[G8b_run] analysis notes

Volker Crede crede at fsu.edu
Thu Feb 2 09:45:53 EST 2012 

Hi all,

to avoid confusion, I have just replaced the file at:

     http://hadron.physics.fsu.edu/~crede/FILES/CHanrettyThesis.pdf  (about 100 MB)

with the original thesis that Chuck submitted to FSU in the Spring semester of last year. The modified sections about the experimental procedure and the updated results are available as draft analysis note at:

     http://hadron.physics.fsu.edu/~crede/FILES/CHanrettyThesis_AnalysisNote.pdf  (about 9 MB)

A few comments:

1) We have used the 2.1 GeV setting and assigned a 10% systematic error to the polarization while we have used 4% for all other settings. The 2.1 GeV data contain good physics and I am reluctant to skip this dataset.

2) Since standard SAID, MAID, and other solutions are not easily available for the two-pion channel, we have not yet superimposed any curves, yet. The beam asymmetries are first-time measurements and it is important for us to finalize the experimental results to discuss them with theorists.

Best wishes

         Volker


On Feb 2, 2012, at 5:33 AM, Ken Livingston wrote:

> Hi All,
> There are some minutes from yesteday's call at
> https://clasweb.jlab.org/rungroups/g8/wiki/index.php/Feb_01,_2012
> 
> I'll discuss the possibilities for combined reviews / analyses  with 
> Dave Ireland as soon as possible.
> 
> In the meantime, we should look at Volkers' draft analysis note and have 
> comments ready. Its at:
> http://hadron.physics.fsu.edu/~crede/FILES/CHanrettyThesis.pdf
> 
> I suggest that we add comments to this wiki page before the next meeting.
> https://clasweb.jlab.org/rungroups/g8/wiki/index.php/Polarization_observables_in_two_pion_production
> 
> Regards,
> Ken
> 
> 
> 
> On 01/27/2012 10:21 PM, Michael Dugger wrote:
>> Volker,
>> 
>> Yes.
>> 
>> Using your criteria, I think that 4% would be a good estimate for the
>> systematic uncertainty associated with the consistency of the
>> polarization.
>> 
>> Take care,
>> Michael
>> 
>> On Fri, 27 Jan 2012, Volker Crede wrote:
>> 
>>> Dear Michael,
>>> 
>>> Thanks for the update. I have already implemented your new numbers and submitted a few jobs on our cluster.
>>> 
>>> Neglecting the 2.1 GeV dataset and comparing the numbers in your table (Slide 3), would you agree that the data can still be made self-consistent to within 4%? This is the largest number I see in your table (for the 1.7 (auto) - 1.9 overlap region, PARA). My feeling is that your new results are even somewhat better than the previous ones. Can we conclude that 4% is a good estimate for the systematic error associated with the degree of polarization provided that:
>>> 
>>> 1) The latest polarization tables have been used.
>>> 
>>> 2) The polarization corrections (based on the overlap studies) have been applied.
>>> 
>>> 3) The event-based energy cut has been applied:  event edge - 200 MeV<  E(gamma)<  event edge.
>>> 
>>> Best wishes and thanks again
>>> 
>>>      Volker
>>> 
>>> PS: I am sending this from my gmail account, so it may not go to the g8b run group. FSU has a huge email problem at the moment and JLab regularly rejects emails from @fsu.edu.
>>> 
>>> 
>>> On Jan 27, 2012, at 2:24 PM, Michael Dugger wrote:
>>> 
>>>> Hi,
>>>> 
>>>> I have made some slight changes to the polarization modification. Volker
>>>> and Ken helped me determine that there was an inconsistency in how I was
>>>> determining which polarization look-up table to use for each event. The
>>>> inconsistency led to the coherent edge being wrong by up to 4 MeV (~ half
>>>> an eCounter).
>>>> 
>>>> The results are very similar to what I had shown previously. A pdf showing
>>>> a comparison of the new results to the old ones can be found at
>>>> http://www.jlab.org/Hall-B/secure/g8b/ASU/polCorrectionV3.pdf
>>>> where the new results are in blue.
>>>> 
>>>> Note: There is one difference in results worth mentioning. I no longer see
>>>> the need to remove eCounters>  299 (within the overlap region) for the 1.9
>>>> GeV data set :)
>>>> 
>>>> To implement the new modification, one only needs to replace the ldPar
>>>> values with the those given at the bottom of this email (also listed on
>>>> the pdf).
>>>> 
>>>> I apologize for any inconvenience this may cause.
>>>> 
>>>> Sincerely,
>>>> Michael
>>>> 
>>>> New ldPar values:
>>>> 
>>>> 1.3 manual
>>>> ldPar(1) = 1.007560
>>>> ldPar(2) =-0.5872520E-02
>>>> ldPar(4) = 1.012520
>>>> ldPar(5) =-0.6416970E-02
>>>> 
>>>> 1.5 manual
>>>> ldPar(1) = 1.012790
>>>> ldPar(2) =-0.4507690E-02
>>>> ldPar(4) = 1.002800
>>>> ldPar(5) =-0.1880110E-02
>>>> 
>>>> 1.7 manual
>>>> ldPar(1) = 0.9893110
>>>> ldPar(2) =-0.1880110E-02
>>>> ldPar(4) = 0.9893210
>>>> ldPar(5) =-0.2127790E-02
>>>> 
>>>> 1.7 auto
>>>> ldPar(1) = 0.9962880
>>>> ldPar(2) =-0.1159220E-02
>>>> ldPar(4) = 1.030480
>>>> ldPar(5) =-0.1110110E-01
>>>> 
>>>> 1.9 auto
>>>> ldPar(1) = 1.012930
>>>> ldPar(2) =-0.2772200E-02
>>>> ldPar(4) = 0.9998200
>>>> ldPar(5) =-0.1616160E-02
>>>> 
>>>> 2.1 manual
>>>> ldPar(1) = 0.9968230
>>>> ldPar(2) =-0.2214870E-01
>>>> ldPar(4) = 1.007930
>>>> ldPar(5) =-0.7647950E-02
>>>> 
>>>> 
>>>> _______________________________________________
>>>> G8b_run mailing list
>>>> G8b_run at jlab.org
>>>> https://mailman.jlab.org/mailman/listinfo/g8b_run
>>>> 
>>> 
>>> 
> 
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