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Plasma Focus (PF) devices as well as other similar pulsed discharge devices requires a variety of diagnostics for their proper control and optimization, including the voltage between electrodes, the time derivative of the discharge current, detection of X-rays and neutron emissions, and pulsed laser images (Shadow, Schlieren, interferograms). This article discusses the problem of the time reference of all these outputs and proposes specific techniques for synchronizing them based on sound physical grounds. The foundations of synchronization criterion are verified in several experiments on PF devices. [ABSTRACT FROM AUTHOR]

The notion that PF discharge circuits should be represented by an equivalent circuit having two loops instead of the traditional single one is presented. This implies that two frequencies must be expected in the currents and voltages in these devices. Also, that the current flowing into the plasma is not the same as the current flowing from the capacitor bank. Finally, the difficulties for calibrating in situ a Rogowski coil are discussed. [ABSTRACT FROM AUTHOR]

The temporal variation of the current sheet (CS) inductance in a plasma focus device can be calculated using the current derivative and the voltage signal acquired on the anode electrode, which are very common measurements in this type of device. The value of that inductance contains important information about the discharge performed including the CS lift-off from the insulator, voltage between the pinch extremes, maximum energy of the X-ray, energy delivered to the pinch and information about the actuating fusion mechanisms if the filling pressure is deuterium. This work discusses the values of the CS inductance extracted from several discharges of the Plasma Auto Confinado (PACO) plasma focus, installed in the National University of the Center of Buenos Aires-Argentina (2 kJ total energy, capacitor bank of 4 μF charged to 31 kV and a maximum current of 250 kA). [ABSTRACT FROM AUTHOR]

The dependence with the filling pressure of the hard X-ray emission of a 250 J Plasma-Focus device is presented. The study was performed on the range of Hydrogen pressures between 5 and 23 mbar. It was found that the pressure dependence of the hard X-ray intensity presents a maximum at 16.4 mbar. A threshold in the voltage drop on the pinch was observed for the X-ray emission, which agrees with the Dreicer theory for electrons runaway. [ABSTRACT FROM AUTHOR]