[G14_run] [EXTERNAL] g14 meeting report on G extraction for pi- p photoproduction on the neutron

Annalisa D'Angelo annalisa.dangelo at roma2.infn.it
Mon Jul 3 04:39:39 EDT 2023


Dear Haiyun,

thank you for your hard work. The final version of the analysis note is 
very good shape and shows the accuracy of your analysis.

While a detailed study of systematic errors related to the event yields 
and to beam and target polarizations has been performed, the accuracy of 
the extraction of the G asymmetry values still needs some assessment, as 
shown from the variation of results obtained for the bins that you have 
re-fitted.

G is the main outcome of this work and we should be 100% sure of the 
final results.

The main problem lays in the fact that many plots of figures from 38 to 
42 show an overall offset and an additional underlying cos 2phi 
structure. This points to the fact that the de-coupling of Sigma and G 
obtained from equations 3 and 4 is not 100% effective.

The new figures 43, 44 and 45, show that the p0 parameter, which we 
understand corresponds to the extracted G value, changes in sign and 
strength (up to a factor 10 from 0.01 to 0.1), but fortunately the 
variation is compatible with the high statistical error associated to 
the p0 parameter error.

This topic has been discussed among Mike, Tsuneo and myself during lat 
g14 meeting. As a result we would suggest to:

- perform a systematic study of the variation of the p0 parameter 
fitting ALL the distributions of figures from 38 to 42 using both i) the 
G sin 2phi function ii) the G sin2phi + a cos 2phi +c

function as you did for the figures 43, 44 and 45;

- use the results obtained for G for the two procedures to assess the 
systematic error due to the residual coupling of Sigma and G 
contributions, and add them to the systematic error table for G.


There are some other minor observation I would like to mention in the 
following:

- you name the appendixes just A, B, C. I would suggest naming a quoting 
them as Appendix A, Appendix B etc.

- you have interchanged the symbol for the double polarization asymmetry 
between g, G and |G (Capital G with an additional internal vertical line 
in the symbol).

In particular g is used when the observable is extracted from the fit, 
while G is often used as a simplified version of G and "|G". I would 
suggest using G everywhere, including in the title.

- figure 28 at page 26 is still missing figure labels

- figure 29 a at page 27 has wrong figure label.

- coefficients a,c in the captions of figures 43,44 and 45 are fit 
parameters, not constants.

- the captions of figures 43, 44 and 45 show more theta angles than 
those appearing in the plots. We would suggest to replace those figures, 
and the ones from 38 to 42, with the ones comparing the two fits 
mentioned above, including all energies and angles;

- at page 29 the sentence:

"The fitting quality is qualitatively denoted by "Prob" in the figures"

Should be substituted by something like:

  "The fitting quality is expressed by the probability ("Prob") of 
obtaining a higher value for the reduced Chi-2 variable, as shown in the 
figures upper boxes"

Should you agree on performing the fits, the text and the result should 
be updated accordingly.


Thank you for your patience and attention

All the best

Annalisa



Il 20/06/23 05:10, Haiyun Lu ha scritto:
> I finished studying the fit behavior of some G fits. Basically, 
> additional cos(2phi) and constant terms are added to represent leaked 
> Sigma. The appendix B, fitting Sigma and G, is updated with additional 
> fits. A paragraph is added in conclusion to explain this, and final 
> values are updated accordingly.
> It should be complete now.
>
> On Sun, Jun 4, 2023 at 8:45 PM Haiyun Lu <haiyun.lu at gmail.com> wrote:
>
>     I finished integrating all the comments into the note at overleaf.
>     It is ready for a final-round review before submitting to
>     CLAS review.
>     There are some touches needed for figures and I will update them
>     while it is reviewed.
>
>     Thanks,
>     Haiyun
>
>     On Fri, Apr 21, 2023 at 9:33 AM Igor Strakovsky <igor at gwu.edu> wrote:
>
>         Hi Andy,
>
>         Actually, MAID web does not report what data they are using.
>         Anyway, I am sending Victor
>         all the data which SAID has (including updates). So, please be
>         sure that MAID results is up
>         to date
>
>         Cheers, Igor
>
>         -----
>         Igor Strakovsky, SAID INS The George Washington University
>         VSTC: 571-553-8344, Cell: 703-728-5627, Skype: igors1945_2
>         Emails: igor at gwu.edu, igor at jlab.org
>
>
>         On Thu, Apr 20, 2023 at 1:09 PM Andy Sandorfi
>         <sandorfi at jlab.org> wrote:
>
>             Hi Igor,
>
>             Can you check if Victor is able to make a statement such
>             as, “the MAID PWA includes all available data up to year
>             XXXX” ?
>
>             Andy
>
>             *From: *Igor Strakovsky <igor at gwu.edu>
>             *Date: *Thursday, April 20, 2023 at 12:56 PM
>             *To: *Andy Sandorfi <sandorfi at jlab.org>
>             *Cc: *Annalisa D'Angelo <annalisa.dangelo at roma2.infn.it>,
>             g14 run <g14_run at jlab.org>, haiyun.lu at gmail.com
>             <haiyun.lu at gmail.com>, Tsuneo Kageya <kageya at jlab.org>
>             *Subject: *[EXTERNAL] Re: [G14_run] MAID
>
>             Hi Andy,
>
>             The situation with MAID is not really simple.  There is
>             one retired person, Victor, whois still active.  Ostrick
>             and Denig told me that they do not have interest/resources
>             in supporting MAID.  But Victor gave MAID predictions upon
>             my request.  My hope is that he will be a co-author of the
>             coming g14 paper
>
>             Cheers, Igor
>
>
>             -----
>
>             Igor Strakovsky, SAID INS The George Washington University
>
>             VSTC: 571-553-8344, Cell: 703-728-5627, Skype: igors1945_2
>
>             Emails: igor at gwu.edu <mailto:igor at gwu.edu>, igor at jlab.org
>             <mailto:igor at jlab.org>
>
>             On Thu, Apr 20, 2023 at 12:10 PM Andy Sandorfi via G14_run
>             <g14_run at jlab.org> wrote:
>
>                 Hi Annalisa,
>
>                 Please verify with Igor, but I believe that MAID has
>                 not been updated in years. It’s OK to show the MAID
>                 predictions with the g14 data in a paper, but one
>                 should include a statement about when that PWA was
>                 last updated.
>
>                 Andy
>
>                 *From: *G14_run <g14_run-bounces at jlab.org> on behalf
>                 of Annalisa D'Angelo via G14_run <g14_run at jlab.org>
>                 *Date: *Thursday, April 20, 2023 at 8:57 AM
>                 *To: *g14 run <g14_run at jlab.org>, haiyun.lu at gmail.com
>                 <haiyun.lu at gmail.com>, Tsuneo Kageya <kageya at jlab.org>
>                 *Subject: *[G14_run] Fwd: [EXTERNAL] MAID
>
>                 Dear All,
>
>                 I am forwarding to you the prediction from MAID,
>                 kindly provided buy Igor,  for the Sigma and G
>                 observables in pi-p photoproduction.
>
>                 All the best
>
>                 Annalisa
>
>
>
>                 -------- Messaggio Inoltrato --------
>
>                 *Oggetto: *
>
>                 	
>
>                 Re: [EXTERNAL] MAID
>
>                 *Data: *
>
>                 	
>
>                 Fri, 14 Apr 2023 09:09:02 -0400
>
>                 *Mittente: *
>
>                 	
>
>                 Igor Strakovsky <igor at gwu.edu> <mailto:igor at gwu.edu>
>
>                 *Rispondi-a: *
>
>                 	
>
>                 igor at gwu.edu
>
>                 *A: *
>
>                 	
>
>                 Annalisa D'Angelo <annalisa at jlab.org>
>                 <mailto:annalisa at jlab.org>, Franz Klein
>                 <fklein at jlab.org> <mailto:fklein at jlab.org>, Annalisa
>                 D'Angelo <annalisa.dangelo at roma2.infn.it>
>                 <mailto:annalisa.dangelo at roma2.infn.it>
>
>                 Dear Annalisa,
>
>                 Thanks
>
>                 You too, Have a nice weekend,
>
>                 Igor
>
>                 ps: Please find attached MAID predictions for Sigma
>                 and G for gn-->pi-p
>
>
>                 -----
>
>                 Igor Strakovsky, SAID INS The George Washington University
>
>                 VSTC: 571-553-8344, Cell: 703-728-5627, Skype:
>                 igors1945_2
>
>                 Emails: igor at gwu.edu <mailto:igor at gwu.edu>,
>                 igor at jlab.org <mailto:igor at jlab.org>
>
>                 On Fri, Apr 14, 2023 at 9:04 AM Annalisa D'Angelo
>                 <annalisa at jlab.org> wrote:
>
>                     Dear Igor,
>
>                     thank you! See you on Monday. Have a nice week-end.
>
>                     Annalisa
>
>                     Il 14/04/23 15:01, Igor Strakovsky ha scritto:
>
>                         Dear Annalisa,
>
>                         Monday, 10am works for me
>
>                         We can use Zoom:
>                         https://urldefense.proofpoint.com/v2/url?u=https-3A__jlab-2Dorg.zoomgov.com_j_1619984443&d=DwIDaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=5LSWsFN5KweowPCsdwCuT6TNyYmHKJ3RcKK8qa-oO-g&m=x_bvKQ8JZwxM7czMKG4JssY0fJzeSr-hRzkN3I0HE3v21MpASoSFMAioBeJrBdY9&s=T7ENbquBEay_iONTRSPsm3kez5PGxZyTqNCOVx_RBso&e= 
>                         <https://urldefense.proofpoint.com/v2/url?u=https-3A__jlab-2Dorg.zoomgov.com_j_1615438135-3Fpwd-3Dbm8xdmY0dytXeUtWV1ZEN2NVdVppdz09&d=DwMFaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=QDJbiECzfxNvPOYgSWghomOgImTBYIv1HgeGmNQ96o8&m=yAkhnpgy_6dw2nLM9lufdlr3UgnIGNdNV_T94FyAVb-lZakk5NgNMx5ooxvwMiAp&s=GCGcJed3poThbLq2pM9SXPInBAiRh2yKP3-U0AIY2e4&e=>
>
>                         Or any alternative
>
>                         Cheers, Igor
>
>
>                         -----
>
>                         Igor Strakovsky, SAID INS The George
>                         Washington University
>
>                         VSTC: 571-553-8344, Cell: 703-728-5627, Skype:
>                         igors1945_2
>
>                         Emails: igor at gwu.edu <mailto:igor at gwu.edu>,
>                         igor at jlab.org <mailto:igor at jlab.org>
>
>                         On Fri, Apr 14, 2023 at 8:52 AM Annalisa
>                         D'Angelo <annalisa at jlab.org> wrote:
>
>                             Dear Igor,
>
>                             what about Monday april 17 at 10:00 am
>                             Jlab time?
>
>                             Annalisa
>
>                             Il 13/04/23 16:36, Igor Strakovsky ha scritto:
>
>                                 Hi Annalisa,
>
>                                 Can we talk about ReggeMAID someday
>                                 by Zoom or Skype?
>
>                                 Thanks, Igor
>
>
>                                 -----
>
>                                 Igor Strakovsky, SAID INS The George
>                                 Washington University
>
>                                 VSTC: 571-553-8344, Cell:
>                                 703-728-5627, Skype: igors1945_2
>
>                                 Emails: igor at gwu.edu
>                                 <mailto:igor at gwu.edu>, igor at jlab.org
>                                 <mailto:igor at jlab.org>
>
>                             -- 
>
>                             ================================================
>
>                             Prof. Annalisa D'Angelo
>
>                             Dip. Fisica, Universita' di Roma "Tor Vergata"
>
>                             Istituto Nazionale di Fisica Nucleare
>
>                             Sezione di Roma Tor Vergata, Rome Italy
>
>                             email:annalisa.dangelo at roma2.infn.it  
>
>                             Jefferson Laboratory, Newport News, VA USA
>
>                             Email:annalisa at jlab.org
>
>                             Tel: + 39 06 72594562
>
>                     -- 
>
>                     ================================================
>
>                     Prof. Annalisa D'Angelo
>
>                     Dip. Fisica, Universita' di Roma "Tor Vergata"
>
>                     Istituto Nazionale di Fisica Nucleare
>
>                     Sezione di Roma Tor Vergata, Rome Italy
>
>                     email:annalisa.dangelo at roma2.infn.it  
>
>                     Jefferson Laboratory, Newport News, VA USA
>
>                     Email:annalisa at jlab.org
>
>                     Tel: + 39 06 72594562
>
>                 _______________________________________________
>                 G14_run mailing list
>                 G14_run at jlab.org
>                 https://mailman.jlab.org/mailman/listinfo/g14_run
>
-- 
================================================
Prof. Annalisa D'Angelo
Dip. Fisica, Universita' di Roma "Tor Vergata"
Istituto Nazionale di Fisica Nucleare
Sezione di Roma Tor Vergata, Rome Italy
email:annalisa.dangelo at roma2.infn.it  
Jefferson Laboratory, Newport News, VA USA
Email:annalisa at jlab.org
Tel: + 39 06 72594562
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/g14_run/attachments/20230703/024cf707/attachment-0001.html>


More information about the G14_run mailing list