Experimental determination of the symmetry energy W. Trautmann, GSI Helmholtzzentrum, Darmstadt, Germany Nuclear Equation of State for Compact Stars and Supernovae

from Fuchs and Wolter, EPJA 30 (2006) see also Baldo et al., NPA (2004) for very low density see, e.g., Natowitz et al., PRL104 (2010) Typel et al., PRC 81(2010) and NPA 887 (2012) the nuclear equation of state why so uncertain at high density? related to uncertainty of three-body and tensor forces at high density normal nuclear density E sym

 =1.5  =0.5 parameterization in transport theory: UrQMD, Q.F. Li et al. Fuchs and Wolter, EPJA 30 (2006) the symmetry energy E sym = E sym pot +E sym kin = 22MeV·(ρ/ρ 0 ) γ +12MeV·(ρ/ρ 0 ) 2/3 L = 3ρ o ·dE sym /dρ at ρ=ρ 0 ρ/ρ0ρ/ρ0 γ L (MeV) L = 66.5 MeV, I. Vidaña et al. PRC80 (2009) see also Lombardo et al., PRC85 (2012)

slide from talk of X. Viñas, ECT*, Trento, June 2011

I. neutron matter in the laboratory neutron skins e.g., 132 Sn, 208 Pb balance of asymmetry pressure inside and neutron-matter EoS at reduced density in skin δrδr r ρ neutron density ρ n proton density ρ p skin δR = 1/2 - 1/2

slide from talk of X. Viñas, ECT*, Trento, June 2011 Roca-Maza et al., PRL 106, (2011) Roca-Maza et al.: "... without assumption on the neutron density shape. δΔr np = 0.02 fm (δL~10 MeV) supported by theory." following earlier work by Brown (2000), Typel & Brown (2001), Furnstahl (2002) neutron skin and the symmetry energy

PREX I the Z 0 couples mainly to the neutron: weak charge of the proton: 1-4sinθ W with sinθ W =0.23 neutron radius of 208 Pb from parity-violating electron scattering Hall A Jefferson Lab polarized e GeV ≈ 60 μA 208 Pb target twin HRS θ lab ~ 5 o nearly only elastic events “a landmark for isospin physics” (Roca-Maza et al.)

neutron skin and the symmetry energy slide from talk of X. Viñas, ECT*, Trento, June 2011 error as predicted in proposal Roca-Maza et al., PRL 106, (2011) pygmy dipole resonance LAND/GSI δ np = 0.17 ± 0.02 A. Klimkiewicz, PRC 76 (2007) RQRPA calculations by N. Paar experim. result of PREX-I Abrahamyan et al., PRL 108 (2012)

neutron skin and the symmetry energy slide from talk of X. Viñas, ECT*, Trento, June 2011 Roca-Maza et al., PRL 106, (2011) anti-analog GDR (LAND) δ np = 0.18 ± 0.03 A.Krasznahorkay, arxiv RQRPA calculations by N. Paar, P. Ring, D. Vretenar et al. experim. result of PREX-I Abrahamyan et al., PRL 108 (2012) error as predicted in proposal

neutron skin and the symmetry energy slide from talk of X. Viñas, ECT*, Trento, June 2011 Roca-Maza et al., PRL 106, (2011) TU Darmstadt δ np = 0.16 ± 0.02 “Complete Electric Dipole Response in 208Pb”, Tamii et al., PRL 107 (2011) error as predicted in proposal experim. result of PREX-I Abrahamyan et al., PRL 108 (2012)

neutron skin and the symmetry energy slide from talk of X. Viñas, ECT*, Trento, June 2011 experim. result of PREX-I Abrahamyan et al., PRL 108 (2012) Roca-Maza et al., PRL 106, (2011) from neutron star radii and masses δ np = 0.15 ± 0.02 Steiner, Lattimer, Brown, ApJ 722 (2010) 33 error as predicted in proposal

HodoCT ALADiN Magnet TP-MUSIC IV TOF- Wall Target LAND Z resolution A resolution C. Sfienti et al., PRL 102 (2009), R. Ogul et al., PRC 83 (2011) main result: reduced symmetry energy of fragments in the hot environment; will affect neutron capture rates in SN 107 Sn 124 Sn 2m II. fragments and clusters from nearly symmetric matter 1.14 ≤ N/Z ≤ 1.48

HodoCT ALADiN Magnet TP-MUSIC IV TOF- Wall Target LAND ALADiN experiment S254: Z resolution A resolution C. Sfienti et al., PRL 102 (2009), R. Ogul et al., PRC 83 (2011) main result: reduced symmetry energy of fragments in the hot environment; will affect neutron capture rates in SN 107 Sn 124 Sn 2m Projectile fragmentation of neutron-rich and neutron-poor projectiles: 124 Sn, 107 Sn, 124 La

Statistical Multifragmentation Model SMM experiment surface alone symmetry term reduced at chemical freeze-out in multifragmentation reactions standard modified

can fragments survive in the hot environment? Mott points determined experimentally using equilibrium assumptions for cluster emissions from 40 Ar, 64 Zn + 112,124 47AMeV Hagel et al., PRL108 (2012) thermal freeze-out T=5 MeV for excited state temperatures (thermal freeze-out) Trautmann et al., PRC76 (2007) chemical freeze-out Texas A&M ALADiN Z bound Z max

ASY-EOS: differential elliptic flow (squeeze out) differential: neutrons vs. protons t vs. 3 He, 7 Li vs 7 Be,... UrQMD: significant sensitivity predicted; neutron vs. hydrogen flows inverted (Qingfeng Li and Paolo Russotto) reanalysis of FOPI-LAND data 400 MeV per nucleon: γ pot = 0.9 ± 0.4 Russotto, Wu, Zoric, Chartier, Leifels, Lemmon, Li, Lukasik, Pagano, Pawlowski, Trautmann, PLB 697 (2011) 471; Trautmann and Wolter, IJMPE 21 (2012) III. high density

 =1.5  =0.5 param. in transport: UrQMD, Q.F. Li et al. Fuchs and Wolter, EPJA 30 (2006) the symmetry energy E sym = E sym pot +E sym kin = 22MeV·(ρ/ρ 0 ) γ +12MeV·(ρ/ρ 0 ) 2/3 L = 3ρ o ·dE sym /dρ at ρ=ρ 0 ρ/ρ0ρ/ρ0 γ L (MeV) FOPI/LAND

μ-ball, CHIMERA, ALADIN Tof-wall for impact parameter orientation and modulus ALADIN ToF wall four rings of μ-ball four double rings of CHIMERA AsyEos experiment S394 in May 2011 studied reactions: 197 Au A MeV 96 Ru A MeV 96 Zr A MeV

authors of proposal 2009

experiment in May 2011 ALADiN ToF-Wall Kraków hodoscope beam LANDCHIMERA

summary and outlook L ≈ 60 MeV (γ ≈ 0.6) from nuclear structure and reactions probing densities of ≈ 2/3 ρ 0 ; big expectations on PREXII increasingly more precise data from neutron-star observations, typically L ≈ 40 MeV high-densities probed in reactions at SIS energies; analysis of ASY-EOS experiment in progress! kaon and pion ratios interesting probes but results presently inconclusive: new activity at RIKEN (Samurai) and MSU; analysis of HADES kaon data for Ar+KCl and Au+Au promising results from effective field theory new facilities under construction worldwide

results from FOPI/LAND experiment  =1.5  =0.5 neutron/hydrogen FP1: γ = 1.01 ± 0.21 FP2: γ = 0.98 ± 0.35 neutron/proton FP1: γ = 0.99 ± 0.28 FP2: γ = 0.85 ± 0.47 adopted: γ = 0.9 ± 0.4 parameters in UrQMD

FP1 FP2 Medium modifications (FU1, …) and momentum dependence (FP1, …) of nucleon-nucleon elastic Xsects parameterizations in UrQMD w/o momentum dep. Qingfeng Li et al., PRC 83 (2011)

new: result obtained with Tübingen QMD*) with FOPI filter bands show uncertainty due to isoscalar field “soft to hard” conclusion in paper: super-soft not compatible with FOPI-LAND data difference of neutron and proton squeeze-outs Au A MeV asy-stiff asy-soft *) V.S. Uma Maheswari, C. Fuchs, Amand Faessler, L. Sehn, D.S. Kosov, Z. Wang, NPA 628 (1998) M.D. Cozma, PLB 700, 139 (2011); arXiv: tested in UrQMD: momentum dep. of isoscalar field momentum dep. of NNECS tested in T-QMD: density dep. of NNECS asymmetry dep. of NNECS soft vs. hard EoS width of wave packets

HIC scenario: fast neutron emission (mean field effect) and transformation of neutron into proton in inelastic channels (no-chemical equilibrium) isotopic particle (double) ratios static calc. for infinite nucl. matter FOPI data HIC Ferini et al.stiffer for ratio up Xiao et al.softer “ Feng and Jinstiffer “ consequence: extremely stiff (soft) solutions Au+Au PRC (2007) Reisdorf et al., NPA781(2007)

analysis of π - / π + ratios in Au+Au at 400 A MeV (FOPI data, Reisdorf et al., 2007) π ratios + IBUU04: x=1 super soft Xiao et al., PRL 102 (2009) Feng and Jin, PLB 683 (2010) inconsistent results from pion ratios π ratios + IBUU04: x=1 super soft π ratios + ImIQMD: SLy6  =2 very stiff

Construction site of SPIRAL II at GANIL/Caen NeuLAND R3B/GSI-FAIR “terra nuova” for exploring terra incognita

SAMURAI dipole magnet at RIKEN Superconducting Analyzer for MUlti-particle from RAdio Isotope Beam with 7Tm of bending power TPC project for SAMURAI Tsang, Isobe, McIntosh, Murakami et al.