Upload
kineta
View
43
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Track Fitting and Comparator Results. Emu meeting @ UC Davis Feb. 26, 2005 Yangheng Zheng University of California, Los Angeles. Motivation & Introduction Results. Motivations. Check output from comparator chips (for both ME2/2 and ME1/1) - PowerPoint PPT Presentation
Citation preview
Track Fitting and Comparator Track Fitting and Comparator ResultsResults
Emu meeting @ UC DavisFeb. 26, 2005
Yangheng ZhengUniversity of California, Los Angeles
Motivation & Introduction
Results
02/26/2005Emu meeting @ UC Davis2
MotivationsMotivations
Check output from comparator chips (for both ME2/2 and ME1/1)
Get familiar with Stan’s track-fitting utility package (TrackFnd)
Test the unpacking software (ORCA/EmuDAQ) for test-beam 2004 data
Look at ME1/1 data from TB2004
02/26/2005Emu meeting @ UC Davis3
Stan’s Track Fitting FrameworkStan’s Track Fitting Framework
Pedestal Subtraction Precision Sampling Time buckeye shaping Cross Talk is a function of ts (capacitative+slightly
resistive coupling between adjacent strips) lookup table
Cathode Noise Correlation unfired events Fitting Gatti distribution hit position / each layer Track Finding Kalman Filter Track Fitting A straight line least squares fit Details can be found:
http://www.physics.ohio-state.edu/~durkin/testbeam03/TrackFnd.htm
02/26/2005Emu meeting @ UC Davis4
Data for Gatti FittingData for Gatti Fitting
)50()50()50(
)0()0()0(
)50()50()50(
RML
RML
RML
qqq
qqq
qqq
stripsti
me
bin
s
Largest pedestal subtracted ADC value
INPUT DATA:
OUTPUT: track hit position for each layer through the least squares fitting
02/26/2005Emu meeting @ UC Davis5
Something NewSomething New New interface between TrackFnd and
ORCA/EmuDAQ Add options of gMinuit for fitting
distributions of buckeye and Gatti Change pedestal subtraction method New constants for ME11
cross talk cathode noise correlation Gatti parameters strip width and no staggering
02/26/2005Emu meeting @ UC Davis6
Buckeye ShapingBuckeye Shaping
4tc
cs ttts ett /)(4)(
02/26/2005Emu meeting @ UC Davis7
Peaking Time Peaking Time ttccME22 (tc33.25ns)
ME11(tc28ns)
ME11: smaller gas gap and wire spacing shorter drifting time
02/26/2005Emu meeting @ UC Davis8
Peak Charge Time BinsPeak Charge Time Bins
ME22 (TB2003) ME22 (TB2004) ME11 (TB2004)
02/26/2005Emu meeting @ UC Davis9
Pedestal SubtractionPedestal Subtraction
Standard method: subtracting first two time samples
Method 2: pedestals empty event (lookup table for every strip)
Method 3: pedestals fitting all available time samples for every event (buckeye shape + constant pedestal)
02/26/2005Emu meeting @ UC Davis10
Pedestal Subtraction (cont.)Pedestal Subtraction (cont.)
Method 1 – Method 2 Method 3 – Method 2ME22 (TB2004)
Mean 1.041
RMS 3.17
Mean 4.322
RMS 5.901
02/26/2005Emu meeting @ UC Davis11
Pedestal Subtraction (cont.)Pedestal Subtraction (cont.)
ME22 (TB2004)
---- Method 1
---- Method 2
---- Method 3
02/26/2005Emu meeting @ UC Davis12
Cross Talk Cross Talk a function of ts
determined by tracks passed within 0.05 strip width of the center of the strip
ME22(TB2003)
ME22(TB2004)
ME11(TB2004)
small statistics
ts (ns)
cro
ss t
alk
frac
tio
n
02/26/2005Emu meeting @ UC Davis13
Cathode Noise CorrelationCathode Noise Correlation Determined from unfired strips For time bins i and j,
For time bins 3, 4, 5, 6 (ADC counts)
For ME22, TB2003 and TB2004 show similar results ME11 shows different noise correlation No correlations between adjacent strips’ time bins (<1
count)
a
jja
iiajiij qqqqCC ))((
2.123.62.46.4
3.64.129.69.4
2.49.60.148.8
6.49.48.84.16
9.93.52.32.4
3.57.101.60.4
2.31.67.115.7
2.40.45.71.14
2.79.35.20.3
9.37.70.49.2
5.20.45.79.3
0.39.29.37.7ME22 (TB2003) ME22 (TB2004) ME11 (TB2004)
02/26/2005Emu meeting @ UC Davis14
Gatti ParametersGatti Parameters
half gas gap (h parameter) configuration: ME22 4.75mm, ME11 3.00mm fitting: ME22 4.91mm, ME11 2.99mm
strip width ME22 8.5-16.0mm, ME11 3.15-7.6mm
number of wire group per layer ME22 64, ME11 48
strip staggering ME22 0.5 strip, ME11 no staggering
02/26/2005Emu meeting @ UC Davis15
2 2 of Gatti Fittingof Gatti Fitting
)()( 1
,
2 xqqxqq expj
measjij
strips ji
expi
measi V
measj
measiijij qqsyserrCV
NDOF: 9 - 3 - 1 = 5
ME22 (TB2004) ME11 (TB2004)
Investigating the large tail effect
0.08 for ME22=
2 2
En
trie
s
En
trie
s
Mean 4.99
RMS 3.16
Mean 4.999
RMS 3.16
02/26/2005Emu meeting @ UC Davis16
Event DisplaysEvent DisplaysME22 (TB2004) ME11 (TB2004)
02/26/2005Emu meeting @ UC Davis17
Residue (3Residue (3rdrd Layer) Layer)
ME22 (TB2004) ME11 (TB2004)
sigma=0.0178 sigma=0.0177
3rd layer removed from track fitting
02/26/2005Emu meeting @ UC Davis18
Comparator Ouput ResolutionComparator Ouput Resolution
fitted track position - comparator output
02/26/2005Emu meeting @ UC Davis19
Left Half Hits vs Right Half HitsLeft Half Hits vs Right Half Hits
wrong output due to the ambiguous charge difference (see next slide)
02/26/2005Emu meeting @ UC Davis20
Output ProbabilityOutput Probability
wrong assignment due to the ambiguous charge difference
02/26/2005Emu meeting @ UC Davis21
Output EfficiencyOutput Efficiency
correct comparator output
correct strip# output
comparator output residue within ¾ strip
02/26/2005Emu meeting @ UC Davis22
SummarySummary Unpacking software seems robust Small changes applied to TrackFnd class For ME22, results of track fitting of
TB2003 can be fully reproduced. For ME11, the large tail effect of 22 and
systematic errors are under investigation Comparator chip produced reasonable
results for both ME11 and ME22
02/26/2005Emu meeting @ UC Davis23
NextNext
need to understand ME11 data better more refinements can be done
gain effect cross talk as a function of chamber
position geometry constants