Mar 6/25 PionLT/KaonLT Analysis Meeting Notes
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                                (Notes by GH)

                     Today: PionLT will be discussed first

Present
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Regina - Garth Huber, Ali Usman, Muhammad Junaid, Alicia Postuma, Nacer Hamdi
FIU - Pete Markowitz
JLab - Dave Gaskell
Ohio - Julie Roche
Virginia - Richard Trotta
CSULA - Konrad Aniol

Junaid
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PionLT Heep Studies
- using global offsets presented last week
- Data/MC ratios using Nathan's LH2 boiling factor
  - MM cut applied to exclude pi0, same cut value for all settings
  - R=0.89-1.020, average value ~0.95, which is MUCH better than earlier
    analysis
  - will have to apply Alicia's proton correction (~5%), and Nathan's final
    rate corrections (undetermined but will be small).  With these applied, the
    ratios will be quite close to 1

  - Dave: intrigued by varying ratio for the three 6.395 GeV settings,
      variation from mean is about +/-0.05, which is much larger than the
      statistical error
    - we look at the setting kinematics, no obvious trend with anything
    - pHMS is not in saturation region

  - Dave: one Heep setting has evidence of a shift in HMS-delta between Data
    and MC (P_HMS=3.7 MeV, theta=31.6)
    - this might indicate that the swap in calculating offsets between
      theta_cent and P_cent is not quite right
    - we look at another setting to see if there's a consistent trend
      P_HMS=3.8 MeV, theta=29.7 setting showed no HMS-delta shift even though
      the setting kinematics are very similar
    - Garth: from everything he's seen, there appears to be a certain amount of
      non-reproducibility from one setting to another.  For example, when
      returning the spectrometer magnets to a previous field, the currents
      usually differ by 1A or so from the previous value.  It might be
      something along these lines
    - Dave: the beam energies are different between these two settings, and
      those are independent energy measurements, so that is a more likely
      source

  - Julie: we should take a look at the Heep setting with R=0.88
    - this shows no evidence of a shift, just a normalization difference
      - JM: will check if any bad runs were included by mistake

  - some discussion whether any further optimization is needed of Heep cuts
    - Dave: the difference between data and MC left of the W peak is due to
      mismodeling of resolution in SIMC.  It's not experimental background and
      these events should not be removed as they're valid events

Next steps:
- started working on Q2=3.85, W=2.62 physics setting with 2 epsilon points
  - param files updated and pushed to GitHub

Alicia
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Discussion about BSA PLB updates
- already started entering the article metadata in the journal server
- created a Mendeley Data Repository for spreadsheets of numbers and other info
  that will be cited from the paper
- planning to submit no later than Monday

Nacer
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KaonLT Q2=0.5 analysis
- working on t-binning, some jobs still running so no plots to show yet
- some discussion about binning strategy
  - Richard: absolute minimum of 1000 events per t-bin, 2000 is better
  - Garth: it would be great if we could get 5 t-bins, no need for many more
    than this, it would be better to instead have more phi bins
  - will start with 10 phi bins

Richard
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KaonLT Q2=4.4, W=2.74 LT-separation
- did some checks to resolve the sigT<0 for lowest t-bin
  - found that this bin had significant pion contamination
  - raised lower limit of bin from 0.35 to 0.40 to remove pion background
  - as a result, sigT is closer to zero now for this bin
  - upper limit of this bin was unchanged at 0.85, will raise it higher as well
    so the bin has more statistics, and then will do some iterations

- Garth: a bit surprised that the fit (red) curves for LT, TT don't go to zero
  as -t -> -tmin even though the functional form has sin(theta*) dependence
  - Richard: over the t-bins, theta*=22-31deg
  - Garth compares to 6 GeV data, where theta*=2-13deg
  - maybe it's a kinematic effect at the higher energy, but it's a bit
    surprising that theta* is so large for the lowest t-bin
    - Richard will check
Next Meeting
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- Thur Mar 13 @ 16:30 Eastern/14:30 Regina
  - KaonLT will go first

- NOTE: on Mar 9 USA moves to DST, so we will need to move to 16:30
  Eastern/14:30 Regina for the period March 13-April 10
  - after that, we can return to 15:30 Eastern for the convenience of our USA
    colleagues