Jun 27/24 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 - Muhammad Junaid, Ali Usman, Alicia Postuma, Nathan Heinrich, Vijay Kumar, Zach Sullivan, Garth Huber JLab - Dave Gaskell Ohio - Julie Roche York - Stephen Kay CUA - Tanja Horn FIU - Pete Markowitz UVA - Richard Trotta Junaid ------ PionLT Offsets - tested OOP offsets w/ opposite sign and rechecked Heep distributions, got worse for all energies - all offset signs now finalized - comparison of Data & MC distributions with offsets applied - delta, xptar, yptar, etc. for both spectrometers - overlap of distribution shapes looks pretty good - preliminary Heep Coin Data/MC yield ratios - EffCharge = Tracking, DetEff, Hodo-3/4, EDTM corrections applied, LH2 boiling corr from Richard's analysis (8%/100uA, so ~4% correction) - *NB* some inconsistencies in MC to Data normalization seen from plot-to-plot, so plotting scripts need to be re-checked - *NB* need to check that W-cut is applied consistently to both Data and MC Next steps: - planning to do Pass-2 replays - data were not replayed yet w/offsets, also need to include new BCM calibs Nathan & Zach ------------- PionLT Lumi Studies - applied uncertainty in current based on BCM calib in terms of unc in slope and offset - *NB* still need to talk to Dave Mack re errors from BCM saturation, will look through DocDB if don't hear from DM within a week - Rel Yield vs Current/Rate w/ BCM errors applied - Carbon runs 16727-16737 - scaler yields have larger (more reasonable) errors now - *NB* BCM offset clearly needs some optimation, but things generally flat - preliminary LH2 boiling study - LH2 seees about 4% boiling @ 80uA - will combine settings for a combined fit - *NB* Procedure to combine settings (from GH): - First do a fit of each setting study and normalize to unity at zero rate/current - Then overlay all of the normalized studies, and check for consistency - If consistent within errors, do a combined fit Next steps: - look at some 2021 Lumi studies, w/ PreScale correction - Look at Coin Lumi settings Richard ------- KaonLT LTsep fitting - Q2=5.5, Center Setting only, MMk cut and pion subtraction applied - fitting sigL=(p1+p2*log(Q2))exp(p3*|t|) and sigT=(p4*|t|/Q2-1)*exp(p6*|t|) - result of 1st iteration: Data/MC ratio ~0.7 @ -t=0.465, ~0.5 @ 0.590 - did 31 iterations, but ratios did not change, something wrong - GH: *NB* it's really important that the fit for new model parameters converges, otherwise you can't consider it as an iteration - this appears to be the reason why the ratios did not improve - meeting coming up w/ Vijay, Ali to discuss proton absorption correction, and rad on/off systematic studies Alicia ------ Overview of latest updates to BSA paper after comments from this group - got rid of 2 planes figure to save some space - for the Q2-xB plot, can move symbol legend from caption to inside the figure to save some space - *NB* GH can do this after he gets home - will circulate the manuscript to all co-authors later today - comments will be due July 16, the day after Alicia's presentation at Hall A/C workshop Ali --- HMS Cherenkov efficiencies - to recall, the KaonLT efficiency (~97%) is noticeably lower than in PionLT, what is the reason for this? - looked up HMS Cherenkov efficiency study in Bircu's thesis, p.115 - plotted CerEff and pion Rejection Factor for different NPE cut - had a similar Efficiency to Ali's KaonLT study, ~2-3% inefficiency - Looked up hclog where the light leak was fixed: https://logbooks.jlab.org/entry/3854383 Oct 7/2020 entry by Chuck Mahlong - believe the light leak started when broken mirror was fixed in early 2018, before KaonLT started - this means all of KaonLT and summer 2019 PionLT data have the light leak inefficiency - conclusion: we understand the reason why the KaonLT and PionLT inefficiencies are so much different and hence can assign a smaller systematic uncertainty Vijay ----- Summer 2019 PionLT systematic uncertainty studies - added variations in LT, TT for RadCor on/off and MM cuts to spreadsheet - *NB* LT, TT got larger for RadCor on/off, so we have to consider whether to assign a 1-sided uncertainty, similar to what Alicia needed to do for BSA - relative uncertainties show, better would be to tabulate the absolute uncertainties per t-bin Next steps: - looking at acceptance cut systematic uncertainty - applying +/-10% cut variation, same as in Tanja's thesis Next Meeting ------------- * NOTE* we do not meet next week due to July 1 (Canada) and July 4 (USA) holidays - Next meet: Thur July 11 @ 15:00 Eastern/13:00 Regina - KaonLT will go first