Kaon_LT Experiment

                 Jan 4/24 PionLT/KaonLT Analysis Meeting Notes

                 ---------------------------------------------

                              (Notes by GH)

                     Today: PionLT will be discussed first

Please remember to post your slides at:

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

Present

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Regina - Garth Huber, Nathan Heinrich, Ali Usman, Alicia Postuma, 

   Muhammad Junaid, Nacer Hamdi, Vijay Kumar

CUA - Richard Trotta, Casey Morean, Tanja Horn

JLab - Dave Gaskell

FIU - Pete Markowitz

Nathan

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- working on slides for Hall C meeting, need to have draft slides ready for

  Thurs Jan 11

- will start working on Lumi Carbon singles data from Sept/22

Junaid

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Completed replay of PionLT data

- 7 scripts for Heep (coin, HMS-sing, SHMS-sing), Lumi, Physics

- batch scripts take 3 arguments

- various issues encountered during the replays that took a lot of attention

  - broken symlinks, typos, duplicate run#

  - fixed all issues, all data now on cache disk

Tracking Efficiency study

- SHMS cuts to be used

  - it's important that variables involving tracked info (e.g. P.aero.xAtAero)

    are not used in any way in the study

  - add a cut CAL>0.05 (no_track variable) on SHMS

- HMS cuts

  - add H.cal.etotnorm > 0.7

Richard

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HGC cut status in physics analysis

- mis-spoke at last meeting that no HGC cut is applied

 - in reality, HGC<1.5pe cut outside inefficient region is used

 - also a hole cut is applied, needs to be added also to SIMC analysi

- MM_K plot

  - Black=Center  Red=Left  Green=Right

  - Lambda peak looks fairly clean, reasonable normalized yield consistency

    between the three settings

  - *NEED TO DO* a Lambda yield vs HGC cut study

Heep data/MC yields under various conditions

- as presented at the last meeting, there is a significant linear trend to the

  Data/MC ratio vs Q2

- various investigations to see where this is coming from

- applying a SHMS Dipole Exit Cut

  - DG: need to apply the same cut to SIMC data

- PID cuts

  - DG: suggests to remove all SHMS proton cuts

- Heep data up to Q2=7.5

  - this is a significantly higher Q2 than we have done in past Heep-check

  - can try a different Heep parameterization in SIMC, follow instructions in

    Wenliang Li's PhD thesis

Sorting out issues with Bill's LT-separation code

- come questions about seemingly arbitrary parameterization need clarification

  - we will have a separate meeting on Friday at 14:30 Eastern about this

    Meeting ID: 954 3340 5506

   Passcode: 901353

- testing the code with Q2=2.1 data

- various issues with batch submission scripts failing, even though jobs run

  fine from terminal

  - Casey suggests to use -phase and -antecedent parameters in SWIF job

    submissions

Ali

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pi+Delta0 BSA analysis

- earlier, DG suggested to investigate rho+N->pi+pi0N contribution in addition

  to SIDIS

  - SIMC simulation very inefficient

  - took ~3 days to get 200k events

- comparision of rho and SIDIS MC (weighted distributions)

  - rho peaks at lower MM~1.15 than SIDIS (MM~1.4)

  - looks like rho will be useful in obtaining a better fit of MM region to

    left of Delta

- t-distribution >0 for rho 

  - DG: confirms that for his rho files, t<0, so there must be a sign issue

  - some discussion that it migt be a reconstruction code issue, Ali will

    investigate

- tentative strength of rho

  - DG: initial guess from prior SIDIS analysis is that rho is 10-20% of SIDIS

  - this seems a good guide for Ali's initial fitting

- discussion about large pi+n tail and how to deal with it

  - NH suggests to arbitrarily scale up the pi+n MC to fit the tail, even

    though it would dramatically over-shoot the neutron peak

  - GH: before contemplating this, we really should deal with the issue that

    the data MM resolution is worse than predicted by MC

- DG: made some plots earlier of MM versus FP variables, found some

  correlations

  - will try to look at this in a bit more detail

  - AP will direct DG to where the newest ROOT trees are located

Vijay

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- no plots, but working on LT-sep analysis, will attend tomorrow's meeting

Alicia

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- working on slides for Hall C meeting, need to have draft slides ready for

  Thurs Jan 11

- sorting out some out of memory errors in python analysis scripts

- looking at PARTONS GPD code, manually change contributions of GPDs as per

  Stefan Diehl's paper

Nacer

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KaonLT Q2=0.5 drift chamber calibration checks

- Junaid helped adapt code from PionLT to KaonLT

- initial plots of SHMS drift distance spectra

  BLUE=after calib  RED=before calib

- red has some significant deficits for d<0.1, particularly SHMS 1v,1u planes

- blue looks better in some spots, but SHMS 2v planes indicate new t0 offsets

  are needed, deficit for d<0.1, and residual distributions actually worse than

  red

  - need to rerun code with t0 flag off, Junaid will give info

Next Meeting

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- Thur Jan 11 @ 15:00 Eastern/14:00 Regina

  - KaonLT will go first

Please fill out the poll at:

  https://www.when2meet.com/?22907632-UJ4DV

So far, it looks like Thursdays at 14:30 Eastern/13:30 Regina is best