Nov 2/23 PionLT/KaonLT Analysis Meeting Notes --------------------------------------------- (Notes by GH & AH) 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 - Nathan Heinrich, Ali Usman, Garth Huber, Vijay Kumar, Nacer Hamdi, Alicia Postuma, Muhammad Junaid York - Stephen Kay CUA - Richard Trotta, Tanja Horn FIU - Pete Markowitz Stephen ------- Update on the NPS experiment data taking - Shared some of the challenges the Hall C team had during the current data collection - Mentioned Problems with the DAQ system - unlike PionLT, lots of DAQ reconfigurations in a cyclic order - Target Operator will be very busy because of the DAQ issues - They were also facing spectrometer magnet issues, where response time delay is observed - Junaid has not yet received his US visa. If it is not issued by Nov 20, he will need to cancel his shifts, so others have time to fill them Richard ------- Checking effect of Heep offsets received from Garth - GH provided offsets for different energy sets - Richard tried using global offsets for all 5 KaonLT beam energies - The offsets work for low energy, but need to be different at high energy - observe a progressive shift in EM distribution with beam energy, other variables are more stable - Richard tried ad-hoc adjusting SHMS momentum offset to fix this - for dpp -1.0000: The W looks good, but the E_miss is worse for high energies - for dpp -8.0000: the inverse happens for E_miss - Need to investigate the E_miss sensitivity to the offsets - Garth suggests instead to try the offsets for just the 3 highest beam energies - Tanja: it seems that it will not be possible to find a set of offsets that work for all data, will need at least 2 sets - Garth thinks 3 sets of offsets are needed: - Summer 2019 low beam energy offsets (Vijay's data) - 3 highest KaonLT beam energies (Richard and Ali's data) - 2 lowest KaonLT beam energies (Nacer's data) - had a sign issue last week compared to Vijay, this is corrected now - Out of Plane offsets - tried applying Garth's PMY offset, did not shift PMY very much - RT just realized had wrong sign on SHMS offset - Garth: Check the instruction for the correct implementation of the computed offsets - Vijay: maybe worth comparing the OOP offset between data, rather then MC vs. data - Garth will make a plot with PMY data only (not data-SIMC), maybe it results in a slightly larger OOP offset Vijay ----- No update, just completed Chapter 2 of thesis - Will check the effect of the computed OOP offsets for his data as well - Lumi analysis will be next after OOP offset Ali --- Beta cut efficiency studies - Looking at Heep coin data (cleaner data), to study Beta cut efficiency, due to Coin time issues for 10.6 GeV data. - still looking at cut-dependence - with original cuts, got ~95% for COIN events at 10.6 GeV, but ~98% for 6.2, 8.2 GeV data - want to understand how the cut-dependence particularly affects the low epsilon data - Showed CoinTime vs Beta SHMS: See a tail at high Beta without PID cut - 6.2 GeV: no boomerang, but long tail up to beta=1.8 (Heep data) - maybe try only a beta lower limit cut, no upper limit cut - Tanja: agrees can put PID cuts to study beta-efficiency - need a CLEAN SAMPLE, then while identifying these events, adjust the cut - try different PID cuts to clean the sample to a level were they become not sensitive to the cuts Alicia ------ Draft slides on 10.6 GeV CT issue for the Quarterly Analysis meeting - Discussion on the observed CoinTime issues at 10.6 GeV. - Garth still has to put together his slides on Offset studies Nathan ------ Checking if Coin time reference time cuts make sense, as suggested in his committee meeting - Tcoin.pTRIG1_ROC1_tdcTime vs CTime.ePiCoinTime_ROC1 and same vs ROC2 - TDC time TRIG1 and TRIG4 were used to compute reference time - get various multiple-pea histos and diagonal correlations, very difficult to understand - will make a quick script to look at a wide range of Run# - Tried different cuts and replayed to see the effects - Goal is to pick a peak in RawTDC distribution and place appropriate cut values in cutfile - checking if cuts are correct on: pTRIG1,4_ROC1,2 - do not yet know what the cut on hT2 is for Junaid ------ Continuation of Hodoscope calibration - the gap noticed on the 2D plots in Beta vs Delta is removed after turning off the HGC cut - Moving to drift chamber calibration Nacer ----- Working on Kaon LT data @ 3.8 GeV - After noticing some quantities offsets (Beta SHMS) from their expected values, a new replay was submitted - maybe the last replay was not done with the final calibrations? Next Meeting ------------ - Thur Nov 9 @ 15:00 Eastern/14:00 Regina - PionLT will go first - Please send and post the notes from last week's meeting