Kaon_LT Experiment

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h1. *KaonLT/PionLT Weekly Meetings*

KaonLT/PionLT collaboration analysis meetings. Please add your talk to the meeting ahead of time. Add the newest meeting to the top of the list!

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h2. 2026 Meetings

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h3. April 16-17, 2026

* Garth's notes attachment:mtg_26apr16-17.txt

* Alicia 

** Comparing background-subtracted data with omega MC (no scaling): ratios on order of 10-30

** This is using physics_omega.f, not any form of physics_iterate.f

** Now looking into LTsep code from both Bill and Junaid 

** In parallel verifying data efficiencies etc

** attachment:omega_ratios_defaultSIMC.pdf

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h3. April 9-10, 2026

* Garth's notes attachment:mtg_26apr09-10.txt

* Richard

** All high Q2 KaonLT settings are finished and saved in /cache/hallc/kaonlt/Pass4a_Apr_2026

*** This version of replays is with hphi_offset=0 and using the "2018 Matrix":https://github.com/JeffersonLab/hallc_replay_lt/blob/master/DATFILES/hms_recon_coeff_opt2018.dat

*** Full replays are in Pass4a_Apr_2026/ROOTfiles/Analysis/KaonLT

*** Cut root files are in Pass4a_Apr_2026/Skim_ROOTfiles/Analysis/KaonLT

*** The NPS version of matrix and offsets will be ran as Pass4b in the near future

** The full replays and cut root files were sent to batch using the new swif2 scripts developed

*** A first pass template version can be found at the "trottar/farm_template":https://github.com/trottar/farm_template repo

*** Note: this repo needs to be updated with the latest scripts

* Vijay

** Updated cross sections after the toffsets and 5 iterations. attachment:Vijay_Apr10_26.pdf

** Yield ratios, attachment:aver.pl_375_781.pdf, attachment:aver.pl_375_629.pdf, attachment:aver.pl_375_286.pdf 

* Kin

** attachment:kaonlt-09April-2026.pdf

** improved hgcer hole cut.

** Optimized LT iteration code by preprocessing SIMC events so reweighting function is vectorized.

** Systematic uncertainty from MM range : need to extend from 1.14 to ~ 1.16.

* Sameer

** attachment:Sameer_Jain_PID_cuts_Q1.6_lowE_v1.pdf

** Initial Pid cuts for Q21p60_lowE 

* Alicia 

** More shape study plots: attachment:Q3p0W3p14center_lowe_yields.pdf

** Submitting new replay with coin blocking 

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h3. April 2, 2026

* Garth's Notes attachment:mtg_26apr02.txt

* Kin

** attachment:kaonlt-4.2.pdf

** hgcer hole cut not enough in highe settings

** sigmaL and sigma T trend "reversed" after t-shift in Q3p0W3p14, to be investigated

* Alicia

** attachment:uChan_apr2.pdf 

** Progress on binned shape study

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h3. March 26-27, 2026

* Garth's Notes attachment:mtg_26mar26-27.txt

* Richard

** attachment:KaonLTMeeting3_26-3_27_2026.pdf

** The theta_cm->0 spikes were due to improper empirical fit background subtraction for non-MM variables. A new procedure which uses an event-by-event MM-weighted background subtraction for each variable.

** The Q2=3.0, W=2.32 has dramatically improved after these fixes.

* Nacer

** attachment:20260327_kaonLT_nacer.pdf

** Applied t-shift according to missing mass shift

** the longitudinal and transverse cross sections changed drastically. Planning to shift the lowest edge of t-bin to avoid the unphysical region (t<t_min)

** From Sameer, the code block needed for adding coin time Blocking factor and its errors to the report replay output: attachment:CoinTime_blocking_snippet.txt

* Kathleen

** Finalised PID cuts and applied both random and dummy subtractions to data.

** Extracted a preliminary yield with charge normalisation.

** attachment:LD2+_Yield.pdf

* Kin

** acceptance, diamond systematics in SIMC. 

** no sensitivity from kaon-decay in SIMC. 

** attachment:kaonlt-3.27-simc-systematics.pdf

** attachment:kaon-decay-sys.pdf

* Sameer

** Initial PID cuts for Q21p60W3p08 Target LH2

** attachment:Sameer_PionLT_PID.pdf

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h3. March 19-20, 2026

* Garth's Notes attachment:mtg_26mar19-20.txt

* Alicia

** Modified u-phi binning

** Extending shape study to each individual bin

** attachment:uChan_mar19.pdf

* Kathleen

** Added acceptance cuts and looked into the detector cuts further.

** attachment:LD2+_AcceptanceCuts.pdf

* Nacer

** studied t-shift effect on cross sections and yields.

** attachment:20260320_kaonLT_nacer.pdf

* Richard

** attachment:KaonLTMeeting3_19-3_20_2026.pdf

** Discovered a spike in theta_cm as it approaches zero (especially evident at low t). This is likely a resolution issue that leaks theta_cm into an unphysical region. 

** attachment:

** Draft 1 of write-up on statistical uncertainty calculations

* Sameer

** Coinblock corrections with fixed and variable cuts on the ROC variable.

** attachment:sameer_26-march-2026.pdf

* Kin

** yield systematics from turning radiative on and off in SIMC is huge

** Dave : Use pion systematics

** attachment:kaonlt-3.19.pdf

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h3. March 12-13, 2026

* Garth's Notes attachment:mtg_26mar12-13.txt

* Nacer

** First look at sigT(Sigma/Lambda) using two approaches.

** Investigated the first two t-bins in sigL, no issue seen in pion subtraction up to now.

** attachment:20260312_kaonLT_nacer.pdf

* Kathleen

** attachment:LD2+_DetectorCuts.pdf

* Nermin

** attachment:NGC_Calib.pdf

* Alicia

** Working on u-phi binning for omega

** attachment:uChan_mar12.pdf

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h3. March 05-06, 2026

* Garth's Notes attachment:mtg_26mar5-6.txt

* Kin

** attachment:kaonlt-3.6.pdf

** found unphysical events in data in center settings. Solution is to apply Garth's calculation of t-shift originated from MM-shift.

* Junaid

** Rebinned t. Divided the t-distribution into 7 bins.

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_7tbinning.pdf

** Calculated Unsep and Sep L/T/LT/TT cross-sections.

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_LT_Sep_xsection_7tbin.pdf

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_Rosenbluth_Sep_xsection_7tbin.pdf

* Nacer

** Swapped the cross section model with pole term in sigT to sigL, the results look very similar, with a very small improvement with sigT containing the pole term.

** verified the separated cross sections difference with and without the missing mass shift, leading to RMSE of ~ 4%. It seems to better keep the mass shift, with the corresponding t-shift.

** explore the difference in the Raw Coin time distributions between Winter18 and Autumn18 parameter files.

** attachment:20260305_kaonLT_nacer.pdf

* Garth

** t-shift codes attachment:tshift_kaonff.f attachment:tshift_piff.f attachment:linux_suppl.inc

* Nermin

** attachment:NGCerCalibrationforLD2-5march26.pdf

* Kathleen

** attachment:LD2+_timingCuts.pdf

** Initial timing and PID cuts for LD2+.

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h3. February 26-27, 2026

* Garth's Notes attachment:mtg_26feb26-27.txt

* Junaid

** Rebinned t. Divided the first two t-bins into 3 (total 6tbins).

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_tbinning.pdf

** Calculated Unsep and Sep L/T/LT/TT cross-sections.

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_LT_Sep_xsection.pdf

** attachment:Q3p85_W2p62_t0p21_Prod_Analysis_Rosenbluth_Sep_xsection.pdf

* Gabriel

** Q-fit method of extracting Lambda, Sigma0 yields

** slides: https://redmine.jlab.org/issues/1221

** original paper: attachment:0809.2548v3.pdf

* Nermin

** attachment:NGCer_Calibration_LD2.pdf

* Kin

** attachment:kaonlt-2.26.pdf

** first study of SIMC yield systematic uncertainty (Q2=3.0,W=3.14)

* Richard

** attachment:KaonLTMeeting2_26-2_27_2026.pdf

** Issues in yield comparisons were successfully fixed through a combination of cut mismatching, SIMC differences, and some miscommunication (e.g., what cuts files actually were using). 

** Full replays are beginning soon. First setting expected to be finished next week.

* Alicia

** Missing mass resolution calculation for phi-007 ERR

** Kinematic comparison plots: fixed previous issue (missed runs in post-replay processing)

** attachment:kinematics_Q3W3ch_feb26.pdf

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h3. February 19-20, 2026

* Garth's Notes: attachment:mtg_26feb19-20.txt

* Nacer

** Found the optimal models for sig_T, sig_L, sig_LT, sig_TT that produce the best Data/SIMC ratios ~ [0.8, 1.2].

** attachment:20260219_kaonLT_nacer.pdf

* Nermin

** attachment:PionLD2-sitting26feb19.pdf

* Alicia

** Data/MC kinematic comparison plots 

** Take normalization/scaling factors from missing mass shape study and apply to other variables

** Plots show both all MC compared to data and omega MC compared to background-subtracted data 

** attachment:kinematics_Q3W3ch_feb19.pdf

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h3. February 12-13, 2026

* Richard's Notes: attachment:mtg_26feb13.txt

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h3. February 5-6, 2026

* Richard's Notes: attachment:mtg_26feb5-6.txt

* Nermin Sadoun

**  PID study for LD2-: attachment:Pion_Electroproduction_LD2minus.pdf

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h3. January 29-30, 2026

* Richard's Notes: attachment:mtg_26jan29-30.txt

* Vijay

** Performed 2-2 iterations after changing the +-10 coin cuts. The separated cross sections are similar without iterations.

** Dave said, not understanding why we need these changes (coint time ones). 

** We need to have group discussions on this.  

** attachment:Vijay_Jan30_26.pdf

* Kin

** Updated pion subtraction : omit if there is only noise at MM \approx 0.938.

** Cross section in progress : Reweight inconsistency between Richard and I in 0-th iteration.

** attachment:kaonlt-1.29.pdf

* Nermin

** Did Randoms subtraction for Missing mass for LD2+

** Updated PID cuts for LD2+

** attachment:Pion_PID_LD2_30Jan26.pdf

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h3. January 22-23, 2026

* Garth's Notes attachment:mtg_26jan22-23.txt

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h3. January 15-16, 2026

* Garth's Notes attachment:mtg_26jan15-16.txt

* Alicia

** Potential solution for Pythia issue at Q2=3, W=2.32

** attachment:uChannel_Postuma_Jan16.pdf

* Vijay

** PonLT summer 2019 systematic uncertainty studies.

** attachment:Vijay_Jan16_26.pdf

* Kin

** Diamond cut by overlapping all (data, simc) diamond fit --> mismatch in Right high e, Q^2=3.0, W=2.32

** Kaon LT separated xsect for Q^2=4.4, W=2.74, inconsistency with Richard's result. To be checked.

** attachment:kaonlt-1.15.pdf

* Richard

** attachment:KaonLTMeeting1_15-1_16 2026.pdf

** Ratios, kinematics plots, and cross-sections were shown for Q2=3.0/W=2.32, Q2=4.4/W=2.74, Q2=5.5/W=3.02 using the same parameters.

** There are still some issues discussed by Kin that need to be resolved before they are finalized.

* Nermin

** attachment:Efficiency_PionLD2-sitting16jan26.pdf

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h3. January 08-09, 2026

* Garth's Notes attachment:mtg_26jan8-9.txt

* Junaid

** Slides: attachment:Q3p85_W2p02_LTSep_PreAnalysis_08_01_2026.pdf

** Looked at Aerogel Cut for physics setting Q2 = 3.85, W = 2.02. Aerogel cut is not making any difference to MMpi.

* Kin

** Check correlation between MM and SHMS variables, etc

** matrix element files checked : low momentum for HMS

** HMS and SHMS distribution disagreement in SIMC / data after iteration. 

** Slides: attachment:kaonlt-1.8.pdf

* Nermin

** attachment:PionLD2_random_subtrations8Jan26.pdf

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h2. 2025 Meetings

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h3. December 18-19, 2025

* Garth's Notes attachment:mtg_25dec18-19.txt

* Kin

** attachment:kaonlt-12.19.pdf

** attachment:main_0000.pdf, attachment:main_0001.pdf, attachment:main_0002.pdf, attachment:main_0003.pdf

** under-subtraction in Left high e settings

** Huge mismatch in resolution between SIMC and data in Center high e

** temporary solved by fitting to norm * (smeared SIMC) + bkg

** SIMC resmult study --> increase from 3.5 to 4.5 matches width in high t bin but not lowest t bin.

** MM vs SHMS variables correlations, see main*.pdf

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h3. December 11-12, 2025

* Garth's Notes attachment:mtg_25dec11-12.txt

* Richard

** attachment:KaonLTMeeting12_11-12_12.pdf

** Lowered the event threshold for accepted t-phi bin yields to be >=1 (previously >=25). This fixed a majority of the "bad" ratio bins, resulting in a nice set of ratio plots for Q2=3.0, W=2.32. There are still some outstanding bins and errors need to be investigated before final results.

* Junaid

** attachment:Q3p85_W2p02_LTSep_PreAnalysis_11_12_2025.pdf

** Adjusted Aerogel Cut for physics setting Q2 = 3.85, W = 2.02. Calculated Aerogel efficiency > 85%.

** Adjusted Diamond cut for physics setting Q2 = 3.85, W = 2.02.

* Alicia

** attachment:Postuma-uChan-Dec12.pdf

** Updated u-channel statistics estimate

** Pythia experimentation (odd behaviour at W=2.32)

* Kin

** attachment:kaonlt-12.12.pdf

** Updated background fit by simultaneouly fit norm * SIMC + Cheb. 

** Slightly improved yield ratio in high t bin

* Gabriel

** different method to determine kinematic offsets from physics data

** attachment:GNiculescu_klt_kinematic_offsets_25dec09.pdf

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h3. December 4-5, 2025

* Garth's Notes attachment:mtg_25dec4-5.txt

* Junaid

** attachment:Q3p85_W2p02_LTSep_PreAnalysis_05_12_2025.pdf

** Checked Aerogel Cut for physics setting Q2 = 3.85, W = 2.02.

** Determined MM offsets and cut for physics setting Q2 = 3.85, W = 2.02.

** Determined Diamond cut for physics setting Q2 = 3.85, W = 2.02.

* Richard

** attachment:KaonLTMeeting12_4-12_5.pdf

** Improved t-phi bin by bin empirical fits which corrects (or removes) bad fits more consistently

** Updated the uncertainty calculation for the empirical fits to use the covariance.

* Kin

** attachment:kaonlt-12.5.pdf

** add polynormial fit to background using the side bands.

** Slight improvement on yield ratio.

* Alicia 

** Showed geometric Aerogel-RF PID cut 

** Only a few slides - added to PDF for Dec 11/12 update

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h3. November 28, 2025

* Garth's Notes attachment:mtg_25nov28.txt

* Junaid

** attachment:PionLT_KaonLT_Collab_Meeting_28_11_2025.pdf

** Used 1.2 <= RF cut <= 3.4 for physics setting Q2 = 3.85, W = 2.02, t = 0.49.

** Calculated RF cut efficiency (~ 0.998) for physics setting Q2 = 3.85, W = 2.02, t = 0.49.

** Calculated pion absorption factor (~ 0.955) for physics setting Q2 = 3.85, W = 2.02, t = 0.49.

* Nacer

** attachment:20251128_kaonLT_nacer.pdf

** Tried different models for sigT, while cancelling sigL, sigLT, sigTT

** Found an optimal model for sigT, next will be to come up with an optimal sigL.

* Alicia

** attachment:u_channel_dvcs_feasibility.pdf

** Feasibility of u-channel DVCS extraction: could get upper limit from several settings

** This is an available project, I am leaving it for now

* Kin

** attachment:kaonlt-11.28.pdf

** attachment:Q3p0_W3p14_center_high.csv

** attachment:Q3p0_W3p14_center_low.csv

** attachment:Q3p0_W3p14_left_high.csv

** attachment:Q3p0_W3p14_left_low.csv

** attachment:Q3p0_W3p14_right_high.csv

** corrected mm shift to simc peak

** counts per bin are recorded

** refining background subtraction under the the Lambda peak

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h3. November 20-21, 2025

* Garth's Notes attachment:mtg_25nov20-21.txt

* Junaid

** attachment:PionLT_KaonLT_Collab_Meeting_12_11_2025.pdf

** Calculated pion absorption factor (~ 0.965) for physics setting Q2 = 3.85, W = 2.62, t = 0.21.

** Calculated RF cut efficiency (~ 0.998) for physics setting Q2 = 3.85, W = 2.62, t = 0.21.

* Richard

** attachment:KaonLTMeeting11_20-21_25.pdf

** Analysis of the bad t-phi bins for Q2=3.0/W=2.32 was shown. 

** The old one Chebyshev fit was replaced with two (quadratic+Chebyshev) to handle bad fits per t-phi bin better.

** A breakdown of the next analysis steps was also discussed.

* Nacer

** attachment:20251121_kaonLT_nacer.pdf

** Data/SIMC ratio is improved, with sigma_T only and the rest terms cancelled sigma_L, sigma_LT, sigma_TT.

** the sigma_T model does not fit well the data.

* Kin

** attachment:kaonlt-11.21.pdf

** Fix reweighting by using average theta calculated from average Q^2, W and t instead of directly taking from `P_kin_secondary_th_xq`.

** Data/SIMC ratio is improved, especially in the first t bin, but still need refinement due to mm mismatch with SIMC and background subtraction.

* Alicia 

** attachment:u_channel_dvcs_prelim.pdf

** Paper is submitted

** Enabled missing mass squared in the latest replay

* Vijay

** attachment:Vijay_25Nov21.pdf

** systematic check of pion blocking correction

** kinematic and acceptance plots for 2 Q2=0.425 settings

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h3. November 13-14, 2025

* Garth and Richard's Notes attachment:mtg_25nov13-14.txt

* Richard

** attachment:KaonLTMeeting11_13-14_25.pdf

** Using the same functional forms as Q2=4.4, W=32.74

** Ratios look fairly flat with little structure. There are 2-3 bins that dip and need investigation

** The distributions look okay overall, but more iterations will be needed (currently only 3). The delta distributions, in particular, are a bit off.

* Vijay

** The PionLT 2019 summer data analysis now includes updated cross-section results after applying the pion coin blocking and pion absorption corrections.

** attachment:Vijay_Nov014_25.pdf

* Kin

** attachment:kaonlt-11.14.pdf

** modified binning to extend lowest and highest t bin coverage. counts reported.

** Q3p0_W3p14 : 0-th iteration results look well but updated parameters lead to negative weights. Investigation on-going.

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h3. November 6-7, 2025

* Garth's Notes attachment:mtg_25nov6-7.txt

* Junaid

** Slides: attachment:LTSep_Analysis_06_Nov_2025.pdf

** Ratios are much closer to 1, and interference oscillations are reduced.

** Comparison plots look good.

** Ratio Plots: attachment:Q3p85_W2p62_t0p21_ProdCoin_iter13_ratios.pdf

** Unsep xsect Plots: attachment:Q3p85_W2p62_t0p21_ProdCoin_iter13_unsep_xsect.pdf

** Comp Plots: attachment:Q3p85_W2p62_t0p21_ProdCoin_iter13_comp.pdf

* Richard

** attachment:KaonLTMeeting11_6_25.pdf

** After the changes to simc vertex variables, a new set of functional forms were found that work quite well for Q2=4.4, W=2.74

** There is still a bit of fluctuation in the cross sections so more iterations are needed to stabilize these. 

* Nacer

** attachment:20251107_kaonLT_nacer.pdf

** L,T,LT,TT cross section models optimization continue.

* Vijay

** The coin blocking study of the PionLT summer 19 data is completed. 

** attachment:Vijay_Nov05_25.pdf

* Kin

** attachment:kaonlt-11.7.pdf

** Yields are consitent with Richard's result on Q^2=4.4,W=2.74 settings except for the treatment of pion and other bkg subtraction.

** mm peak too small in Lowest t bin in Q^2=3.0, W=3.14 left lowe setting. Better binning in t is needed.

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h3. October 30-31, 2025

* Garth's Notes attachment:mtg_25oct30-31.txt

* Junaid

** Slides: attachment:LTSep_Analysis_30_Oct_2025.pdf

** Fixed phi (data and SIMC) conversion to 0 - 360 deg scale.

** Added 360 to the phi<0.

** Ratios are much closer to 1, and interference oscillations are reduced.

** Plots: attachment:Q3p85_W2p62_t0p21_ProdCoin_iter05.pdf

* Richard

** attachment:KaonLTMeeting10_31_25.pdf

** Fixed an issue in my user simc which gave incorrect theta/phi vertex values.

** New results show oscillation in ratios, interference terms need adjustment.

* Nacer

** attachment:20251031_kaonLT_nacer.pdf

** Corrected the phi range mismatch between vertex and reconstructed phi angle.

** The data/SIMC yields for lambda have improved and the interference bumps are reduced.

** First look at data/SIMC yields for sigma and the ratios are near 1 with some exceptions.

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h3. October 23-24, 2025

* Garth's Notes attachment:mtg_25oct23-24.txt

* Alicia

** Doing missing mass shape studies on other settings

** Found odd Pythia distribution at Q2=3, W=2.32 (lowest W in data)

** Plots: attachment:uchan-pythia-oct23.pdf

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h3. October 16-17, 2025

* Garth's Notes attachment:mtg_25oct16-17.txt

* Nacer

** Slides: attachment:20251017_kaonLT_nacer.pdf

** introduced LT and TT interferences, but the data/simc ratios became further from unity. 

* Richard

** attachment:KaonLTMeeting10_16_25.pdf

** Adding Q2 dependence to functional forms using power-law scaling.

* Vijay

** The PionLT summer 2019 coincidence time blocking correction study.

** attachment:Vijay_Oct017_25.pdf 

* Kin

** Slides: attachment:kaonlt-10.17.pdf

** Numerical issue of cross section when -t is out of experimental range, e.g. -t > 0.7. Added a cut on -t for SIMC vs data comparison.

** Comparison with Richard's yields on Q^2=4.4, W=2.74 settings. Results are consistent for lowe settings but deviate a lot in highe settings. 

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h3. October 10, 2025

* Garth's Notes attachment:mtg_25oct10.txt

* Junaid

** Slides: attachment:LTSep_Analysis_10_Oct_2025.pdf

** Iteration v23: attachment:Iteration_v23.pdf

** Added an extra |t| dependence term in sigmaLT and SigmaTT. Ratios indicate cos2phi oscillations. Sigma LT looks fine, but sigmaTT needs to be changed.

* Nacer

** Slides: attachment:20251010_kaonLT_nacer.pdf

** Compared SIMC abd Data missing mass plots, and SIMC lambda is well aligned with Data

** pion subtraction is good

* Richard

** attachment:KaonLTMeeting10_10_25.pdf

** Fit for both Q2 settings together (at W=2.22) for Fpi-2 look really good using the FiSAMi algorithm.

** Q2=4.4, W=2.74 are in a preliminary finalized state with everything looking very good with the current parameterization and functional forms. 

* Vijay

** Updated the pion and proton absorption and yield correction factors spreadsheet with their errors. 

** These corrections should be used for PionLT summer 2019 data.

** These should be final numbers as well.

** attachment:Vijay_Pion_Proton_Absorption_Corr_sheet.pdf

* Kin

** Slide: attachment:kaonlt-10.10.pdf

** added a missing mass cut on comparison of HMS and SHMS variables. Distributions shape are reasonable. 

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h3. October 3, 2025

* Garth's Notes attachment:mtg_25oct03.txt

* Junaid

** Slides: attachment:LTSep_Analysis_03_Oct_2025.pdf

** Iteration v17: attachment:Iteration_v17.pdf

** Added a exponential factor in |t| term. Ratios indicate oscillations. Sigma TT looks fine, but sigmaLT needs to be changed.

** Iteration v18: attachment:Iteration_v18.pdf

** Modified sigma LT term. Still seeing oscillations. Sigma TT looks fine, but sigmaLT needs to be changed.

* Richard

** attachment:KaonLTMeeting10_3_25.pdf

** Early stages of testing my LT fit algorithm on separated xsect data. The Fpi-2 data is the initial check, with more to follow.

* Kin

** Slides: attachment:kaonlt-10.3.pdf

** updated replay files with the recent CUTS and PARAMS files

** Lt iteration : Change to uniform binning, yield ratios are fairly flat but the cross section calculation is wrong and that the comparison with SIMC needs a cut on missing mass.

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h3. September 26, 2025

* Garth's Notes attachment:mtg_25sep26.txt

* Junaid

** Slides: attachment:LTSep_Analysis_26_Sep_2025.pdf

** Iteration v11: attachment:Iteration_v11.pdf

** Added a parameter to the denominator in the |t| term. Ratios have a bump in the middle. Sigma TT looks fine, but sigmaLT needs to be changed.

** Iteration v12: attachment:Iteration_v12.pdf

** Added a parameter in the |t|^power term. Ratios indicate oscillations. Sigma TT looks fine, but sigmaLT needs to be changed.

* Nacer

** Slides: attachment:20250926_kaonLT_nacer.pdf

** When we evaluate the functional form of sigm_L for -t value in SIMC, in particular at low -t bins, which are beyond the range of data, we obtain high values of sigm_L leading to bigger discrepency between SIMC and data yields.

** Data/SIMC ratios at low -t bins are improved by limiting the parameter in the exponential of sigm_L.

** sig_LT and sig_TT are set to zero. 

* Alicia

** attachment:uchan-update-sep26.pdf

** Updates on u-channel shape study

** Asymmetry, meson production ratios likely not a feasible measurement 

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h3. September 19, 2025

* Garth's Notes attachment:mtg_25sep19.txt

* Junaid

** Slides: attachment:LTSep_Analysis_19_Sep_2025.pdf

** Iteration v10: attachment:Iteration_v10.pdf

** Changed |t|^power terms in sigmaLT and sigmaTT. Ratios indicate oscillations. Functions need to be changed.

* Nacer

** Slides: attachment:20250919_kaonLT_nacer.pdf

** Data/SIMC are very close to 1, after correction to the separated cross section functional forms, sig_LT and sig_TT are set to zero. 

** Due to sinusoidal behavior in the yields ratio, we will need to include the interference terms in the cross section

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h3. September 12, 2025

* Garth's Notes attachment:mtg_25sep12.txt

* Junaid

** Slides: attachment:LTSep_Analysis_04_Sep_2025.pdf

** Iteration v7: attachment:Iteration_v7.pdf

** Added sigmaLT and sigmaTT terms.

* Kin

** Slides: attachment:update-2025.9.12.pdf

** replayed all 10 settings in Q2=3.0 W=3.14 and Q2=2.1, W=2.95

** small shape difference in missing mass for the proton peak from true pion and misidentified pion.

** modified diamond fit function

** modified \sigmaLT term to avoid negative CS in Left settings, to be optimized.

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h3. September 4, 2025

* Garth's Notes attachment:mtg_25sep04.txt

* Junaid

** Slides: attachment:LTSep_Analysis_Sep_4_2025.pdf

** Added W_factor to functional forms. 

** Set sigma_LT and sigma_TT terms to zero. Getting ratios close to 1.

* Kin

** Slides: attachment:missing-mass-fit-9.4.2025.pdf

** Gaussian fit to Lambda peak, consistent result for all runs in Q^2=3.0, W=3.14

** Subtract background from Sigma peak by modeling it with a "crystalball function":https://www.jlab.org/primex/weekly_meetings/slides_2009_07_17/dmitry/crystalball.html

---

h3. August 28, 2025

* Garth's Notes attachment:mtg_25aug28.txt

* Junaid

** Slides: attachment:LTSep_Analysis_Aug_28_2025.pdf

** Getting ratios around 35. 

** Looking into scripts to figure out the issue.

---

h3. August 21, 2025

* Garth's Notes attachment:mtg_25aug21.txt

* Junaid

** Slides: attachment:LTSep_Analysis_Aug_21_2025.pdf

** Changed sigma_L functional form from Tanja's to Peter's version.

---

h3. August 14, 2025

* Garth's Notes attachment:mtg_25aug14.txt

* Nathan

** Away at doctor's appointment, but there is spirit.

** working on write up for RefTimes study, as well as Lumi study

** Slides with details: attachment:CoinLumiUpdate20250814.pdf

* Nacer

** Due to challenging fit of the separated cross sections, we cancelled the interference terms for now, LT and TT.

** The fits seems converging, but the data/SIMC ratios after couple of iterations although fairly flat, are far from unit.

** Slides: attachment:20250814_kaonLT_nacer.pdf

* Alicia

** Modifying figures for PLB resubmission

** attachment:asym_paper_edits_aug14.pdf

---

h3. August 7, 2025

* Tanja's Notes attachment:mtg_25aug07.txt

* Richard

** attachment:KaonLTMeeting8_7_25.pdf

** Tried out a few empirical background fits which improved the results quite a bit. There are few, if any bad bins, with ratios looking pretty flat. Going forward, a 2nd order Chebyshev will be used. With and without pion subtraction was also tested with small differences, but pion subtraction will remain to get a better empirical fit.

* Nacer

** Test the new SIMC weight calculation script during the iterations, by a small variations, +/-5% and +/-10%,  in the separated cross section fits.

** The results are consistent, and small variation in the parameters lead to small variations in the Data/SIMC ratio.

** attachment:20250807_kaonLT_nacer.pdf

* Alicia

** Working on implementing referee comments from PLB

** Looking for perspectives from the group: attachment:asym_paper_edits_aug7.pdf

---

h3. July 31, 2025

* Garth's Notes attachment:mtg_25jul31.txt

* Junaid

** Was using the wrong variables to calculate SIMC weights. Fixed weight calculation script.

** Working on iterations using Tanja's functional forms.

** attachment:PionLTMeeting_LTSep5.pdf

* Richard

** attachment:KaonLTMeeting7_31_25.pdf

** Expanded the MM range to clearly show the proton leak through (especially at left/right settings at both epsilons). The HGCer leak through is not as problematic as initially assumed, which is good. Focus will be on fitting this background.

* Nacer

** attachment:20250731_kaonLT_nacer.pdf

** First look at the first iteration and functional forms fit optimization.

* Alicia

** attachment:simc-pythia-july31.pdf

** Pythia+SIMC events compared to data. Good reproduction of background

---

h3. July 24, 2025

* Garth's Notes attachment:mtg_25jul24.txt

* Alicia

** attachment:pythia-simc-jul24.pdf

** Successfully ran Pythia events through SIMC, albeit at very low efficiency

* Ivan

** Updated statistical errors on ALU for non-neglible subtractions

** Alicia's derivation: attachment:asym-err-derivation.pdf (Ivan derived the same on paper, posting digital version)

* Junaid

** Ran 01st iteration. Ratios are so high.

** Found an error in the weight calculation script.

** attachment:Q3p85_W2p62_t0p21_iter01.pdf

---

h3. July 17, 2025

* Garth's Notes attachment:mtg_25jul17.txt

* Richard

** attachment:KaonLTMeeting7_17_25.pdf

** Using the same functional forms and parameterization as last week showed very nice results when all phi settings were included for Q2=4.4, W=2.74

** There is still some refinement to the functional forms, but overall things are almost ready for this setting.

* Alicia

** Analysis update: progress on both Xphasespace and Pythia approaches to background modelling

** attachment:uchannel_updates_july17.pdf

** Theory update: summary of discussions with Bill at JLab regarding the interpretation of u-channel results

** attachment:uchannel_notes_july17.pdf

* Ivan

** Setting up for systematic studies on K+ BSA

** attachment:KaonLT_Zhenchuk_July17.pdf

* Junaid

** Ran 00th iteration to calculate new params.

** Working on weight calculation script.

** attachment:PionLTMeeting_LTSep4.pdf

---

h3. July 10, 2025

* Garth's Notes attachment:mtg_25jul10.txt

* Richard

** attachment:KaonLTMeeting7_10_25.pdf

** The pion subtraction procedure has been refined, leading to a noticeable improvement in the cross-section ratios at Q² = 4.4 GeV² and W = 2.74 GeV (center setting only).

** Tighter MM_K cuts were applied, yielding a modest additional improvement in the ratios.

** Some bins still exhibit contamination. However, incorporating all kinematic settings should mitigate this to some extent. If residual sigma contamination persists, a dedicated sigma fit may be necessary once all settings are fully examined.

* Junaid

** ran 00th iteration to extract new params.

** Working on weight calculation script.

** attachment:PionLTMeeting_LTSep3.pdf

---

h3. July 3, 2025

* Garth's Notes attachment:mtg_25jul03.txt

* Richard

** attachment:KaonLTMeeting7_3_25.pdf

** The functional forms last week work fairly well for all Q2 settings (minus 2.115 which needs to be rerun as the cut root files were removed from volatile).

** The pion subtraction has significant improvement on fits and will be the focus over the next week. 

* Junaid

** Started LTSep analysis with Tanja's functional forms

** attachment:PionLTMeeting_LTSep2.pdf

---

h3. June 26, 2025

* Garth's Notes attachment:mtg_25jun26.txt

* Richard

** attachment:KaonLTMeeting6_26_25.pdf

** attachment:OldFits_6_25_2025.pdf

** attachment:Cauchy_Schwarz_LT_Proof_v2.pdf

** Resolved a minor bug in the pion subtraction uncertainty calculation and refined the pion scaling factor to enhance subtraction accuracy. Additionally, a new formulation for the unseparated cross section was implemented, based on the Cauchy-Schwarz inequality and constrained by L,T>0.

** Using the updates described above, new models were constructed for Q2=4.4 and W=2.74. Comparisons between data and SIMC show good agreement, with stable ratios and solid cross section fits. While further refinements are needed, this model provides a strong foundation.

* Nacer

** first look at KaonLT, Q2=0.5 GeV2, unseparated and separated cross sections.

** attachment:20250626_kaonLT_nacer.pdf

* Ivan

** Kaon BSA updates: Q2=0.5, W=2.40 and all 10.6 GeV run period data

** attachment:KBSA_Zhenchuk_June26.pdf

---

h3. June 20, 2025

* Garth's Notes attachment:mtg_25jun20.txt

* Ivan

** Kaon BSA summary of work to date

** attachment:KaonBSA_Zhenchuk_Jun20.pdf

* Junaid

** Did Rosenbluth fitting on Q2=3.85 Setting

** attachment:PionLTMeeting_LTSep1.pdf

---

h3. June 5, 2025

* Garth's Notes attachment:mtg_25jun05.txt

* Richard

** attachment:theta_changes_3p0_2p32.png

** Corrections to the calculation of θ, using the proper Λ mass, yield more reasonable values. However, the LT and TT terms require adjustment to accurately account for these changes. A more pronounced t-dependence is now evident and must be better described.

* Vijay

** Pion and proton absorption studies are completed.

** attachment:Vijay_update_June05_25.pdf

---

h3. May 29, 2025

* Garth's Notes attachment:mtg_25may29.txt

* Vijay

** Pion and Proton absorption studies are conducted.

** attachment:Vijay_update_May29_25.pdf

* Junaid

** Plotted ratios vs phi.

** attachment:PionLT_ratios_vs_phi_distribution.pdf

---

h3. May 22, 2025

* Garth's Notes attachment:mtg_25may22.txt

* Richard

** attachment:KaonLTMeeting5_22_25.pdf

** Although the Q² = 3.0, W = 3.14 ratio appears promising at first glance, the kinematic and acceptance plots clearly indicate that the older functional form provides a superior fit. Encouragingly, the three key scaling points—Q²/W = 3.0/2.32, 4.4/2.74, and 5.5/3.02—continue to use this form consistently. These will be the main focus in preparation for the upcoming Hall A/C meeting in June.

* Vijay

** working to determine the pion absorption correction factor for the data Yield correction.

** compared some of the variables with the Alicia ones to understand that things are working for me.

** found HGC and AGC peaks are not in my plots. attachment:Vijay_update_May22_25.pdf

---

h3. May 15, 2025

* Garth's Notes attachment:mtg_25may15.txt

* Richard

** attachment:KaonLTMeeting5_15_25.pdf

** Q² = 3.0 (W = 2.32) and Q² = 4.4 (W = 2.74) are currently in a relatively stable state. While some refinements remain, their overall condition is solid. 

** A detailed breakdown of all systematic uncertainties, along with estimated timelines, was also reviewed.

---

h3. May 8, 2025

* Garth's Notes attachment:mtg_25may08.txt

* Richard

** attachment:KaonLTMeeting5_8_25.pdf

** A dip in the unseparated cross section at 180° was traced to a ROOT issue: while a cut on the NTuple successfully excluded bad data in the TGraph, the TF2 fitting function ignored the cut; this was resolved by applying the cut directly in the Fortran script before loading into ROOT.

** Remaining tasks include reanalysis and re-parameterization at multiple Q2/WQ2/W settings, complete SIMC and replay runs, and finalizing a systematics study in preparation for the upcoming Hall A/C meeting.

* Nacer

** See attached plots for SIMC and data yields  comparison for each setting.

** attachment:center_lowe_kinematics_lambda.pdf

** attachment:left_lowe_kinematics_lambda.pdf

** attachment:center_highe_kinematics_lambda.pdf

** attachment:left_highe_kinematics_lambda.pdf

** attachment:right_highe_kinematics_lambda.pdf

** attachment:center_lowe_kinematics_sigma.pdf

** attachment:left_lowe_kinematics_sigma.pdf

** attachment:center_highe_kinematics_sigma.pdf

** attachment:left_highe_kinematics_sigma.pdf

** attachment:right_highe_kinematics_sigma.pdf

* Junaid

** attachment:PreLTSep_Analysis.pdf

** Calculated physics yields for each phi-bin of each t-bin. Looks good.

** Calculated simc yields for each phi-bin of each t-bin. Looks good.

** Calculated DATA/SIMC yields and made comparisons plots.

** attachment:Q3p85_W2p62_t0p21_loweps_center_Comp_Plots.pdf

** attachment:Q3p85_W2p62_t0p21_higheps_center_Comp_Plots.pdf

---

h3. May 1, 2025

* Garth's Notes attachment:mtg_25may01.txt

* Nathan

** presented the current status of the coin RF time cuts for lumi.

** got some strange shapes, plots contained here attachment:CTimeRefPlots_pass1.zip

** going to investigate further

* Richard

** attachment:KaonLTMeeting5_1_25.pdf

** The large interference terms have been attributed to zero or negative unseparated cross-section values observed at angles near 180 degrees.

* Junaid

** Calculated physics yield for "Q2=3.85, W=2.62, t=0.21"

** Need to check the errors.

** attachment:LTSep_Analysis_v4.pdf

---

h3. April 24, 2025

* Garth's Notes attachment:mtg_25apr24.txt

* Richard

** attachment:KaonLTMeeting4_24_24.pdf

** Improved ratios at Q² = 3.0 and W = 2.32, with the previously exaggerated TT now under control. Fits are largely acceptable, though interference contributions are still too large.

** For Q² = 3.0, W = 3.14, the ratios are excellent and the kinematic agreement is strong; however, the fit quality is still notably poor.

* Vijay

** Performed the missing mass offset study for the Q2 = 0.42 GeV2 data.

** Still 3 settings at high epsilon have some issues to fix.

** attachment:Vijay_update_April24_25.pdf  

* Alicia

** Replayed 10.6 GeV data for proton mass, helicity enabled

** Preliminary PID / MMp plots:

** attachment:uchannel_updates_apr24.pdf

* Junaid

** Calculated physics yield for "Q2=3.85, W=2.62, t=0.21"

** Need to check the errors.

** attachment:LTSep_Analysis_v4.pdf

* Nathan

** Looking into Coin Reference times to see if there is an effect on the rate dependence.

** Found some strange shapes in the raw coin time distributions: attachment:RefTimesPass0.zip

** checking if calling the "coin time ref cut" file in the replay script changes anything. Looks like it does: attachment:RefTimesPass1.zip

---

h3. April 17, 2025

* Garth's Notes attachment:mtg_25apr17.txt

* Richard

** attachment:KaonLTMeeting4_17_24.pdf

** Q² = 3.0, W = 2.32 analysis is progressing well. The t-dependence of the ratios is flat, with minimal structure, consistent with the same functional form used at Q² = 4.4 and 5.5. Some tuning of the W-dependence is still needed to bring the ratios closer to unity. Kinematics and acceptances between data and SIMC are closely matched. However, an unusually large LT/TT cross-section has been observed and warrants further investigation.

* Alicia

** attachment:uchannel_updates_apr17.pdf

** Preliminary look at u-channel data at Q2=3, W=3.14, high epsilon

* Junaid

** Selected t-range from 0.16 to 0.50.

** Divided t-distribution into 5 bins.

** attachment:LTSep_Analysis_v3.pdf

---

h3. April 10, 2025

* Garth's Notes attachment:mtg_25apr10.txt

* Richard

** attachment:KaonLTMeeting4_9_24.pdf

** At Q² = 3.0 and W = 2.32, the ratios appear to be converging when using the functional forms derived from Q² = 4.4 and 5.5. Additional iterations are needed to confirm this trend, but the current functional forms seem to perform well across all three Q² settings.

* Vijay

** The all polar plots for the three epsilon data at Q2 = 0.42 GeV^2.

** attachment:Vijay_April10_2025.pdf

---

h3. April 3, 2025

* Garth's Notes attachment:mtg_25apr03.txt

* Richard

** attachment:KaonLTMeeting4_3_24.pdf

** The setting Q² = 5.5, W = 3.02 aligns well with the functional form used at Q² = 4.4, W = 2.74. However, statistics are limited at this Q², and the kinematic coverage extends into higher |t| values (tₘₐₓ ≈ 0.9). To improve the statistical reliability, tₘₐₓ will be reduced, which should yield slightly improved ratios in the upper bin. This high-|t| behavior is consistent with observations at Q² = 3.0, W = 2.32 and Q² = 4.4, W = 2.74. Focus will now shift to the Q² = 3.0, W = 2.32 setting.

* Vijay

** Made the polar plot (tcos(phi) vs tsin(phi)) from the higher epsilon settings.

** Draw the circles with the exact same radii as the t bins width. 

** Last circle may be changed later. attachment:tvsphiQp425W2p2.png

* Junaid

** Checked t-ti Resolution.

** Plotted tvsphi distribution to check the full phi coverage. Selected t-range from 0.16 to 0.50.

** Divided t-distribution into 7 bins. Need to do 5 bins. 

** attachment:LTSep_Analysis_v2.pdf

---

h3. March 27, 2025

* Garth's Notes attachment:mtg_25mar27.txt

* Vijay

** Made polar plots (tcos(phi) vs t sin(phi)) from the full phi coverage of the epsilon (high epsilon).

** This epsilon has five experimental settings (Righ1, Right2, Center, Left1 and Left2).

** Make this polar plot for each setting and also combine one (adding all five settings).

** These plots have all the requred cuts.    

** attachment:Vijay_Mar27_2025.pdf

* Junaid

** attachment:LTSep_Analysis_v1.pdf

** Calculated Missing Mass offsets and cut (0.90 < MMpi <1.06) for Physics Setting - Q2=3.85, W=2.62, t=0.21 (2 epsilons)

** attachment:Q3p85_W2p62_t0p21_PionProd_MMCut.pdf

** Finalized Diamond cut.

** attachment:Q3p85_W2p62_t0p21_ProdCoin_DiamondCut.pdf

* Nacer

** attachment:20250327_kaonLT_nacer.pdf

** Looked at merged settings for high epsilon data for different -t bins for both lambda and sigma resonances, to verify the coverage in phi.

* Alicia

** attachment:shmsPA_Postuma_Mar27.pdf

** Significant progress on SHMS geant4

** Number of total stopped tracks agrees with spreadsheet, but missed 3/4 triggers does not

** A large number of secondary particles still cause a 3/4 trigger

** Simulation output updated to allow PID on tracks

* Nathan

** showed plots with interesting puzzle. After applying Dave Mack's eLT + CPULT as Gaskel had requested last time (calling this pass14).

** After doing that we lose any consistent trends with any rate that I've investigated. Plots: attachment:LumiPass14.zip

---

h3. March 20, 2025

* Garth's Notes attachment:mtg_25mar20.txt

* Richard

** attachment:KaonLTMeeting3_20_24.pdf

** A decent set of functional forms have been selected for Q2=4.4, W=2.74. Before finalizing these, these functional forms will be tested on Q2=5.5/W=2.95 then Q2=3.0/W=2.32. These three share an x=0.4 so thus vital for the scaling studies.

* Vijay

** The diamond cut determined from the low epsilon, Center setting did not work properly for SIMC.

** I studied the diamond cut for low epsilon, left1 and left2 settings and found the same problem (SIMC diamond is not happy with the data diamond).

** I studied the data offsets that need to be applied in SIMC too.

*** I tested this study for low epsilon, Center setting and the SIMC diamond slightly improved.  

** attachment:Vijay_Update_March20_25.pdf

* Nacer

** attachment:20250320_kaonLT_nacer.pdf

** t-binning width in data is compared to the width of delta t (ti-t) in simc.

** t-binning width in data is compared to -t vs. Phi to check the coverage.

* Nathan

** attachment:LumiUpdate2025-03-20.pdf

** presented the mystery of HMS rate dependence in coin lumi data.

** More plots coming later

---

h3. March 13, 2025

* Garth's Notes attachment:mtg_25mar13.txt

* Nacer

** attachment:20250313_kaonLT_nacer.pdf

** Study an optimal t-binning for lambda and sigma kaon LT data. 

* Vijay

** Studied the t binning and diamond cuts for the Q2 = 0.42 GeV2 data.

** attachment:Vijay_updates_Mar13_2025.pdf

---

h3. March 6, 2025

* Garth's Notes attachment:25mar06.txt

* Richard

** attachment:KaonLTMeeting3_6_24.pdf

** Fixed issue with lowest t-bin for sigT. There was pion contamination that was causing oversubtraction. The tmin was increased, which fixed that issue. 

* Junaid

** attachment:HeeP_Studies_Ratios.pdf

** HeePCoin ratios look good and are close to 1.

** HeeP Ratio plots - attachment:HeeP_Studies_Ratios_Plots.pdf

---

h3. February 27, 2025

* Garth's Notes attachment:mtg_25feb27.txt

* Nacer

** attachment:20250227_kaonLT_nacer.pdf

** Diamond cut (W vs Q^2) study for lambda and sigma resonances for each data setting

* Junaid

** attachment:PionLT_Meeting_Update_v3.pdf

** Finalized HeePCoin Offsets.

** Applied global offsets to BE from 5.9GeV-9.9GeV and applied separate offsets to 10.6GeV.

** Plots without offsets- attachment:HeePCoinPlots_nooffset.pdf

** Plots with calculated offsets- attachment:HeePCoinPlots_withoffset.pdf

** Plots with modified offsets- attachment:HeePCoinPlots_withoffsetP0p47.pdf

---

h3. February 20, 2025

* Garth's Notes attachment:mtg_25feb20.txt

* Richard

** attachment:KaonLTMeeting2_20_24.pdf

** Comparison of Q2=5.5 and 4.4 with a t-dependent set of functional forms (incorrect sigT causes this). There is nice consistency between the two. Updating to the best set of functional forms is the next step for a comparison across Q2=3.0(W=3.14),4.4, 5.5 for next week.

* Junaid

** attachment:PionLT_Meeting_Update_v2.pdf

** Need to calculate two sets of offsets, one for beam energies 5.9GeV-9.9GeV and other for 10.5GeV.

** Plots without offsets- attachment:HeePCoinPlots_nooffset_v1.pdf

** Plots with calculated offsets- attachment:HeePCoinPlots_withoffset_v1.pdf

---

h3. February 13, 2025

* Garth's Notes attachment:mtg_25feb13.txt

* Richard

** attachment:KaonLTMeeting2_13_24.pdf

** Adjusted W dependence for Q2=4.4, W=2.74 for better ratios.

* Junaid

** Calculated OOP offsets. Got +1.875mr for HMS and -0.155mr for SHMS

** attachment:PionLT_Meeting_Update_13_02_25.pdf

---

h3. February 6, 2025

* Garth's Notes attachment:mtg_25feb06.txt

* Richard

** attachment:KaonLTMeeting2_6_24.pdf

** Q2=4.4, W=2.74 shows very nice agreement between data and SIMC with simplified functional forms of T and TT. The ratios are stable and fairly flat but seem to settle at R~0.2. The W dependence may need to be adjusted.

* Nacer

** attachment:20250206_kaonLT_nacer.pdf

** Q2=0.5, W=2.4, Central Low epsilon data compared to SIMC for both lambda and sigma missing mass ranges.

* Alicia

** attachment:geant4slides.pdf

** Presentation on the SHMS geant4 progress. Simulation is mostly complete, attempting to verify output

* Junaid

** Updated HMS optics matrix from NPS optics group for 5.9, 6.1 and 6.7 GeV.

** Work in progress for 5.6 GeV.

** Implemented zeroth order CMOP matrix elements for 5.9, 6.1 and 6.7 GeV.

** attachment:HMS_Optics_update_v1.pdf

---

h3. January 30, 2025

* Garth's Notes attachment:mtg_25jan30.txt

---

h3. January 23, 2025

* Garth's Notes attachment:mtg_25jan23.txt

* Nacer

** First look at data and SIMC yields for kaon LT at 3.8 GeV, Q^2 = 0.5, W = 2.40, Central low E

** SIMC yields are wierdly high 

** attachment:20250123_kaonLT_nacer.pdf

* Nathan

** looking into applying Dave Mack's rate corrections in lumi data https://hallcweb.jlab.org/doc-private/ShowDocument?docid=1063

* Vijay

** Coincidence timing information updates for Q2 = 0.42 GeV2 data.

** attachment:Vijay_Jan23_2025.pdf

---

h3. January 16, 2025

* Garth's Notes attachment:mtg_25jan16.txt

* Nathan

** Showed Lumi Singles scaler yields after applying boiling correction

** attachment:CombinedPlotHMS_LH2_Scalar.pdf attachment:CombinedPlotHMS_rate_LH2_Scalar.pdf attachment:CombinedPlotLH2_Singles_Rate_Scalar.pdf attachment:CombinedPlotLH2_Singles_Scalar.pdf attachment:CombinedPlotSHMS_LH2_Scalar.pdf attachment:CombinedPlotSHMS_rate_LH2_Scalar.pdf

** tentative rate correction of 0.029+-0.002 %/MHz obtained

---

h3. January 9,2025

* Garth's Notes attachment:mtg_25jan09.txt

* Nathan

** Presented updated Lumi Singles Scaler Yields for both HMS and SHMS

** https://redmine.jlab.org/attachments/2695 https://redmine.jlab.org/attachments/2696 https://redmine.jlab.org/attachments/2697 https://redmine.jlab.org/attachments/2698 https://redmine.jlab.org/attachments/2699 https://redmine.jlab.org/attachments/2670

** found a boiling correction of (2.8 +- 0.17 (stat) +- 0.69 (sys)) %/100uA

---

h3. January 2, 2025

* Garth's Notes attachment:mtg_25jan02.txt

* Nacer

** attachment:20250102_kaonLT_nacer.pdf

---

h2. 2024 Meetings

---

h3. December 19, 2024

* Garth's Notes attachment:mtg_24dec19.txt

* Nacer

** attachment:20241219_kaonLT_nacer.pdf

* Richard

** attachment:KaonLTMeeting12_19_24.pdf

** Using center data only, nice ratios have been found. There are good chi2 for L,LT but TT, and especially, TT need improvement which is evident from ratios.

---

h3. December 12, 2024

* Richard's Meeting Notes attachment:mtg_12dec24.txt

* Richard

** attachment:KaonLTMeeting12_12_24.pdf

** t-range: Adjusted from 0.15-0.6 to 0.16-0.6.

** Binning Scheme: Changed to 5 bins in t and 10 bins in phi. Increased the number of events per bin.

*** Outcome: Significant reduction in pion leakage for the lowest t-bin.

** Upper t-range: Need to reduced from 0.6 to 0.5 to address high-background issues in the highest t-bin.

* Nacer

** attachment:20241212_kaonLT_nacer.pdf

---

h3. December 5, 2024

* Garth's Notes attachment:mtg_24dec05.txt

* Richard

** attachment:KaonLTMeeting12_5_24.pdf

** A MM shift to the lambda peak was implemented. 

** It was found that in the lowest t-bin (<0.2) there is a significant pion background. This greatly lowers the statistics in this bin. 

---

h3. November 21, 2024

* Garth's Notes attachment:mtg_24nov21.txt

* Richard

** attachment:KaonLTMeeting11_21_24.pdf

** The MM peaks for high and low epsilon show a shift by ~10 MeV. The shift is different for high and low but consistent for all Q2 except Q2=3.0, W=2.32. The beam energy will be checked first and if things look fine then an offset will be applied on a run by run basis (plus for SIMC).

* Nacer

** HeeP singles data/simc ratios deviate from 1.

** the W distribution left and right tales are not produced in SIMC, and vary for each beam energy settings.

** attachment:20241121_kaonLT_nacer.pdf

---

h3. November 14, 2024

* Garth's Notes attachment:mtg_24nov14.txt

* Nathan

** showed plots of lumi status. More work needs to be done

** attachment:CombinedPlotCarbon.pdf attachment:CombinedPlotCoin.pdf attachment:CombinedPlotHMS_LH2.pdf attachment:CombinedPlotHMS_LH2.pdf attachment:CombinedPlotLH2_ALL.pdf attachment:CombinedPlotLH2_Singles.pdf attachment:CombinedPlotSHMS_LH2.pdf

---

h3. November 7, 2024

* Dave's Notes attachment:mtg_24nov07.txt

---

h3. October 31, 2024

* Garth's Notes attachment:mtg_24oct31.txt

* Junaid

** Working on SHMS PID study for pions attachment:SHMS_PID_Studies_v3.pdf

** Did study on "EBeam=7.937, Q2=3.85, W=3.07, x=0.31, θ_SHMS=5.50 (Right)" & attachment:SHMS_PID_plots_v3.pdf