Kaon_LT Experiment

                 Feb 23/23 PionLT/KaonLT Analysis Meeting Notes

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                           (Notes by GH and SJDK)

                    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 - Stephen Kay, Garth Huber, Ali Usman, Alicia Postuma, Nathan Heinrich,

   Vijay Kumar, Love Preet, Muhammad Junaid

JLab - Dave Gaskell

Ohio - Jacob Murphy, Julie Roche

CUA - Tanja Horn

Dave G Updates (on behalf of Richard)

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EM/PM calculations

- Met with with Richard on implementing post-SIMC script

   - Found a few bugs and things that needed to be adjusted

   - Once meeting was done, seemed to be working ok

   - Some distributions were looking a bit weird, but seemed to be resolved,

     particular for EM

   - don't know yet on how well the new SIMC calculations reproduce data

Nathan Updates

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Ref/Det time cuts

- Tested on some settings with online analysis scripts

- continuing on LD- setting that got less events than online analysis

   - Checked cuts, all looked ok

   - reran online scripts with identical cuts to new analysis with exception of

     Ref Time

   - New cuts reduce # events in LD- Q2=3.85, W=2.62, low eps setting by ~20%

- Other settings don't see the same effect though, get more after updating

  ref/det time cuts

   - For LD- Q2=3.85, W=2.62, center, hi eps the #counts goes up slightly

   - For LH+ runs checked, the events also go up

- For LD- setting with reduction, seems uniform across all plots, see similar drop

  for all types of events - prompt/random

   - NH thinks it could be due to a PID detector calibration shift with new

     cuts, and the proportion of good events passing cut has gone down, would

     need recalibration and adjustment of cuts to be sure

   - SK: Should investigate quickly to see if it's a uniform reduction or one

     particular run/set of runs causing weird issues

   - Setting was in two parts, separated by several days (i.e. we came back to

     get more statistics after completing other parts of run plan)

      - GH: Should absolutely compare each part before/after applying new det/ref

        cuts

      - Split the 74 runs in this setting into batches? 

         - Day by day? OR Shift by shift?

      - need enough statistics in each batch to be able to draw conclusions

   - in fact, for *all* settings divided into multiple parts by time, the

     parts need to be looked at separately, and only combined after we are

     sure everything is consistent

      - this includes all detector calibrations, etc

   - *** this study can be done in parallel with detector calibrations, but

     *** it is essential that we understand what is going on with this LD-

     *** setting, as a 20% effect is huge!

Jacob Murphy

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- No elastic delta scans yet

   - Recovering from an illness

   - Working through some old hard coded scripts, getting them going for PionLT

Junaid Updates

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- Busy with NP course

   - Midterm next week

- No report on calibrations yet

Ali Updates

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HMS Cal/Cer Efficiency - HeeP Singles Studies to get clean sample of electrons

- Heep #1 Run 6600 - Ebeam=3.835, Phms=2.835 GeV/c

   - Cer 97.20%, Cal 99.63%

   - Much better Cherenkov efficiency

   - Calorimeter v.good

- Heep #2 Run 6603 - Ebeam=3.835, Phms=2.713 GeV/c

   - Cer 97.31%, Cal 99.64%

- Heep #3 Run 6608 - Ebeam=3.835, Phms=2.583 GeV/c

   - Cer 97.34%, Cal 99.65%

- Heep #4 Run 6680 - Ebeam=4.933, Phms=2.583 GeV/c

   - Cer 97.46%, Cal 99.47%

- Heep #5 Run 7852 - Ebeam=6.190, Phms=3.709 GeV/c

   - Cer 97.12%, Cal 99.37%

- Heep #6 Run 7857 - Ebeam=6.190, Phms=3.491 GeV/c

   - Cer 97.17%, Cal 99.29%

- Rate Dependence plot, eff vs rate (S1X)

   - Cherenkov eff seems to have a fairly slow drop off with rate

   - Calorimeter has no obvious trend

   - Not much of a spread in S1X though, ~35 kHz to 70 kHz

   - Physics rate range is a bit higher, up to 150-200 kHz

   - DG: considers this study to be ~90% complete

     1) would be nice to get a firmer handle on the rate dependence

       - are there physics data at higher rate with favorable pi-/e-?

     2) need to check for dip in HMS Cer efficiency where mirrors overlap

       - this hasn't been checked yet after the mirror replacement

       - 1D plot of Cher eff vs X_cer should be sufficient

   - Cal eff is often parameterized vs Phms, as the energy resolution changes

   - Cer eff is usually just a fixed number, unless there's a rate dependence,

     in which case this rate dependence needs to be understood

   - NH: a *plot* of Cal eff vs. Phms would be useful, maybe this would explain

     some of the outliers in the rate dependence plot

- Next step is to finalise PID

   - For coin events, pi- background will be removed with CT cuts etc

   - Should have a fairly clean electron sample with coincidences to find a

     good efficiency a higher rate

Vijay Updates

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Phi and t binning in progress, full report next week

- Yield calculation per (t,phi) bin

   - Will have the rest next week hopefully

Alicia Updates

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- 2nd place in best overall presentation at WNPPC (Winter Nuclear and Particle

  Physics Conference) in Banff, Alberta

   - Well done Alicia!

- Circulated abstract for CAP

   - Feedback/comments appreciated

- Depending upon word/character limit, maybe clarify "Transition regime" in

  abstract

Next Meeting

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Thur Mar 2 @ 17:00 Eastern/16:00 Regina/15:00 Mtn/14:00 Pacific

- KaonLT will go first

USA savings time starts Mar 12, so we need a poll to find a meeting time.

GH will circulate one soon.