JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

ALICE TRD

Transition Radiation Detector Overview and Status

Clemens AdlerPhysikalisches Institut Heidelberg

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Alice

TRD:Identification of electrons (p>1GeV) -0.9<η<0.9

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Operation principle

Small size Prototype measurement

Xe/CO2

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Some numbers

• 540 individual drift chambers

• 750 m² active area• 6 radial layers • 18 phi sectors

(“Supermodules”)• Full phi coverage• |eta|<0.9• 1.16 million

electronics channels

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Performance

• Pion rejection (90% electron efficiency)

• Position resolution

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Physics application

Fast simulationT. Mahmoud: Phd Thesis Heidelberg 2004

• Quarkonia:– J/Ψ, Y-> important probe of

QGP

TRD Trigger:• Triggering on High Pt

Electrons (t~6μs)• Input rate: few kHz

Output rate: <200 Hz

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Readout Chambers

• Challenges: – large area (1-1,7m²)

– low material budget (15% X0)

– high rigidity:

->Composite materials (e.g. ROPanel: FACC, Austria)

Large number of chambers:– Many production sites:

Dubna

GSI

Bucharest

Frankfurt

Heidelberg

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

CERN DG visit to Dubna

Chamber production in Dubna

• Lot of know how from Dubna (Hades experience) went into Chamber building procedures

• Important contribution to problem solving

• Very good communication

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

• X-ray test stand:To test gain uniformity of the ROCs

Joint development of Dubna (mechanical engineering) and Heidelberg (Controls)

Testing, QA

• Supermodule cosmic ray test stand in development at Dubna

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Production Status

• Chamber production started last year.– Heidelberg since 11/03– Dubna since 4/04– Bucharest since 10/04– GSI since 10/04– Frankfurt (summer

2005)

• 30 ROCs produced• 1st Supermodule to

be assembled in Summer

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

TRD in the ALICE Space frame

• ‚Supermodules‘ development: Joint effort of Dubna and Heidelberg

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Electronics

• Low power custom designed chips

• 4104 ROB x 17 MCM (Multi Chip Modules)

• MCM: - Analog PASA- ADC- TRAcklet Processor

(TRAP):Tracklet reconstruction in real time

• Status:– Final iterations on

ROB design to minimize noise

– TRAP+ADC Chip last iteration

– PASA full quantity in house.

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Testbeam 2004

• Testbeam with 6 Chamber Stack CERN, Oct. 2004

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Testbeam performance

• Data analysis ongoing: – Heidelberg – Frankfurt– GSI – Dubna (B. Batyunia

and S. Zaporozec)

• Final Electronics were working stable

• Chambers: Online plot:

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Dubna Contributions

• Readout Chambers

• Supermodule design

• Cosmic ray test stand

• X-ray test stand

• Software development, Simulation, Data analysis

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

Future Dubna TRD Activity

• Test beams: GSI June 2005• Chamber production (108 pc.): until End 2006• Software:

– Simulation – Test beam data analysis– Analysis software development

• Commissioning: – Cosmic ray test stand (Chamber alignment)– Supermodule assembly/testing– Supermodule installation at CERN starting 2006

JINR-BMBF Workshop, Dubna 18.01.2005 Clemens Adler PI Heidelberg

CollaborationMain Contributions:Germany:• Frankfurt University (IKF)• Gesellschaft für Schwerionenforschung (GSI) Darmstadt• Heidelberg University (Physikalisches Institut, Kirchhoff Institut)• Münster University (IKP)Russia:• JINR Dubna (Y.Zanevsky, Y.Panebratsev groups, S. Vodopianov)Romania:• NIPNE Bukarest (group of M.Petrovici)

Additional Subsystems:Japan: Tokyo University, Nagasaki UniversityGreece: Athens University Germany: FH Köln, University Kaiserslautern, FH Worms, TU Darmstadt