Time resolved X-ray photography of a dense plasma focus

The temporal development of the hot plasma in a dense plasma focus is studied by X-ray streak photography of ~2 ns resolution time. It is shown that initially a uniform X-ray emitting pinch plasma is formed which subsequently cools down until X-ray emission stops after ~50 ns. At a time of around 100 ns after initial X-ray emission coinciding with the break-up time of the pinch a second burst of X-rays is observed coming from small localized regions. The observations are compared with results obtained from time-resolved shadow and schlieren photography of a similar dense focus discharge (Peacock, Hobby, and Morgan).