“…Observations of bright-spots in a number of different Z-pinch configurations ͑vacuum sparks, 4,6,12 post-stagnation gas-puff Z-pinches, 5,13 plasma foci, 7,14 and fiber Z-pinches 1-3,9,11 ͒ have given rise to a wide range of explanations for formation processes ͑energy deposition from electron beams, 4,5 radiative collapse, 6,7,15 and the mϭ0 instability 1,9 ͒.…”