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Feb 29/24 PionLT/KaonLT Analysis Meeting Notes

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(Notes by GH)

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Today: KaonLT will be discussed first

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Please remember to post your slides at:

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https://redmine.jlab.org/projects/kltexp/wiki/Kaon_LT_Meetings

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Present

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

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Nacer Hamdi, Alicia Postuma

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CUA  Richard Trotta, Casey Morean

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JLab  Dave Gaskell

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FIU  Pete Markowitz

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Richard

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 PhD thesis has now been submitted to the committee for review.

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Congratulations on this milestone!

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LTIteration Script Issues

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 uncertainties for unseparated d2sigma behave weirdly when iterating, while

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the R=model/data ratios behave normally

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 statistical errors on d2sigma get much smaller after an iteration

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 clearly there is still a bug somewhere

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 GH: it sounds like the way the Rerror is propagated to d2sigerror is the

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issue

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Plots of d2sigma vs phi are shown for various settings at high, low epsilon

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 a MM cut is now applied: 1.1<MM<1.18

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 Q2=3.0, W=2.32 is particularly weird, low epsilon significantly larger than

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high epsilon

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 for this setting P_HMS=6.6 GeV/c, so maybe that's a hint

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 Ali: the Heep offsets for this setting overcorrect the MM peak, i.e. moves

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it too far

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Plots of sigL, sigT vs t shown

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 for some settings sigL is plotted instead of sigL, due to the low

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epsilon>high epsilon issue

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 clearly this will need significantly more investigation

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Ali

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 was sick last week, only getting back on track now

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Clean pi+,p data for Richard's PID leakage subtractions

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 finished analyzing pi+ for 3 of 5 kinematics, data ready for RT subtraction

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 proton will be done soon

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 no HGC cut used at all

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 RT will apply the HGC hole cut to his sample, confirms that it will be

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straightforward to implement

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 RT still has to resolve the 5cm HGC hole cut shift issue reported a few

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weeks ago

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 RT thinks the x_HGC, y_HGC coordinates were not implemented correctly,

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will return to this soon

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Resuming SIMC resolution study, nothing to report yet

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Alicia

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HMSdelta correction update

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 had a discussion with DaveG a few days ago, after finding that application of

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DG's deltacorrection did not yield the expected improvement to MM resolution

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 found that DG's MM calc was based on the old 6GeV/ENGINE formula

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 Alicia is using hcana calculation, and this appears to be the cause of the

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difference

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 DG is trying to figure out what exactly is different between the two MM

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calculations

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 hcana: takes x',y' and spectrometer angles, converts to spherical theta,phi

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and calculates PM components

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 ENGINE: calculates PM components in spectrometer x',y' system and converts

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to target coordinates, but does not use spherical coordinates at any step

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 DG: calc in hcana is harder to follow, can't see where the difference is,

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in principle both calculations should be equivalent

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 AP: tried to recalculate MM on her own, also agreed that old method is

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easier to understand

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 her calculation does not fully reproduce hcana either

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 Alicia shows a plot from script, sees no correlation between delta and hsxpfp

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for P_HMS<5 GeV/c

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 Q2=2.1, W=2.95, P_HMS=5.292: starts to see a correlation

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 Q2=3.0, W=2.32, P_HMS=6.59: a definite curved correlation is seen

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 will have to apply a correction for these two settings, but it needs to be

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different than what DG had found

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 DG: for P_HMS=6.59, are we 100% sure we're using the correct Matrix

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Elements for this setting?

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 Ali goes to check, confirms that the correct ME are used for both his and

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Alicia's analyses

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 Jacob was looking at finalizing the high HMS momenta ME, Holly is looking

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at higher P_H MS w/NPS students

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 clearly there is an issue that needs further optimization

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 Implementing the HMSdelta correction for high P_HMS

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 DG: can't just correct MM, all kinematics are affected, in principle will

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affect the tbinning for these settings, as events will migrate from one

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bin to another

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 rather than Alicia continuing with her reconstruction script, it will be

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better to modify hcana to include the correction for high P_HMS, so that

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all kinematics are handled consistently

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 DG: suggests fitting a quadratic, but only apply to a certain region of the

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HMS focal plane

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 Alicia: maybe a piecewise linear function? Will think about what works

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best

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 *CONCLUSION* Alicia will first determine the needed delta correction then

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implement in hcana

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Vijay

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 Just returned from EIC workshop in India, starting analysis again and yield

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ratios

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Shows interesting Lattice QCD calculation from workshop

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 Swagato Mukherjee (BNL), Q.Shi will be first author, not yet submitted

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 LQCD calc for both pi+ and K+ to Q2~35

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 calc indicates that both Q2*Fpi and Q2*Fk will remain high through the full

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Q2 range, with no significant decrease to pQCD curve

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 not surprisingly, the Lattice errors are fairly large

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 we definitely need to keep a look out for the final calculation

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Nathan

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Working on PionLT Lumi study and plots for the SHMS NIM paper

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 looking at what PID cuts to apply for the Lumi study, which also generates

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the needed plots for the paper

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 SHMS single arm e' Lumi scan

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 NGC vs Calorimeter

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 NGC vs Aerogel

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 NGC vs HGC

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 GH: suggests to apply NGC vs Calor cut and look at the others with this cut

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applied to see what is removed before deciding whether the other plots add

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anything extra to the PID selection (useful also for the paper)

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 HGC, NGC efficiencies vs delta

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 efficiency plots vs X_cer still in progress

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 HGC, NGC, Aerogel 2D efficiency plots vs X,Y_FP

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 see hole in the HGC, NGC and tray boundaries in Aerogel

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 LH+ production data PID plots shown

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 LD also quickly looked at, sees large e peak in SHMS

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Next Steps:

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 make sure sure Lumi script is working properly

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 RT will meet with Nathan separately to go over what changes he needs to

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make to Lumi script

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 In addition to changes since 2021, Nathan will have to modify the script to

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handle Lumi runs where only one arm data at a time (should be straightforward)

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 apply proper cuts on data ranges

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Junaid

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Working on PionLT efficiency studies

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 investigating outlier runs, removed bad runs from plots

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 most of these had beam trip issues

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 also some runs with quadrupole trips

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 DG: how do you remove these runs from the analysis?

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 run list is modified, so these runs will never be replayed in future jobs

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 tracking efficiency studies nearly complete

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 generating beam cut files from replays

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 will be included in future replays

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Heepcheck analysis preliminaries

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 looked closely at the kinematics for all HeepCoin settings in 202122

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 selected 9 of the 16 settings for further study, based on the angle and

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momentum settings

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 GH: the other 7 settings will be kept in reserve for a future student to

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look at

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 did not look at list of Heepsingles runs yet, it's a very large list of

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settings

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 will first look at the Heepcoin results and from there decide which

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Heepsingles settings are helpful to look at

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Nacer

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Efficiency studies for 3.8, 4.9 GeV KaonLT data

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 Plot of CPULT vs COIN trigger rate

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 sharp drop off seen above 2.8 kHz

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 looked at the outlier run near 2.8 kHz, where the CPULT relation kink

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 no comment in run sheet, will look next at hclog

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 DG: are the rates corrected for the beam off time?

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 will have to look more closely into this

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 Plot of SHMS_pion_sing_TrkEff

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 vs SHMS_3/4 trigger rate

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 2 outliers seen

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 vs S1X rate

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 3 outliers seen

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Next Meeting

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 Thur Mar 7 @ 15:00 Eastern/14:00 Regina

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 PionLT will go first

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 USA daylight savings switch is following week

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 meeting time will remain at 15:00 Eastern, which switches to 13:00 Regina

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 GH will send Zoom invitations up to end of August

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