Aug 7/24 PionLT/KaonLT Analysis Meeting Notes --------------------------------------------- (Notes by GH) Today: KaonLT will be discussed first Please remember to post your slides at: https://redmine.jlab.org/projects/kltexp/wiki/Kaon_LT_Meetings Present ------- Regina - Garth Huber, Alicia Postuma, Ali Usman, Muhammad Junaid, Vijay Kumar, Nacer Hamdi, Zach Sullivan Virginia - Richard Trotta CUA - Tanja Horn FIU - Pete Markowitz Richard ------- KaonLT functional fits for LT-separation - using 1/(W^2-mp^2)^n where n=2 - applied above W-scaling to Q2=2.1,3,5.5 data and overlaid L,T,LT,TT data for these three Q2 vs t - very interestingly, the initial preliminary separated cross sections lie nearly on universal curves, with very little Q2-dependence at fixed t - this can be used to investigate what might be a good set of functional forms for th L,T,LT,TT fitting - one note of caution is that these separated cross sections are UN-ITERATED, MC/Data ratios are around ~0.5 - also made plots of Q2-dep at fixed t: -t=0.18,0.24,0.32,0.48 for delta-t<0.05 - Richard then fit functions to these distributions - sigL monotonically falling with -t, fit looks pretty good - sigT shows a bizarre "diffractive dip" at -t~0.25, fit is not good - some discussion on what to do with this, perhaps best to ignore the diffractive dip structure and try to fit the remaining data and find some function that is adequate - sigTT shows a fairly flat t-dependence, amplitude small - fit diverges at low -t, need to find a function that goes to zero at -t_min - sigLT is negative, as -t increases it first increases in magnitude and then slowly gets closer to zero - the functional form used for TT would actually work reasonably well here *NB* with the addition of an offset, so that it goes to zero at -t_min Alicia ------ - BSA PRL submitted, received confirmation that it has now been sent to reviewers - this means the editor has found the PRL rationale to be sufficiently good to move to referee stage, which is good news - no other report, catching up on other tasks Ali --- - no update, working on thesis Vijay ----- Low Q2 PionLT LT-separations - changing LT,TT functional forms, with goal of reducing phi-dependence of MC/Data ratios - SigLT = p1*exp(p2*t)+p3/t - SigTT = p1*exp(p2*t)+p3/t - initial results look very encouraging, high epsilon ratios look fairly flat for t-bins 1-4 - t-bin 5-7 ratios still have some oscilations, Vijay has some ideas on how to improve - initial results do not have any iterations Nacer ----- KaonLT Heep re-analysis - implement Richard's LH2 boiling correction, simple cuts, efficiencies - Ratios (in comparison to Bosted parameterization): 3.8: 1.016 +/-0.005 (same uncertainty for all) 4.9: 1.041 6.2: 1.067 8.2: 1.112 10.6: 1.042 - need to understand in particular what's going on at 8.2 GeV - plots with Data and MC overlaid - 3.8 agreement looks very good - 8.2: there is an extra "feature" in HMS yptar, SHMS yptar, SHMS delta - MC agrees well with data on left side of yptar distribution - Data has a small extra peak on right side not predicted by MC, what is this? - 10.6: the yptar agreement between data and MC is much better, the extra "feature" seems to be absent, this might be why the 10.6 ratio is much closer to one - Discussion items: - Richard: *NB* try plotting delta vs yptar and look for a correlation - Ali: could it be due to HMS matrix elements? - HMS should not be in saturation region for this setting - the missing feature at 10.6 would dissuade against this explanation - Tanja: *NB* can check if Data and MC are using the same matrix elements - Garth: *NB* maybe the "feature" is an extra source of bkd in 8.2 data - could investigate to see if there is any cut-dependence to this "feature" - Richard: doesn't think this "feature" was present in his Heep data (same runs) - https://redmine.jlab.org/attachments/download/2257/Final_8p2_offset.pdf - *NB* a detailed comparison of Nacer and Richard's plots is needed - *NB* one 8.2 run (7974) has EDTM-LT of 89%, seems low, needs investigation Junaid ------ PionLT Heep analysis - working closely with Nacer to use same methods, corrected the ratio error calculation mistake - results look less encouraging that Nacer's KaonLT 5.9: 1.054 +/- 0.005 - yptar also has the same "extra feature" 6.4: same here too - some discrepancies also in xptar, yptar distributions between data and MC - GH: *NB* please check SIMC input file parameters that correct target length, etc are used 9.177: R=1.258 +/- 0.014 - Pete: *NB* is there something in your applied efficiencies which could an over-normalization of the data? - Junaid pulls up a spreadsheet of corrections to data, and we notice SHMS_Hodo_3/4 Eff is ~89%, *NB* needs investigation MM Distributions broader in 2022 than 2021 data - plots of RasterY vs EMISS shows a big correlation - *NB* clearly the raster needs to be recalibrated - some raster calibration info is posted at https://redmine.jlab.org/projects/kltexp/wiki/Hall_C_Raster_Information Zach ---- PionLT Lumi analysis - got plotting scripts working after ALMA9 upgrade - replaying data now, just started, nothing to show yet Next Meeting ------------- - Thur Aug 15 @ 15:00 Eastern/13:00 Regina - Dave will take notes - PionLT will go first