[Frost] Question about target polarisation in the g9a run table

[Eugene Pasyuk]

  Hi Jo,

The first sign is the holding field direction. "+" is parallel to the 
beam "-" is anti-parallel.
The second sign is the direction of polariz(s)ation with respect to the 
holding field or "positive/negative" frequency.
For the analysis of the asymmetries the product of the two matters.
If the product is "+" than target polariz(s)ation is parallel to the 
beam. If the product is "-", then the polariz(s)ation is anti-parallel.
I think for the target polariz(s)ation in the run table makes sense to 
use magnitude that you got form NMR analysis and use the product for the 
sign.

This information came from the run list on the wiki.

-Eugene



On 10/14/10 14:29, mcandrew at jlab.org wrote:
> Hi Eugene,
>
> I seem to have got myself a little confused about the g9a run table.  I
> have been looking at the target polarisation column, where the target
> polarisation is given as +/-, -/+, -/- or +/+.
>
> Is the first symbol magnetic field direction with respect to the beam?
> And is the second symbol proton polarisation with respect to the magnetic
> field?  Or is the second symbol proton polarisation with respect to the
> direction of the beam?
>
> Also, out of general interest, where did this information in the table
> come from?
>
> I should have some news about target polarisation tomorrow.
>
> Many thanks,
> Jo.