Schwerionen- und Hadronenphysik an und Claudia Höhne, GSI Darmstadt KHuK Jahrestagung, 25./ , GSI Darmstadt Einleitung GSIFOPI & HADES FAIRHADES & CBM Zusammenfassung & Ausblick

Claudia Höhne KHuK Jahrestagung, 2007, GSI2 The QCD phase diagram aim of heavy ion physics explore the QCD phase diagram! study hadronic properties at high baryon densities chiral symmetry restoration? FOPI & A+A collisions at < 2 GeV/nucleon A+A collisions at 2-10 GeV/nucleon A+A collisions at 10 – 45 GeV/nucleon [Andronic et al. Nucl. Phys. A 772, 167 (2006).

Claudia Höhne KHuK Jahrestagung, 2007, GSI3 The SIS18 heavy ion regime t [fm/c] ≈ 10 fm/c Probing nuclear matter at “moderate" baryon density and temperature A long life time of the dense system (up tp 10 fm/c) The all-dominant presence of baryonic resonances (“resonance matter”), N  /A part ≈ 10% The sub-threshold production of Kaons and Vector Mesons: Multi-step processes confined to the dense phase

Claudia Höhne KHuK Jahrestagung, 2007, GSI4 Kaons in medium Modified properties of hadrons in dense baryonic matter? → mass, width, phase-space and angular distributions in-medium kaon energy ↔ equation of state in dense matter? attractive K - N potential repulsive K + N potential (yellow area: envelope of several microscopic calculations: all predict the same trend !)

Claudia Höhne KHuK Jahrestagung, 2007, GSI5 FOPI – SIS Motivation hadronic properties in dense medium (1-3  0 )? strangeness! (production close to threshold) → sensitive probe! Kaons in medium yields, phase space distributions, flow Strange Resonances Baryons! Excited hyperon  *(1385) → total strangeness, thermalisation? Exotica – kaonic bound states IPNE Bucharest, RomaniaITEP Moscow, Russia CRIP/KFKI Budapest, HungaryKurchatov Institute Moscow, Russia LPC Clermont-Ferrand, FranceKorea University, Seoul, Korea GSI Darmstadt, GermanyIReS Strasbourg, France + IMP Lanzhou, China FZ Rossendorf, GermanyUniv. of Heidelberg, Germany + SMI Vienna, Austria Univ. of Warsaw, PolandRBI Zagreb, Croatia + TUM, Munich, Germany

Claudia Höhne KHuK Jahrestagung, 2007, GSI6 Kaon – flow measurements directed flow: elliptic flow: Sensitivity of collective flow to depth of kaon potential → U(K + ) = + 20 MeV, For K - no consistent description yet by transport models: HSD ↔ IQMD Y.J.Kim (FOPI) 1.93 AGeV

Claudia Höhne KHuK Jahrestagung, 2007, GSI7 Strange resonances  * (1385) subthreshold production, X. Lopez et al. (FOPI collaboration), submitted to PRL (2007) for investigation of total strangeness production baryons (  !) are important! → test thermalization/ chemical equlibrium with statistical model short lived resonances (e.g.  *) are expected to be also sensitive to dense medium! due to short lifetime  * should probe finite density! Broadening of the width not yet observed (needs more statistics)  * in-medium: Γ = 76 MeV at ρ = ρ 0 Mean mass: attractive potential ≈ - 45 MeV at ρ 0  *   +  (88  2%)  = 39.4 MeVc  = 5 fm

Claudia Höhne KHuK Jahrestagung, 2007, GSI8 FOPI TOF upgrade completed! FOPI – RPC detector: 4500 electronic channels, 6m 2 active area

Claudia Höhne KHuK Jahrestagung, 2007, GSI9 Online performance from 1. experiment (Sep.2007) K + - identification by momentum – TOF analysis up to p lab =1GeV/c System time resolution estimate from fast pions:  t = 100 ps P (GeV/c) v (cm/ns)  t = t meas – t tracking (ns) p  >0.5GeV/c ++ -- K+K+ p

Claudia Höhne KHuK Jahrestagung, 2007, GSI10 Summary of FOPI physics program (2008 – 2010) 2008 (S338): Heavy ion reactions Ru AGeV,4 weeksStrange resonance production Ni + 2 AGeV,2 weeksand flow  K - - potential 2009 (S339): Pion induced reactions   + LH 2, C, 1.7 GeV/c,2 weeksStrangeness production K - - potential at  =  (S349): Proton induced reactions p + 3 GeV,2 weeksSearch for ppK - - bound state (accepted proposals by G-PAC)

Claudia Höhne KHuK Jahrestagung, 2007, GSI11 In-medium properties of hadrons (electromagnetic-probes) [Rapp, Wambach, Adv. Nucl. Phys. 25 (2000) 1, hep-ph/ ]  -meson couples to the medium, direct radiation from the early phase vector-meson dominance! vacuum lifetime  0 = 1.3 fm/c → dileptons = penetrating probe connection to chiral symmetry restoration? p n  ++  p   e +, μ + e -, μ -   -meson spectral function

Claudia Höhne KHuK Jahrestagung, 2007, GSI12 HADES High Acceptance DiElectron Spectrometer –Focus on the spectroscopy of vector mesons (  ) –Consistent picture in pp, pA,  A and AA reactions –Supplemented by hadron spectroscopy, incl. K 0 s, ,  Spectrometer with a … –High geometric acceptance & invariant mass resolution –High background rejection & rate capability, dedicated LVL2 trigger Instrumental challenge!  → e + e - rare probe: 1 e + e - decay from vector mesons per 1-10 Million reactions! –Large background from conversion and  0 -Dalitz decay

Claudia Höhne KHuK Jahrestagung, 2007, GSI13 preliminary Dileptons from C+C excess of dilepton yield above cocktail! relative excess for 1 GeV/nucleon is larger than for 2 GeV/nucleon shape of relative excess similar "cocktail A" =  0 +  +  (long lived) [HADES, PRL 98, (2007)]

Claudia Höhne KHuK Jahrestagung, 2007, GSI14 Quantitative analysis: deduce the absolute excess yield Y exc (beyond η), making use of the TAPS η data: C + C 2 AGeV Phys. Rev. Lett. 98, (2007) Y exc (2.0)/Y exc (1.0) = 2.3 ± 0.6(stat) ± 1.0(sys) Dileptons from C+C (II) preliminary HADES confirms DLS! excess (beyond η) scales like pions → importance of resonances! discussions ongoing

Claudia Höhne KHuK Jahrestagung, 2007, GSI15 Comparison to DLS DLS data (C+C, 1AGeV) confirmed by HADES! preliminary DLS Data: R.J. Porter et al.: PRL 79(97)1229 extrapolation of HADES data to DLS acceptance theory is challenged to explain data!

Claudia Höhne KHuK Jahrestagung, 2007, GSI16 Comparison HSD - HADES comparison of HADES data to HSD (new version including new isospin dependent Bremsstrahlung) lively discussions ongoing! → compare to p+p and p+n data! [E. Bratkovskaya, priv. comm.] HADES strategy: establish experimental "cocktail" of long and short lived e + e - pairs from pp and pn data (s<s thres for  production) study exclusive channels (e.g.  + ) in pp by missing mass spectroscopy

Claudia Höhne KHuK Jahrestagung, 2007, GSI17 100% statistic analyzed : signal pairs, 607 for M>150 MeV/c 2 50% statistic analyzed: signal pairs, 1230 for M>150 MeV/c 2 Online spectrum (data from May 2007 )Preliminary not efficiency corrected spectrum preliminary p+p, d+p  e + e - X, 1.25 GeV

Claudia Höhne KHuK Jahrestagung, 2007, GSI18 HADES schedule Physics Runs in… p, d,  - induced A + AStatus/Comment 2002C + C 2 AGeVPublished! (PRL) 2004C + C 1 AGeVAnalysis finished 2004p + p 2.2 GeVAnalysis finished 2005Ar + KCl 1,75 AGeVAnalysis ongoing 2006p + p 1.25 GeVAnalysis ongoing 2007p + p 3.5 GeV d + p 1.25 AGeV … online results! 2008p + A 3.5 GeV 2008/9Upgrade RPC, DAQ > 2008  + N, A Ni + Ni Au + Au planned > 2014Hades goes FAIR (8 AGeV) "DLS puzzle" elementary reactions! exclusive channels  -beam! chiral symmetry restoration for  =  0 in controled system heavy systems!

Claudia Höhne KHuK Jahrestagung, 2007, GSI19 HADES upgrade for heavier systems RPC (TOF with higher granularity, 80ps time resolution) DAQ (LVL1 rates beyond 30 KHz) HADES at FAIR

Claudia Höhne KHuK Jahrestagung, 2007, GSI20 High density matter at FAIR [Bratkovskaya et al., PRC 69 (2004) ] UrQMD calculation of T,  B as function of reaction time (open symbols – nonequilibrium, full symbols – appr. pressure equilibrium) CBM rare probes! (charm, dileptons) sensitive to medium... and bulk properties aim for microscopic understanding higher energies (2-45 GeV/nucleon) → higher baryon densities, temperatures, energy densities created; but still over time span of 5-10 fm/c discovery potential:1st order deconfinement phase transition? critical point? chiral phase transition?

Claudia Höhne KHuK Jahrestagung, 2007, GSI21 Charm production at threshold [W. Cassing et al., Nucl. Phys. A 691 (2001) 753] HSD simulations CBM will measure charm production at threshold → after primordial production, the survival and momentum of the charm quarks depends on the interactions with the dense and hot medium! → direct probe of the medium! do c and c quarks behave differently in baryon-rich matter? charmonium (cc) in hot and dense matter? relation to deconfinement?

Claudia Höhne KHuK Jahrestagung, 2007, GSI22 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' ? The equation-of-state at high  B collective flow of identified hadrons particle production at threshold energies (open charm) QCD critical endpoint excitation function of event-by-event fluctuations (K/π,...) mostly new measurements CBM Physics Book (theory) in preparation

Claudia Höhne KHuK Jahrestagung, 2007, GSI23 CBM collaboration Russia: IHEP Protvino INR Troitzk ITEP Moscow KRI, St. Petersburg China: CCNU Wuhan USTC Hefei Croatia: University of Split RBI, Zagreb Portugal: LIP Coimbra Romania: NIPNE Bucharest Poland: Krakow Univ. Warsaw Univ. Silesia Univ. Katowice Nucl. Phys. Inst. Krakow LIT, JINR Dubna MEPHI Moscow Obninsk State Univ. PNPI Gatchina SINP, Moscow State Univ. St. Petersburg Polytec. U. Ukraine: Shevchenko Univ., Kiev 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 Univ. Mannheim Hungaria: KFKI Budapest Eötvös Univ. Budapest India: Aligarh Muslim Univ., Aligarh IOP Bhubaneswar Panjab Univ., Chandigarh 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 51 institutions, > 400 members Dresden, September 2007 Cyprus: Nikosia Univ.

Claudia Höhne KHuK Jahrestagung, 2007, GSI24 The CBM experiment tracking, momentum determination, vertex reconstruction: radiation hard silicon pixel/strip detectors (STS) in a magnetic dipole field hadron ID: TOF (& RICH) photons,  0,  : ECAL electron ID: RICH & TRD   suppression  10 4 PSD for event characterization high speed DAQ and trigger (up to 10 MHz int. rates) → rare probes! muon ID: absorber + detector layer sandwich  move out absorbers for hadron runs MVD + STS... measuring both channels would be the best crosscheck of results we can ever do!

Claudia Höhne KHuK Jahrestagung, 2007, GSI25 STS tracking – heart of CBM Challenge: high track density  600 charged particles in  25 o Task 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 D + →  +  + K - (c  = 317  m) D 0 → K -  + (c  = 124  m) silicon pixel and strip detectors → drives CBM layout!

Claudia Höhne KHuK Jahrestagung, 2007, GSI26 STS and FEE R&D Strip sensor development with CIS Erfurt First test sensor delivered spring 2007 Fast self-triggered readout chip n-XYTER in collaboration with DETNI prospect: CBM-XYTER

Claudia Höhne KHuK Jahrestagung, 2007, GSI27 CbmRoot simulation framework detector simulation (GEANT3) full event reconstruction: track reconstruction, add RICH, TRD and TOF info result from feasibility studies in the following: central Au+Au collisions at 25 AGeV beam energy (UrQMD)

Claudia Höhne KHuK Jahrestagung, 2007, GSI28 Open charm production D 0 → K -  + and D 0 → K +  - (c  = 124  m), full event reconstruction = 1.5 ∙ (central Au+Au collisions, 25 AGeV) first pixel detector (MAPS) at 10cm ~53  m secondary vertex resolution proton identification with TOF central Au+Au collisions, 25 AGeV 25 AGeV central AuAu

Claudia Höhne KHuK Jahrestagung, 2007, GSI29 Low mass vector mesons invariant mass spectra electrons: pt > 0.2 GeV/c background dominated by physical sources (75%) muons: intrinsic p>1.5 GeV cut (125 cm Fe absorber), use TOF information electrons: 200k eventsbackground 4 ∙10 8 events – signal 20k ev. All e + e - Comb. bg ρ  e + e -   e + e - φ  e + e - π 0  γ e + e -   π 0 e + e - η  γ e + e -   m = 14 MeV/c 2   m = 11 MeV/c 2 25 AGeV central AuAu

Claudia Höhne KHuK Jahrestagung, 2007, GSI30 electrons: 2.4 ∙10 10 events J/   m = 38 MeV/c 2  '  m = 45 MeV/c 2 J/  and  ' invariant mass spectra electrons: p 1 GeV, 1‰ interaction target (25  m Au) muons: 225 cm Fe absorber, no pt-cut muons: 4 ∙10 8 events J/   m = 22 MeV/c 2  '  m = 33 MeV/c 2 25 AGeV central AuAu

Claudia Höhne KHuK Jahrestagung, 2007, GSI31 Summary & Outlook succesful investigation of hadronic matter at moderate densities (1-3  0 ) data on elementary interactions and serious theoretical effort essential! FOPI→ sensitivity of kaons to dense medium demonstrated → quantify medium modifications for strange hadrons → multi-strange clusters? HADES→ "DLS puzzle" solved → setup completed, production phase of high quality data → broad program (e.g. p,  A, Au+Au), upgrade and move to FAIR investigate high baryon density region of QCD phase diagram (deconfinement phase transition, chiral symmetry restoration) CBM → comprehensive investigation including rare probes (dileptons and charm) → detailed simulations, R&D ongoing complementary effort to LHC

Claudia Höhne KHuK Jahrestagung, 2007, GSI32 Backup

Claudia Höhne KHuK Jahrestagung, 2007, GSI33 Vector Mesons: p+p, 3.5 GeV May 2007 May 2007, preliminary, online results! No final calibration/alignment! Hadron analysis: missing mass technique Hadron analysis: missing mass technique: –pp 4-prong (+++-)- selection –<2% of statistics –pp  pp  +  0  - –pp  ppK + K - e + e - pair analysis e + e - pair analysis: –  not shifted! Preliminary calibration… –Extra yield below VM pole mass. pp missing mass (GeV/c 2 ) yield (a.u.) η  pp  pp  +  0  - pp missing mass (GeV/c 2 ) Yiel (a.u.) pp  ppK + K - S/B M ee M ee Preliminary PRELIMINARY