Features of the Radial and Axial Distributions of the Toroidal Magnetic Field in the Axial Jet Ejection at the PF-3 Facility

Plasma Physics Reports - The results of experiments on the study of the features of the dynamics and internal structure of the axial plasma ejection at the PF-3 facility carried out within the...     

Formation of nanostructures in a plasma focus discharge

A new method for creating nanostructures in a plasma focus discharge is proposed. It is shown that the material of a micron-size dust target produced at the discharge axis efficiently evaporates and is then involved in the pinching process. After the pinch decays, the plasma expands with the thermal velocity and the evaporated dust material is deposited on the collectors in the form of fractal particles or nanoclusters organized into various structures. Such structures have a well-developed surface, which is important for various technological applications.     

Spectroscopic measurements of the parameters of the helium plasma jets generated in the plasma focus discharge at the PF-3 facility

The spectroscopic technique used to measure the parameters of the plasma jets generated in the plasma focus discharge and those of the plasma of the immobile gas through which these jets propagate is described. The time evolution of the intensities and shapes of spectral lines in experiments carried out with helium at the PF-3 facility was studied by means of electron-optical streak cameras. The plasma electron temperature, T ≈ 4–5 eV, was determined from the intensity ratio of two spectral lines, one of which (λ₁ = 5876 Å) belongs to neutral helium, while the other (λ₂ = 4686 Å), to hydrogen-like helium ions. The plasma density at different time instants was determined from the Stark broadening of these lines in the electric fields of different nature. The plasma density is found to vary from 4 × 10¹⁴ to 2 × 10¹⁷ cm^?3.     

Laboratory Simulation of the Structure of Jets from Young Stars

Plasma Physics Reports - We present the results of laboratory simulation of jets from young stars at the PF-3 plasma focus facility at the NRC “Kurchatov Institute.” The objective of...     

Determination of the plasma parameters in the PF-3 facility by the methods of X-ray spectroscopy

NeIX and NeX spectra emitted by the PF-3 high-current (2 MA) plasma focus facility are measured. A numerical model describing the spectral intensities of the emission of helium- and hydrogen-like neon ions from an optically thick plasma is proposed. The electron temperature T _e and electron density n _e in the plasma of the PF-3 facility are determined by comparing the calculated and measured emission spectra of neon.     

Study of a cumulative jet in a plasma focus discharge by the method of shearing interferometry

The dynamics of the cumulative jet formed in the course of plasma compression in a plasma focus discharge is investigated by the method of differential optical interferometry. The jet propagation velocity is found to be V = (2.3?C3) × 10⁷ cm/s, which coincides with the results of calculations performed in a 2D ideal MHD model. Ejection of matter from the anode in the late stage of the discharge due to the interaction of the cumulative jet and the electron beam with the anode surface is observed.     

Development and study of a portable plasma focus neutron source

The work is devoted to designing a compact pulsed neutron source on the basis of a plasma focus (PF) discharge. The main task was to study the physical processes accompanying a sub-kilojoule repetitive PF discharge. A device with a power supply energy of up to 600 J and pulse repetition rate of up to 10 Hz has been developed and put into operation. The dependence of the neutron yield as a function of the pulse repetition rate has been studied experimentally. A neutron flux of ～10⁸ neutrons/s has been obtained in the 3-s-long packet mode with a repetition rate of 10 Hz and discharge current of 80–90 kA.     

The effect of general anesthesia on memory in experimental animals

Full recovery of short-term memory (maximum time of delayed reactions) and of the structure of situational conditioned reflex and differentiation inhibition in dogs is observed in 1.5-2.5 h after tranquil-anaesthesia (diazepam-ketamine in doses of 0.3-15 mg/kg correspondingly) and dissociative anaesthesia by ketamine (15 mg/kg) in 6-8 h after neuroleptanalgesia (droperidol-fentanyl 2.5-0.05 mg/kg correspondingly), 20-24 h after narcosis by thiopental sodium (30 mg/kg) and by the end of the 3d day after neuroleptanaesthesia (droperidol-ketamine 2.5-15 mg/kg correspondingly). The recovery of the reaction of memory trace reproduction (of conditioned reaction of passive avoidance in rats) after various types of general anaesthesia is observed mainly in the same sequence, but on the average a day later than the short-term memory in dogs.