BTeV Muon Trigger
14
M. Selen, DOE Visit, 2003 BTeV Muon Trigger BTeV Muon Trigger Mats Selen Aug 25, 2003 • Algorithm: Overview Efficiency & Rejection • Timing: Results of running DSP based trigger code on a large sample of Monte Carlo events. • R&D: What's Next.
description
BTeV Muon Trigger. Mats Selen Aug 25, 2003. Algorithm: Overview Efficiency & Rejection Timing: Results of running DSP based trigger code on a large sample of Monte Carlo events. R&D: What's Next. R. U. V. S. Muon system has 3 stations with 4 views each (R,U,V,S). - PowerPoint PPT Presentation
Transcript of BTeV Muon Trigger
M. Selen, DOE Visit, 2003
BTeV Muon TriggerBTeV Muon TriggerMats Selen Aug 25, 2003
• Algorithm: Overview Efficiency & Rejection
• Timing: Results of running DSP based trigger code on
a large sample of Monte Carlo events.
• R&D: What's Next.
M. Selen, DOE Visit, 2003
Muon system has 3 stations with 4 views each (R,U,V,S)
Muon system has 3 stations with 4 views each (R,U,V,S)
R U V S
M. Selen, DOE Visit, 2003
R0
R1
R2
In each octant: For a given view (R,U,V, or S): Examine correlations between hit tubes in all 3 stations
How to triggeron muon tracks:
M. Selen, DOE Visit, 2003
R1R0
R2
R2
R0
R1
• muon tracks• uds events
Muon tracks line on a simple plane:R2 = 27.69 1.26*R0 + 2.20*R1
(R0,R1,R2) in raw “tube numbers”
Distance-To-Plane Cut
Strategy: Cut on closest distance to this plane for each crossing/octant/view.Strategy: Cut on closest distance to this plane for each crossing/octant/view.
Distance to “plane”
=1.5 tubes good events
M. Selen, DOE Visit, 2003
0 100 200 300
R0
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R2
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R0
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R0
R2
• • Determining
track chargeis simple !
R2 = 1.275*R0 -125R0
R2
All we need to do is look at R2 vs R0.
M. Selen, DOE Visit, 2003
50 100 150 200 250 300 350 400
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Crude kinematicmeasurements
are also possible:
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R0
R2
R0
R2
Ptotal
Sin2
• Not exploited further in this study.
• Can (for example) imagine calculating a crude dimuon mass.
M. Selen, DOE Visit, 2003
Look for tracks by octant.Look for tracks in one or more views (R,U,V or S).Tag each octant as NO, POS or NEGA “dimuon” event has at least one POS and one NEG octant
Di-Muon Trigger:Di-Muon Trigger:
M. Selen, DOE Visit, 2003
Example Trigger Study
Example Trigger Study
Conditions for these plots:- Use all 384 tubes/view (also studied using only the outermost 352, 320 tubes)
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D-Cut
Eff
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ncy
2/4 views (e=100%)
3/4 views (e=100%)
2/4 views (e=97%)
3/4 views (e=97%)
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D-Cut
Eff
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2/4 views (e=100%)
3/4 views (e=100%)
2/4 views (e=97%)
3/4 views (e=97%)
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0 0.5 1 1.5 2D-Cut
Rej
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2/4 views (e=100%)
3/4 views (e=100%)
2/4 views (e=97%)
3/4 views (e=97%)
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0 0.5 1 1.5 2D-Cut
Rej
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2/4 views (e=100%)
3/4 views (e=100%)
2/4 views (e=97%)
3/4 views (e=97%)
“2/4” and “3/4” means that 2 and 3 planes respectively, out of the possible 4, were needed to pass “D-Cut” toidentify a track in an octant.
M. Selen, DOE Visit, 2003
Dimuon Trigger Efficiency vs. Tube Hit Efficiency(this example is for Cut = 1)
Dimuon Trigger Efficiency vs. Tube Hit Efficiency(this example is for Cut = 1)
There is a large parameter space that yields > 60% and Rej > 500
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0.90 0.92 0.94 0.96 0.98 1.00
Tube Hit Efficiency
Eff
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2/4 (384)
2/4 (352)
2/4 (320)
3/4 (384)
3/4 (352)
3/4 (320)0.00
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0.90 0.92 0.94 0.96 0.98 1.00
Tube Hit Efficiency
Eff
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ncy
2/4 (384)
2/4 (352)
2/4 (320)
3/4 (384)
3/4 (352)
3/4 (320)
D-cut = 1
<N> = 2
M. Selen, DOE Visit, 2003
Performance vs. <N>(average number of
min-bias events/crossing)
Performance vs. <N>(average number of
min-bias events/crossing)
Even for <N> = 5 we can get a rejection of ~ 500 with an efficiency of ~ 60%.
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Eff
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<N>=2 (384)
<N>=2 (352)<N>=2 (320)
<N>=3 (384)<N>=3 (352)
<N>=3 (320)<N>=4 (384)
<N>=4 (352)
<N>=4 (320)<N>=5 (384)
<N>=5 (352)<N>=5 (320)0.00
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Eff
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<N>=2 (384)
<N>=2 (352)<N>=2 (320)
<N>=3 (384)<N>=3 (352)
<N>=3 (320)<N>=4 (384)
<N>=4 (352)
<N>=4 (320)<N>=5 (384)
<N>=5 (352)<N>=5 (320)
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Rej
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<N>=2 (384)
<N>=2 (352)
<N>=2 (320)
<N>=3 (384)
<N>=3 (352)
<N>=3 (320)
<N>=4 (384)
<N>=4 (352)
<N>=4 (320)
<N>=5 (384)
<N>=5 (352)
<N>=5 (320)0
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0 0.5 1 1.5 2D -Cut
Rej
ecti
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<N>=2 (384)
<N>=2 (352)
<N>=2 (320)
<N>=3 (384)
<N>=3 (352)
<N>=3 (320)
<N>=4 (384)
<N>=4 (352)
<N>=4 (320)
<N>=5 (384)
<N>=5 (352)
<N>=5 (320)
“3/4”, e = 97%
M. Selen, DOE Visit, 2003
Size & SpeedSize & SpeedSize & SpeedSize & Speed• Work done by UIUC ECE grad student John Cassel:
Ported RTES file-I/O code to the muon trigger. Implement “clock-cycle” counting technique for timing tests. Re-wrote & optimized PC code for DSP (i.e. made it run fast !!fast !! ) DSP results for efficiency & rejection agree with PC!
TMS320C6711
M. Selen, DOE Visit, 2003
<Time> = 760 ticks(~6 s @ 133 MHz)
<Time> = 760 ticks(~6 s @ 133 MHz)
<Time> = 1686 ticks(~13 ms @ 133 MHz)
<Time> = 1686 ticks(~13 ms @ 133 MHz)
Unless something changes,speed is not an issue.
Unless something changes,speed is not an issue.
Executable Code:91.3 kBytes
Executable Code:91.3 kBytes
M. Selen, DOE Visit, 2003
Muon Trigger StatusMuon Trigger Status
• Work to date is a “existence proof”. Trigger algorithm in good shape. Speed adequate.
• System will evolve as design continues
M. Selen, DOE Visit, 2003
BTeV FutureBTeV Future
You tell us!
