CBM%20at%20FAIR

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CBM at FAIR

• Walter F.J. Müller, GSI
• 5th BMBF-JINR Workshop, 17-19 January 2005

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Outline

• Physics
• physics case
• observables
• Experiment
• requirements
• challenges

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States of strongly interacting matter
baryons hadrons partons

Compression heating quark-gluon
plasma (pion production)
Neutron stars
Early universe
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Phase diagram of strongly interacting matter
Freeze-out points calculated from measured
particle ratios using the statistical model
baryon density ?B ? 4 ( mT/2?h2c2)3/2 x
exp((?B-m)/T) - exp((-?B-m)/T) baryons
- antibaryons
Lattice QCD calculations Fedor Katz, Ejiri et
al.
dilute ?B ? 0.04 fm-3 ? 0.24 ?0
dense ?B ? 1.0 fm-3 ? 6.2 ?0
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Probing matter at high densities
Trajectories calculated by a 3-fluid
hydrodynamics modelToneev Ivanov
30 AGeV trajectory close to critical endpoint
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The future Facility for Antiproton an Ion
Research (FAIR)
SIS 100 Tm SIS 300 Tm U 35 AGeV p 90 GeV
Compressed Baryonic Matter
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Phase diagram of strongly interacting matter

• CERN-SPS, RHIC, LHC high temperature, low
  baryon density
• GSI SIS300 moderate
  temperature, high baryon density

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States of strongly interacting matter
Strangeness" of dense matter ? In-medium
properties of hadrons ? Compressibility of
nuclear matter? Deconfinement at high baryon
densities ?
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CBM Physics Topics and Observables

• In-medium modifications of hadrons
• ? onset of chiral symmetry restoration at high
  ?B ? measure ?, ?, ? ? ee-
  open charm (D mesons)
• Strangeness in matter
• ? enhanced strangeness production ? measure
  K, ?, ?, ?, ?
• Indications for deconfinement at high ?B
• ? anomalous charmonium suppression ? ?
  measure J/?, D
• Critical point
• ? event-by-event fluctuations
• Color superconductivity
• ? precursor effects ?

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Low-mass dileptons PbAu_at_40 AGeV
CERES Collaboration S.
Damjanovic and K. Filimonov, nucl-ex/0109017
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Meson production in central AuAu
W. Cassing, E. Bratkovskaya, A. Sibirtsev, Nucl.
Phys. A 691 (2001) 745
SIS18
SIS100/ 300
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Open Charm detection
Some hadronic decay modes D? (c? 317 ?m) D ?
K0? (2.9?0.26) D ? K-?? (9 ? 0.6) D0 (c?
124.4 ?m) D0 ? K-? (3.9 ? 0.09) D0 ? K-?
? ?- (7.6 ? 0.4)
D meson production in pN collisions
Measure displaced vertex with resolution of ?
30 µm !
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CBM Setup
? Radiation hard Silicon pixel/strip detectors in
a magnetic dipole field ? Electron detectors
RICH TRD ECAL pion suppression up to 105 ?
Hadron identification RPC, RICH ? Measurement
of photons, p0, ?, and muons ECAL
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CBM Technical Status Report
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CBM Collaboration 42 institutions, 14 countries
Croatia RBI, Zagreb Cyprus Nikosia Univ.
  Czech Republic Czech Acad. Science,
Rez Techn. Univ. Prague   France IReS
Strasbourg Germany Univ. Heidelberg, Phys.
Inst. Univ. HD, Kirchhoff Inst. Univ.
Frankfurt Univ. Kaiserslautern Univ. Mannheim
Univ. Marburg Univ. Münster FZ Rossendorf GSI
Darmstadt    
Russia CKBM, St. Petersburg IHEP Protvino INR
Troitzk ITEP Moscow KRI, St. Petersburg Kurchatov
Inst., Moscow LHE, JINR Dubna LPP, JINR
Dubna LIT, JINR Dubna LTP, JINR Dubna MEPhi,
Moskau Obninsk State Univ. PNPI Gatchina SINP,
Moscow State Univ. St. Petersburg Polytec.
U. Spain Santiago de Compostela Univ. Ukraine
Shevshenko Univ. , Kiev Univ. of Kharkov
Hungaria KFKI Budapest Eötvös Univ.
Budapest Korea Korea Univ. Seoul Pusan National
Univ. Norway Univ. Bergen Poland Krakow
Univ. Warsaw Univ. Silesia Univ.
Katowice   Portugal LIP Coimbra Romania NIPNE
Bucharest
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CBM ?????
From first page of CBM Collaboration List
4 Labs38 Persons
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Experimental Challenges
Central AuAu collision at 25 AGeV URQMD
GEANT4 160 p 360 ?- 330 ? 360 ?0 41
K 13 K-

• ? 107 AuAu reactions/sec
• (beam intensities up to 109 ions/sec, 1
  target)
• ? determination of (displaced) vertices with high
  resolution (? 30 ?m)
• ? identification of electrons and hadrons

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Pion misidentification
a)0
b)0.01
c)0.1
d)1
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Experimental Conditions
Hit rates for 107 minimum bias AuAu collisions
at 25 AGeV
Rates of gt 10 kHz/cm2 in large part of detectors
! ? main thrust of our detector design studies
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CBM DAQ Requirements Profile

• D and J/? signal drives the rate capability
  requirements
• D signal drives FEE and DAQ/Trigger requirements
• Problem similar to B detection, see BTeV, LHCb
• Adopted approach
• displaced vertex 'trigger' in first level, like
  in BTeV
• Additional Problem
• DC beam ? interactions at random times
• ? time stamps with ns precision needed
• ? explicit event association needed
• Current design for FEE and DAQ/Trigger
• Self-triggered FEE All hits shipped with time
  stamp
• Data-push architecture L1 trigger throughput
  limited but not latency limited

Substantial RD needed
Quitedifferentfrom theusualLHC
styleelectronics
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Conventional FEE-DAQ-Trigger Layout
Especially instrumented detectors
Detector
L0 Trigger
fbunch
Trigger Primitives
Dedicated connections
FEE
Cave
Limited capacity
Shack
L1 Accept
DAQ
Modest bandwidth
L2 Trigger
L1 Trigger
Limited L1 trigger latency
Specialized trigger hardware
Standard hardware
Archive
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The way out use Data Push Architecture
Detector
Self-triggered front-end Autonomous hit detection
fclock
FEE
No dedicated trigger connectivity All detectors
can contribute to L1
Cave
High bandwidth
Shack
DAQ
Large buffer depth available System is
throughput-limited and not latency-limited
Modular design Few multi-purpose rather many
special-purpose modules
FPGA andCPU mix
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Toward Multi-Purpose FEE Chain
preFilter
digital Filter
Hit Finder
Backend Driver
PreAmp
ADC

• Si Strip
• Pad
• GEM's
• PMT
• APD's

Anti-AliasingFilter
Sample rate 10-100 MHz Dyn. range 8...gt12 bit
'Shaping' 1/t Tailcancellation Baselinerestorer
Hit parameter estimators Amplitude Time
Clustering Buffering Link protocol
All potentially in one mixed-signal chip
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CBM DAQ and Online Event Selection
Data flow 1 TB/sec
1st levelselection 1 Pops
Data flow 1 GB/sec
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CBM RD working packages
FEE, DAQ, Online Event Selection, Computing
Feasibility studies Simulations
Design construction of detectors
?,?, ? ?ee- Univ. Krakow JINR-LHE Dubna
Framework GSI
Silicon Pixel IReS Strasbourg Frankfurt
Univ., GSI Darmstadt, RBI Zagreb, Univ. Krakow
MWPC TRD JINR-LHE, Dubna GSI Darmstadt, Univ.
Münster NIPNE Bucharest
Tracking KIP Univ. Heidelberg Univ.
Mannheim JINR-LHE Dubna JINR-LIT Dubna
J/? ? ee- INR Moscow GSI
KIP Univ. Heidelberg Univ. Mannheim GSI
Darmstadt JINR-LIT, Dubna Univ. Bergen KFKI
Budapest Silesia Univ. Katowice Warsaw Univ.
Straw TRD JINR-LPP, Dubna FZ Rossendorf FZ
Jülich Tech. Univ. Warsaw
Silicon Strip Moscow State Univ CKBM St.
Petersburg KRI St. Petersburg Univ. Obninsk
J/? ? µµ- PNPi St. Petersburg SPU St. Petersburg
Ring finder JINR-LIT, Dubna
ECAL ITEP Moscow GSI Darmstadt Univ. Krakow
RPC-TOF LIP Coimbra, Univ. Santiago Univ.
Heidelberg, GSI Darmstadt, Warsaw Univ. NIPNE
Bucharest INR Moscow FZ Rossendorf IHEP
Protvino ITEP Moscow RBI Zagreb Univ. Marburg
p, K, p ID Heidelberg Univ, Warsaw Univ. Kiev
Univ. NIPNE Bucharest INR Moscow
D ? Kp(p) GSI Darmstadt, Czech Acad. Sci.,
Rez Techn. Univ. Prague
RICH IHEP Protvino GSI Darmstadt
Theory JINR-LTP, Dubna
?, ?,O PNPi St. Petersburg SPU St. Petersburg
Magnet JINR-LHE, Dubna GSI Darmstadt
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CBM Event Reconstruction Analysis

• Track finding
• Hough transform
• Cellular automaton
• Conformal mapping
• 3D track following
• Track fitting
• Kalman filter
• Kalman filter (projections)
• Parabolic approximation
• Polynomial approximation
• Orthogonal polynomial set
• Primary vertex fitting
• Minimization of impact parameters
• Geometrical Kalman filter
• Secondary vertex fitting
• Geometrical Kalman filter
• Mass and topological constrained fit
• RICH ring finding
• Track extrapolation

LHE LIT LIT LHE LIT LIT LHE LIT LIT LI
T
LHE LHE

• Analysis
• .......
• ?-Analysis
• low-mass dileptons
• .......

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CBM Magnet Design (LHE)
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CBM Fast Detectors (LHE)
Joint test beamat GSI in July '04
2 chambers from Dubna
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CBM Straw based TRD (LPP)
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Experimental program of CBM
Observables Penetrating probes ?, ?, ?, J/?
(vector mesons) Strangeness K, ?, ?, ?, ?,
Open charm Do, D? Hadrons ( p, p), exotica
Detector requirements Large geometrical
acceptance good hadron and electron
identification excellent vertex resolution high
rate capability of detectors, FEE and DAQ
Systematic investigations AA collisions from 8
to 45 (35) AGeV, Z/A0.5 (0.4) pA collisions
from 8 to 90 GeV pp collisions from 8 to 90
GeV Beam energies up to 8 AGeV HADES
? ? ee- ?
Large integrated luminosity High beam intensity
and duty cycle, Available for several month per
year
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Stay tuned for Part II by Prof. A. Malakhov
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