[Sane-analysis] Minutes of July 14, 2010 Meeting

[O. A. Rondon]

Hi SANE team,

Below is a look backwards.

Narbe Kalantarians wrote:
> 
> _*James:*_ Looking at beam polarization. Took Dave Gaskell's subroutines
> and translated them into PERL. Producing tables for beam polarization as
> function of run#. Some run-ranges look constant, but a good part appear
> to have some dependence over time. This could partly be form not having
> the Wien angle set optimally for HallC and having some polarization
> bleed to the other Hall(s). Will correct for 1/2-wave plate and show
> results to Dave Gaskell.

I have inserted James' updated off-line beam and target polarization
values in the calculation of SANE's FOM hours. Four things stand out:

1. The average off-line Pb is from 1% to 3.4% (relative) higher than the
on-line numbers we have been using, for all periods except 5.9 GeV 80
deg, for which it is 1.8% lower.

2. The average off-line target polarization is also larger, especially
for 5.9 GeV 80 deg and 4.7 GeV para.

3. A couple of good runs not listed in the online Runlist were added.

As a result, the total FOM hours have increased by 18, dominated by
the 5.9 GeV 80 deg increase of 10 h. Since the online live time numbers
I was using have been superseded, redoing the FOM with off-line values
is pending the full replay of all runs with the latest analyzer.

A new table is posted on the wiki under "Analysis", "Updated run
summary", for use in future talks, reports, etc.
https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Main_Page#Analysis

4. the very low value P_beam = 36.3% corresponds to runs 72390 to 72411
which aren't production runs of any kind, so it does not impact our results.

In summary, considering that the off-line live times also seem to be
better than online ones, it looks like we collected at least as much
data as we have been claiming.

Cheers,

Oscar