HADRONIC SIGNATURES OF DECONFINEMENT STRANGENESS s AND ENTROPY S Quark Con¯nement and the Hadron Spectrum, Cagliari, Italy, September 21, 2004 [ I] How and why: search for decon¯nement in RHI Collisions [ II] Strangeness, entropy and resonances probes of decon¯nement p5 [III] Sudden hadronization and quark dynamics p10 [IV] Statistical hadronization: methods, results, insights p18 [V] Strangeness, entropy and QGP p26 Supported by a grant from the U.S. Department of Energy, DE-FG02-04ER41318 In collaboration with Jean Letessier, Paris and Giorgio Torrieri, Toronto Johann Rafelski Department of Physics University of Arizona TUCSON, AZ, USA 1 J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 2 Particle/nuclear era in the evolution of the Universe Visible Matter Density [g cm−3 ] 1027 1015 103 10−9 1 TeV LHC 1016 quarks combine RHIC atoms antimatter form disappears 1 GeV photons 1013 neutrinos decouple SPS decouple nuclear reactions: light nuclei formed 1 MeV era of 1010 galaxies and stars 7 Particle energy 1 keV 10 Temperature [K] OBSERVATIONAL COSMOLOGY 1 eV 104 PARTICLE/NUCLEAR ASTROPHYSICS 10 10−12 10−6 1 106 1012 1018 day year ky My today Time [s] J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 3 THE EARLY DECONFINED UNIVERSE IN THE LABORATORY Micro-Bang 135 81 Pb QGP Pb Au Au 115 47 363 353 Big-Bang Micro-Bang τ −∼ 10 µ s τ −∼ 4 10-23 s ∼ -10 ∼ NB / N − 10 NB / N − 0.1 Order of Magnitude ENERGY density ² 1{5GeV/fm3 = 1:8{9 1015g/cc ' Latent vacuum heat B 0:1{0.4GeV/fm3 (166{234MeV)4 ' ' 1 30 PRESSURE P = 3² = 0:52 10 barn Reinhard Stock NA35 1986: S{Ag at 200AGeV TEMPERATURE T ; T 300{250, 175{145 MeV; 300MeV 3.5 1012K 0 f ' J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 4 BROOKHAVEN NATIONAL LABORATORY 12:00 o’clock PHOBOS BRAHMS 10:00 o’clock 2:00 o’clock RHIC PHENIX 8:00 o’clock STAR 4:00 o’clock 6:00 o’clock Design Parameters: Beam Energy = 100 GeV/u U-line 9 GeV/u No. Bunches = 57 High Int. Proton Source BAF (NASA) µ g-2 9 Q = +79 No. Ions /Bunch = 1×10 LI NAC T = 10 hours BOOSTER store L = 2 × 1026 cm-2 sec -1 Pol. Proton Source ave AGS HEP/NP 1 MeV/u Q = +32 TANDEMS RHIC: Relativistic Heavy Ion Collider 20 < psNN < 200 A-A J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 5 Decon¯nement We aim to verify experimentally the theory paradigm: the QCD Vacuum structure is the origin of quark con¯nement. What/where is decon¯nement? A domain of (space, time) much larger than normal hadron size in which color- charged quarks and gluons are propagating, constrained by external `frozen vac- uum' which abhors color. We expect a pronounced boundary in temperature and density between con¯ned and decon¯ned phases of matter: phase diagram. Decon¯nement expected at both high temperature and at high matter density. In a ¯nite size system expect in general a `transformation', not a sharp boundary. What we need as background knowledge: 1) Hot QCD in equilibrium (quark-gluon plasm, QGP) from QCD-lattice, 2) Understanding how to adapt QGP to the non-equilibrium heavy ion reactions, 3) Understanding of hadronization dynamics and ¯nal particle yields, 4) Identify sensitive (hadronic and other) signatures of decon¯nement beware: ¯nal particles always hadrons NOT A SINGLE SMOKING GUN type observation, NOT a`new particle'. J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 6 Hadronic observables: STRANGENESS s AND ENTROPY S Stable matter is made of only up and down quarks, strange flavor is always almost all newly made. In the QGP hadrons are dissolved into an entropy rich partonic liquid. Ω Once entropy has been created in the breaking of color bonds, it u s s s u u g s cannot decrease, appears in hadron u d d d multiplicity. s s s s d g d g TWO STEP MECHANISM of (strange) s g u g u u s g hadron formation from QGP: s s d u u d g s d 1. GG ss¹ in QG-plasma d d ! s g g u s s 2. hadronization of pre-formed s; s¹ u d d g u quarks s s u RESULT: Excess of strangeness and Ξ even more of complex rarely pro- duced multi strange (anti)particles from QGP enabled by coalescence of s; s¹ quarks made earlier in QCD based microscopic reactions. IN REVERSE: strangeness enhancement indicates presence of glu- ons (speci¯c for decon¯nement) as a new strangeness producing source, and strange antibaryon enhancement indicated coalescence which is a signature of quark mobility in the source volume. J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 7 Hadronic observables: Resonances Statistical Hadronization Hypothesis: particle e production (both (relative) yields and spectra) can be described by maximizing the accessible phase space, This is the Fermi-Hagedorn model. TEST AND USE OF STATISTICAL HADRONIZATION MODEL Particle yields with same valance quark content are in relative chemical equilibrium, e.g. the relative yield of ¢(1230)=N as of K¤=K, §¤(1385)=¤, etc, is controlled by chemical freeze-out temperature T : 1.0 T=140 MeV 0.9 3=2 m =T T=160 MeV N ¤ g¤(m¤T ) e¡ ¤ π T=180 MeV = 0.8 3=2 m=T Λ N g(mT ) e¡ 0.7 p Resonances decay rapidly into 0.6 K `stable' hadrons and domi- 0.5 Ξ nate the yield of most stable 0.4 hadronic particles. 0.3 * Resonance contribution K Resonances test ¯rst statisti- 0.2 φ cal hadronization principle and Ω~0 0.1 beyond, characterize the dy- 0.0 0.0 0.5 1.0 1.5 namics of QGP hadronization. Mass J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 8 OBSERVABLE RESONANCE YIELDS Invariant mass method: construct invariant mass from decay prod- ucts: 2 2 2 2 2 2 2 M = ( ma + p~a + mb + p~b + : : :) (p~a + p~b + : : :) q ¡ If one of decay prop ducts rescatter the reconstruction not assured. Apparent `suppression' of resonance production. Strongly interacting matter essentially non-transparent. Simplest model: If resonance decays within matter, resonance disappears from view. Implementation Attenuation of yield N ¤ seen in channel involving ¯nal Decay state N ¤ D + : : :; ¡ is N ¤ in matter width, ! N ¤(t = 0) given by statistical hadronization, D(t = 0) = 0: 3 dN ¤ dD R0 = ¡N ¤ + R; = ¡N ¤ D σ v ½ dt ¡ dt ¡ h Dj Dji j µR + v t¶ Xj 0 c In the loss term, the last factor dilutes the density of scattering matter by collective expansion with velocity vc, here shown in 3D. Integrate to time t = ¿, the time spend in the opaque matter. This time can be interpreted as the time it takes the particle N ¤ to INEL escape into free space. Regeneration term R σDi vDi ½i much smaller since real production required, i j/.h i f g ¿ f g J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 9 TWO resonance ratios combined natural widths spread ¡§ = 150 MeV 0 ¤ 10 NA49 sudden 0.60 NA49 STAR STAR Γ =150 MeV Γ = Σ∗ Κ∗ 50 MeV Γ K*=50 MeV ) Γ = ) Σ∗ 35 MeV Λ T=200 Λ 0.40 /(all −1 /(all Thermally produced τ=1 10 T=175 fm T=200 MeV T=150 (1385) (1385) ∗ ∗ Σ T=100 MeV T=125 Σ 0.20 τ=2 fm T=100 MeV τ= τ=20 fm 3 fm ... −2 10 −3 −2 −1 0 0.00 10 10 10 10 0.00 0.20 0.40 0.60 * + * + K (892)/(all K ) K (892)/(all K ) Dependence of the combined §¤/(all ¤) with K¤(892)=(all K) signals on the chemical freeze-out temperature and HG phase lifetime. Even the ¯rst rough measurement of K¤=K indicates that there is no long lived hadron phase. In matter widening makes this conclusion stronger. J.R., J. Letessier and G. Torrieri, Phys. Rev. C64, 054907 (2001); C65, 069902(E) (2002) J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 10 We are lead to: Sudden Hadronization of QGP Other evidence for sudden hadronization - hadron emission directly into free space: CERN SPS Experiments since 1991 (WA85, WA97, NA57, NA49) see identical shape of m spectra of strange baryons and antibaryons, obtained in central reactions? at CM rapidity, also observed at RHIC. Interpretation: Common matter-antimatter formation mechanism, little reannihilation in sequel evolution. Antibaryon appears to be DIRECTLY EMITTED by a quark source into vacuum. Fast hadronization con¯rmed further by HBT particle correlation analysis, which yields a nearly energy independent size of hadron ¯reball with short lifespan of pion production. J. Rafelski, Arizona Hadronic Signatures of Decon¯nement Con¯nement 6, Italy, September 21, 2004, page 11 High m matter{antimatter slope universality: SPS ? Pb ) WA97 T [MeV] 4 2 ? c 10 -2 T ¤ 289 3 10 § ¤ T 287 4 (GeV 1 T × Λ § -1 10 10 ×10 Λ T ¥ 286 9 -2 § Ξ 10 Ξ+ T ¥ 284 17 dN/dm -3 § 10T ­+­ -4 -1 - 1/m × Ω T 251 19 10 10 § -5 ×10-2 Ω+ 10 1 2 3 4 2 ¤ within 1% of ¤ mT (GeV/c ) J.