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A new control system for capacitive energy storage with a rated energy content as high as 16 MJ is described. Capacitive energy storage has been used since 1987 to supply power for the pulsed magnetic system of the GOL-3 multiple-mirror trap. It has an operating voltage of 6 kV and consists of 6000 IK-6-150 capacitors that are located in six remote rooms together with the necessary infrastructure. The system for control and data acquisition was built using Arduino microcontroller boards operating as a distributed network of remote servers. The client part of the control system uses a personal computer with a standard configuration; communication with remote servers is effected by the TCP/IP protocol. The control system was put into regular operation at devices of the GOL-3 facility in the early 2016.

A simple Michelson CO2 interferometer for measuring the high-temperature plasma density within one interference fringe (n e l = 1016 cm−2) at two points (0.8 and 9.0 m) of the long (L = 12 m) GOL-3 corrugated trap was used. A piezoelectric element that provides displacements of the mirror in the reference arm of the interferometer is used to calibrate the interferometer and perform remote control of the initial measurement phase. The interferometer is manufactured from dielectric materials, thus excluding a mechanical action of stray magnetic fields on its elements. The time resolution of the interferometer is determined by a HgCdTe diode and equals ∼1 ns. The sensitivity of the interferometer is ∼5 × 10−4 of a fringe (n e l = 2 × 1013 cm−2).

Experiments involving irradiation of carbon targets with a hot electron plasma stream performed on the GOL-3 facility were aimed at the simulation of the effect of hot plasma of a thermonuclear reactor on plasma collectors in regimes close to those expected in the ITER. In these experiments, the emphasis was on the study of the surface-erosion processes exposed to the plasma stream. The graphite evaporation and chemical-erosion processes were studied with absolutely calibrated spectroscopic systems of the visible region. Spectroscopic experiments yielded data on the flow of carbon atoms from the surface of a plasma collector and on the contribution of chemical erosion to the surface-damage process. The obtained values are compared with the results of direct measurements of the erosion depth and the results of numerical calculations.

Experiments on the formation of a high-pressure pulse in a solid under the action of a high-power (up to 3 TW/m2) pulsed (8 μs) flow of 0.8-MeV relativistic electrons and hot plasma have been performed. A technique for measuring a high pulsed pressure from the shift of the R1 (694.23-nm) and R2 (692.8-nm) ruby fluorescence lines has been developed. The minimum pressure that can be measured by the developed instrument is 0.1 kbar. The pressure measured in experiments on the interaction of an electron beam and hot plasma with a surface reached 1.1 kbar, which is in good agreement with the calculation results. It is revealed that the X rays induced by the electron beam are quite intense enough to excite ruby fluorescence, which allows measurements to be performed without pumping the R1 and R2 lines by external radiation.

Using the upgrading of the measuring system of the GOL-3 plasma facility as an example, the structure of hardware and software environment developed for data-acquisition systems of large pulse electrophysical plants is considered. The equipment is built into 3U-size 19-inch subracks. The control computers are connected to the measuring equipment via standard network facilities (Ethernet-10/100 interface and TCP/IP protocol). At present, we have begun making basic diagnostic measurements using the ADC1250/32 multichannel synchronous data-acquisition systems.

A VUV spectrometer for the GOL-3-II plasma facility is described. It is based on the MB-3 vacuum monochromator and equipped with advanced units for spectrum recording, including a digital readout system. The spectrometer can be used either to record the spectrum over an exposure of 1 μs or more and measure the time variations in the radiation intensity at a given wavelength. The operating wavelength range is 50–400 nm.