Sept 19/24 PionLT/KaonLT Analysis Meeting Notes ----------------------------------------------- (Notes by GH) Today: PionLT will be discussed first Please remember to post your slides at: https://redmine.jlab.org/projects/kltexp/wiki/Kaon_LT_Meetings Present ------- Regina - Garth Huber, Nathan Heinrich, Muhammad Junaid, Alicia Postuma, Ali Usman, Nacer Hamdi CUA - Tanja Horn Virginia - Richard Trotta JLab - Dave Gaskell, Peter Bosted Ohio - Julie Roche CSULA - Konrad Aniol Nathan ------ PionLT Lumi Analysis - new plotting scripts ready, working on getting COIN Lumi analysis working - hoping to show results next week Junaid ------ PionLT Heep Analysis - Diagnosing Low SHMS 3/4-Hodo Efficiencies - trying to understand if drop in efficiency at higher momentum is due to rate - Subdivide 3/4-Eff data into momentum ranges and plot vs rate - Heep Runs 11860-16517 - no obvious rate dependence, drops in eff are in groups for certain settings - emails w/ Mark re Low 3/4-Effs, he is taking a closer look - checking EDTM live times - >99% for both Heep and Physics - differently from KaonLT, the EDTM-LT seems to be reliable for PionLT, which is good news - updated Data/MC Ratios - recalculating ratios using 3/4-Eff instead of Report File eff for higher momentum, using report file 3/4-Eff for P_SHMS<2.5 GeV/c - get ratios of 0.995-1.025 before applying proton absorption correction - moves in the right direction, but ratios still too high - LH2 boiling correction - using Richard's correction, about 6%/100uA - Dave: note that Dave Mack got 2.26+/-0.30%/100uA from Fall 2018 scaler analysis - *NB* should look more closely at this, it would help the ratios Next steps - implement effective charge uncertainty in yields script - start working on proton absorption correction - will attend next weekly Optics Meeting to see the status of higher P_HMS matrix elements Richard ------- Diagnosing weird ratios in KaonLT High Q2 L/T-separations - running tests using one of Vijay's settings, to look for differences between his analysis and Vijay's - Q2=0.38 low eps, center setting - shows plots of pi+n MM peak compared to version in Vijay's thesis - BLACK=data RED=MC - Vijay's data and MC are centered at correct value, reasonable agreement on width - Richard has MM peak shifted to left, by different amounts for data and MC - Tanja: *NB* suggest to try using Vijay's ROOT trees directly, instead of new hcana analysis, to diagnose what's wrong - will also look into CoinTime cut, since there is a shift in distro between Vijay and Richard Alicia ------ BSA pi+ paper: Implementing referee suggestions - will use new title suggested by editor and referee - moved A_LU definition earlier in paper, also definitions for sig_0, sig_LT' - still need to calculate pi+ det efficiency and purity numbers - adjusted some paragraphs so systematic uncertainty discussion is in 1 para - chi-square analysis for theory vs expt, and discussion on model significance in progress - 1st point of data extends to left of theory region, i.e. they have different -t_min, because theory is evaluated only at central kinematics, and not separate (Q2,W) of each point, for this reason, it is excluded from the chi-square calculation - YCK1 has best chi-square - VR is 2nd best fit for our data only - at Q2=3.0, where CLAS data at higher -t is included, VR does worse - could include chi-square table for different models in Supplmentary Material - B-G Yu replied that he will let us say what we want about the model significance - expecting to circulate a new draft next week Ali --- KaonLT pi+Delta0 BSA analysis - working on thesis - redoing A_LU and sig_LT' plots, will include CLAS pi0Delta++ results (with sign flipped) - input received from PeterB re piDelta MC peak shape - wanted to make sure we're using the updated algorithm in SIMC - includes a lookup table for relativistic corrections to simple BreitWigner shape, which should result in improved agreement with data - responded that we're using the latest SIMC version - there is a bit of mismatch between data and MC on left side of Delta, due to tail coming from exclusive pi+n - will assess a systematic uncertainty on the tail mis-fit - will be at APS-DNP meeting in early October, will circulate slides ahead of next week's meeting Nacer ----- KaonLT Heep analysis - plot of Hodo-3/4 efficiencies vs Trigger Rate - getting 92-98% efficiencies - no clear correlation with rate - plot of Hodo-3/4 efficiencies vs P_SHMS - planes 3,4 have particularly bad 3/4-Effs - same curious drop at higher momentum as in PionLT - Dave: *NB* Log entry from Simona suggesting higher momentum protons should have higher efficiency in quartz bars: https://logbooks.jlab.org/entry/3564126 - Ali shows plot of 3/4-Eff vs SHMS-Rate for KaonLT Physics runs - Effs ~98-99% - Heep has an efficiency problem, but physics data does not - *NB* PeterB makes an excellent observation: - apparent rate in a selected region of SHMS focal plane in Heep is much higher than the average rate, because not the whole focal plane illuminated - suggests to put cuts on HMS to select narrow band of electrons - Dave: this is very hard to do in the standard analyzer - Peter: yes, you have to do it in a special analysis - started working on Heep singles analysis - checking w/ Junaid on analysis scripts and w/ Ali on replay scripts Next Meeting ------------- - Thur Sept 26 @ 16:30 Eastern/14:30 Regina - KaonLT will go first