[g13] g13b data quality: run by run diagnostics

[Daria Sokhan]

Dear everyone,

As part of good-run diagnostics I had promised to produce a beam
asymmetry from the  gamma + d -> p + pi- + (p)  reaction for every run
in g13b. I have now done that in two ways -- dividing each polarised
run by the nearest carbon (AMO) data, and also by combining
neighbouring PARA and PERP data. The results from both methods, along
with details, can be found on the g13 Wiki:

http://clasweb.jlab.org/rungroups/g13/wiki/index.php/Raw_asymmetries_by_run_and_polarisation_plane_--_DIAGNOSTICS

In brief, it looks like there is enough statistics to use this for
data-quality diagnostics for the lower coherent edge positions (up to
about 1.9 GeV), but above that the distributions look progressively
messier as the coherent edge rises higher. I haven't been able to get
round this yet, but there are some thoughts on the matter on the Wiki.
At the moment I produced the raw asymmetries without trip cuts,
without assigning the real polarisation and without cutting around the
coherent peak. I am just adding those stages and will send an update
when that's done.

Cheers,
Daria