Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3...

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Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 ) The nuclear equation-of-state In medium properties of strange mesons Towards highest baryon densities (3-10 ρ 0 ) Exploring the phases of QCD matter Peter Senger (GSI) ernational Symposium on Heavy-Ion Physics, April 2-6, 2006, Frankfur

Transcript of Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3...

Page 1: Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 )  The nuclear equation-of-state  In medium.

Strange particles and neutron stars -experiments at GSI

Outline:

Probing dense baryonic matter (1-3 ρ0) The nuclear equation-of-state In medium properties of strange mesons

Towards highest baryon densities (3-10 ρ0) Exploring the phases of QCD matter

Peter Senger (GSI)

International Symposium on Heavy-Ion Physics, April 2-6, 2006, Frankfurt

Page 2: Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 )  The nuclear equation-of-state  In medium.

Strongly interacting matter in neutron stars

F. Weber J.Phys. G27 (2001) 465

nucleon star: kaon condensate

“Strangeness" of dense matter ?In-medium properties of hadrons ?Nuclear matter equation of state ?

Deconfinement at high baryon densities ?

color superconductor ?

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Kaon production in Au+Au collisions at 1 AGeV

K+ mesons probe high densities

udsn

du

udd

su

K+

udu

uu

uds

su

p

K-K-

absorption

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Idea: K+ yield baryon density ρ compressibility κ

Au+Au at 1 AGeV (RBUU): soft eos ρmax 2.9 ρ0 K+ yield uphard eos ρmax 2.4 ρ0 K+ yield down

but: in C+C no influence of eos on K+ yield !

Probing the nuclear equation-of-state at high density by K+ meson production in C+C and Au+Au collisions

C. Sturm et al., Phys. Rev. Lett. 86 (2001) 39

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C. Fuchs et al., Phys.Rev.Lett. 86 (2001) 1974

QMD transport calculations

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The compressibility of nuclear matterExperiment: C. Sturm et al., Phys. Rev. Lett. 86 (2001) 39Theory: QMD C. Fuchs et al., Phys. Rev. Lett. 86 (2001) 1974 IQMD Ch. Hartnack, J. Aichelin, J. Phys. G 28 (2002) 1649

soft equation-of-state:= 200 MeV

Figure by C. Fuchs

Page 8: Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 )  The nuclear equation-of-state  In medium.

K mesons in dense matterG.E Brown, C.H. Lee, M. Rho, V. Thorsson, Nucl. Phys. A 567 (1994) 937 T. Waas, N. Kaiser, W. Weise, Phys. Lett. B 379 (1996) 34

J. Schaffner-Bielich, J. Bondorf, I. Mishustin ,Nucl. Phys. A 625 (1997)

M. Lutz, C. Korpa, Nucl. Phys. A 700 (2002) 309 self-consistent coupled channel calculation (s,p,d waves)

In-medium spectral functionsof K-, (1405) and (1385)

(1405)

K- K-

N-1

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In-medium modifications of K+ mesons

Data: M. Menzel et al., KaoS Collab., Phys. Lett. B 495 (2000) 26 K. Wisniewski et al., FOPI Collab., Eur. Phys. J A 9 (2000) 515

Figure by C. Fuchs

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Data: Y. Shin et al., Phys. Rev. Lett. 81 (1998) 1576 F. Uhlig et al., Phys.Rev.Lett. 95 (2005) 012301

Theory: A. Larionov, U. Mosel, nucl-th/0504023

Evidence for repulsive K+N interaction !

K+ azimuthal emission pattern from A+A collisions

Page 11: Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 )  The nuclear equation-of-state  In medium.

F. Uhlig et al., Phys. Rev. Lett. 95 (2005) 012301

Ni+Ni at 1.93 AGeV: π, K+ and K- azimuthal distributions

3.8 fm < b < 6.4 fm 0.4 < y/ybeam <0.6 0.2 GeV < p┴< 0.8 GeV IQMD Calculation:

C. Hartnack et al.

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dN(φ)/φ 1 + 2v1cos(φ) + 2v2cos(2φ) + ...

Au+Au 1.5 AGeV semi-central collisions (b > 6.4 fm)K+ and K- azimuthal angular distributions

M. Płoskon, PhD Thesis 2005

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dN(φ)/φ 1 + 2v1cos(φ) + 2v2cos(2φ) + ...

Elliptic flow of K+ and K- mesons:Comparison to off-shell transport calculations

and in-medium spectral functionsData: M. Płoskon, PhD Thesis, Univ. Frankfurt 2005Off-shell transport calculations: 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

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The Kaon Spectrometer at SIS (1991 – 2002)

CollaborationGSI Darmstadt: P. Koczoń, F. Laue, M. Płoskon, E. Schwab, P Senger, C. Sturm

TU Darmstadt: A. Förster, S. Lang, H. Oeschler, A. Schmah, F. Uhlig

Univ. Frankfurt: Y. Shin, T. Schuck, H. Ströbele

Univ. Marburg: I. Böttcher, B. Kohlmeyer, M. Menzel

Univ. Kraków: M. Dębowski, G. Surówka, W. Waluś

FZ Rossendorf: F. Dohrmann, E. Grosse, L. Naumann, W. Scheinast, W. Wagner

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Towards higher baryonic densities

Ch. Fuchs, Tübingen

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Baryon density in central cell (Au+Au, b=0 fm):QGSM: Cascade, hadrons + resonances + strings

Transport calculations: baryon and energy densities

C. Fuchs, V. Toneev

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“Trajectories” from UrQMD

H. Stöcker nucl-th/0506013

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“Trajectories” from 3 fluid hydrodynamics

Hadron gas EOS:Y. Ivanov, V. Russkikh, V.Toneev nucl-th/0503088

early phase (first 2 fm/c) not inthermodynamic equilibrium !

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Intriguing observations by NA49 @ CERN-SPS

coexistence phase

hadronsQGP

critical point

next steps:confirmation of NA49 → Low energy run at RHIC ?comprehensive experimental study → CBM @ FAIR

?

Pb+Pb

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Diagnostic probes of compressed baryonic matter

U+U 23 AGeV

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Compressed Baryonic Matter: physics topics and observables

Search for chiral symmetry restoration at high B

in-medium modifications of hadrons

Observables: , , e+e- , open charm, .....

Search for a deconfined phase at high B enhanced strangeness production ? Observables: K, , , , anomalous charmonium suppression ? Observables: charmonium (J/ψ, ψ'), open charm (D0, D)

Probing the equation-of-state at high B

Observables: collective flow of hadrons, particle production at threshold energies (open charm)

Search for the 1. order phase transition & the critical endpoint Observable: event-by-event fluctuations (K/π, pT, ...)

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Observables:Penetrating probes: , , , J/ → e+e- (μ+μ-)Strangeness: K, , , , , Open charm: Do, D, Ds, c,

global features: collective flow, fluctuations, ..., exotica

Experimental program of CBM:

Systematic investigations:A+A collisions from 8 to 45 (35) AGeV, Z/A=0.5 (0.4) p+A collisions from 8 to 90 GeVp+p collisions from 8 to 90 GeVBeam energies up to 8 AGeV: HADES

Large integrated luminosity:High beam intensity and duty cycle,Available for several month per year

Detector requirementsLarge geometrical acceptance (azimuthal symmetry !)good hadron and electron identificationexcellent vertex resolutionhigh rate capability of detectors, FEE and DAQ

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SIS18 SIS100/

300

Meson production in central Au+Au collisionsW. Cassing, E. Bratkovskaya, A. Sibirtsev, Nucl. Phys. A 691 (2001) 745

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Radiation hard Silicon (pixel/strip) Tracking System in a magnetic dipole field

Electron detectors: RICH & TRD & ECAL: pion suppression better 104

Hadron identification: TOF-RPC

Measurement of photons, π, η, and muons: electromagn. calorimeter (ECAL)

High speed data acquisition and trigger system

The CBM Experiment

Silicon Tracking System (STS)

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Experimental challenges

107 Au+Au reactions/sec (beam intensities up to 109 ions/sec, 1 % interaction target) determination of (displaced) vertices with high resolution ( 50 m) identification of electrons and hadrons

Central Au+Au collision at 25 AGeV:URQMD + GEANT4

160 p, 400 -, 400 +, 44 K+, 13 K-,....

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HADES2 – 8 AGeV

CBM8 – 45 AGeV

and outlook

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CBM Collaboration : 40 institutions, > 350 MembersCroatia: RBI, Zagreb

China:Wuhan Univ.Hefei Univ.

Cyprus: Nikosia Univ.  

Czech Republic:CAS, RezTechn. Univ. Prague

France: IReS Strasbourg

Hungaria:KFKI BudapestEötvös Univ. Budapest

India:VECC Kolkata

   

Romania: NIPNE Bucharest

Russia:IHEP ProtvinoINR TroitzkITEP MoscowKRI, St. PetersburgKurchatov Inst., MoscowLHE, JINR DubnaLPP, JINR DubnaLIT, JINR DubnaMEPHI MoscowObninsk State Univ.PNPI GatchinaSINP, Moscow State Univ. St. Petersburg Polytec. U.

Ukraine: Shevshenko Univ. , Kiev

Korea:Korea Univ. SeoulPusan National Univ.

Norway:Univ. Bergen

Germany: Univ. Heidelberg, Phys. Inst.Univ. HD, Kirchhoff Inst. Univ. FrankfurtUniv. KaiserslauternUniv. Mannheim Univ. MünsterFZ RossendorfGSI Darmstadt

Poland:Krakow Univ.Warsaw Univ.Silesia Univ. Katowice 

Portugal: LIP Coimbra

Page 29: Strange particles and neutron stars - experiments at GSI Outline: Probing dense baryonic matter (1-3 ρ 0 )  The nuclear equation-of-state  In medium.

SummaryProbing dense baryonic matter (1-3 ρ0):

Excitation function of K+ production in A+A collisions: The nuclear matter equation-of-state is soft ( K 200 MeV) Yield and elliptic flow of K+ mesons: The in-medium potential of K+ mesons is repulsive Yield and elliptic flow of K- mesons: Quantitative interpretation of data requires off-shell transport calculations and in-medium spectral functions

Towards highest baryon densities (3-10 ρ0):

Search for:• first order phase transition• critical endpoint • chiral symmetry restoration

Probes: strangeness, charm, vector mesons, flow,correlations, fluctuations, .....

Comprehensive studies with CBM @FAIRComplementary to RHIC and ALICE

and outlook

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SIS100/ 300

Theoretical prediction of meson production in central Au+Au collisions

Hadron String Dynamics transport calculation W. Cassing, E. Bratkovskaya, A. Sibirtsev, Nucl. Phys. A 691 (2001) 745

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Off-shell transport calculations

off-shell HSD: W. Cassing et al., NPA 727 (2003) 59

0

2

4

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0

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A(s

) [M

eV-1]

p=0 MeV/c

A(s

) [M

eV-1]

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p=150 MeV/c

0.2 0.4 0.6 0.80

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s1/2

[GeV]

p=300 MeV/c

s1/2

[GeV]

0.2 0.4 0.6 0.8

20

1.50

0

0.50

p=500 MeV/c

L. Tolos et al., NPA 690 (2001) 547coupled channel G-Matrix approach:K- spectral functions