Nov 21/24 PionLT/KaonLT Analysis Meeting Notes ---------------------------------------------- (Notes by GH) Today: PionLT will be discussed first Present ------- Regina - Garth Huber, Alicia Postuma, Nathan Heinrich, Muhammad Junaid, Ali Usman, Nacer Hamdi Virginia - Richard Trotta CUA - Tanja Horn FIU - Pete Markowitz Ohio - Julie Roche JLab - Dave Gaskell Nathan ------ - no report, preparing for tomorrow's committee meeting Junaid ------ PionLT tracking updates - updated geometry parameter files (better drift chamber position data), improves residuals - Mark's tracking algorithm changes - implemented new parameter values to turn on Mark's algorithm changes - using his default parameter values for now - Heep replays using the new algorithm - 5.986 GeV and 10.56 GeV Coin - change to W distribution is subtle, tail to left of elastic peak has a bit steeper slope (log scale), fewer slightly fewer events - 10.56 Exp/MC ratio changed from 1.006 to 1.010, more events passing cuts so ratio went up - however, the Exp yield was calculated with the old tracking efficiency - *NB* new tracking efficiencies using the new algorithm need to be used - that will probably result in the ratio getting closer to 1.0 - updated HMS matrix elements for 6.7, 5.9, 6.1 GeV/c - NPS group is still working on 5.6 GeV/c matrix elements - some discussion about hdelta_offset hphi_offset values to use - *NB* need to use the same values used for matrix element fits - this means that for momenta with "old" matrix elements, offset values of zero should be used, while for "NPS" matrix elements, non-zero offset values that they used need to be retained - *NB* i.e. two different sets of parameter files are needed, please be careful thiese are implemented correctly - Ali: do we need to use the same offsets in SIMC? - Dave: SIMC uses its own matrix elements, reconstruction matrix is not changed in SIMC, do not apply the matrix element offsets to SIMC Nacer ----- KaonLT Heep singles - submitted jobs to reanalyze w/Mark's tracking chagnes, but iFarm slow - investigated a tighter W-cut for HMS, SHMS singles - high tail cut ~1.05 - moved lower cut from 0.8 to 0.9 to see what happens - 8.2 GeV: left tail data extend all the way to W=0 - 10.6 GeV: W peak is wider, 0.9 cut is clearly too tight, obtain Exp/MC ratio R=0.75(!) - *NB* need to use W cut that results in less sensitivity, GH suggests a cut near the change in slope of left background for each beam energy Richard ------- - having problems with iFarm cache being read-only - Julie: can only write to cache from batch now - Nathan: for interactive login, there is a command to specifically put a file on cache - will look up the documentation and add to RedMine notes Trying KaonLT iterations w/ new TT functional form - reduced chi-square now <1.5 - having an issue with MM_K spectra - lambda peaks not lined up correctly with expected mass, different shifts for high and low epsilon - shift is less for 10.6 GeV Q2=3.0, W=2.32 setting, which was done right after Heep (where beam energy offset was determined), other 10.6 GeV settings have a larger shift - Ali, Alicia saw some ~MeV shifts in their pi+ analyses that had to be corrected *NB* should cross compare what offsets are needed for all 3 analyses, to see if they're consistent - GH: *NB* you should write a script to fit just the top part of the MM peak for each run, and line it up to SIMC peak location on run-by-run basis Alicia ------ - PRL manuscript still with reviewers Geant4 proton absorption correction - read in focal plane variables for an actual data sample - store hit position and time in each hodoscope - implementing thicknesses from spreadsheet - hodoscope (x,y) will be limiting dimension for all materials except the aerogel - Dave: is it obvious what physics list to use, we're interested in hadronic interactions? - will start with StandardPhysics list Ali --- - no update, working on thesis Next Meeting ------------- - Thur Dec 5 @ 16:00 Eastern/15:00 Regina - *NOTE* no meeting next week due to US Thanksgiving holiday - KaonLT will go first