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Chiral05, February-17-2005, RIKEN. Further experimental search for strange nuclear systems Kbar Nuclear Clusters from QGP to QGB Quark-Gluon Plasma Quark-Gluon Bound System. T. Yamazaki (RIKEN)
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Chiral05, February-17-2005, RIKEN Further experimental search for strange nuclear systems Kbar Nuclear Clusters from QGP to QGB Quark-Gluon Plasma Quark-Gluon Bound System T. Yamazaki (RIKEN) Y. Akaishi (KEK), A. Dote (KEK), M. Iwasaki (RIKEN), T. Suzuki (Uni Tokyo), P. Kienle (IMEP, Vienna), K. Suzuki (TU, Munich), N. Herrmann (Heidelberg )
Unique features of kaonic nuclei* I=0 KbarN pair attraction * condensed nuclei Non-existing nuclei:Normal nuclei : strongly bound K- (narrow)weakly bound K- (broad) (pp)S=0,T=1, (pn)S=0,T=1d: (pn)S=1,T=0 (ppp)S=1/2, J=3/2-, T=3/2t: (pnn)J=1/2,T=1/2 (ppn)S=1/2,J=3/2-,T=3/2 ** condensed:large spin-orbit splitting: p3/2 lowered ** large internal nucleon energy: EN >>0 ** K- potential: very deep EK = E - EN <<0 --->> Relativistic correction: energy pushed down
_ Nuclear KNN bound states S = 0 T = 3/2 Unbound S = 1 T = 1/2 Above the L*+n threshold S = 0 T = 1/2 E = -48 MeV G= 61 MeV Strange dibaryon Iso-doublet K- (pn) S=0,T=1 Modified --->> ~ -90 MeV Observed (FINUDA) ~ -90 MeV?
KEK E471 Population mechanismRole of L1405 S1(3140) FINUDA Doorway continumm fragmentation pL1405 ppK- S0(3115)
Key issues Experimental signatures for high density? DECoulomb, DEls, decay particle correlation,… Formation channel vs Decay channel Invariant mass spectroscopy L + d, L + p + p Dibaryon system: (pp)T=1K-, (pn)T=1K- Double strangeness systems: ppK-K-, pppK-K-,.. Toward multi-strangeness high-density matter heavy-ion reactions QGB with K-:kaon condensation
E = ENucl shrunk: >>0 + EK deep
Nuclear Shrinkage ? LS splitting p1/2-p3/2 DELS ~ 60 MeV!! Coulomb displacement energy DEC (1,1) - (1,-1) = 0.1 MeV for NNNK- = 2.1 MeV for a normal charged sphere (A=3)
Calculated spectral shape (Akaishi) Tp = 1.5 GeV/c L* compound
Discovery of K-NNN Bound States at KEKM. Iwasaki et al. 2004 4He(stopped K-,p)K-pnn (T=1) Mc2 = 3117 MeV, G~20 MeV BK =190 MeV 4He(stopped K-,n)K-ppn (T=0,1) Mc2 = 3140 MeV, G ~ 20 MeV BK = 170 MeV p3/2-p1/2
Decay pattern from a dense system Strong momentum correlation in 3-body decay ppK- ---> p + L ---> p + S+ + p- pppK- ---> p + p + L
L d tK ~ tfreeze-out~ 10 fm/c
Search for K- clusters as residues in heavy-ion reactions • High-density medium accommodated in QGP fire balls • Deep self-trapping centers of K- produced in fire balls • Slightly delayed decay after the freeze-out: tK > tfreeze-out • Invariant-mass spectroscopy for decay fragments Single-K-ppK- ---> L + p ppnK- ---> L + d pppK- ---> L + p + p ppnnK----> L + t pppnK----> L + 3He Double-K-ppK-K----> L + L pppK-K----> L + L pppnK-K----> L + Ld
FOPI at GSI from Kutsche (PhD) 1999 Superb L identification
Invariant-mass spectroscopy in H. I. Reactions1.9 GeV/u Ni + NiMinv(d+L) = 3140(17) [ppnK-]T=0
ppK-K- fragment expected at 10 GeV/u c.m. L L Jaffe’s H di-baryon? uud-ubar-s-ubar-s-uud not uuddss ?
Results of extremely proton-rich kaonic nuclei ppppK- pppK-K- ppppK-K- pppK- ppppK- Proton total B.E. 96.7 MeV E(K) 96.7 MeV Γ 12.5 MeV Rrms 0.81 fm ρmax 9.2 ρ0 total B.E. 75.1 MeV E(K) 75.1 MeV Γ 161.8 MeV Rrms 0.92 fm ρmax 9.9 ρ0 added 3 fm 3 fm K- added K- added ppppK-K- pppK-K- total B.E. 217.3 MeV E(K) 108.7 MeV Γ 41.2 MeV Rrms 0.73 fm ρmax 14.1 ρ0 total B.E. 205.7 MeV E(K) 102.8 MeV Γ 51.9 MeV Rrms 0.65 fm ρmax 21.6 ρ0 Proton added 3 fm 3 fm tentative 3fm 3fm 3fm E(K) = 75.1 MeV [ 77 MeV ] ρmax = 5.09 ρ(α) [ 5.1 ρ(α) ] E(K) = 102.8 MeV [ 103 MeV ] ρmax = 11.12 ρ(α) [ 12.5 ρ(α) ] E(K) = 108.6 MeV [ 110 MeV ] ρ(0) = 7.24 ρ(α) [ 7.5 ρ(α) ]
3He(K-,K+)X @ 1.8 GeV/c AGS E836LLn: 3170X-pn: 3199pppK-K-: 3422L*L*n: 3752 3000 MeV LLn: 3170 X-pn: 3199 3400 pppK-K-: 3422 L*L*n: 3752 3800
Yield: Prediction by chemical equilibrium model: A. Andronic and P. Braun-Munzinger, priv.comm., 16/10/03 Observed Combinatorial background R = S/N = BR(Kppn -->Ld)YKppn /(YLYd) ~ 0.004 YL~ 0.15, Yd ~ 2 BR(Kppn->Ld) ~0.1(assumed) Thus, Observed : YKppn ~ 0.012 ppK-K- expected at 10 GeV/u cm Prediction: YKppn ~ 0.01
Schematic Spontaneously, dynamically organized high density matter without the aid of gravity! Strangeness at high nuclear densities Nuclear incompressibility isovercome by the Strong K--p attraction At high density K- matter [K- p] + [K- p] + …+ n +… may be more stable
Hadrons in Nuclear Matter [GeV] 1.6 1.5 - K/N=3/2 p =uud 1.4 av. - 1.3 K/N=1 1.2 - 1.1 K/N=1/2 1.0 0.9 0.8 - - K =us 0.7 0.6 r/r0 0.5 4 5 6 0 2 1 3 7 Implication of KEK exp: BKppn(obs) = 173 MeV BKpnn(obs) = 195 MeV --->> enhanced KN in medium by 14% Chiral symmetry restoration? Deeply bound p- --->> enhanced pN by 35% QCD phase transition MN < EKN < ML: no strong decay, but weak decay: --> Metastable: nsec EKN < MN: absolutely stable: Strangelet, strange star Kaon condensation
Quark-Gluon Bound System Energy contour?? Ground state energy?? Quark Condensate diagramKaonic Nuclei: High density, T=0; Quark Phase Nucleon radius: rN ~ 0.8 fm Nucleon volume: vN ~ 2.1 fm3 Nucleon density: rN = 1/vN ~ 0.47 fm-3~ 2.8 r0 Compaction factor: r0/rN~ 1/2.8 --> critical density K-p subar-uud no hard core ubar-u attraction
K- clusters Cold, dense µscopic nuclear systems a New Paradigm - QGB - so far untouched chiral symmetry restoration?quark-gluon phase? exotic nuclear dynamics, strange matter/star, kaon condensation,……
KEK E471 from 4He FINUDA from 7Li,… Monoenergetic protons at 510 MeV/c Tamura et al. Yield of 4LH 4He/7Li ~ 1/4 Yield of 4LHe 4He/7Li ~ 1/3 FINUDA Yield of 4LHe
Cos(Lp) < - 0.86 S0p Lp mp+ mp+ mK- = 2370 mp + mL = 2054 (K -, p, p) invariant mass
pppnK- ppnK- +2p+n pppK- ppppK-+2n +p ppppK- +2n 6BeK-+pnn 6BeK- +p+2n 9BK-
D2 bubble chamber experiment d + K- ---> ps + L1405 + p- “n” + K- ---> L1405 + p-
Evidence for ppK-(1976) decaying to p + S + p???!!! ps: high momentum componentMinv(Sp): distributedMissing mass of (K-,p-) ?Invariant mass of p + S + p ?
Proposed FOPI experiment (I)d + 4 GeV p ---> p + L* + K0 + p (~10 nb/sr) ( --> pL* + K0 + p ) --> ppK- + K0 + pmissing massppK---> p + Linvariant mass
L1405=L* cascade reaction in 4HeInitial p + “n” --> L* + K0 + pL* + “ppn” --> L*pp + n --> pppK- + n“nK0” + “ppn” --> ppnK0 + n (“Kaon Transfer”) pppK----> p + p + L (invariant mass)L* + “ppn” --> L*pn + p --> ppnK- + p“pK-” + “ppn” --> ppnK- + p (“Kaon Transfer”) ppnK----> d + L (invariant mass) L* + “pn” --> L*p + n --> ppK- + nppK----> p + L (invariant mass) Small momentum transfer (soft landing) pppK- momentum (MeV/c) L1405 kinetic energy (MeV)