[Halld-physics] GlueX Note: Orientations of the Photon Beam Polarization for Spring 2017

[Alexander Austregesilo]

Dear Colleagues,

I submitted a draft of my note 'Orientations of the Photon Beam 
Polarization for Spring 2017 from rho(770) Decay Asymmetries' to DocDB:

https://halldweb.jlab.org/doc-private/DocDB/ShowDocument?docid=3977

Abstract:
We use the production of the rho(770) meson to extract the deviation of 
the nominal polarization plane of the photon beam, providing an estimate 
of the statistical and systematic uncertainties. The results should be 
used consistently by all studies, especially for final states with a 
limited data set which does not permit to extract these offsets.

In addition to the results, it includes a short introduction of the 
method, that shows that the extracted offset psi_0 is exactly equivalent 
to the offset phi_0 that appears in pseudoscalar beam asymmetries.

Please let me know if you have any corrections and suggestions.

Have a nice weekend,

Alex