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Updates of DISC Software

Mustafa Schmidt, Simon Bodenschatz, Michael Duren, ErikEtzelmuller, Klaus Fohl, Avetik Hayrapetyan, Oliver Merle,

Julian Rieke

September 13, 2016

Mustafa Schmidt Updates of DISC Software 0 / 18

1/18

Full Simulation Chain

PndDisc()

${PANDAROOT}/disc/ ${PANDAROOT}/pnddata/DiscData/

Simulation

PndDiscTaskDigitization()

Digitization

PndDiscTaskReconstruction()Reconstruction

PndDiscTaskPID()PID

PndDiscParticleMCPoint()Information about charged particles

PndDiscSensorMCPoint()Information about sensor hits

PndDiscDigitizedHit()Sensor information (pixel number, TDC time etc.)

PndDiscReconResult()Theoretical hit pattern

PndDiscCherenkovResult()Reconstructed Cherenkov Angle

PndDiscPID()Log(Likelihood) values for π, K, p

PhotoSensor()Sensor Description

Mustafa Schmidt Updates of DISC Software 1 / 18

2/18

Simulation Output

PndDiscSensorMCPoint()Photon Hit Position:fX, fY, fZPhoton Entering Position:photon entering pos (fX, fY,fZ)Photon Hit Momentum:fPx, fPy, fPzPhoton EnteringMomentum:photon entering mom (fX,fY, fZ)Reflection Angle:internal reflecting angle

PndDiscParticleMCPoint()Particle Incoming Position:fX, fY, fZParticle Outgoing Position:pos out (fX, fY, fZ)Particle IncomingMomentum:fPx, fPy, fPzParticle OutgoingMomentum:mom out (fX, fY, fZ)PDG Code: pdgCodeParticle Charge: chargeParticle Mass: mass

Mustafa Schmidt Updates of DISC Software 2 / 18

3/18

Digitization, Reconstruction, PID Output

PndDiscTaskDigitization()Detector ID:detector idReadout ID: readout idSensor ID:sensor idPixel Number: pixel numberPixel Position: pixel positionTDC Time: tdc time

PndDiscReconResult()Sensor ID: sensorPixe ID: pixelTime: timeHypothesis: hypothesis

PndDiscCherenkovResult()Cherenkov angle:cherenkov angle

PndDiscPID()Likelihood π: loglikepionLikelihood K : loglikekaonLikelihood p: loglikeproton

Mustafa Schmidt Updates of DISC Software 3 / 18

4/18

Adding Event Display

Mustafa Schmidt Updates of DISC Software 4 / 18

5/18

Fixed Problems

Problem in ROOT::Math::Interpolation::kLINEAR →PDE inside digitization could not be used until nowLibrary libMathMore added to the dependencies inCMakeLists.txt

Other Problems:DEPENDENCIES was written wrong in CMakeLists.txt

[nm]λ300 400 500 600 700

#Eff

icie

ncy

[%

]

0

5

10

15

20

25

MCP Efficiency

Mustafa Schmidt Updates of DISC Software 5 / 18

6/18

Changes in Track Reconstruction

Possibility to use Monte-Carlo tracks or reconstructed trackswith GenFit:

PndDiscTaskReconstruction :: UseTrueTracks(kTRUE/kFALSE )

Getting position and momentum information with:TClonesArray *tclarr_track (TClonesArray*)

io_manager->GetObject("SttMvdGemGenTrack");PndTrack *track = (PndTrack*)tclarr_track->At(i);FairTrackParP par = track->GetParamLast();

Calculating position on radiator disk assuming straight line:(xDiscyDisc

)= zTrack − zDisc

pz·(

pxpy

)

Mustafa Schmidt Updates of DISC Software 6 / 18

7/18

Resolution Studies for GenFitSpatial and momentum resolution of Protons with p = 4 GeV/cand θ = 15◦

Resolution [cm]0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2

Ent

ries

0

10

20

30

40

50

60

70

80

90

Directions

x

y

Spatial Resolution of PANDA Tracking System at Disc DIRC

Resolution [mrad]0.01− 0.008− 0.006− 0.004− 0.002− 0 0.002 0.004 0.006 0.008 0.01

Ent

ries

0

20

40

60

80

100

Polar Angle Resolution

Resolution [GeV/c]1− 0.8− 0.6− 0.4− 0.2− 0 0.2 0.4 0.6 0.8 1

Ent

ries

0

20

40

60

80

100

120

Momentum Resolution of PANDA Tracking System

Mustafa Schmidt Updates of DISC Software 7 / 18

8/18

Adding Calibration Script

Script added for calibration of Focusing Elements usingMonte-Carlo hits with random ϕ angles:

Pixel #0 20 40 60 80 100

[rad

]ϕ

0.35

0.4

0.45

0.5

0.55

0.6

0.65

0.7

Data Points

Linear Fit

MC FEL Calibration

Values are used for the hit pattern calculation

Mustafa Schmidt Updates of DISC Software 8 / 18

9/18

Cherenkov Angle Reconstruction

Input Parametersxp , yp , θp , φp , tp

Hit PatternnFEL, z, t

Mass Hypothesesmπ , mK , mp

Cherenkov Angleθc

Time Cutθ′

c

Photon Propagationsph , tph

Removed Unphysical Anglesθ′′

c

Hypothesis Cutθ′′′

c ; |θ′′c − θc,theo | < θcthresh

Average Cherenkov Angleθc = 1

N

∑θ′′′

c

Theoretical Cherenkov Angleθc,theo

Mustafa Schmidt Updates of DISC Software 9 / 18

10/18

Reconstructed Chernekov Angle

Particle momentum p = 3 GeV/c, polar angle θ = 15◦

[rad]cθ0.7 0.72 0.74 0.76 0.78 0.8 0.82 0.84 0.86 0.88 0.9

Ent

ries

0

10

20

30

40

50 Primary Particle

Pion

Kaon

Proton

Cherenkov Angle Distribution

Mustafa Schmidt Updates of DISC Software 10 / 18

11/18

Hitpattern Matching

Input Parametersxp , yp , θp , φp , tp

Mass Hypothesesmπ , mK , mp

Hit PatternnFEL, z, t

Theoretical HitpatternnFEL,theo , ztheo

Photon Propagationsph , tph

Spatial Cut|z − ztheo | < zthresh

Time Cut|t − ttheo | < tthresh

Likelihood Value

Mustafa Schmidt Updates of DISC Software 11 / 18

12/18

Reconstruction Results

Hit pattern matching for particle momentum p = 3 GeV and polarangle θ = 15◦:

Sensor ID0 5 10 15 20 25 30

Pixe

l Num

ber

0

10

20

30

40

50

60

70

80

90

100

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

Simulated Hitpattern

Sensor ID5 10 15 20 25 30 35

Pixe

l Num

ber

0

10

20

30

40

50

60

70

80

90

100

Predicted Hitpattern

PionKaonProton

Used bandpass filter 360–465 nm including PDE

Mustafa Schmidt Updates of DISC Software 12 / 18

13/18

Particle Identification

Momentum p = 4 GeV/c, polar angle θ = 15◦

))-log(L(K))πlog(L(60− 40− 20− 0 20 40 60

Eve

nts

0

10

20

30

40

50

60

70

80

90

Separation Power: 2.64618

Primary Particles

Pions

Kaons

Gaussian Fit

Likelihood Distribution

Mustafa Schmidt Updates of DISC Software 13 / 18

14/18

Conclusion & Outlook

PID in principle working in PandaRoot (results not sufficientuntil now)Cleaning of unnecesary codeBetter implementation of code into PandaRoot frameworkImprovement of reconstruction algorithmTesting PID with specific benchmark channel

Mustafa Schmidt Updates of DISC Software 14 / 18

15/18

Thank you very much foryour attention!

Mustafa Schmidt Updates of DISC Software 15 / 18

16/18

Backup Slides

Mustafa Schmidt Updates of DISC Software 16 / 18

17/18

Theoretical Model

Angle Definitions:

particle

φrel

αFEL

Radiator Disk

FEL

Particle

θc ϕ

tanϕ′ = tanϕcosαFEL

ϕ′

Mustafa Schmidt Updates of DISC Software 17 / 18

18/18

Theoretical Model

Calculation of the Cherenkov angle:

θc = arccos(sin θp cosφrel cosϕ+ cos θp sinϕ) (1)

θp: θ angle of particleφrel : angular difference between φ angle of particle and photonϕ: Angle between total reflected photon and radiator disksurface

Calculation of ϕ if θc is known:

cosϕ = A cos θcB ±

√cos2 θp − cos2 θc

B +(A cos θc

B

)(2)

with A = sin θp cosφrel and B = A2 + cos2 θp

Mustafa Schmidt Updates of DISC Software 18 / 18