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Sept 19/24 PionLT/KaonLT Analysis Meeting Notes

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(Notes by GH)

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Today: PionLT 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, Nathan Heinrich, Muhammad Junaid, Alicia Postuma,

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Ali Usman, Nacer Hamdi

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CUA  Tanja Horn

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Virginia  Richard Trotta

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JLab  Dave Gaskell, Peter Bosted

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Ohio  Julie Roche

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CSULA  Konrad Aniol

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Nathan

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PionLT Lumi Analysis

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 new plotting scripts ready, working on getting COIN Lumi analysis working

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 hoping to show results next week

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Junaid

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PionLT Heep Analysis

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 Diagnosing Low SHMS 3/4Hodo Efficiencies

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 trying to understand if drop in efficiency at higher momentum is due to

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rate

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 Subdivide 3/4Eff data into momentum ranges and plot vs rate

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 Heep Runs 1186016517

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 no obvious rate dependence, drops in eff are in groups for certain settings

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 emails w/ Mark re Low 3/4Effs, he is taking a closer look

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 checking EDTM live times

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 >99% for both Heep and Physics

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 differently from KaonLT, the EDTMLT seems to be reliable for PionLT, which

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is good news

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 updated Data/MC Ratios

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 recalculating ratios using 3/4Eff instead of Report File eff for higher

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momentum, using report file 3/4Eff for P_SHMS<2.5 GeV/c

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 get ratios of 0.9951.025 before applying proton absorption correction

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 moves in the right direction, but ratios still too high

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 LH2 boiling correction

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 using Richard's correction, about 6%/100uA

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 Dave: note that Dave Mack got 2.26+/0.30%/100uA from Fall 2018 scaler

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analysis

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 *NB* should look more closely at this, it would help the ratios

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Next steps

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 implement effective charge uncertainty in yields script

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 start working on proton absorption correction

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 will attend next weekly Optics Meeting to see the status of higher P_HMS

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matrix elements

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Richard

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Diagnosing weird ratios in KaonLT High Q2 L/Tseparations

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 running tests using one of Vijay's settings, to look for differences between

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his analysis and Vijay's

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 Q2=0.38 low eps, center setting

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 shows plots of pi+n MM peak compared to version in Vijay's thesis

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 BLACK=data RED=MC

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 Vijay's data and MC are centered at correct value, reasonable agreement

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on width

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 Richard has MM peak shifted to left, by different amounts for data and MC

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 Tanja: *NB* suggest to try using Vijay's ROOT trees directly, instead of

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new hcana analysis, to diagnose what's wrong

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 will also look into CoinTime cut, since there is a shift in distro between

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Vijay and Richard

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Alicia

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BSA pi+ paper: Implementing referee suggestions

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 will use new title suggested by editor and referee

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 moved A_LU definition earlier in paper, also definitions for sig_0, sig_LT'

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 still need to calculate pi+ det efficiency and purity numbers

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 adjusted some paragraphs so systematic uncertainty discussion is in 1 para

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 chisquare analysis for theory vs expt, and discussion on model significance

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in progress

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 1st point of data extends to left of theory region, i.e. they have

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different t_min, because theory is evaluated only at central kinematics,

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and not separate (Q2,W) of each point, for this reason, it is excluded from

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the chisquare calculation

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 YCK1 has best chisquare

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 VR is 2nd best fit for our data only

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 at Q2=3.0, where CLAS data at higher t is included, VR does worse

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 could include chisquare table for different models in Supplmentary

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Material

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 BG Yu replied that he will let us say what we want about the model

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significance

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 expecting to circulate a new draft next week

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Ali

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KaonLT pi+Delta0 BSA analysis

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 working on thesis

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 redoing A_LU and sig_LT' plots, will include CLAS pi0Delta++ results (with

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sign flipped)

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 input received from PeterB re piDelta MC peak shape

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 wanted to make sure we're using the updated algorithm in SIMC

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 includes a lookup table for relativistic corrections to simple BreitWigner

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shape, which should result in improved agreement with data

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 responded that we're using the latest SIMC version

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 there is a bit of mismatch between data and MC on left side of Delta, due

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to tail coming from exclusive pi+n

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 will assess a systematic uncertainty on the tail misfit

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 will be at APSDNP meeting in early October, will circulate slides ahead of

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next week's meeting

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Nacer

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KaonLT Heep analysis

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 plot of Hodo3/4 efficiencies vs Trigger Rate

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 getting 9298% efficiencies

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 no clear correlation with rate

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 plot of Hodo3/4 efficiencies vs P_SHMS

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 planes 3,4 have particularly bad 3/4Effs

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 same curious drop at higher momentum as in PionLT

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 Dave: *NB* Log entry from Simona suggesting higher momentum protons should

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have higher efficiency in quartz bars:

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https://logbooks.jlab.org/entry/3564126

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 Ali shows plot of 3/4Eff vs SHMSRate for KaonLT Physics runs

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 Effs ~9899%

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 Heep has an efficiency problem, but physics data does not

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 *NB* PeterB makes an excellent observation:

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 apparent rate in a selected region of SHMS focal plane in Heep is much

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higher than the average rate, because not the whole focal plane illuminated

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 suggests to put cuts on HMS to select narrow band of electrons

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 Dave: this is very hard to do in the standard analyzer

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 Peter: yes, you have to do it in a special analysis

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 started working on Heep singles analysis

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 checking w/ Junaid on analysis scripts and w/ Ali on replay scripts

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Next Meeting

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 Thur Sept 26 @ 16:30 Eastern/14:30 Regina

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 KaonLT will go first

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