Resonances Do Not Equilibrate Needed For: the Understanding Of

Resonances do not Equilibrate needed for: the Understanding of QGP Bulk Hadronization Inga Kouznetsova, Jean Letessier, and Johann Rafelski Krak´ow, WPCF08, September 12, 2008

1) Introduction: strangeness signature of QGP;

2) Recombinant hadronization with γq and SHARE; 3) NA49 data, quality of ﬁts, statistical parameters; critical pressure 4) Resonances evolve beyond particle freeze-out: description of 1+2 3 reactions ↔ 5) Study of Σ(1385) enhancement and Λ(1520) suppression.

Presented by Johann Rafelski University of Arizona, TUCSON and Sektion Physik der LMU, MUNCHEN

Supported by: the U.S. Department of Energy, DE-FG02-04ER41318 and by LMU Excellent. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 2 Strangeness in QGP Proposal to study strange particle production as probe of quark-gluon plasma and as signature of phase tran- sition between nuclear and quark matter appears in the CERN Theory preprint CERN-TH-2969 of Oc- tober 1980 (Rafelski & Hagedorn). Published in “Statistical Mechanics of Quarks and Hadrons” Else- vier 1981. Total strangeness and strange antibaryon enhancement signatures of deconﬁned QGP phase.

Chemical equilibrium in QGP presumed. A point of considerable later research eﬀort. By 1982 I argue in quantitative way that QGP equilibrium means strange hadron excess over equilibrium after hadronization. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 3

Bulk Hadronization by Recombination of Quarks

1. GG ss¯ (thermal gluons collide) → Ω GG cc¯ (initial parton collision) → ¯ u s s s GG bb (initial parton collision) u u → g s gluon dominated reactions u d d d s s s s d g d 2. RECOMBINATION of pre-formed g s g u g u ¯ u s g s, s,¯ c, c,¯ b, b quarks s s d u u d g s d Formation of complex rarely produced d d multi flavor (exotic) (anti)particles s g g u s s enabled by coalescence between u d d g u s, s,¯ c, c,¯ b, ¯b quarks made in different microscopic reactions; this is signature s s u of quark mobility and independent Ξ action, thus of deconfinement. More- over, strangeness enhancement = gluon mobility. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 4

The recombinant hadronization mechanism is visible in: 2.5 Λ Baryon to Meson Ratio 0 AuAu200 (STAR) AuAu130 (STAR) KS p Ratios Λ/KS and p/π in Au-Au com- 2 - AuAu200 (PHENIX) pp200 (STAR) π pared to pp collisions as a function of 1.5 p . The large ratio at the intermediate ⊥ p region: evidence that particle for- 1 ⊥

Baryon/Meson mation (at RHIC) is distinctly diﬀerent from fragmentation processes for the el- 0.5 + ementary e e− and pp collisions.

0 0 2 4

pT [GeV/c] To describe recombinant yields: nonequilibrium parameters needed

• γq (γs,γc,...): u,d (s, c, . . .) quark phase space yield, absolute chemical equilib- n rium: γi 1 γ3 → baryons q γs 2 mesons ∝ γq · γq

• γs/γq shifts the yield of strange vs non-strange hadrons: Λ(¯ud¯s¯) γ K+(us¯) γ φ γ2 Ω(sss) γ2 s , s , s , s , ¯ + ¯ 2 2 p¯(¯uu¯d) ∝ γq π (ud) ∝ γq h ∝ γq Λ(sud) ∝ γq Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 5 Statistical Hadronization fits of hadron yields Full analysis of experimental hadron yield results requires a signifi- cant book-keeping and fitting effort in order to allow for resonances, particle widths, full decay trees, isospin multiplet sub-states.

Kraków-Tucson (and SHARE 2 Montreal) collaboration produced a public package SHARE Statistical Hadronization with Resonances which is available e.g. at http://www.physics.arizona.edu/˜torrieri/SHARE/share.html Lead author: Giorgio Torrieri, W. Broniowski, W. Florkowski, J. Letessier, et al nucl–th/0404083 Comp. Phys. Com. 167, 229 (2005) SHARE 2.2 with flexible weak decays, fluctuations and chemical flexibility now on line. Involves S.Y. Jeon, Montreal, allows fluctuations and better handling of WI corrections. Comp. Phys. Com. 175, 635 (2006) nucl-th/0603026

Aside of particle yields, also PHYSICAL PROPERTIES of the source are available, both in SHARE and ONLINE.

DATA: Energy dependence of geometrically most central interac- tions (5–7% trigger), use particle yields Ni or/and at RHIC dN/dy Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 6

E[AGeV] 11.6 20 30 40 80 158 √sNN [GeV] 4.84 6.26 7.61 8.76 12.32 17.27 yCM 1.6 1.88 2.08 2.22 2.57 2.91

N4π centrality most central 7% 7% 7% 7% 5% + R = p/π , NW R =1.23 0.13 349 6 349 6 349 6 349 6 362 6 ± ± ± ± ± ± s s/s¯ +¯s 0 0.05 0 0.05 0 0.05 0 0.05 0 0.05 0 0.05 − ± ± ± ± ± ± Q/b 0.39 0.02 0.394 0.02 0.394 0.02 0.394 0.02 0.394 0.02 0.39 0.02 ± ± ± ± ± ± π+ 133.7 9.9 184.5 13.6 239 17.7 293 18 446 27 619 48 + ± ± ± ± ± ± R = π−/π , π− R =1.23 0.07 217.5 15.6 275 19.7 322 19 474 28 639 48 + + ± ± ± ± ± ± R = K /K−,K R =5.23 0.5 40 2.8 55.3 4.4 59.1 4.9 76.9 6 103 10 ± ± ± ± ± ± K− 3.76 0.47 10.4 0.62 16.1 1 19.2 1.5 32.4 2.2 51.9 4.9 ± ± ± ± ± ± R = φ/K+, φ R =0.025 0.006 1.91 0.45 1.65 0.5 2.5 0.25 4.58 0.2 7.6 1.1 ± ± ± ± ± ± Λ 18.1 1.9 28 1.5 41.9 6.1 43.0 5.3 44.7 6.0 44.9 8.9 ± ± ± ± ± ± Λ 0.017 0.005 0.16 0.03 0.50 0.04 0.66 0.1 2.02 0.45 3.68 0.55 ± ± ± ± ± ± Ξ− 1.5 0.13 2.48 0.19 2.41 0.39 3.8 0.260 4.5 0.20 + ± ± ± ± ± Ξ 0.12 0.06 0.13 0.04 0.58 0.13 0.83 0.04 ± ± ± ± Ω + Ω pre 2008 data 0.14 0.07 KS ± 81 4 3 ± V [fm ] 3596 331 4519 261 1894 409 1879 183 2102 53 3004 1 ± ± ± ± ± ± T [MeV] 157.8 0.7 153.4 1.6 123.5 3 129.5 3.4 136.4 0.1 136.4 0.1 ± ± ± ± ± ± λq 5.23 0.07 3.49 0.08 2.82 0.08 2.42 0.10 1.94 0.01 1.74 0.02 ± ± ± ± ± ± λs 1.657∗ 1.41∗ 1.36∗ 1.30∗ 1.22∗ 1.16∗

γq 0.335 0.006 0.48 0.05 1.66 0.10 1.64 0.04 1.64 0.01 1.64 0.001 ± ± ± ± ± ± γs 0.190 0.009 0.38 0.05 1.84 0.32 1.54 0.15 1.54 0.05 1.61 0.02 ± ± ± ± ± ± λI3 0.877 0.116 0.863 0.08 0.939 0.023 0.951 0.008 0.973 0.002 0.975 0.004 ± ± ± ± ± ± µB [MeV] 783 576 384 344 271 227 µS [MeV] 188 139 90.4 80.8 63.1 55.9 Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 7

E[AGeV] 11.6 20 30 40 80 158 √sNN [GeV] 4.84 6.26 7.61 8.76 12.32 17.27 yCM 1.6 1.88 2.08 2.22 2.57 2.91

N4π centrality most central 7% 7% 7% 7% 5% + R = p/π , NW R =1.23 0.13 349 6 349 6 349 6 349 6 362 6 ± ± ± ± ± ± s s/s¯ +¯s 0 0.05 0 0.05 0 0.05 0 0.05 0 0.05 0 0.05 − ± ± ± ± ± ± Q/b 0.39 0.02 0.394 0.02 0.394 0.02 0.394 0.02 0.394 0.02 0.39 0.02 ± ± ± ± ± ± π+ 133.7 9.9 190.0 10.0 241 13 293 18 446 27 619 48 + ± ± ± ± ± ± R = π− /π , π− R =1.23 0.07 221.0 12.0 274 15 322 19 474 28 639 48 + + ± ± ± ± ± ± R = K /K−, K R =5.23 0.5 40.7 2.9 52.9 4.2 56.1 4.9 73.4 6 103 10 ± ± ± ± ± ± K− 3.76 0.47 10.3 0.3 16 0.6 19.2 1.5 32.4 2.2 51.9 4.9 ± ± ± ± ± ± R = φ/K+, φ R =0.025 0.006 1.89 0.53 1.84 0.51 2.55 0.36 4.04 0.5 8.46 0.71 ± ± ± ± ± ± Λ 18.1 1.9 27.1 2.4 36.9 3.6 43.1 4.7 50.1 10 44.9 8.9 ± ± ± ± ± ± Λ 0.017 0.005 0.16 0.05 0.39 0.06 0.68 0.1 1.82 0.36 3.68 0.55 ± ± ± ± ± ± Ξ− 1.5 0.3 2.42 0.48 2.96 0.56 3.8 0.87 4.5 0.20 + ± ± ± ± ± Ξ 0.12 0.05 0.13 0.03 0.58 0.19 0.83 0.04 ± ± ± ± Ω + Ω with 2008 data 0.14 0.07 KS ± 81 4 3 ± V [fm ] 3649 331 4775 261 2229 340 1595 383 2135 235 3055 454 ± ± ± ± ± ± T [MeV] 153.5 0.8 151.7 2.8 123.8 3 130.9 4.4 135.2 0.01 136.0 0.01 ± ± ± ± ± ± λq 5.21 0.07 3.53 0.09 2.86 0.09 2.42 0.09 1.98 0.07 1.744 0.02 ± ± ± ± ± ± λs 1.565∗ 1.39 0.05 1.45 0.05 1.34 0.06 1.25 0.18 1.155 0.03 ± ± ± ± ± γq 0.366 0.008 0.49 0.03 1.54 0.37 1.66 0.14 1.65 0.01 1.64 0.01 ± ± ± ± ± ± γs 0.216 0.009 0.40 0.03 1.61 0.07 1.62 0.25 1.52 0.06 1.63 0.02 ± ± ± ± ± ± λI3 0.875 0.166 0.877 0.05 0.935 0.013 0.960 0.027 0.973 0.014 0.975 0.005 ± ± ± ± ± ± µB [MeV] 759 574 390 347 276 227 µS [MeV] 180 141 83.7 77.6 62.0 56.0 Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 8

How good is the fit? χ2/dof and confidence level P[%] as function of γq. For lowest two energies (AGS/SPS): small γq < 1 preferred, for other energies γ emπ/2T , maximum of q → entropy. If only one reaction energy is con- sidered one may think γq = 1 is useful. But evaluated as function of γq for several reaction energies a different picture arises. NOTE: All results obtained with latest SHARE 2.2 and updated NA49-2008 DATA. We do not impose exact strangeness con- servation, but require that strangeness bal- ances at a level of precision found in indi- vidual strange hadron data: s¯ s − 0 0.05. s¯ + s ≃ ± Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 9

Statistical parameter for NA49-SPS The lines guide the eye. Reduced T at high energy (by 15 MeV from 158 MeV), we think is due to fast expansion. Enhanced T at low reaction energy: we think there is valance (massive) quark phase, this keeps number of particles down and thus T up .

The value of γq rises to maximum pos- sible where pion condensate arises. The

rise of γs/γq suggests that at a low reaction energy strangeness increases and catches up with entropy growth. This also suggests that a deconﬁned valon (massive constituent quark, m 330 q ≃ MeV, m 500 MeV melts and a pQCD s ≃ phase arises. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 10

The most challenging experimental result: K+/π+ HORN

Lines connect fit points to guide the eye. Solid line: we explain the ‘horn’ since a fit with γi has build-in capability to dilute the K+/π+ yield e.g by a (relative) fast growth of d¯ formation, in the valon picture, the heavy constituent quarks melt, the yield of d¯ rapidly rises. Dotted line: no deconfinement, chemically equilibrated (well “cooked”) hadrons do not describe the K+/π+ yield. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 11 Condition of hadronization: CRITICAL PRESSURE

Physical properties of bulk matter at hadronization show a change, from a low density and low pressure system at low √s to a highly compressed phase just above this. Note that hadronization is characterized by a value of P 78.5 MeV/fm3. Energy per hadron proposed by K. Redlich as condition of hadroniza-≃ tion is also practically constant at high reaction energies. However, this is not the case for ﬁnite baryon density. This variable expresses the critical pressure hadronization condition, when pressure is dominated by pions. Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 12

PREDICTIONS: AGS/SPS particle yields pre 2008 NA49 data, AGS: SHARE 1.2 : E [A GeV] 11.6 20 30 40 80 158 √sNN [GeV] 4.84 6.26 7.61 8.76 12.32 17.27 yCM 1.6 1.88 2.08 2.22 2.57 2.91

N4π/ centr. m.c. 7% 7% 7% 7% 5% b B B 375.6 347.9 349.2 349.9 350.3 362.0 s ≡s/s¯ −+¯s 0 -0.092 -0.085 -0.056 -0.029 -0.062 − π+ 135.2 181.5 238.7 290.0 424.5 585.2 π− 162.1 218.9 278.1 326.0 461.3 643.9 K+ 17.2 39.4 55.2 56.7 77.1 109.7 K− 3.58 10.4 15.7 19.6 35.1 54.1 KS 10.7 25.5 35.5 37.9 55.1 80.2 φ 0.46 1.86 2.28 2.57 4.63 7.25 p 174.6 161.6 166.2 138.8 138.8 144.3 p¯ 0.021 0.213 0.68 0.76 2.78 5.46 Λ 18.2 29.7 39.4 34.9 42.2 48.3 Λ 0.016 0.16 0.51 0.63 2.06 4.03 Ξ+− 0.47 1.37 2.44 2.43 3.56 4.49 Ξ 0.0026 0.027 0.089 0.143 0.42 0.82 Ω 0.013 0.068 0.14 0.144 0.27 0.38 Ω 0.0008 0.0086 0.022 0.030 0.083 0.16 η 8.70 16.7 19.9 24.1 38.0 55.2 η′ 0.44 1.14 1.10 1.41 2.52 3.76 ρ0 12.0 19.4 14.0 18.4 32.1 42.3 ω(782) 6.10 13.0 10.8 15.7 27.0 38.5 f0(980) 0.56 1.18 0.83 1.27 2.27 3.26 K0(892) 5.42 13.7 11.03 12.4 18.7 26.6 ∆0 38.7 33.43 25.02 26.6 27.2 28.2 ∆++ 30.6 25.62 22.22 24.2 25.9 26.9 Λ(1520) 1.36 2.06 1.73 1.96 2.62 2.99 Σ−(1385) 2.51 3.99 4.08 4.26 5.24 5.98 Ξ0(1530) 0.16 0.44 0.69 0.73 1.14 1.44 RESONANCES NEED ATTENTION, NOT IN FIT Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 13

PREDICTIONS: AGS/SPS particle yields including NA49 2008 data, all SHARE 2.2 : E [A GeV] 11.6 20 30 40 80 158 √sNN [GeV] 4.84 6.26 7.61 8.76 12.32 17.27 yCM 1.6 1.88 2.08 2.22 2.57 2.91

N4π/ centr. m.c. 7% 7% 7% 7% 5% b B B 375.6 348.1 348.6 349.9 349.5 361.7 (s ≡s¯)/(−s +¯s) 0 -0.119 -0.037 -0.007 -0.017 -0.064 − π+ 134.0 189.9 243.3 292.5 434.7 617.2 π− 161.2 223.4 278.5 324.1 469.6 663.7 K+ 17.5 41.1 50.2 53.4 72.7 111.3 K− 3.60 10.3 15.9 19.7 33.4 54.7 KS 10.9 26.3 33.1 36.2 52.1 81.3 φ 0.47 1.82 2.10 2.64 4.23 7.37 p 173.2 162.9 166.2 137.2 138.6 145.9 p¯ 0.022 0.207 0.57 0.74 2.46 5.39 Λ 18.7 29.3 39.5 36.9 41.3 48.5 Λ 0.016 0.16 0.40 0.62 1.77 4.02 Ξ+− 0.49 1.34 2.45 2.77 3.42 4.55 Ξ 0.0026 0.028 0.065 0.145 0.35 0.82 Ω 0.014 0.065 0.14 0.178 0.26 0.39 Ω 0.0008 0.0089 0.014 0.031 0.067 0.16 η 8.50 16.7 19.5 23.2 36.2 55.6 η′ 0.43 1.13 1.06 1.40 2.34 3.78 ρ0 11.2 19.0 13.1 18.9 30.6 44.3 ω(782) 5.94 12.9 11.1 14.9 25.7 38.4 f0(980) 0.54 1.15 0.85 1.21 2.14 3.21 K0(892) 5.72 12.3 9.84 11.9 17.4 26.8 ∆0 37.9 33.1 25.16 26.3 26.9 28.0 ∆++ 29.7 26.08 22.18 24.4 25.7 26.7 Λ(1520) 1.33 2.0 1.74 2.11 2.52 2.99 Σ−(1385) 2.02 3.88 4.11 4.51 5.09 5.99 Ξ0(1530) 0.16 0.43 0.69 0.84 1.08 1.45 RESONANCES NEED ATTENTION, NOT IN FIT Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 14

What is DIFFERENT with RESONANCES

The combination of the experimental invariant mass method with the large, typ- ically 10 times greater resonant scattering cross sections means the OBSERVED resonances freeze-out LATE and thus we have to use of an “after burner” in the study of resonance chemical freeze-out.

The initially produced resonances, observed in terms of the invariant mass signature, are practically invisible if there is more than 1fm /c of hadrons (G. Torrieri, 2002) and/or one more scattering, The observed yield of resonances is ﬁxed by the physical conditions prevailing at the last scattering of the reacting particles – hence today we EVOLVE the resonance populations numerically.

We study reactions such as 1+2 3 ↔ example: Λ(1115) + π Σ(1385) ↔ Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 15

Time evolution equations

i j 1 dN3 dW1+2 3 dW3 1+2 = → → , i,j channels V dt dV dt − dV dt Xi Xj Resonance yield change = resonance formation - resonance decay The invariant rates are: (follows T. Kodama et al, to be published)

j 3 3 3 dW3 1+2 g3d p3 d p1 d p2 → = 3 f3 3 (1 f1) 3 (1 + f2) dV dt Z 2E3(2π) Z 2E1(2π) − Z 2E2 (2π) ×

1 2 (2π)4 δ4 (p + p p ) p M j p p × 1 2 − 3 g h 3 1 2i 3 Xspin

i 3 3 3 dW1+2 3 g1d p1 g2d p2 d p3 → = 3 f1 3 f2 3 (1 f3) dV dt Z 2E1(2π) Z 2E2(2π) Z 2E3 (2π) − ×

1 2 (2π)4 δ4 (p + p p ) p p M i p × 1 2 − 3 g g h 1 2 3i 1 2 Xspin

Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 16

We ﬁnd i i dW1+2 3 dW3 1+2 i Υ → = Υ Υ → = R 3 dV dt 1 2 dV dt using 1 u p/T 1 f = Υ− e · f ± ± ± where Fermi (f+) and Bose (f ) distributions are implied, − 1 1 f = , f+ = − Υ 1eu p/T 1 Υ 1eu p/T +1 − · − − · i i and time reversal invariance, i.e. M = M †,

2 2 p p M i p = p M i p p h 1 2 3i h 3 1 2i with the invariant, per time and volume, symmetric channel RATE Ri is: 3 1 3 1 3 1 i d p1 f1Υ1− d p2 f2Υ2− d p3 f3Υ3− 4 4 i 2 R = (2π) δ (p1 + p2 p3) p1p2 M p3 ZZZ 2E (2π)3 2E (2π)3 2E (2π)3 − h i 1 2 3 Xspin

In Boltzmann limit Υ-dependence completely cancels in R (appropriate for all massive resonances, not for π). Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 17

Computing the Resonance Yield The relativistic Boltzmann particle yield is: N T 3 m i = Υ g x2K (x ), x = i V i 2π2 i i 2 i i T The in medium (Fermi blocked/Bose enhanced) lifespan of particle 3 is: 1 V − dN3/dΥ3 i τ3 Υ3 i , for τ3 omit ≡ i dW3 1+2/dV dt → Xi P The rate equation is: dΥ3 i i 1 1 1 1 = Υ Υ + Υ3  +  dτ 1 2 τ i τ τ − j Xi 3 T S Xj τ3   where we have also introduced characteristic time constants of temperature T and entropy S evolution 1 d ln(x 2K (x )) 1 d ln(V T 3) = 3 2 3 T˙ , = T˙ . τT − dT τS − dT

T˙ 1 2(vτ/R )+1 where we simplify the numerics by using = ⊥ Inga solves this sys- T −3 τ tem of equations numerically, using classical fourth order Runger-Kutta method.

The big question is WHAT reactions are included and why equilibrium never occurs! 2nd Q: if γ ,γ = 1 the initial (for this example Λ(1115) + π Σ(1385)) s q 6 ↔ Υ (0)Υ (0) = γ4γ =1 and time evolution begins. 1 2 q s 6 Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 18

Reactions RELEVANT to understand Σ(1385), Λ(1520)

2300 N (2250) Σ Λ (2250, ?) 2200 (2220) (2190) (2110) 2100 (2100) (2030, 7/2, 180) 2000 (1940, 3/2, 220)

1900 (1915) 29 (1890) (1830) 34 (1775, 5/2, 120) 1800 35? (1800) 39 (1750,1/2, 90) (1720) 1190+ η 25 44 27? (1690) E [MeV] 1700 (1670, 3/2, 60) 4?? 22?? (1670 ) (1660 ) (1520)+ π (1650) 29 71? 49 13 7?? 1600 19 35? π 39 (1600) (938)+K+ 7 22 (1535) (1385)+ π } 34 1500 (1520) (1520, 3/2, 15.6) 7 (1440) 35? 35 (938)+K 14 (1385, 3/2,37) } 7 1400 6.5 (1405) 4 π 1300 (1190)+ 33

(1115) + π 1200 Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 19

Evolution of Σ(1385)

0.5

0.48 1.2 0.46 RHIC 1.1 0.44 in tot

Λ 0.42 1 / ob (1385)

Σ 0.4 T, MeV γ

q (1385)

0.9 Σ 140, 1.6 0.38 (1385)/ 140, 1.6, d.ch. γ Σ T ,MeV 160, 1.27 in q 140, 1.6 160, 1.27, d.ch. 0.36 0.8 140, 1.6, d.ch. 180, 1 160, 1.27 180, 1, d.ch. 0.34 160, 1.27, d.ch. 0.7 180, 1 180, 1, d.ch. 0.32 ϒ ϒ Σ(1385) = Λ (1115) SHARE, Σ +/Λ 0 0.6 0.3 100 120 140 160 180 100 120 140 160 180 T [MeV] T [MeV]

Σ(1385)ob = Σ(1385) + YΣ(1520)∗ 0 Λtot =0.91Σ(1385) + Λ + Σ (1193) + Y ∗ Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 20

Evolution of Λ(1520)

0.11 1.1 0.1

1 0.09 in tot

Λ 0.08 / ob (1520) 0.9 Λ 0.07 (1520) T, MeV γ Λ 0.06 (1520)/ 0.8 q γ Λ T ,MeV q 140, 1.6 in 140, 1.6, d.ch. 0.05 140, 1.6 160, 1.27 140, 1.6, d.ch. 0.7 160, 1.27, d.ch. 160, 1.27 0.04 160, 1.27, d.ch. 180, 1 RHIC & SPS 180, 1, d.ch. 180, 1 0.03 High centrality 180, 1, d.ch. ϒ =ϒ 0.6 Λ(1520) Λ(1115) SHARE, Λ(1520)/ Λ0 0.02 100 120 140 160 180 100 120 140 160 180 T [MeV] T [MeV] For Λ(1520) “dead channel” model relevant: Since we do not do a full momentum space distribution, but assume that Boltzmann exponential is achieved we overstate the rates when T low and mass of involved resonances high. So we close channels which require m (m + m ) > 300 MeV. 3 − 1 2 Johann Rafelski, Arizona/LMU WPCF08, September 10-13, 2008 Resonances do not Equilibrate page 21

Conclusions • Bulk hadronization of QGP alters baryon to meson ratio, requires γ 1.6 q → • High CL fit of all data, also the K+/π+ horn as function of energy. • Shift in hadronization condition at the horn, from an under-saturated system with large V, T to an oversaturated one with smaller V, T . How so: effectively massive valance quarks melt to perturbative quarks. • We find an universal critical hadronization pressure P 78.5 MeV/fm3 for ≃ hadronization above horn reaction energy. Indication of sudden breakup - common chemical and thermal freeze-out of all particles. • We address resonance puzzle (some resonances enhanced some suppressed - for all hadronization models. We evolve the resonances in a chemical pop- ulation model allowing for 1+2 3 reactions. A highly interwoven set of ↔ particle populations is solved numerically. • We find that wide resonances and here specifically Σ(1385) is strongly enhanced, dense pion gas pushes many Λ over to Σ(1385) • The narrow Λ(1520) acts as a stable state - it is mainly depleted by pions pushing it over to high level resonances. This effect is particularly strong if we observe that there are fewer high energy particles than Boltzmann distribution predicts in a rapidly expanding and cooling fireball - “dead channel model”.