degree increases with collision centrality.

Development of Differential Equations and their Solution Using the Simulink Matlab Program, which Calculate the Self-Swinging of Synchronous Machines with Traditional and Longitudinal-Transverse Excitation

The article presents the differential equations of a synchronous generator in phase coordinates and in the coordinate system (d, q). In addition, differential equations of synchronous machines with longitudinal-transverse excitation and a block diagram based on these equations are given. The system of differential equations is solved by the operator method. On the basis of a system of differential equations using the Simulink Matlab program, a structural diagram was created and a graph of the self-swinging processes taking place in synchronous machines with conventional and longitudinal-transverse excitation was obtained. On the basis of the obtained graph, the processes of self-swinging of synchronous generators with traditional and longitudinal and transverse excitation are compared.