May 9/24 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, Ali Usman, Alicia Postuma, Muhammad Junaid, 
   Nathan Heinrich, Vijay Kumar, Zach Sullivan, Nacer Hamdi
JLab - Dave Gaskell
York - Stephen Kay
FIU - Pete Markowitz
CUA - Tanja Horn, Casey Morean
CSULA - Konrad Aniol

Vijay
-----
Low Q2 PionLT LT-separations
- changed functional form:  sigT=A+B(ft_av) where ft_av=t/(abs(t)+0.139570^2)^2
- still using sigL=A*exp(Ct)
- shows results of new iterations:
  - phi distributions at high, med, low epsilon
  - sigT,L,LT,TT versus -t

Alicia
------
Update on pi+n BSA paper
- runs through summary of draft paper on OverLeaf
- asks a few questions on technical details for paper

Tanja
-----
High Q2 KaonLT LT-separations, shows a few new plots on behalf of Richard
- now including data from Left,Right,Center settings at Q2=3, W=3.14
- lower t-bins have better fit to phi distributions now
- plot of sigL vs -t show evidence of K+ pole, which is great
- sigT is flat, and fairly small magnitude, sigT<sigL for lowest -t bins
  - probably due to large W 
- GH: *some sigT errors look small*, particularly in comparison to sigL, should
  be checked
- now starting to look at Q2=2, W=2.92 data

- draft slides for Richard's China talk on EIC meson structure simulations will
  hopefully be distributed soon

Ali
---
piDelta BSA
- Q2=5.5, W=3.02
  - as before, large -t region (1.05-1.60) is excluded
  - MM fit for 8 t-bins
    - Center: 8 bins, Right: 4 bins, Left: fit done for 2 bins, other 2 bins
      have low stats and narrower MM range, making piDelta fit unreliable
  - first showing of BSA vs phi for these data
    - Bkd subtracted Data (Data-SIDIS-pi+n_tail) is integrated from 1.11-1.4
    - in systematic study, piDelta MC will be integrated as well
    - will make a plot of Bkd subtracted Data to compare to piDelta MC peak
      shape
  - compare BSA to pi+n for 0.4-0.8 t-range, both have magnitudes ~0.1, and
    same sign

- Q2=4.4, W=2.74
  - exclude large t-region: 1.00-1.60
  - Center: 8 phi-bins, pretty good fits
  - Right: fit 4 phi-bins, very low stats in other phi-bins
  - Left: can fit all 4 phi-bins (unlike Q2=5.5)
  - BSA vs phi has magnitude ~0.15, also similar to pi+n for similar t-range

  - Alicia can do a rebinned pi+n BSA for identical t-range to piDelta to make
    the comparison more valid

- work in progress for remaining 3 settings
  - preliminary shape study shown for Q2=3.0, W=2.32
    - exclude large -t 0.90-1.60
    - Right: 8 phi-bins
    - Center: only 6 phi-bins populated
    - Left: 4 phi-bins

Garth
-----
SIMC mods for pion re-scattering in SHMS/HMS Collimator
- to enable, use the following flags at the end of your input file:
    using_HMScoll = 0     ;  pion scattering in HMS collimator
    using_SHMScoll = 1    ;  pion scattering in SHMS collimator
  - 0=rescattering OFF  1=rescattering ON

- Dave has accepted GH's changes, now in main branch of SIMC
  - confirmed that the effect is small, at least for SHMS
  - GH shows MM comparison plots for two PionLT settings:
      Q2=5.0, W=2.95, eps=0.38, SHMS=center, p_SHMS=6718.9
      Q2=3.85, W=2.02, eps=0.58, SHMS=center, p_SHMS=3493.1
    - only a slight broadening of the MM distribution is seen, slightly more
      for p_SHMS=3.5GeV/c compared to 6.7GeV/c

- Dave mentions that iFarm is transitioning to ALMA-9
  - present version of SIMC will not work on ALMA-9, due to changes in gFortran
    specifications for special structures
  - changes are ready to go, needs to push
  - for now, please be sure you select RH7 nodes
  - RH7 going away completely by end of June
  - longer term, Dave will consider to replace the structures with a more
    conventional storage approach, to avoid the compatibility issue

Nacer
-----
Low Q2 KaonLT analysis
- downloaded SIMC today and starting to set up for Heep simulations

- found Lumi cryotarget boiling and CAL/Cer Effs with help of Ali

Nathan
------
PionLT Lumi studies
- after updating the BCM calibs, look again at the rate dependence studies
  - runs 16738-16746 1 arm-at-a-time data
  - TLT looks sensible (95-100%)
  - rate dependences generally mild, so optimistic that the studies will go
    well
  - clear evidence that the BCM offsets NH determined earlier will need to be
    revised, most likely a bit smaller, which is good

- 3/4 Trig rate dependent efficiency will need to be added for Scaler analysis
  - some discussion with Dave on not needing to apply this in event analysis, 
    as PID cuts clean things up

- getting Zach a JLab computer account, he will need to do some training first

Junaid
------
- returned late last night from JLab, found the trip to be very useful
  - had a detailed meeting w/Richard on analysis code

PionLT Heep offsets
- will add a systematic error to fit for OOP offset, as GH did for KaonLT
- working on replaying data with in-plane offsets determined by GH

Stephen
-------
SHMS NIM paper updates
- draft is nearly ready, hoping to be done in time for Quarterly analysis
  meeting in June
- a few more plots needed on performance of aerogel & tracking
  - Nathan and Junaid will follow up
  - some useful plots on NGC performance might be found in Abishek's thesi

Next Meeting
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- Thur May 16 @ 15:00 Eastern/13:00 Regina
  - PionLT will go first