Jan 9/25 PionLT/KaonLT Analysis Meeting Notes
                 ---------------------------------------------
                                (Notes by GH)

                     Today: PionLT will be discussed first

Present
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Regina - Garth Huber, Ali Usman, Alicia Postuma, Nathan Heinrich,
   Nacer Hamdi, Vijay Kumar
Ohio - Julie Roche
JLab - Dave Gaskell
Virginia - Richard Trotta
FIU - Pete Markowitz

Nathan
------
PionLT luminosity studies
- plots of singles scaler yield vs current and rate
- correlation with rate is much clearer than vs current
- HMS scalers give nice straight line vs current
  - ELLT checks done, now get 2.8%/100uA slope for LH2 boiling

- apply this boiling corr to SHMS, HMS scaler yields and replot vs rate
  - get a slope of 3.8%/MHz, consistent for both HMS and SHMS
  - interestingly, without the LH2 boiling correction, the HMS has a different
    rate dependence due to the lower rates at high current.  When the LH2
    boiling corr is applied, HMS and SHMS look pretty consistent
  - *NB* need to confirm whether 3/4 or ELREAL rate is used on x-axis

- took difference of global fit slope and individual settings, with statistical
  error removed in quadrature, as an estimate of the systematic uncertainty
  - obtained +/-0.7%/MHz
- *NB* will apply this rate correction to Carbon Lumi data to confirm there is
  no anti-boiling
  - can adjust low current offset slightly if needed if anti-boiling is found

- Dave: this suggests there is a source of DeadTime that we're missing
  - we see it in scaler analysis, so it would have to be in the trigger legs,
    not FADC or CPU
    - most likely culprit would be the 3/4 trigger
    - *NB* Carlos did find some anomalously high DeadTimes, Dave Mack did a
      study in response.  
      Take a look at:
      1. Dave Mack's presentation on explaining the larger than expected dead
         time from Carlos' data:
         https://hallcweb.jlab.org/doc-private/ShowDocument?docid=1063

      2. Casey's application of this calculation:
         https://misportal.jlab.org/ul/publications/downloadFile.cfm?pub_id=20620
         Page 88 or so.

- Julie: in your plot vs rate, is there any indication of a flat part at low
  rate?
  - need to recheck low current offsets first
  - don't think the evidence is compelling

- Coin Lumi vs rate and vs current
  - *NB* plotted vs COIN rate, but if the DeadTime is in the trigger leg, it
    needs be the equivalent 3/4 rate integrated over both arms

- expecting studies to be wrapped up in 1-2 weeks
  - *NB* Richard, Vijay should apply Nathan's rate dep to their Lumi data and
    see what they get

Alicia
------
BSA revisions, PLB vs PRC
- journal length limits are very different
- will prepare revisions assuming PLB and then see if can address the referee
  comments in that limit, or if we need PRC length instead

Nacer
-----
KaonLT yield scripts
- found that MM is shifted ~50 MeV compared to SIMC
  - still trying to figure out what is wrong
  - Garth: suggests to start by checking standard.kinematics, since it must be
    something substantial
  - *NB* Ali (better suggestion): maybe there is a typo in the kinematic
    offsets, and they are off by an order of magnitude

- *NB* Garth: suggests to compare to online MM plots at
  https://hallcweb.jlab.org/wiki/index.php/Kaon_LT_Status_Page#Kaon_LT_Physics_Status_at_Ebeam_.3D_3.8.2F4.9_GeV
- these were generated with the online version of standard.kinematics, so the
  comparison might eliminate some possibilities
- online analysis script integrated a region around the Lambda MM so it would
  have been noticed quickly if the Lambda peak was shifted by 50 MeV then

For the rest of the meeting, we reviewed draft presentations by Richard and
Vijay

Next Meeting
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- Thur Jan 16 @ 16:00 Eastern/15:00 Regina
  - KaonLT will go first

  - we also need to check if people's availability has changed after Jan 16, or
    if we can keep this time until daylight savings time change in March