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HLab meeting Status report. T.Gogami 13/Sep/2011. 12 /Mar/2011 CNN News in D.C . Contents. CH 2 & H 2 O Λ issue ¼ σ Λ (CH 2 ) = σ Λ (H 2 O) Develop Tracking code. Experimental setup of JLab E05-115. p( e,e’K + )Λ,(Σ 0 ). Experimental setup of JLab E05-115. p( e,e’K + )Λ,(Σ 0 ). - PowerPoint PPT Presentation
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HLab meetingStatus report
T.Gogami13/Sep/2011
12/Mar/2011 CNN News in D.C.
Contents
• CH2 & H2O Λ issue– ¼ σΛ(CH2) = σΛ(H2O)– Develop Tracking code
Experimental setup of JLab E05-115p(e,e’K+)Λ,(Σ0)
Experimental setup of JLab E05-115
Splitter Magnet
HKS
HES e’
K+
p(e,e’K+)Λ,(Σ0)
Analysis process
trackingx , x’ , y , y’ at Reference plane
x’ , y’ , pat Target
Missing Mass
trackingx , x’ , y , y’ at Reference plane
x’ , y’ , pat Target
p : Λ , Σ0 ,12ΛB
Angle : Sieve slit
F2T functionF2T function
particle ID(select K+)
HKSHES
tune tune
~40 hours(5 shifts)
JLab E05-115p(e,e’K+)Λ,Σ0
Very preliminary
Multiplicity of typical layer of chamberHES HKS
~1.13
~1.28
~2.24
~4.94
Multiplicity is high for HKS
Hit wires in KDC1
Overhead viewKDC1
Black : hit wires Blue : selected wiresRed : track
Black : hit wires Blue : selected wiresRed : track
CH2 52Cr
Misidentification chance in hit wires selection increase !
REAL DATA REAL DATA
low high low high
Overhead view
Basic tracking procedure
Good TDC
Pattern recognition
Track fit
Solve left right
Select good combination
Black : hit wires Blue : selected wiresRed : track
CH2 target
KDC1
52Cr target
Combination selection with TOF counters
Reduce hit wire combinations (h_tof_pre.f)
High multiplicity
Real data
New tracking scheme
Good TDC
Pattern recognition
Track fit
Solve left right
Select good combination
Combination selection with TOF counters
Reduce hit wire combinations (h_tof_pre.f)
High multiplicity
• Hit wire selection with TOF• 1X & 2X • Grouping
• Pre-PID• Cherenkov detectors
Reduce hit wires to analyze
みそ
DC hit info. selection with TOF (xx’)
Selective region Maximum gradient
Minimum gradient
Particle direction
Gravity
CUT~8%
~17%
Procedure in “h_dc_tofcut.f”1. Get KTOF1X & 2X hit counter information2. Make combination of 1X and 2X hit counter if those two are in
same group (grouping) 3. Determine cut conditions on KDC1 & KDC24. Select Hit wires in KDC and Reorder them
CUT
Just applied to xx’-layers for test
Check works of the code
• GREEN regionSelective region
• RED markersSelected hit wires
• BLACK markersRejected hit wires
Seems to work well
Particle direction
Gravity
Results of TOF cut with grouping
CH2 , 2.0 [μA] , 76315
Shift
Same
Residual
Multiplicity
CH2 , 2.0 [μA] , 76315
σ 150 [μm] σ 150 [μm]
~2.3
~1.2
before after
x x’ x x’
Apply to u,v-layer
Applied to uu’ and vv’ layers , too.
Selective region determined by 1X and 2X
Convert
v v’-layer
x x’-layer
Check works of the code
• GREEN region Selective region• RED markers & lines Selected hit wires• BLACK markers & lines Rejected hit wires
v v’ u u’
x x’
v v’ u u’
x x’
KDC1 KDC2particle particle
Results of TOF cut with grouping (all layers)
Residual
Multiplicity
CH2 , 2.0 [μA] , 76315
σ 150 [μm] σ 150 [μm]
Multiplicity of uu’vv’-layers• CH2
• ~20% reduction• 52Cr
• ~5-10% reduction
Same
before after
Results of TOF cut with grouping (all layers)
Faster !
Increase !TOF cut works well
52Cr
CH2
52CrFaster !
Increase !
Parameters ?
DC hit info. selection with TOF
Selective region Maximum gradient
Minimum gradient
Particle direction
Gravity
CUT~8%
~17%
CUT
Stricter TDC cut
Results of Introduction new code
Increased !
Increased !
CH2
52Cr
Summary
• CH2 & H2O Λ issue– Improvement of tracking code
• ¼ σ(CH2) = σ(H2O)==> ½ σ(CH2) = σ(H2O)
– Virtual photon flux calc.– efficiency
End
Multiplicity improvement history
Multiplicity went down !• Analysis time
– 20% reduction for 52Cr• Number of Kaon (RUN:77124, 52Cr)
– 56 70 90 130
Applied TDC cut
DC TOF cut Matrix DC TOF cut ‘ (TDC cut)
Result of TOF cut with groupingOriginal code
With “h_dc_tofcut.f”Pure Selective regionallowance
allowance
KDC
Too strict
select
Optimal allowance
Good tracks hid by background appear ! Number of K+ ~2[%] up
Experimental setup of JLab E05-115
Position, angle
Position, angle
e’
K+
Experimental setup of JLab E05-115
Position, angle
Position, angle
e’
K+
Momentum vector
Experimental setup of JLab E05-115
Momentum vector
Missing Mass~40 hours(5 shifts)
JLab E05-115p(e,e’K+)Λ,Σ0
Very preliminary
KTOF TDC
• Cut10000 – 50000 (Current)18000 – 20500 (New)
Run 76314 for CH2 targetRun 77124 for 52Cr target
Data Summary
JLab E05-115 (2009/June – 2009/Nov)