Difference between revisions of "Sign of the beam polarization"

From PolWiki
Jump to navigationJump to search
Line 6: Line 6:
 
</pre>
 
</pre>
  
Moller solenoid field points DOWNSTREAM, so electrons in iron foil point UPSTREAM.
+
Moller solenoid field points DOWNSTREAM, so magnetic moments of electron in iron foil also point DOWNSTREAM.
 +
 
 +
Magnetic moment of electron given by:
 +
<pre>
 +
\vec{mu} = (g*e)/(2*m*c) \vec{s}
 +
<\pre>
 +
 
 +
Electron has negative charge, so spin is in opposite direction of magnetic moment. So spin of polarized electrons in Moller target point UPSTREAM.  
  
 
* 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 09:51, 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}
<\pre>

Electron has negative charge, so spin is in opposite direction of magnetic moment. So spin of polarized electrons in Moller target point UPSTREAM. 

* Beni Zihlman's note on the sign of the helicity from the Moller: (ps, pdf)