Difference between revisions of "Observables"
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6.) Switch from pol to unpol frequently <br> | 6.) Switch from pol to unpol frequently <br> | ||
| − | For unpolarized electron beam:<br> | + | For unpolarized electron beam the helicity dependent cross sections are: <br> |
[[Image:2.png|180px]] | [[Image:2.png|180px]] | ||
[[Image:3.png|150px]] | [[Image:3.png|150px]] | ||
| + | Where in the deuteron rest frame the spin is quantized in the direction of the virtual photon<br> | ||
| − | + | This means there is a direct relationship to first component analyzing power<br> | |
[[Image:0.png|230px]] | [[Image:0.png|230px]] | ||
Revision as of 11:03, 25 April 2013
A couple of words about Axx and how to measure it:
Axx is an asymmetry so take advantage of numerator denominator systematics cancellation:
1.) Measure Np and Nu with same cup same exact material
2.) Use same B-field
3.) Use NMR on both to measure polarization and un-polarization
4.) Let beam heating an off larmor microwave control un-polarization
5.) Keep both cold (~1K)
6.) Switch from pol to unpol frequently
For unpolarized electron beam the helicity dependent cross sections are:
Where in the deuteron rest frame the spin is quantized in the direction of the virtual photon
This means there is a direct relationship to first component analyzing power
which is very much accessible with e+D->e+N+X
In addition we have a direct relationship to b1 for low x but be weary uncertainties
