upsilon cross section - purdue universityjones105/talks/meier_upsilon_aug... · 2015. 8. 10. ·...
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8/7/2015 1/29 Michael Meier, Purdue University
Upsilon Cross Section
Michael Meier, Matthew Jones
Purdue University
CDF Collaboration
August 7, 2015
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8/7/2015 2/29 Michael Meier, Purdue University
Upsilon Cross Section
• NΥ(nS) is the Υ(nS) signal yield in the fitted peak
• A is the geometric detector acceptance depending on valid region of detector
• ε is the reconstruction efficiency with selection cuts for fiducial muons
• ∫ L dt is the integrated luminosity
ypdtLA
NnSBr
dydp
d
T
nS
T
)(2
))((
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8/7/2015 3/29 Michael Meier, Purdue University
Acceptance • Measured with Monte Carlo in bins of pT and run
period ▪ Function of time because of dead wires,
chambers, etc.
• Ratio of Number accepted to Total Number Generated
• Number Accepted – CMUP-CMU or CMUP-CMX ▪ Rapidity |y| < 0.6 ▪ Decay vertex |z| < 60 cm ▪ One muon fiducial in CMU and CMP with pT > 4 ▪ One muon fiducial in CMU or CMX with pT > 3 ▪ Valid region of detector – depends on CMU, CMP, CMX
• Total Number Generated ▪ Rapidity |y| < 0.6
Gen Total
Accepted
N
NA
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8/7/2015 4/29 Michael Meier, Purdue University
Valid Detector Regions
• CMU
▪ Veto 1/3 of 8W and east end of 6E
• CMP
▪ Remove dead wires as a function of run number
• CMX
▪ Skip wedges 15 and 20
▪ Hole for soleniod cryo (side 1, wedges 5 and 6)
▪ Miniskirts (wedges 15 to 20) missing before Run 227704
▪ Keystone wedges (side 0, wedges 5 and 6) missing before Run 233112
▪ Small hole on the west (side 0, wedge 14) between Run 190695 and Run 210009
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8/7/2015 5/29 Michael Meier, Purdue University
Upsilon Trigger • UPSILON_CMUP_CMU(_DPS)
▪ L1_TWO_CMU1.5_LUMI_280 » 2 muon stubs in CMU with pt > 1.5 GeV/c » 2 XFT tracks with pt > 1.52 GeV/c
▪ L2_CMUP1.5_PT3_CMU1.5_PT1.5DPS » 1 CMUP muon with pt > 3.04 GeV/c » 1 CMU muon with pt > 1.52 GeV/c
▪ L3_UPSILON_CMUP3_CMU1.5 » 1 CMUP muon with pt > 3.0 GeV/c, Δx(CMU) 1.5 GeV/c » 1 XFT track with pt > 1.52 GeV/c, 1 XFT track with pt > 2.04 GeV/c, signal in CSX
▪ L2_CMUP1.5_PT3_CSX1.5_PT2_CSX_DPS » 1 CMUP muon with pt > 3.04 GeV/c » 1 CMX muon with pt > 2.04 GeV/c
▪ L3_UPSILON_CMUP3_CMX2 » 1 CMUP muon with pt > 3.0 GeV/c, Δx(CMU)
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8/7/2015 6/29 Michael Meier, Purdue University
Selection Cuts • Muon cuts
▪ CDF Muon Object, |Δz0(mu1,mu2)| < 5.0 cm, opposite charge (mu1,mu2), Δphi(mu1,mu2) > 2.25 degrees, |z0| < 60.0 cm
• CMUP–CMU ▪ CMUP muon matched to XFT track
pT > 4.05 GeV, Δx(CMU)
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8/7/2015 7/29 Michael Meier, Purdue University
Efficiency
• Efficiency is measured with the Muon+SVT sample (jbmu)
• B_SEMI_CMUP4_TRACK2_D120 ▪ L1_CMUP6_PT4_NCLC64
» 1 muon stub in CMU with pt > 6.0 GeV/c
» 1 XFT track with pt > 4.09 GeV/c
▪ L2_CMUP6_PT4_D0_&_TRK2_D120_DPHI90_DPS » 1 XFT track with pt > 4.09 GeV/c and 1 CMUP muon
» 1 SVT track with pt > 2 GeV/c, SVT chi2
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8/7/2015 8/29 Michael Meier, Purdue University
Trigger Efficiency • JPsi candidates from all tracks in Muon+SVT sample
▪ |Δz0(mu1,mu2)| < 5.0 cm, opposite charge (mu1,mu2), Δphi(mu1,mu2) > 2.25 degrees
▪ Both tracks |z0| < 60.0 cm, XFT matched, XFT fiducial
• Require 1 CMUP muon with pt > 4.0 GeV/c, has CMUP L1 trigger, is fiducial in CMUP ▪ If both muon candidates pass these cuts, then consider the one with higher
pt as the CMUP muon
• Require other track to be fiducial in CMU, pass CMU acceptance (be in a valid region of detector), and have pt > 3.0 GeV/c ▪ Check for hits in CMU (CdfMuon) and Δx(CMU)
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8/7/2015 9/29 Michael Meier, Purdue University
CMU Efficiency
• Required ▪ fiducial in CMU ▪ pass CMU
acceptance ▪ pt > 3.0 GeV/c
• Passed Cuts ▪ has CMU hits
(CDFMuon object) ▪ Δx(CMU)
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8/7/2015 10/29 Michael Meier, Purdue University
CMUP Efficiency • Required
▪ fiducial in CMU & CMP
▪ pass CMU and CMP acceptance
▪ pt > 3.0 GeV/c
• Passed Cuts ▪ has CMUP hits
(CDFMuon object) ▪ Δx(CMU)
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8/7/2015 11/29 Michael Meier, Purdue University
CMX Efficiency • Required
▪ fiducial in CMX ▪ pass CMX
acceptance ▪ pt > 3.0 GeV/c
• Passed Cuts ▪ has CMX hits
(CDFMuon object) ▪ Δx(CMX)
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8/7/2015 12/29 Michael Meier, Purdue University
Trigger Efficiency Plots
• Trigger Efficiency is CMUP efficiency times CMU(CMX) efficiency
• CMUP-CMU (top plot)
• CMUP-CMX (bottom plot)
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8/7/2015 13/29 Michael Meier, Purdue University
XFT Efficiency and Vertex Efficiency
• XFT Efficiency
▪ Measured using unbiased sample tracks from the kaon in B± → J/ψ K± decays reconstructed with jpmm dataset
• Vertex Efficiency
▪ Measured using minimum bias events up to run 203799
• Not yet included in cross section calculations!
0039.09648.0XFT
0035.09550.0 vertex
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8/7/2015 14/29 Michael Meier, Purdue University
• Previous measurement with 29 run periods instead of 28 ▪ first 5 run periods cover different run numbers
• Measured using JPSI_CMUP4_CMU_L2_DPS and JPSI_CMUP4_CMX_L2_DPS ▪ Requires 4 GeV/c CMUP muon in Level 2 and JPsi in Level 3
• Require unbiased leg to be CMUP and pt > 4.0 GeV/c • Satisfies Level 2 if has
XFT track and muon stub in CMU or CMX within range of cells from CMU or CMX look-up tables
• Efficiency calculated from yield of JPsi passing and failing Level 2 requirements
Level 2 Efficiency (Previous Measurement)
CMU+CMU (black) CMU+CMX (red)
Not yet included in cross section calculations!
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8/7/2015 15/29 Michael Meier, Purdue University
Upsilon Sample
• Upsilon candidates in jbmm data sample ▪ |Δz0(mu1,mu2)| < 5.0 cm, opposite charge (mu1,mu2),
Δphi(mu1,mu2) > 2.25 degrees ▪ Both muons |z0| < 60.0 cm, XFT matched, XFT fiducial ▪ One muon with pt>4.05 GeV/c, other muon with pt>3.05 GeV/c
• CMUP-CMU ▪ CMUP muon with pt > 4.0 GeV/c, fiducial in CMUP, pass CMU
and CMP acceptance, Δx(CMU)
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8/7/2015 16/29 Michael Meier, Purdue University
Upsilon Mass Plots • Plots of upsilon mass in
bins of pt and run period for CMUP-CMU and CMUP-CMX
• Yields found in each bin of pt and run period
• 28 run periods • 8 pt bins
▪ 0 to 2 GeV/c ▪ 2 to 4 GeV/c ▪ 4 to 6 GeV/c ▪ 6 to 8 GeV/c ▪ 8 to 12 GeV/c ▪ 12 to 17 GeV/c ▪ 17 to 23 GeV/c ▪ 23 to 40 GeV/c
CMUP-CMU Run Period 10
0 < pt < 2 GeV/c
CMUP-CMU Run Period 10
2 < pt < 4 GeV/c
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8/7/2015 17/29 Michael Meier, Purdue University
Calculations • Cross Section as a function of run period
▪ Sum yield over acceptance for all pt bins
▪ Divide by luminosity in that run period
• Cross Section as function of pt bin ▪ Sum yield over acceptance and efficiency for all run
periods
▪ Divide by total luminosity in all run periods
binspt periodrun bin,pt
periodrun bin,pt
periodrun periodrun
1)periodrun (
A
N
yL
periodrun periodrun periodrun bin,pt
periodrun bin,pt
total
1)binpt (
A
N
pyL T
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8/7/2015 18/29 Michael Meier, Purdue University
Upsilon “Cross Section” (run period)
• Yield/lum for each run period (for all pt bins)
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8/7/2015 19/29 Michael Meier, Purdue University
Upsilon “Cross Section” (run period)
• Shows time dependence for cross section
Average: 55.38 ± 0.13 χ2 = 1146.27 χ2 = 171.34
Average: 30.37 ± 0.09 χ2 = 830.65 χ2 = 498.90
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8/7/2015 20/29 Michael Meier, Purdue University
Upsilon Cross Section (run period) • Yield/(lum*eff*acc) for each run period (sum over all pt bins)
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8/7/2015 21/29 Michael Meier, Purdue University
Upsilon Cross Section (run period)
• Reduced time dependence for CMUP-CMU
Average: 638.43 ± 4.2 χ2 = 107.48 χ2 = 55.71
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8/7/2015 22/29 Michael Meier, Purdue University
Upsilon Cross Section (run period)
• CMUP-CMX time dependence needs more analysis
Average: 697.56 ± 7.0 χ2 = 97.42 χ2 = 59.17
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8/7/2015 23/29 Michael Meier, Purdue University
Previous Measurements
• Current Work for |y|< 0.6
▪ CMUP-CMU = 638.43 ± 4.2 pb
▪ CMUP-CMX = 697.56 ± 7.0 pb
• D0 Run II (1.96 TeV) for |y|< 0.6
▪ PRL 94, 232001 (2005): 732 ± 19(stat) ± 73(syst) ± 48 (lumi) pb
▪ PRL 100, 049902 (2008): 628 ± 16(stat) ± 63(syst) ± 38 (lumi) pb
• CDF Run I (1.8 TeV) for |y| < 0.4
▪ PRL 88, 161802 (2002): 680 ± 15(stat) ± 18(syst) ± 26 (lumi) pb
▪ PRL 75, 4358 (1995): 753 ± 29(stat) ± 72(syst) pb
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8/7/2015 24/29 Michael Meier, Purdue University
Upsilon Cross Section (pt) – No Level 2 Eff • Yield/(lum*eff*acc*Δy*Δpt) for each pt bin (for all run periods)
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8/7/2015 25/29 Michael Meier, Purdue University
Upsilon Cross Section (pt) – No Level 2 Eff • Log scale for Yield/(lum*eff*acc*Δy*Δpt)
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8/7/2015 26/29 Michael Meier, Purdue University
Future Work
• Reduced time dependence for CMUP_CMU
• CMUP_CMX still shows slight time dependence
▪ Look into CMX muons and phi dependence
• Include Level 2 efficiency
▪ Not yet included in cross section calculations!
CMU+CMU (black) CMU+CMX (red)
Level 2 Efficiency
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8/7/2015 27/29 Michael Meier, Purdue University
Backup Slides
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8/7/2015 28/29 Michael Meier, Purdue University
CMP Dead Wires • JPsi signal reconstructed in the Muon+SVT sample (jbmu) • Monte Carlo sample of muons used to map occupancy of CMP
chambers ▪ CMP occupancy depends on chamber number, due to different
material in front of the various regions of the detector
• Assume ratio of number of counts in a given CMP chamber to total number of counts in the CMP system is the same in data and Monte Carlo
• Expected number of counts (Nexpected) in a CMP chamber (i) in a run given by:
• Must have 100 counts (mu) in a CMP chamber ▪ Runs are combined to have the expected number of counts in a
chamber
• Measure the actual number counts (Nactual) in the same set of runs
• Compute the Poisson probability to count Nactual given Nexpected • Consider the CMP chamber (wire) dead for probability < 1%
totalData
totalMC
iMC
,i NN
NN ,
,
,
expected
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8/7/2015 29/29 Michael Meier, Purdue University
Plot of CMP Dead Wires
• Dead CMP wire number vs Run Index (run number) • Only bins with probability < 1% are filled
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