Future Experiments with HADES at FAIR Pavel Tlustý, NPI Řež “near future” - experiments on SIS18 in ? - upgrade of the HADES spectrometer experiments with HADES on SIS100 at FAIR in CHIRAL 2010 workshop, Valencia, June 21-24, 2010 June 24, 2010

2 2.2 GeV (2004) „ Anomalous” excess of e + e - pairs at intermediate masses  verify DLS data NN bremsstrahlung and  Dalitz decays vector mesons  /  in-medium p+p Resonance ( ,N * ) production, formfactors and studies of  /  Dalitz decays (helicity angles) C+C 2.0 AGeV (2002) 1.0 AGeV (2004) 1. p+p 1.25 GeV (2006) d+p 1.25 GeV (2007) 2. Ar+KCl 1.76 GeV (2005) Evolution of e + e - yield Strangeness: , K ±,0,  GeV (2007) p+Nb 3.5 GeV (2008) p+p 4. Completed physics program

3 Yield/A part Ar+KCl Ca+Ca Observed systematics of “excess" Scales with E beam like  production Scales with A part stronger than linear: ≈ 1.4 “Excess” vs. beam energy and system size

Vector mesons larger system – better precision needed for differential studies reference spectrum (NN)- peripheral reactions, d+p, ? can one see in-medium effects on vector meson?

5 Ar+KCl data compared to IQMD K 0 - N potential Data compared to the IQMD. Version with potential preferred.  Consistent with KN-potential with a strength of U=39   extrapolation from high density to  0 (IQMD)  +A & p+A data (FOPI & ANKE) consistent with U = 20  5 MeV at  =  0 extrapolation from low density to  0 (HSD)

Kaon flow sideward out-of plane(eliptic) Y. Shin et. al. (KAOS) PRL 81 (1998) 1576 W. Cassing et al., NPA 727 (2003) 59, E. Bratkovskaya, priv. com. Coupled channel G-Matrix approach (K - spectral functions): L. Tolos et al., NPA 690 (2001) 547 K+K+

Kaon flow sideward out-of plane(eliptic) W. Cassing et al., NPA 727 (2003) 59, E. Bratkovskaya, priv. com. Coupled channel G-Matrix approach (K - spectral functions): L. Tolos et al., NPA 690 (2001) 547 M. Płoskon, PhD Thesis, Univ. Frankfurt 2005

Physics Program on SIS18 – Heavy Ions combined measurement of dielectron and strangeness production in heavy systems Dielectrons: Studies of properties of the low-mass, i.e < Me+e− < 0.5 GeV/c 2 dielectron excess Vector meson (ρ/ω/φ) spectroscopy in the dielectron channel Strangeness: φ meson production via the K+K− decay channel K 0, K + and K − production characteristics by means of transverse momentum, rapidity and flow measurements Studies of strange baryon production: Λ(1115),Σ(1385) and Ξ − (1321) Search for kaonic clusters Studies of HBT correlations

9 Hades Upgrade Project Aim: heavy systems at SIS18 and SIS100 RPC performance (beam test) Efficiency above 95 % Time res ps Negligible crosstalk < 1% List of HADES upgrade subprojects: RPC - Resistive Plate Chamber FINISHED  Time res ps, high granularity Forward Wall FINISHED   range 0.2 – 7 degrees, reaction plane DAQ-Upgrade (RICH, MDC, FWALL, TOF, SHOWER)  goal 20kHz for Au+Au LVL1 ON GOING MDC I rebuild  system stability FINISHED End of 2010: HADES ready for heavier systems Multipurpose Trigger Readout Board TRB: 4 TDC – 128 channels (HPTDC), 4x512Mb SDRAM, FPGA – Virtex4LX40, ETRAX, FS – 4 processors, 100Mb/s,TCP/IP, 2,5 Gb/s optical link, DSP TigerSharc, DC/DC converters,

10 Simulations – tracking study Tracking ready to be used in high multiplicity environment Secondary vertex reconstruction not ready Tracking optimization on-going to be verified with HI beam

11 A Large excess (~8) expected from Ar+KCl excess scaling above the NN reference Differential studies of excess possible: centrality, dN/dm t, angular distributions… Triggers for peripheral and central reactions. Use peripheral reactions for a comparison with the NN reference. (pp+pn)/2  Dalitz   oo baryonic radiation Collision systems for HI runs: Highest possible energy  high VM and strangeness production Largest possible colliding systems  increase compression and medium effects Au(71 + ) AGeV - similar to pp, np data Ag(46 + ) – 1.65 AGeV - comparable with Ar+KCl (1.75 AGeV) Medium effects for intermediate masses

12 Sensitivity to medium effects for VM VM in HI coll. : regeneration and absorption - N e+e- ~  e+e- T fireball HSD + Dropping mass & mass broadenning AGeV trigger (25% ot total cross section) with 10 KHz Ag+Ag : maximal density  VM production rate direct comparison to Ar+KCl possible

Strangeness : count rate estimates counts/day for semicentral LVL1 assuming efficiencies & production rates from ArKcl more than in ArKcl ~ ! ! ! - acc(RPC) x trigger rate (no LVL2 )

Simulations: strangeness K - identification acceptance purity (no dE/dx used) large acceptance: mid rap. coverage very good K - purity up to p t < 800 MeV/c

Beam/target and Trigger setting, Shift request Beam/target and Trigger setting, Shift request Two beam/target combinations 197 Au Au at 1.25 A GeV 107 Ag Ag at 1.65 A GeV Beam intenisty ~2*10 7 /spill(5s) 1% interaction target (12 segments) LVL1 trigger settings (~20 kHz total): minimum-bias semicentral (25% total cross section) Shift request: Au + Au days (120 shifts) Ag + Ag days (150 shifts)

16 FAIR facility at GSI SIS100 beam energies: ions up to 14 A GeV (Au79 + – 11.2 AGeV) protons up to 29 GeV B. Sharkov +1 year

17 HADES/CBM cave design W. Niebur

18 Di-electrons at SIS100 (2-10 AGeV), motivation No di-electron data exist in this energy range Extension of the HADES physics program Enhance production of Vector Mesons: SIS18  SIS 100 subthreshold production  above threshold  better signal, precise line shape determination  reference data for SIIS300 S. Vogel et al.Phys. Rev. C (2008) 2AGeV 11AGeV 30AGeV HADES at SIS100: - running experiment, well understood performance - currently conducted upgrade will improve stability, DAQ and time resolution of the Spectrometer - easy transfer to FAIR, experienced crew - can deliver high quality data

19 Di-electrons at SIS 100   e + e − acceptance Acceptance for di-electrons from ω->e+e− (2 AGeV and 8 AGeV) Direct ω decay: PLUTO, ω from thermal model Single leptons filtered with HADES acceptance 9 0 opening angle cut was applied Acceptance: 2 AGeV 33 % 8 AGeV 21 % Number of  's in acceptance increase by a factor of ~50

20 Di-electrons at SIS 100 – invariant mass Di-electron invariant mass for various systems: ( C+C 2 AGeV and 8 AGeV, Au+Au 1 AGeV and 8 AGeV ) All dilepton sources generated by PLUTO, hadronic and electromagnetic decays Single leptons filtered with HADES acceptance Lepton momentums smeared 9 0 opening angle cut was applied 1.0 AGeV Realistic simulation in preparation

21 Hadrons at SIS 100 – acceptance URQMD and PLUTO events filtered with HADES acceptance midrapidity covered at both 2.0 and 8.0 AGeV 15 % reduction at 8 AGeV for π 40 % reduction at 8 AGeV for K 8 A GeV 2 A GeV

22 Occupancy estimation at 8 AGeV Simulated events Central Au+Au at 1.5 AGeV and 8 AGeV, C+C at 2.0 AGeV and 8 AGeV HGeant used for a realistic detector modeling Main outcome From C+C at 2.0 AGeV  Au+Au at 1.5 AGeV (SIS18) - factor of 14 At Au+Au at 1.5 AGeV expected 20% double hit probability !!!  corresponds to Ni+Ni at 8 AGeV - heaviest system at SIS 100

23 Calorimeter project For pair excess determination a precise knowledge of the hadronic cocktail is needed (particle yields at chemical freeze-out) At 2-40 AGeV mainly dominated by η-Dalitz Normalization to π 0 (at SIS18 – TAPS data)  Calorimeter for HADES  π 0, η measurement  improved pion suppression Side View START Electromagnetic calorimeter for HADES ( ) substitute for Pre-Shower (18º<Θ<45º, 8 m 2 ;18 tons)  el/  separation,  º and η Dalitz,...

24 Calorimeter project Millstones achieved: Test at MAMI, lead glass modules from OPAL  energy resolution for photons K. Lapidus, Eliane Epple, simulation  the parameterization lookup table almost ready, detailed, fast simulation will be possible Mechanical construction –  general concept ready, approved by HADES construction engineer, U. Kopf 5.4% / sqrt(E)

25 Calorimeter project Millstones achieved: Measure the pion rejection and compare this to the simulation HADES ECM test in CERN T10 (F.Guber), HADES – NA61 collaboration May Millstones to be achieved: FE electronics pi0 reconstruction in beam test

26 Summary and outlook  Di-electron radiation from the HI collision at SIS 18 is being investigated in a very systematic, model independent way. investigated in a very systematic, model independent way. No medium effects observed for light systems (C+C) No medium effects observed for light systems (C+C) The "reference spectrum" based on elementary reactions established The "reference spectrum" based on elementary reactions established for heavier systems (Ar+KCl) for heavier systems (Ar+KCl) First VM signal measured at SIS 18 in Ar+KCl collisions First VM signal measured at SIS 18 in Ar+KCl collisions Modification of the  meson properties in-medium (p+Nb) under investigation Modification of the  meson properties in-medium (p+Nb) under investigation  Interesting physics program for future proposals of HADES at SIS 18 ( Au+Au, Ag+Ag,  − beam )  SIS100 – a natural way of the physics programme extension The device is ready to take high quality data The device is ready to take high quality data Easy installation at SIS 100 Easy installation at SIS 100 VM produced above the production thresholds VM produced above the production thresholds High acceptance for direct decays of VM over whole energy High acceptance for direct decays of VM over whole energy regions of SIS 18 and SIS100 regions of SIS 18 and SIS100 (from 33 % at SIS 18 to 22 % at SIS100) (from 33 % at SIS 18 to 22 % at SIS100)  Waiting for FAIR

27 The HADES Collaboration Cyprus: Department of Physics, University of Cyprus Czech Republic: Nuclear Physics Institute, Academy of Sciences of Czech Republic France: IPN (UMR 8608), Université Paris Sud Germany: GSI, Darmstadt FZ Dresden-Rossendorf IKF, Goethe-Universität Frankfurt II.PI, Justus Liebig Universität Giessen PD E12, Technische Universität München Italy: Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud Istituto Nazionale di Fisica Nucleare, Sezione di Milano Poland: Smoluchowski Institute of Physics, Jagiellonian University of Cracow Portugal: LIP-Laboratório de Instrumentação e Física Experimental de Partículas 17 institutions 120members Russia: INR, Russian Academy of Science Joint Institute of Nuclear Research ITEP Spain: Departamento de Física de Partículas, University of Santiago de Compostela Instituto de Física Corpuscular, Universidad de Valencia-CSIC

28 Backup slides

Kaonic Nuclear clusters Stat. model predictions for cluster formation in Au-Au collisions promising candidate ?: K - pp system predictions from theory : MeV binding energy, hadronic decay into  p experimental evidences : FINUDA K - absorption on nucleus M (  p) = 2255±7 MeV/c 2,  = 67 ± 14 MeV/c 2 M. Agnello et al., PRL 94, (2005). DISTO p + p -> K + + X X->  p M X = 2265 ± 2 (stat) ± 5 (syst) MeV/c 2  X = 118 ± 8 (stat) ± 10 (syst) MeV/c 2 RMS radius of (  p) < 1.7 fm ! Y. Yamazaki et al..arXiv: R. Kotte : (  p) source in ArKcl but  no sensitivity to  p potential and..no signal in  p inv. mass visible

30 Experiments with pion beams The GSI secondary pion beam line Mom. det. of the beam particles with precision 0.3% for exclusive reconstruction  Tracking in the beam line needed: silicon strip detector

31 Pion beam project - beam detectors Beam tracking Si detectors (TU Munich) Two 10cm x 10 cm sensors (P-Type) arrived, Radiation hard 1 Megarad level – to be verified !!! Electronics designed by W.Koenig, partially produced, 2 versions will be tested at Munich: - discreet version, TRB based system Robert Münzer - nXyter version: Rafal Lalik

32 Di-electrons from π − induced reactions at SIS18 M.Effenberger et al. nucl- th/ π − + A – inclusive ω measurement  - p bound  n  e + e - n; p e+e- < 300 MeV/c;  „at rest” Exclusive measurement large cross-section off-shell ρ/ω coupling to S 11 (1535) and D 13 (1550) M.Soyeur et al., nucl-th/  - p  (ω/ρ)n  e + e - n − selection of ρ and ω − η-> e + e -, π 0 π 0,... suppression by missing mass technique. Beam particle tracking is essential, in preparation cut on missing mass of e + e - (nutron );  e+e-  suppressed!