Experiment CBM – research program Paweł Staszel Jagiellonian University  Physics motivation  Detector concept  Feasibility study  Status

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Diagram fazowy QCD

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce QCD Phase Diagram scan with A+A collisions V.Toneev et al., nucl-th/ component hydrodynamics + hadron gas EOS: Critical Point reached at trajectory for ~30 AGeV (√s NN =7.74) Phase Boundary reached already at ~10 AGeV (√s NN =4.72)

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce How to explore interesting regions of the QCD Phase Diagram Lattice QCD calculations: Fedor & Katz, Ejiri et al. Freeze-out phase can be studied by measurement of „soft” hadrons production (bulk observables)‏ Information about earlier phases is carried by rare probes: High p T particles Particles decaying in to leptons Particles build up of heavy quarks (  J/ψ, D, Λ c.... )‏ and by collective motion (flow) of the created soft medium. (e.g. v 2 is sensitive to the quanta interaction just after the medium formation) large advantage from simultaneous flow measurement of “ordinary” hadrons and rare probes

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Experymental arguments for Phase Transition at low SPS energy NA49 (QM 2004) ‏ None monotonic behaviour of K + /  + ratio Effective temperature shows plateau in the range of SPS energy

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Hadrons in dense medium (->e + e - ) ‏ Top SPS: excess of e + e - pairs around 0.5 GeV (by factor of ~2.8)‏ 40AGeV: the excess rised up to ~4 → strong dependency on  B Rapp-Wambach –  in-medium modification Rapp: “dropping mass” according to Brown-Rho scaling scenario Thermal model

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Hadrons in dense medium (->  +  - ) ‏ NA60, Nucl. Phys. A 774 (2006) 67 broadening of   spectral function (Rapp-Wambach) ‏ contradiction with mass drop scenario (Brown-Rho scaling) ‏ excess by factor of 4 over the “cocktail” with 25% systematic uncertainty ! ‏

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce J/ Ψ suppression Anomalous J/ψ suppresion (AS) on SPS, L – effective path in medium NA50, QM 2005 NA60 evidenced same effect in In+In Better scaling is obtained in N part ; onset already at N part ~90, At lower energies (larger μ B ) one can expect onset of AS for more central collisions can → dependency on energy density and μ B Important measurement of open charm to verify other scenarios

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Open Charm in dense medium ‏ Mishra et al, nucl- th/ Reduction in the effective mass of D-meson can open D-Dbar decay channel for charmonium states → possible explanation for the J/ Ψ suppression, CBM=> simultaneous measurement of J/ Ψ and D-mesons

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Critical point critical region might be small focussing effect? fluctuations would need time to develop [Schaefer, Wambach, PRD75, (2007)][Asakawa, Bass, Mueller, Nonaka, PRL 101, (2008)]

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Elliptic flow KE T =m T -m all particles flow (even D-mesons!) scaling if taking the underlying number of quarks into account! → like (all!) quarks flow and combine to hadrons at a later stage (hadronisation) data can only be explained assuming a large, early built up pressure in a nearly ideal liquid (low viscosity!) baryons n=3 mesons n=2 [PHENIX, PRL.98:162301,2007]

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Elliptic flow data at top SPS support hypothesis of early development of collectivity influence of hadronic rescattering phase, resonance decay? lack of complete thermalization, viscosity effect? larger pt-range needed Pb+Pb collisions, √s NN = 17.3 GeV [NA49, G. Stefanek, PoS CPOD2006:030,2006]

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Event-by-event fluctuations [NA49 collaboration, arXiv: v2 [nucl-ex]]arXiv: v2 observation might become enormously difficult correlation length  of sigma field, may become rather small for a finite lifetime of the fireball large acceptance needed! [Stephanov, Rajagopal, Shuryak, PRD60, (1999)] 1st try to identify 1st order phase transition line fluctuations, correlations with large acceptance and particle identification

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce CBM: Physics topics and Observables Onset of chiral symmetry restoration at high  B in-medium modifications of hadrons ( , ,   e + e - (μ + μ - ), D )‏ Deconfinement phase transition at high  B excitation function and flow of strangeness (K,  )‏ excitation function and flow of charm (J/ψ, ψ', D 0, D ,  c )‏ charmonium suppression, sequential for J/ψ and ψ' ? corelated with open charm ? The equation-of-state at high  B collective flow of hadrons particle production at threshold energies (open charm) QCD critical endpoint excitation function of event-by-event fluctuations (K/π,...)‏ predictions? clear signatures? → prepare to measure "everything": bulk particles and rare probes ⇒ probing medium with known overall characteristics → systematic studies! (pp, pA, AA, energy)‏

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Heavy Ion Experiments (selection) time (advance in technology)‏ LH C RHI C SPS SIS300 SIS18Bevalac SIS 100 AGS  Inner Tracker  HPID TPC upgrade C B M GAP

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce CBM Detector (->e + e - ) ‏ TRDs (4,6,8 m)‏ STS ( 5 – 100 cm)‏

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce CBM Detector (->  +  - ) ‏ beam ABSORBER (1,5 m)‏ TRDs (4,6,8 m)‏ TOF (10 m)‏ ECAL (12 m)‏ STS ( 5 – 100 cm)‏ magnet

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Silicon Tracking Station – heart of CBM Challenge: high track density:  600 charged particles in  25 Tasks: track reconstruction: 0.1 GeV/c < p  GeV/c  p/p ~ 1% (p=1 GeV/c) primary and secondary vertex reconstruction (resolution  50  m) V 0 track pattern recognition c  = 312  m radiation hard and fast silicon pixel and strip detectors self triggered FEE high speed DAQ and trigger online track reconstruction!

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Simulation: rare probes D0D0 cc J/   di-electrons di-muons '' ''

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Simulation: bulk particles and hyperons ‏ incl. TOF 1035 AGeV Λ Ξ Ω hadrony są “dobrze widziane”

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Hiperons: PID from decay topology in STS  

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Status CBM Collaboration undergoes (phase) transition simulation → prototyping

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Double and triple GEM detectors 2 Double-sided silicon microstrip detectors Radiation tolerance studies for readout electronics Full readout and analysis chain: Front-end board with self-triggering n-XYTER chip Readout controller Data Acquisition System online offline Go4Go4 Analysis Detector signals Successful test of CBM prototype detector systems with free-streaming read-out electronics using proton beams at GSI, September 28-30, 2008 GSI and AGH Krakow VECC Kolkata KIP Heidelberg

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce CBM hardware R&D RICH mirror n-XYTER FEB Silicon microstrip detector MVD: Cryogenic operation in vacuum RPC R&D Forward Calorimeter GEM dipole magnet

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce CBM Collaboration China: Tsinghua Univ., Beijing CCNU Wuhan USTC Hefei Croatia: University of Split RBI, Zagreb Portugal: LIP Coimbra Romania: NIPNE Bucharest Bucharest University Poland: Krakow Univ. Warsaw Univ. Silesia Univ. Katowice Kraków AGH (Inst. Nucl. Phys. Krakow) LIT, JINR Dubna MEPHI Moscow Obninsk State Univ. PNPI Gatchina SINP, Moscow State Univ. St. Petersburg Polytec. U. Ukraine: INR, Kiev Shevchenko Univ., Kiev Univ. Mannheim Univ. Münster FZ Rossendorf GSI Darmstadt Czech Republic: CAS, Rez Techn. Univ. Prague France: IPHC Strasbourg Germany: Univ. Heidelberg, Phys. Inst. Univ. HD, Kirchhoff Inst. Univ. Frankfurt Hungaria: KFKI Budapest Eötvös Univ. Budapest India: Aligarh Muslim Univ., Aligarh IOP Bhubaneswar Panjab Univ., Chandigarh Gauhati Univ., Guwahati Univ. Rajasthan, Jaipur Univ. Jammu, Jammu IIT Kharagpur SAHA Kolkata Univ Calcutta, Kolkata VECC Kolkata Univ. Kashmir, Srinagar Banaras Hindu Univ., Varanasi Korea: Korea Univ. Seoul Pusan National Univ. Norway: Univ. Bergen Kurchatov Inst. Moscow LHE, JINR Dubna LPP, JINR Dubna Cyprus: Nikosia Univ. 55 institutions, > 400 members Dubna, Oct 2008 Russia: IHEP Protvino INR Troitzk ITEP Moscow KRI, St. Petersburg

Paweł StaszelV Polish Workshop on Relativistic Heavy-Ion Collisions, Kielce Mapping the QCD phase diagram with heavy-ion collisions net baryon density:  B  4 ( mT/2  h 2 c 2 ) 3/2 x [exp((  B -m)/T) - exp((-  B -m)/T)] baryons - antibaryons Lattice QCD calculations: Fedor & Katz, Ejiri et al. SIS30 0