Study of x-ray spectrum from the plasma focus with subnanosecond time resolution

The build-up of an adequate model for the mechanism of charged particle acceleration is one of the urgent problems in the plasma focus studies. It is known that near-electrode processes play an important role in the case of a solid anode. The goal of a given study was to investigate the dynamics of the electron beam and the spectrum of the hard X-ray (HXR) produced in the current sheath run away regime within the plane geometry of electrodes. For studying the HXR-spectrum a four channel circuit of measurements was used. Each channel is a combination of a fast plastic scintillator (t < 0.5 ns) with a photoelectron converter (t < 0.3 ns). The radiation under study is introduced into the detector shielded against the electromagnetic noise and against the scattered radiation through various filters. The detectors were placed symmetrically, at the same distances from the anode. The control over the discharge symmetry and over the homogeneity of a radiation field in each discharge was realized with the thermoluminescent dosemeters and with a pin-hole camera. The X-ray spectra at each instant of time was reconstructed from the experimental absorption curves by the modified regularization technique