Difference between revisions of "Sign of the beam polarization"
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Electron has negative charge, so spin is in opposite direction of magnetic moment. Spin of polarized electrons in Moller target point UPSTREAM. | Electron has negative charge, so spin is in opposite direction of magnetic moment. Spin of polarized electrons in Moller target point UPSTREAM. | ||
| + | |||
| + | Experimental Moller asymmetry: | ||
| + | <pre> | ||
| + | [h+ - h-]/[h+ - h-] | ||
| + | </pre> | ||
* Beni Zihlman's note on the sign of the helicity from the Moller: ([https://hallcweb.jlab.org/polwiki/images/0/0d/Helicity.ps ps], [https://hallcweb.jlab.org/polwiki/images/8/8f/Helicity.pdf pdf]) | * Beni Zihlman's note on the sign of the helicity from the Moller: ([https://hallcweb.jlab.org/polwiki/images/0/0d/Helicity.ps ps], [https://hallcweb.jlab.org/polwiki/images/8/8f/Helicity.pdf pdf]) | ||
Revision as of 09:54, 1 December 2011
- Notes on the sign of the beam polarization as determined by the Moller.
Asymmetry at 90 degrees in the Center of Mass:
[N(parallel) - N(anti-parallel)]/[N(parallel) + N(anti-parallel)] = -7/9
Moller solenoid field points DOWNSTREAM, so magnetic moments of electron in iron foil also point DOWNSTREAM.
Magnetic moment of electron given by:
\vec{mu} = (g*e)/(2*m*c) \vec{s}
Electron has negative charge, so spin is in opposite direction of magnetic moment. Spin of polarized electrons in Moller target point UPSTREAM.
Experimental Moller asymmetry:
[h+ - h-]/[h+ - h-]
