A method to infer the current density distribution in the current sheath of a plasma focus discharge from a magnetic probe is formulated and then applied to experimental data obtained in a 1.1 kJ device. Distortions on the magnetic probe signal caused by current redistribution and by a time-dependent total discharge current are considered simultaneously, leading to an integral equation for the current density. Two distinct, easy to implement, numerical procedures are given to solve such equation. Experimental results show the coexistence of at least two maxima in the current density structure of a nitrogen sheath.

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See supplementary material at http://dx.doi.org/10.1063/1.3480556 for a MATLAB script that evaluates the current density from measured magnetic probe and Rogowski signals and for an example that uses experimental signals.

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