Tuesday, August 26, 2014

More magnet work and a bit of attenuation: Lab Book 2014_08_26

Summary:  It was a somewhat uneventful day.  Current carrying cables to connect the power supply and the iron yoke magnet were constructed.  A detector longer run was made with the Cd 109 source, but the peak resolution did not improve.

If you're new to the experiment, scroll to the bottom for background.


Six gauge quarter inch copper crimp lugs were attached to the ends of two lengths of cable.  These cables will transmit current from the power supply to the magnet.


To Do:
Add terminal lugs for power cord.  Wire chassis to ground.



Detector Work
A longer counting run was made using the Cd 109 source.  The results will be entered in tomorrow’s lab book.  There was not a significant improvement in peak resolution.
Bias
1500 V
Gate Window
0.5 uS
Threshold
1.5mV
Attenuation
0 dB
Data set
HBC_00021
Source
Cd 109 in Dewar
Start Time
5:22 AM
Stop Time
3:46 PM
Date
2014_08_20 – 2014_08_21
x-y scope V/div
1, 0.5
Shielded?
Yes
Tube
Harshaw B-

Background
Hirsch's theory of hole superconductivity proposes a new BCS-compatible model of Cooper pair formation when superconducting materials phase transition from their normal to their superconducting state[1].  One of the experimentally verifiable predictions of his theory is that when a superconductor rapidly transitions, (quenches), back to its normal state, it will emit x-rays, (colloquially referred to here as H-rays because it's Hirsch's theory).

A superconductor can be rapidly transitioned back to its normal state by placing it in a strong magnetic field.  My experiment will look for H-rays emitted by both a Pb and a YBCO superconductor when it is quenched by a strong magnetic field.
This series of articles chronicles both the experimental lab work and the theory work that’s going into completing the experiment.

The lab book entries in this series detail the preparation and execution of this experiment… mostly.  I also have a few theory projects involving special relativity and quantum field theory.  Occasionally, they appear in these pages.

Call for Input
If you have any ideas, questions, or comments, they're very welcome!

References
1.  Hirsch, J. E., “Pair production and ionizing radiation from superconductors”, http://arxiv.org/abs/cond-mat/0508529



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