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Showing posts from December, 2014

Qualitative Superconductor Hysteresis Monitoring: Lab Book 2014_12_30

Lab Book 2014_12_30
Today I worked on getting a qualitative susceptometer up and running.  By qualitative I mean that we won't be attempting to analyze the returned data to accurately determine any characteristics of the superconducting materials that are to be studied, only the state of the materials, and the existence, or not of a hysteresis curve for the material.
The why of it all I’m experimenting with a quick and dirty susceptometer that can be used with the hray experiment to determine when we’ve quenched the superconductor.  Today’s work is using a ferromagnetic core, not a superconductor.  The responses are similar and I don’t have to worry about cooling a superconductor.
Experimental Setup Something old and something new I’m pressing a General Radio 1311-A audio oscillator and a Tektronix TDS 210 into service together.

The general radio signal generator is being used to drive the coil surrounding the iron core.  The oscilloscope is measuring both the signal from the General Rad…

Experimental History of Physics and Seaborg's Plutonium Sample

If you thought the history of physics was all about researching old papers and didn't involve lab work, a team at UC Berkeley begs to differ.  They recently published a paper describing their use of  passive radiation detection to identify what appears to be the first sample of plutonium large enough to be weighed.   The sample was made by Glenn Seaborg and his collaborators using large cyclotrons to bombard uranium with neutrons to transmute it into plutonium.  You can find the article at:

http://arxiv.org/abs/1412.7590