Gone in 60 nanoseconds
A Z-pinch x-ray source at maximum plasma density taken with a 3 nanosecond nitrogen laser-pumped dye laser using a lateral shearing interferometer. hmmmm... Think of it as something like a mirage, light bent by hot air, except that here the hot air is a current of electrons in a thin gas. Wait a second!.... This isn't a photograph!.... Boot this!... but this is probably closer to classic photography than most of the images on this site. This one was taken with a real 4x5 view camera using Polaroid Type 55 Positive/Negative film. True... my flash is a bit obscure... but you could build one in your basement. (see Jim Small, an old friend, in an equally old Scientific American Amateur Scientist article). Doc Edgerton, one of my all-time heroes and one of the pioneers of high-speed photography, once came to my MIT lab to talk to me about using these lasers himself. At the time he was taking shadow pictures of live, swimming water fleas...... OK... you can toss it if you have to, but it IS beautiful. The Z-pinch starts as a thin sheet of current something like the surface of a donut or a bagel (a torus) sliced in half for breakfast. The current forms a strong magnetic field inside the bagel which acts like a pressure. The bagel expands and the hole in the bagel shrinks. When the bagel hole collapses on itself the plasma gets very dense and very hot... That's the column you see in this shot. It is so hot that it generates x-rays, which was the point of the device. X-rays for making very dense electronic circuits. I never really understood the process until this image came out of the film tray that day. I held up the negative and could immediately see what was happening. That is the beauty of doing science. Sometimes I see a bagel... sometimes when I'm feeling more upscale I see a wine glass. In a few nanoseconds this plasma column blew out, but I can't put that photo sequence into the JPG show... it would be a montage... not a straight photograph...... Tell you what.... I'll just stick the montage in my photo file for fun. Watch the bagel hole shrink. Watch the plasma column blow out afterwards. See the beauty of it all.
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