Kaon_LT Experiment

                 July 6/23 PionLT/KaonLT Analysis Meeting Notes

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                                (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

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Regina - Garth Huber, Ali Usman, Muhammad Junaid, Nathan Heinrich, Vijay Kumar, 

   Alicia Postuma

CUA - Richard Trotta, Tanja Horn

JLab - Dave Gaskell

FIU - Pete Markowitz

Ohio - Julie Roche

CSULA - Konrad Aniol

Richard Updates

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Meeting with Peter Bosted is tomorrow at 13:00 Eastern

   Zoom Mtg ID: 815 5260 0153

   Passcode: 746974

HGC cuts and efficiency calculations

- applied one of Vijay's cuts, but it looks too small in comparison to hole in

  NPE vs (x,y), the data are 10.6GeV, maybe the cut is for 8 GeV?

  - Vijay drew several versions of the cuts, needs to look them up

- Vijay thinks he drew the cut on Efficiency vs (x,y), not NPE 

  - will look up older reports, and meet with Richard on this after meeting

    with PeterB

BCM calibrations

- DG: PeterB doesn't use the most updated analyzer, it does not have Dave

  Mack's high current non-linearity correction in it

  - if you apply PeterB's BCM correction, you are double-applying the

    non-linearity correction

Ali Updates

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- updated standard.database to read in proper BPM files for each run period

- setting up scripts for LT-analysis

  - want to finalize t-binning as Alicia needs this too

    - needs diamond cuts to be applied first

  - want to compare cuts w/ Alicia, should overall be similar, except for HGC

    cut

    - AP reminds us that she will do a HGC cut dependence study, but no HGC cut

      will be used in the final results, as the asymmetries are very similar

      but with larger errors

  - running SIMC for pi+n, pi+SIDIS, pi+Delta0

- working on offsets

  - reran Heep singles w/ updated BPM, to give more data points at mid-HMS

    momentum

Vijay Updates

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Working on HMS calorimeter efficiency study

- DG had suggested plots vs p_HMS for fixed cut

  Left: >0.2 cut  Right: >0.7 cut

  Three data sets: p_HMS=0.448, 1.35 2.25 GeV/c

  - efficiency is high and stable for >0.2 cut

  - efficiency for >0.7 cut is very low at 0.448 GeV/c

  - DG: apparently Dave Mack found that FADC threshold was set too high, caused

    inefficient calorimeter regions for P<1 GeV/c

    - had forgotten about this, now agrees that it's okay to use a lower cut

      for low HMS momentum

    - does Vijay have a calorimeter plots that we can look at

      Yes, but needs a few minutes to find them

Alicia Updates

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Waiting on t-binning from Ali

Working on PARTONS GPD library

- sigl, sigt, siglt, etc are private functions only

- modifying code to implement new classes to allow these cross sections to be

  outputted

  - since DEMP reactions are only recently implemented, unlike DVCS, only

    asymmetries are output so far, and thinks it's likely the authors haven't

    gotten around to doing this yet

  - JR: suggest reaching out to the authors to see if they have any suggestions

   or warnings on doing this

- will have a tutorial next week on running PARTONS

  - Julie is interested, we will circulate a Zoom link when it's scheduled

Vijay (2)

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Shows plot of H_cal_Etottracknorm

- looks very clean, no pion background even below <0.2 at 0.448, 1.35 GeV/c

- applied cuts: HMS Cherenkov, CoinTime prompt peak

  - DG: at these momenta, the TOF differences between pions and electrons are

    large, we need to see what the plot looks like when accidentals are

    included, as accidental coincidences cut could cause issues

- Vijay will quickly replay one run so we can see the plot

Nathan Updates

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More work on SHMS HGC calibrations

- more data points so we can see the trends in the data

  - the decreasing trend up to run ~13900 looks to be real

  - this apparently corresponds to when 7.9GeV beam began

  - after this, the calibrations are stable all the way to the end of the 2022

    run

- suggests to take a constant calibration for all runs after start of 7.9GeV

  beam to end of 2022

  - for sloping part, fit calib data with a line and calculate middle value for

    a setting

  - TH: suggest two plateaus (beginning and end) and a linear part in between

    PMTs 3,4 show the early plateau more clearly compared to PMTS 1,2

- GH asks about some gaps in the plots

 - plot shows calib setting by setting only, with point at the earliest run

   number

 - GH suggests that for settings taking longer than a day that the period be

   sub-divided, and calculate from the linear trend for each period, maybe even

   for each individual run number if that is easier to set up

- Some discussion on what is causing the decreasing trend in the calibration

  - we know the HV monitor was stable, so the PMT gain should have been stable

  - JR: is the HGC signal going through a pre-amplifier?

    - DG: for sure the NGC was, need to check about the HGC

  - GH: please try to look at the hclog during the period while 9.2GeV beam was

    being tuned (only a few shifts) and see if there is a log entry on if

    anything was adjusted

Junaid Updates

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Updated DC calibs for both spectrometers

- will post slides and sample plots (shown last week) on RedMine

Working on HMS calorimeter

- fixing path issues

- hoping to see some plots next week

Jacob

-----

- Julie informs us that Jacob is taking a medical leave of absence until

  December

  - we hope he is doing okay

Vijay (3)

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Replay of one 2.2 GeV/c run is completed

- plot w/o CoinTime cut shows small grass <0.2, with a minimum at 0.3 (on log

  scale)

- DG: agrees that a cut at either 0.2 or 0.3 is reasonable

  - thanks Vijay for showing all of these plots on a short time scale

Next Meeting

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- Thur July 13 @ 16:00 Eastern/14:00 Regina/13:00 Pacific

- PionLT will go first