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TPC R&D in CanadaTPC R&D in CanadaDean Karlen / University of Victoria & TRIUMFDean Karlen / University of Victoria & TRIUMF
Canadian LC-TPC Group:Canadian LC-TPC Group: Carleton University:Carleton University: Robert Carnegie, Madhu Dixit, Hans Mes, Robert Carnegie, Madhu Dixit, Hans Mes, Kirsten Sachs Kirsten Sachs University of Montreal:University of Montreal: Jean-Pierre Martin Jean-Pierre Martin University of Victoria:University of Victoria: D.K., Paul Poffenberger, Gabe Rosenbaum D.K., Paul Poffenberger, Gabe Rosenbaum
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 22
OutlineOutline
Focus of the Canadian LC-TPC R&D programFocus of the Canadian LC-TPC R&D program
Updates:Updates: On the eastern front: TPC1On the eastern front: TPC1
finalizing analysis of P10 and ArCO2 cosmic data from 2002finalizing analysis of P10 and ArCO2 cosmic data from 2002 investigation of resistive foil for induction signalsinvestigation of resistive foil for induction signals
On the western front: TPC2On the western front: TPC2 first results from cosmic data in magnetic field (June 2003)first results from cosmic data in magnetic field (June 2003) comparison with Monte Carlo simulationcomparison with Monte Carlo simulation
Plans...Plans...
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 33
Focus of Canadian TPC R&DFocus of Canadian TPC R&D
Investigate the design of the end plate for the Investigate the design of the end plate for the TPC to achieve its objectives:TPC to achieve its objectives: micropattern gas avalanche detectormicropattern gas avalanche detector modest size pads: ~2 mm modest size pads: ~2 mm ~6 mm pads ~6 mm pads ~100 micron resolution per pad row in the transverse ~100 micron resolution per pad row in the transverse
directiondirection good two particle separation powergood two particle separation power
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 44
Endplate designEndplate design
Significant effort to study the performance of Significant effort to study the performance of GEM devices with rectangular readout padsGEM devices with rectangular readout pads cosmics used to measure resolution propertiescosmics used to measure resolution properties
TPC 1AFall 2001
TPC 1BSummer 2002
TPC 2Summer 2003
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 55
Cosmic ray trackingCosmic ray tracking
The traditional approach:The traditional approach: examine data from eachexamine data from each
row separately: define a row separately: define a point along the trackpoint along the track
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 66
Cosmic ray trackingCosmic ray tracking
The traditional approach:The traditional approach: examine data from eachexamine data from each
row separately: define a row separately: define a point along the trackpoint along the track
find best track that goesfind best track that goesthrough pointsthrough points
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 77
Cosmic ray trackingCosmic ray tracking
The traditional approach:The traditional approach: examine data from eachexamine data from each
row separately: define a row separately: define a point along the trackpoint along the track
find best track that goesfind best track that goesthrough pointsthrough points
measure resolution by themeasure resolution by thescatter of the dots from thescatter of the dots from thetracktrack
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 88
Cosmic ray trackingCosmic ray tracking
Problem with the Problem with the traditional approach:traditional approach: information in one rowinformation in one row
is not sufficient to defineis not sufficient to definea point along the track:a point along the track: charge sharing depends oncharge sharing depends on
x coordinatex coordinate azimuthal angleazimuthal angle width of charge cloudwidth of charge cloud
dependence is non-lineardependence is non-linear linear centroid findinglinear centroid finding
degrades resolutiondegrades resolution
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 99
Cosmic ray trackingCosmic ray tracking
Our whole track approach:Our whole track approach: combine information fromcombine information from
all rows to determine theall rows to determine thetrack parameters:track parameters: x coordinatex coordinate azimuthal angleazimuthal angle width of charge cloudwidth of charge cloud
the concept of a point on the concept of a point on the track is non-existentthe track is non-existent
x resolution for a singlex resolution for a singlerow is measured byrow is measured byperforming two track fits performing two track fits
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1010
Cosmic ray trackingCosmic ray tracking
The sharing of charge byThe sharing of charge byneighbouring pads is a simple neighbouring pads is a simple enough concept to develop a enough concept to develop a first principles model forfirst principles model formaximum likelihood maximum likelihood
Benefits of the whole trackBenefits of the whole trackapproach:approach: no empirical parametersno empirical parameters
less calibrationless calibration
reasonable estimates forreasonable estimates forerror matrixerror matrix
better resolutionbetter resolution
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1111
News from the Eastern FrontNews from the Eastern Front
Finalizing analysis of data from TPC-1bFinalizing analysis of data from TPC-1b F analysis code developedF analysis code developed
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1212
Transverse resolutionTransverse resolution
100 100 m resolutionm resolutionachieved with 2 mmachieved with 2 mmpads… furtherpads… furtherimprovements expectedimprovements expected
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1313
Resistive anode studiesResistive anode studies
To spread signals over larger area, a resistive To spread signals over larger area, a resistive film can be used:film can be used:
Especially importantEspecially importantfor Micromegas…for Micromegas…
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1414
Resistive anode studiesResistive anode studies
Early results look promisingEarly results look promising
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1515
News from the Western FrontNews from the Western Front
Progress since Arlington:Progress since Arlington: New TPC (TPC2) commissioned in VictoriaNew TPC (TPC2) commissioned in Victoria Cross compiler for STAR electronics developed to Cross compiler for STAR electronics developed to
build more efficient DAQ systembuild more efficient DAQ system Cosmic tracking indicated field distortionsCosmic tracking indicated field distortions TPC redesign fixed the distortionsTPC redesign fixed the distortions TPC brought to TRIUMF for magnetic field testsTPC brought to TRIUMF for magnetic field tests Track fitter extended for curved tracksTrack fitter extended for curved tracks Begin using JAS3 for automated analysisBegin using JAS3 for automated analysis Analysis of the magnetic field runsAnalysis of the magnetic field runs
code is publicly available via anonymous CVS accesscode is publicly available via anonymous CVS access
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1616
Victoria groupVictoria group
Graduate student:Graduate student: Gabe RosenbaumGabe Rosenbaum
RA (part-time):RA (part-time): Paul PoffenbergerPaul Poffenberger
Summer students:Summer students: Camille Belanger-ChampagneCamille Belanger-Champagne Brie HoffmanBrie Hoffman
Technical support: (many)Technical support: (many) D.K.D.K.
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1717
TPC2 commissionedTPC2 commissioned
Constructed at Carleton University, operated at Constructed at Carleton University, operated at the University of Victoria with cosmic telescopethe University of Victoria with cosmic telescope
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1818
Data acquisitionData acquisition
Cross compiler built (Paul)Cross compiler built (Paul) can compile applications for STAR electronics on can compile applications for STAR electronics on
Linux, and load onto VxWorks platformLinux, and load onto VxWorks platform see see www.linearcollider.cawww.linearcollider.ca for information for information
New data acquisition program (Paul/Gabe)New data acquisition program (Paul/Gabe) data runs written to single filedata runs written to single file
contains header information for run/eventcontains header information for run/event
only channels connected to FEE cards writtenonly channels connected to FEE cards written ~10% deadtime loss for cosmics~10% deadtime loss for cosmics
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 1919
Tracking with 6 STAR FEE cardsTracking with 6 STAR FEE cards
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2020
Tracking distortions foundTracking distortions found
Residual from track depends on track location:Residual from track depends on track location:
x coordinate (mm)
mea
n re
sidu
al f
or c
entr
e ro
w (
mm
)
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2121
TPC modificationTPC modification
End of drift volume had a wire mesh to terminate End of drift volume had a wire mesh to terminate cylindrical volume just in front of square GEMs: cylindrical volume just in front of square GEMs: source of field distortions?source of field distortions?
wire mesh
drift volume
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2222
TPC modificationTPC modification
New endpiece constructed:New endpiece constructed: 70 70 m wire strung with 2.5 mm spacingm wire strung with 2.5 mm spacing
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2323
Tracking distortions fixedTracking distortions fixed
With new end piece, problem is solvedWith new end piece, problem is solved
x coordinate (mm)
mea
n re
sidu
al f
or c
entr
e ro
w (
mm
)
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2424
Analysis codeAnalysis code
Track fitting now with curvatureTrack fitting now with curvature
data taken with no mesh:large field distortions!
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2525
Setup at TRIUMFSetup at TRIUMF
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2626
Example events at ~25 cm driftExample events at ~25 cm drift
0 Tesla 0.45 Tesla 0.9 Tesla
= 2.3 mm = 1.2 mm = 0.8 mm
Gas: P10
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2727
Diffusion measurementsDiffusion measurements
Transverse diffusion significantly reduced at Transverse diffusion significantly reduced at high B fieldshigh B fields
B = 0
B = 0.45 T
B = 0.9 T
3cm 30 cm
B (T)B (T) D D ((m/m/cm)cm)(Data)(Data)
D D ((m/m/cm)cm)(MC)(MC)
0.0. 498498 541541
0.450.45 221221 221221
0.90.9 134134 137137
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2828
Track resolutionTrack resolution
Fit track to all but one rowFit track to all but one row fix fix 00, 1/, 1/rr, and , and ,,
fit to one rowfit to one rowalonealone
compare compare xx00
from the two fitsfrom the two fits fit to Gaussianfit to Gaussian
3cm 30 cm
TDR spec.goal
B = 0
B = 0.45 T
B = 0.9 T
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 2929
Resolution dependenciesResolution dependencies
No large dependencies No large dependencies on threshold or gainon threshold or gain
Track angle effect visibleTrack angle effect visible~ 2 primary
~ 1 primary
~ 5000
~ 2500
0 < < 0.05
0.05 < < 0.1
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 3030
Comparison with MC simulationComparison with MC simulation
GoodGoodagreementagreement
MC truth info MC truth info confirms thatconfirms thatprocedure toprocedure tomeasure resolutionmeasure resolutionis sensibleis sensible
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 3131
Induction signals visibleInduction signals visible
Pads next to those collecting electrons see Pads next to those collecting electrons see induced pulses (also seen in our x-ray test cell)induced pulses (also seen in our x-ray test cell)
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 3232
Magnetic field distortionsMagnetic field distortions
Field not completely uniform within drift volume:Field not completely uniform within drift volume: cause ionization tracks to rotate in azimuthcause ionization tracks to rotate in azimuth
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 3333
Magnetic field distortionsMagnetic field distortions
To check, use cosmic telescope to define a To check, use cosmic telescope to define a standard beamstandard beamof cosmicsof cosmics mean mean angle angle
changes inchanges inthe directionthe directionexpectedexpected
2003 ALCPG Cornell Meeting: 13/7/032003 ALCPG Cornell Meeting: 13/7/03 TPC R&D in Canada / D. Karlen / UVic & TRIUMFTPC R&D in Canada / D. Karlen / UVic & TRIUMF 3434
Plans for TPC2Plans for TPC2
With the successful TRIUMF magnet tests, we With the successful TRIUMF magnet tests, we will take the TPC to DESY for tests in their will take the TPC to DESY for tests in their superconducting magnet (up to 5 Tesla)superconducting magnet (up to 5 Tesla) starts next week!starts next week!