Dec 21/23 PionLT/KaonLT Analysis Meeting Notes ---------------------------------------------- (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 ------- Regina - Garth Huber, Ali Usman, Muhammad Junaid, Nathan Heinrich, Vijay Kumar, Nacer Hamdi JLab - Dave Gaskell FIU - Pete Markowitz CUA - Richard Trotta, Tanja Horn Richard ------- Weight iteration script for LT-separations - working on script to fit separated cross sections to get parameters for next iteration, other parts done Heep analysis - made a nice table of efficiencies and associated uncertainties for Heep and Physics data analysis - HGC cuts to select K+ after discussion with Peter Bosted: - place a cut around HGC hole to reduce pi+ leakthrough - *NOTE* will need to place SAME CUT on SIMC - place a NPE<1 cut to eliminate pions - DG: the cut can be fairly tight since K+ are below HGC Cherenkov threshold, there will be NPE from knock-on electrons, but it shouldn't make too much difference whether the cut is at 1 or 2 NPE - *NOTE* will need to find the correction factor (a few %) for the K+ with knock-on electrons that are removed by this cut - Calorimeter Efficiencies per spectrometer setting, not beam energy - DG: need a dedicated study to determine these efficiencies, not from the report files - AU: this study was done earlier. Looked at Heep singles data w/low pi- contamination - some Heep settings had P_HMS above Cherenkov threshold, and could not be used - DG: the efficiency should plateau for momenta > ~3 GeV/c, it would be okay to extrapolate this number to higher momenta above the Cherenkov threshold, the issue is the efficiency at very low HMS momenta - DG: need a fit or lookup table for efficiency vs P_HMS - Heep Data/MC yield ratios - when removing HGC cut on Heep analysis, W shifted by ~0.1 MeV, this affects data/MC yield comparison - Yield ratios have a linear trend vs. Q2 that needs more investigation - no error bars are plotted yet - suggest to have simple PID cuts for Heep COIN since so clean, try to make the analysis as robust as possible - Vijay has a much flatter yield ratio plot, so the difference needs to be understood - GH+TH: Vijay and Richard should communicate by email on exactly what cuts and efficiencies are applied to the Heep data, so the major parts of their analyses can be compared - LH2 boiling correction - discussion about the calculated uncertainties and how they should vary with current, RT gets a surprisingly large increase in uncertainty with current - Eqn 5.22a,b on Boiling Correction in Carlos Yero's thesis - TH: Carlos' eqn is absolute error in the boiling correction, you can't apply this formula without modification for percentage error Ali --- piDelta BSA - looking into rho decay contribution, running SIMC - working on script to combine L,C,R SHMS settings - next will look at higher Q2 settings, and rerun SIMC w/ offsets Dave ---- Looking into MM resolution issues - Run 4920, Q2=2.115, P_HMS=5.292 GeV/c - HMS-delta vs MM: see a clear linear correlation - HMS-delta vs xptar,yptar: also see some correlation (more complicated with some curvature) - clearly indicates some optics issues that can account for the wider MM peak compared to SIMC - AU: the KaonLT replay used a dedicated set of Matrix Elements for P_HMS=6.5 GeV/c, but nothing special for 5.3 GeV/c - next step is to look at MM vs Focal Plane variables, to see if there is a linear correlation that can be removed with an ad-hoc correction Vijay ----- Low Q2 lumi and Heep analysis - Carbon-12 HMS, Heep yields vs current - found a small bug in the script used to produce last week's plots - in addition, was previously using statistical error in EDTM study, now using 2% uncertainty in EDTM livetime from Carlos Yero's thesis - the issue is that in KaonLT, the EDTM could only be set manually from the electronics room. For many runs we did not have enough EDTM events, and it was difficult to monitor this during the data taking. Heep Data/MC yield ratios - plot has a small linear dependence with Q2, but error bars at high Q2 are fairly large - DG: surprised the error bar is so large at Q2=3.75 - the run sheets show 3x40k events for this setting - Vijay will confirm what was done, possibly only 1 run was analyzed instead of all three Nacer ----- Drift Chamber calibration checks after new Hodo calibs - still debugging DC calib scripts, trying to adapt PionLT code to KaonLT - discussing with Junaid Nathan ------ Coincidence Reference times - finished on Monday, CoinTime now centered at zero and sharper for all runs - changes pushed to GitHub Full replay script - working w/ Junaid on the script and checking Junaid ------ - merged all Nathan's changes to GitHub - everything is set up, but problems on including Helicity variables in replay - Ali can point to which script to use - All Events No EDTM for all runs except Lumi, which will be All Events - hope to submit full replays soon, and will monitor them over holidays After the replay is done: - Junaid will work on Tracking Efficiencies - Nathan will work on Lumi - will start with scaler and UnTracked yields analysis which are independent of Junaid's work - depending on Junaid's progress, will pivot to PID analysis if tracking effs not ready when needed for Tracked Lumi analysis Next Meeting ------------ - Thur Jan 4 @ 15:00 Eastern/14:00 Regina - PionLT will go first Hoping everyone has a good holiday. Merry Christmas and Happy New Year!