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Aug 7/24 PionLT/KaonLT Analysis Meeting Notes

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(Notes by GH)

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Today: KaonLT will be discussed first

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Please remember to post your slides at:

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https://redmine.jlab.org/projects/kltexp/wiki/Kaon_LT_Meetings

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Present

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Regina  Garth Huber, Alicia Postuma, Ali Usman, Muhammad Junaid,

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Vijay Kumar, Nacer Hamdi, Zach Sullivan

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Virginia  Richard Trotta

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CUA  Tanja Horn

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FIU  Pete Markowitz

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Richard

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KaonLT functional fits for LTseparation

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 using 1/(W^2mp^2)^n where n=2

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 applied above Wscaling to Q2=2.1,3,5.5 data and overlaid L,T,LT,TT data for

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these three Q2 vs t

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 very interestingly, the initial preliminary separated cross sections lie

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nearly on universal curves, with very little Q2dependence at fixed t

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 this can be used to investigate what might be a good set of functional

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forms for th L,T,LT,TT fitting

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 one note of caution is that these separated cross sections are UNITERATED,

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MC/Data ratios are around ~0.5

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 also made plots of Q2dep at fixed t:

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t=0.18,0.24,0.32,0.48 for deltat<0.05

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 Richard then fit functions to these distributions

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 sigL monotonically falling with t, fit looks pretty good

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 sigT shows a bizarre "diffractive dip" at t~0.25, fit is not good

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 some discussion on what to do with this, perhaps best to ignore the

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diffractive dip structure and try to fit the remaining data and find some

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function that is adequate

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 sigTT shows a fairly flat tdependence, amplitude small

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 fit diverges at low t, need to find a function that goes to zero at

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t_min

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 sigLT is negative, as t increases it first increases in magnitude and then

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slowly gets closer to zero

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 the functional form used for TT would actually work reasonably well here

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*NB* with the addition of an offset, so that it goes to zero at t_min

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Alicia

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 BSA PRL submitted, received confirmation that it has now been sent to

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reviewers

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 this means the editor has found the PRL rationale to be sufficiently good

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to move to referee stage, which is good news

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 no other report, catching up on other tasks

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Ali

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 no update, working on thesis

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Vijay

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Low Q2 PionLT LTseparations

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 changing LT,TT functional forms, with goal of reducing phidependence of

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MC/Data ratios

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 SigLT = p1*exp(p2*t)+p3/t

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 SigTT = p1*exp(p2*t)+p3/t

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 initial results look very encouraging, high epsilon ratios look fairly flat

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for tbins 14

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 tbin 57 ratios still have some oscilations, Vijay has some ideas on how

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to improve

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 initial results do not have any iterations

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Nacer

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KaonLT Heep reanalysis

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 implement Richard's LH2 boiling correction, simple cuts, efficiencies

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 Ratios (in comparison to Bosted parameterization):

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3.8: 1.016 +/0.005 (same uncertainty for all)

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4.9: 1.041

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6.2: 1.067

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8.2: 1.112

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10.6: 1.042

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 need to understand in particular what's going on at 8.2 GeV

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 plots with Data and MC overlaid

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 3.8 agreement looks very good

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 8.2: there is an extra "feature" in HMS yptar, SHMS yptar, SHMS delta

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 MC agrees well with data on left side of yptar distribution

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 Data has a small extra peak on right side not predicted by MC, what is

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this?

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 10.6: the yptar agreement between data and MC is much better, the extra

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"feature" seems to be absent, this might be why the 10.6 ratio is much

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closer to one

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 Discussion items:

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 Richard: *NB* try plotting delta vs yptar and look for a correlation

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 Ali: could it be due to HMS matrix elements?

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 HMS should not be in saturation region for this setting

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 the missing feature at 10.6 would dissuade against this explanation

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 Tanja: *NB* can check if Data and MC are using the same matrix elements

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 Garth: *NB* maybe the "feature" is an extra source of bkd in 8.2 data

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 could investigate to see if there is any cutdependence to this

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"feature"

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 Richard: doesn't think this "feature" was present in his Heep data (same

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runs)

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 https://redmine.jlab.org/attachments/download/2257/Final_8p2_offset.pdf

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 *NB* a detailed comparison of Nacer and Richard's plots is needed

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 *NB* one 8.2 run (7974) has EDTMLT of 89%, seems low, needs investigation

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Junaid

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PionLT Heep analysis

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 working closely with Nacer to use same methods, corrected the ratio error

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calculation mistake

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 results look less encouraging that Nacer's KaonLT

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5.9: 1.054 +/ 0.005

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 yptar also has the same "extra feature"

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6.4: same here too

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 some discrepancies also in xptar, yptar distributions between data and MC

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 GH: *NB* please check SIMC input file parameters that correct target

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length, etc are used

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9.177: R=1.258 +/ 0.014

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 Pete: *NB* is there something in your applied efficiencies which could

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an overnormalization of the data?

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 Junaid pulls up a spreadsheet of corrections to data, and we notice

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SHMS_Hodo_3/4 Eff is ~89%, *NB* needs investigation

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MM Distributions broader in 2022 than 2021 data

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 plots of RasterY vs EMISS shows a big correlation

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 *NB* clearly the raster needs to be recalibrated

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 some raster calibration info is posted at

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https://redmine.jlab.org/projects/kltexp/wiki/Hall_C_Raster_Information

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Zach

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PionLT Lumi analysis

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 got plotting scripts working after ALMA9 upgrade

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 replaying data now, just started, nothing to show yet

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Next Meeting

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 Thur Aug 15 @ 15:00 Eastern/13:00 Regina

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 Dave will take notes

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 PionLT will go first

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