Features of Radial Distributions of Poloidal Magnetic Field in Axial Jet Ejection in a Plasma Focus

The radial distribution of the B_z field at a distance of 35 cm from the generation region of the axial jet emission (the anode surface of the setup) has been studied using the PF-3 plasma-focus facility. The measurements have been performed using multichannel magnetic probes located in the flight chamber of the facility. This has made it possible to measure the magnetic field distribution at 18 points on both sides of the flight chamber axis. The magnetic probes have been calibrated both in absolute value and in the magnetic field direction. An external multi-turn solenoid has been used to create the initial longitudinal (poloidal) magnetic field. The solenoid power supply circuit has allowed obtaining different B_z field directions: along or against the facility axis. It is shown that the poloidal field distribution reaches its maximum in the bunch center and decreases at the periphery, regardless of the presence of an external magnetic field. The B_z field has a radial distribution B_z(r), close in shape to the magnetic field distribution of the solenoid. The work is performed within the program for the simulation of jets of young stellar objects.