JStroth

Probing dense baryonic matter with time-like photons: 

Probing dense baryonic matter with time-like photons Dilepton spectroscopy from 1 to 40 AGeV at GSI and FAIR Joachim Stroth Univ. of Frankfurt

The physics case : 

The physics case What are the properties of dense nuclear matter? Its macroscopic properties depend on the microscopic structure!

The physics case: 

The physics case Probe the electromagnetic structure of (hot) and dense nuclear matter in the time-like region! What is the relevant excitation spectrum as the matter density increases? Where are the limits of hadronic existence? Additional self-energy terms due to meson-baryon coupling Partial restoration of chiral symmetry

Probing the interior of compressed matter: 

Probing the interior of compressed matter Low-mass vector mesons In-medium spectral functions

The HADES spectrometer: 

The HADES spectrometer Geometry Full azimuth , polar angles 18o - 85o Pair acceptance  0.35 About 80.000 detector channels Fast particle identification RICH CsI solid photo cathode, No 80, C4F10 radiator TOF (Scintillator rods) TOFino (Scintillator paddles) temporary solution, RPC in future Pre-Shower 18 pad chambers & lead converters Momentum measurement ILSE, super conducting toroid Br = 0.35 Tm MDC Multi-wire drift chamber, single cell resolution  100 mm 1 m

Experimental runs: 

Experimental runs November 2001: commissioning run target = 5% C+C 2 AGeV LVL1 triggered events (Mch.>3) : 45 Mevents C+C 1 AGeV LVL1 trigger : 7.3 Mevents full coverage with inner MDC chambers (Dp/p  10% at 0.7 GeV/c) November 2002: C+C 2 AGeV, commissioning and physics runs target= 2 x 2.5%, 56% LVL1 trigger + 44% LVL2 trigger 220 Mevents 6 outer drift chambers (MDC) in 4 sectors October 2003: p+p commissioning run (1 GeV, 2 GeV) full coverage with outer MDC III (4 MDC IV) (Dp/p  1.5 % at 0.7 GeV/c) February 2004: p+p 2GeV production run target 5 cm l-H2 400 Mevents August 2004: C+C 1AGeV production run 3x1.5 % target, 56% LVL1 trigger + 44% LVL2 trigger 650 Mevents

Fast 2nd level trigger: 

Fast 2nd level trigger up to 20 kHz LVL1 Fast multiplicity trigger full event information digitised. on-line selection of electron candidates LVL2 triggered events are transported to mass storage Suppression 10 - 100

On-line off-line comparison: 

On-line off-line comparison Trigger condition used in November 2002 run: At least one good electron candidate Ring matched with META hit Data rate reduced by 92 % Pair enhancement by factor of  9 Single lepton efficiency of IPUs + matching  62% (pairs 82%) No bias on data

C+C @ 2 A GeV "Nov’02": 

C+C @ 2 A GeV "Nov’02" preliminary No Efficiency / Acceptance Correction Minimal tracking analysis No in-medium contributions in the simulation.

C+C @ 1 A GeV “Aug'04”: 

C+C @ 1 A GeV “Aug'04” All N+- B+- = 2*sqrt(N++*N--) S+- = N+- - B+- M [MeV/c2] Yield / 1 MeV/c2 very preliminary No Efficiency / Acceptance Correction

Meson-baryon coupling and in-medium spectral functions: 

Meson-baryon coupling and in-medium spectral functions Starting in 2006! Precision spectroscopy at nuclear ground state density Invariant mass resolution with outer tracking is 1 % in the vector meson mass region M. Effenberger, Giessen One possible scenario W.Schoen et al. Acta Phys.PolB27(1996)2959

Slide13: 

nuclear matter at high densities CBM experiment Facility for Antiproton and Ion Research FAIR Staged realization

The future of dielectron spectroscopy at FAIR: 

The future of dielectron spectroscopy at FAIR Heavy ion collisions at interaction rates of up to 107 Hz and beam energies from 2 to 40 GeV/u CBM Detector HADES E < 10 AGeV E > 10 AGeV Talk by Peter Senger on Wednesday

HADES acceptance at higher energies: 

HADES acceptance at higher energies Thermal Source Accepted Ycm Ycm Ycm Ycm C+C 2 AGeV C+C 8 AGeV 1 GeV/c 1 GeV/c J. Novotny, HADES collaboration meeting 2003 Electrons from: po-Dalitz, h-Dalitz, r, w (-Dalitz), f 40 % of geometrical cross section Simulation

HADES with beam from SIS100: 

HADES with beam from SIS100 Compared to 2 A GeV acceptance 40% lower yields 2 orders of magnitude higher Simulation

Experimental concept: 

Experimental concept Perform momentum measurement in a 1m3 volume with 1 T magnetic field. Possibly a flexible configuration to optimize performance for different physics cases.. Both options, electrons and muons are investigated. Detector configuration CBM experiment High quality tracking to identify "background" tracks (conversion, p0)

Dilepton spectroscopy at GSI and FAIR: 

Dilepton spectroscopy at GSI and FAIR Final C+C spectra 1 and 2 AGeV p, p, d, A on lH2, A A+A heavy collision systems 2005 2010 2015 time [year AC] Dilepton spectroscopy in A+A at 10-40 AGeV A+A medium up to 8-10 AGeV Systematic study of the microscopic properties of dense baryonic matter

The Collaboration: 

The Collaboration Cyprus University of Cyprus France Institut de Physique Nucléaire d'Orsay Czech Republic Nuclear Physics Institute, Rez Czech Academy of Sciences, Rez Germany GSI, Darmstadt FZR, Dresden Johann Wolfgang Goethe-Universität Frankfurt Justus Liebig Universität Giessen Technische Universität München Italy INFN Catania Università di Catania INFN Milano Università di Milano Poland Jagiellonian University of Cracow Russia LHE at JINR, Dubna Institute for Nuclear Research, Moscow MEPHI, Moscow ITEP, Moscow Spain University of Santiago de Compostela Universidad de Valencia-CSIC

The CBM Collaboration: 

The CBM Collaboration 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. 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 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

Lepton candidate selection: 

Lepton candidate selection Events with lepton multiplicity  1 in LVL1 triggered events: 1.2 % Require META and RICH signal (LVL2) + matching with fully reconstructed tracks cut on b

Signal to Background Nov02: 

Signal to Background Nov02 preliminary Ne+e- - CB CB S/B = <S/B> ~ 4:1 (M < 100 MeV/c2) <S/B> ~ 1:2 (M > 100 MeV/c2) inv. mass [MeV/c2] S/B data simulation C+C Nov ‘02

Dielectrons in CBM: 

Dielectrons in CBM R. Karabowicz, Kraków, CBM Collaboration Meeting

Experiments with pion beams: 

Experiments with pion beams in-beam tracking of pions pp and pA reactions