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Strangeness and Charm in the CBM Experiment. V. Friese Gesellschaft f ür Schwerionenforschung Darmstadt, Germany v.friese@gsi.de. for the CBM collaboration. The QCD Phase Diagram and SIS 300. Beam energy 10 – 45 AGeV: highest baryon densities first order phase transition
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Strangeness and Charm in the CBM Experiment V. Friese Gesellschaft für Schwerionenforschung Darmstadt, Germany v.friese@gsi.de for the CBM collaboration
The QCD Phase Diagram and SIS 300 • Beam energy 10 – 45 AGeV: • highest baryon densities • first order phase transition • critical point ?
Baryon & Energy Densities @ SIS 300 C. Fuchs, E. Bratkovskaya, W. Cassing Large energy and baryon densities accessible ε > εcrit for large part of system evolution Similar results from QGSM
Trajectories in the Phase Diagram 3-Fluid Hydro calculation with hadron gas EOS (Ivanov, Russkikh, Toneev, nucl-th/0503088) Early phase not equilibrated Predicts reaching the phase boundary for 10 AGeV 30 AGeV trajectory near critical point
Trajectories in the Phase Diagram (2) UrQMD transport (hadrons, strings, reonances)Stöcker, nucl-th/0506013 Qualitativ agreement with 3-Fluid-Hydro Phase border in reach, maybe critical point also
Anomaly in relative strangeness Gazdzicki, Gorenstein, Act. Phys. Polon. B 30 (1999) 2705 Plateau in pt slopes Something's going on at low energies K/π fluctuations exceed UrQMD v2 underpredicted by UrQMD from 30 AGeV on
CBM: Physics Topics & Observables Equation-of-state at high B collective flow of hadrons, particle production at threshold energies (open charm) Deconfined phase at high B Strangeness production K, , , , Charmonium suppression ? Charmonium (J/ψ, ψ'), open charm (D0, D) Chiral symmetry restoration at high B In-medium modifications of hadrons , , e+e- , open charm, ..... 1. order phase transition & its critical endpoint Event-by-event fluctuations (K/π, pT, ...)
CBM: Experimental Programme Systematic investigations: A+A collisions from 8 to 45 (35) AGeV, Z/A=0.5 (0.4) p+A collisions from 8 to 90 GeV p+p collisions from 8 to 90 GeV Beam energies up to 8 AGeV: HADES High rates, rare probes Detector requirements Large geometrical acceptance (azimuthal symmetry !) good hadron and electron identification excellent vertex resolution high rate capability of detectors, FEE and DAQ Large integrated luminosity: High beam intensity and duty cycle, Available for several month per year
The FAIR Facility existing GSI facilities • Primary beams: • 1012/s; 1.5-2 GeV/u; 238U28+ • 4x1013/s 90 GeV protons • 1010/s 238U 35 GeV/u ( Ni 45 GeV/u) SIS 100/300 CBM • Secondary beams: • rare isotopes 1.5 - 2 GeV/u; • factor 10 000 increased intensity • antiprotons 3(0) - 30 GeV • Storage and cooler rings • e – A Collider • rare isotopes • 1011 stored and cooled antiprotons • 0.8 - 14.5 GeV • Relativistic heavy-ion physics • Hadron physics with antiproton beam • Plasma physics with pulsed beams • Nuclear structure with radioactive ion beams • Atomic physics
Experimental Challenges 25 AGeV Au+Au, UrQMD+GEANT4 • reconstruction of ≈1000 charges particles per event, kinematically focussed • extremely rare probes: D, J/ψ (10-5 – 10 -4) • high rates: up to 107/s (beam 109/s) • displaced vertex determination accuracy ≈ 50 μm • hadron & lepton ID
The CBM Detector • Radiation hard Silicon Tracking System in dipole field • Electron ID in RICH+TRD+ECAL • Hadron ID in TOF (RPC) • γ, μ, π in ECAL • High-speed DAQ and trigger system
Detector R&D after 1 MRad R&D ongoing and promising Charge [ADC] Radiation hardness of pixel sensors RICH optical layout Radiator gas, mirror material, photodetectors TRD rate capability RPC rate capability and large area coverage
Simulations – Level of Reality Full track reconstruction (STS) Pattern recognition in RICH Primary & secondary vertex reconstruction Global tracking under work
Acceptance for TOF-identified Hadrons Bulk of hadrons can be identified by STS + TOF Improvement for kaons by RICH (?)
Performance for Hyperons Ξ- Ω- Λ 7.7% 6.7% 15.8% Hyperons reconstructable almost background-free
Performance for D mesons Au+Au @ 25 AGeV, 1012 events min bias, full track and vertex reconstruction D multiplicity taken from HSD, background UrQMD no PID of secondaries D0 D+ 80,000 D+ in 1012 min bias events 1 day of full luminosity running 100 days with today´s MAPS performance
15 AGeV Au+Au 25 AGeV Au+Au 35 AGeV Au+Au Performance for J/ψ via e+e- assumed pion suppression 10-4 studies ongoing
data mixed events Performance for Flavour Fluctuations UrQMD Au+Au, 25 AGeV sensitive to fluctuations within 1 %
The Muon Option C/Fe absorbers + detector layers Promising for J/ψ Low efficiency for soft muons Low efficiency for invariant masses below 0.5 GeV Very challenging muon detector (high densities)
The CBM Physics Group • established June 2005 • 1st CBM Physics Workshop December 2005, GSI • 2nd Physics Workshop: June 2006, ECT Trento • CBM Physics Book in ≈ 1 year
CBM: Status Nov. 2001: FAIR Conceptual Design Report Jul. 2002: FAIR Recommendation by german Wissenschaftsrat Feb. 2003: FAIR approved by BMBF Jan. 2004: CBM Letter of Intent approved "core experiment of FAIR" Jan. 2005: CBM Technical Status Report June 2005: CBM Physics Group established March 2006: Fed. Gouvernment: FAIR in budgetary plan up to 2014 2007: CBM Technical Proposal http://www.gsi.de/fair/experiments/CBM
The CBM collaboration Croatia: RBI, Zagreb China: Wuhan Univ. Hefei Univ. Cyprus: Nikosia Univ. Czech Republic: CAS, Rez Techn. Univ. Prague France: IReS Strasbourg Hungaria: KFKI Budapest Eötvös Univ. Budapest India: VECC Kolkata Korea: Korea Univ. Seoul Pusan National Univ. Norway: Univ. Bergen Germany: Univ. Heidelberg, Phys. Inst. Univ. HD, Kirchhoff Inst. Univ. Frankfurt Univ. Kaiserslautern Univ. Mannheim Univ. Münster FZ Rossendorf GSI Darmstadt Poland: Krakow Univ. Warsaw Univ. Silesia Univ. Katowice Portugal: LIP Coimbra Romania: NIPNE Bucharest Russia: IHEP Protvino INR Troitzk ITEP Moscow KRI, St. Petersburg Kurchatov Inst., Moscow LHE, JINR Dubna LPP, JINR Dubna LIT, JINR Dubna MEPHI Moscow Obninsk State Univ. PNPI Gatchina SINP, Moscow State Univ. St. Petersburg Polytec. U. Ukraine: Shevshenko Univ. , Kiev 40 institutions, ≈ 350 Members