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W. Trautmann GSI Helmholtzzentrum, Darmstadt, Germany Symposium on applied nuclear physics and innovative technologies Kraków, June 5, 2013
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binding energy of nuclei Tsang et al., PRC (2012) following Brown, PRL (2000) B(A,Z) = a V ·A - a S ·A 2/3 - a C ·Z 2 /A 1/3 - a sym ·(A-2Z) 2 /A + a P ·δ/A 1/2 nuclear matter E/A(ρ,δ) = E/A(ρ,δ=0) + E sym (ρ)·δ 2 + O(δ 4 ) a sym = 23.2 MeV with asymmetry parameter δ = (ρ n –ρ p )/ρ
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isospin diffusion figure from Lattimer and Prakash, Phys. Rep. (2007) Tsang et al., PRL 102, 122701 (2009): 0.4≤ γ ≤1.0 ( 112,124 Sn+ 112,124 Sn, 50 AMeV) 45 MeV ≤L≤ 100 MeV from isospin diffusion and neutron-proton double ratios interpreted with ImQMD calculations by Y. Zhang et al. recently M.B. Tsang, PRC 86 (2012): L = 70 ± 15 MeV previously: E sym (ρ) ≈ 31.6·(ρ/ρ 0 ) 0.69 with IBUU04, Li and Chen, PRC72(2005) remember T. Twaróg, yesterday
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=1.5 =0.5 parameterization in transport theory: UrQMD, Q.F. Li et al. Fuchs and Wolter, EPJA 30 (2006) nuclear many-body theory the symmetry energy E sym = E sym pot +E sym kin L = 3ρ o ·dE sym /dρ at ρ=ρ 0 ρ/ρ0ρ/ρ0 asymmetry parameter δ = (ρ n –ρ p )/ρ E A (ρ,δ) = E A (ρ,0) + E sym (ρ) ∙ δ 2 + O(δ 4 ) γ L (MeV) 0.557 1.0 90 1.5123 = 22 MeV·(ρ/ρ 0 ) γ +12 MeV·(ρ/ρ 0 ) 2/3 linear supersoft
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slide from talk of X. Viñas, ECT*, Trento, June 2011
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Tsang et al., PRC (2012)
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high density: needs higher energy observables: collective flows and meson production central density number of baryons and average density in high –density phase Xu et al., arXiv:1305.0091
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differential: neutrons vs. protons t vs. 3 He, 7 Li vs 7 Be,... UrQMD: significant sensitivity predicted; neutron vs. proton elliptic flows inverted reanalysis of FOPI-LAND data Au+Au @ 400 MeV per nucleon: γ pot = 0.9 ± 0.4 from n-H ratios Russotto, Wu, Zoric, Chartier, Leifels, Lemmon, Li, Łukasik, Pagano, Pawłowski, Trautmann, PLB 697 (2011) 471 Trautmann and Wolter, review in IJMPE 21 (2012) high density:elliptic flow (elliptic flow squeeze-out)) (directed flow) v 2 second azim. Fourier coeff.
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differential: neutrons vs. protons t vs. 3 He, 7 Li vs 7 Be,... UrQMD: significant sensitivity predicted; neutron vs. proton elliptic flows inverted reanalysis of FOPI-LAND data Au+Au @ 400 MeV per nucleon: γ pot = 0.9 ± 0.4 from n-H ratios Russotto, Wu, Zoric, Chartier, Leifels, Lemmon, Li, Łukasik, Pagano, Pawłowski, Trautmann, PLB 697 (2011) 471 Trautmann and Wolter, review in IJMPE 21 (2012) high density:elliptic flow asy-stiff asy-soft UrQMD =1.5 =0.5
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differential: neutrons vs. protons t vs. 3 He, 7 Li vs 7 Be,... UrQMD: significant sensitivity predicted; neutron vs. proton elliptic flows inverted reanalysis of FOPI-LAND data Au+Au @ 400 MeV per nucleon: γ pot = 0.9 ± 0.4 from n-H ratios Russotto, Wu, Zoric, Chartier, Leifels, Lemmon, Li, Łukasik, Pagano, Pawłowski, Trautmann, PLB 697 (2011) 471 Trautmann and Wolter, review in IJMPE 21 (2012) high density:elliptic flow asy-stiff asy-soft UrQMD v 2 ratios =1.5 =0.5
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=1.5 =0.5 param. in transport: UrQMD, Q.F. Li et al. the symmetry energy ρ/ρ0ρ/ρ0 FOPI/LAND γ L (MeV) 0.557 1.0 90 1.5123 E sym = E sym pot +E sym kin L = 3ρ o ·dE sym /dρ at ρ=ρ 0 L ≈ 80 MeV = 22 MeV·(ρ/ρ 0 ) γ +12 MeV·(ρ/ρ 0 ) 2/3 Fuchs and Wolter, EPJA 30 (2006) asymmetry parameter δ = (ρ n –ρ p )/ρ E A (ρ,δ) = E A (ρ,0) + E sym (ρ) ∙ δ 2 + O(δ 4 )
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GSI Helmholtzzentrum für Schwerionenforschung
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FOPI/LAND experiment SB: shadow bar for background measurement LAND 2 LAND 1 SB acceptance in p t vs. rapidity main yield here neutron squeeze-out: Y. Leifels et al., PRL 71, 963 (1993) Forward Wall for centrality and reaction-plane orientation >700 elements Large Area Neutron Detector 5 m
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azimuthal angular distributions near target rapidity mostly directed flow at mid-rapidity strong squeeze-out near projectile rapidity mostly directed flow fitted with: f(Δφ)=a 0 *(1.0+2v 1 *cos(Δφ)+2v 2 *cos(2Δφ)) Δφ = φ particle – φ reaction plane and compared to UrQMD model predictions Q. Li et al., J. Phys. G 31(2005); 32 (2006) relative to the reaction plane for neutrons, background subtracted 0 Δφ 2 π
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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 + 197 Au @ 400 A MeV 96 Ru + 96 Ru @ 400 A MeV 96 Zr + 96 Zr @ 400 A MeV KRATTA
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experiment in May 2011 ALADiN ToF-Wall Kraków hodoscope beam LANDCHIMERA
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experiment in May 2011 beam LANDCHIMERA Kraków hodoscope coverage β t γ vs. y flow at mid-rapidity
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HIC scenario: - fast neutron emission (mean field) -NN=>NΔ threshold effects -nn=>pΔ - (no chemical equilibrium) see, e,g, di Toro et al., J.Phys.G (2010) high density: isotopic particle (double) ratios static calc. for infinite nucl. matter FOPI data HIC Ferini et al. (RMF) stiffer for ratio up Xiao et al. (IBUU) softer “ Feng & Jin (ImIQMD) stiffer “ Xie et al. (ImIBL) softer “ consequence: extremely stiff (soft) solutions Au+Au PRC (2007) Reisdorf et al., NPA 781 (2007) K + /K 0 ratio π - / π + ratio 40 Ca+ 40 Ca
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authors of proposal 2009
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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, CREX (2015) increasingly more precise data from neutron-star observations, typically L ≈ 40 MeV; e.g. Steiner, Lattimer and Brown, ApJ (2010) high-densities probed in reactions at SIS energies; γ pot = 0.9 ± 0.4 from FOPI/LAND elliptic flow; super-soft ruled out; study of model invariance under way; analysis of ASY-EOS experiment in progress! kaon and pion ratios interesting probes but results presently inconclusive: new activity at RIKEN (Samurai) and MSU; HADES kaon data for Ar+KCl and Au+Au potentially useful interesting new results from effective field theory (ρ≤ρ 0 ) future: tidal polarizability of neutron stars via gravitational waves
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parameter test with Tübingen QMD*) conclusion: super-soft not compatible with FOPI-LAND data difference of neutron and proton squeeze-outs Au + Au @ 400 A MeV *) V.S. Uma Maheswari, C. Fuchs, Amand Faessler, L. Sehn, D.S. Kosov, Z. Wang, NPA 628 (1998) M.D. Cozma et al., arXiv:1305.5417 first steps towards model invariance: tested in UrQMD: FP1 vs. FP2, i.e. momentum dep. of NNECS tested in T-QMD: soft vs. hard compressibility K density dep. of NNECS asymmetry dep. of NNECS width L of nucleon wave packet momentum dependence of isovector potential supersoftsuperstiff
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parameter test with Tübingen QMD*) conclusion: super-soft not compatible with FOPI-LAND data difference of neutron and proton squeeze-outs Au + Au @ 400 A MeV *) V.S. Uma Maheswari, C. Fuchs, Amand Faessler, L. Sehn, D.S. Kosov, Z. Wang, NPA 628 (1998) M.D. Cozma et al., arXiv:1305.5417 supersoftsuperstiff
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analysis of π - / π + ratios in Au+Au at 400 A MeV FOPI data, Reisdorf et al., NPA (2007) π ratios + IBUU04: x=1 super soft Xiao et al., PRL 102 (2009) Feng and Jin, PLB 683 (2010) high density: inconsistent results from pion ratios π ratios + IBUU04: x=1 super soft π ratios + ImIQMD: SLy6 with =2 very stiff
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Fuchs and Wolter, EPJA 30 (2006) the symmetry energy asymmetry parameter δ = (ρ n –ρ p )/ρ E A (ρ,δ) = E A (ρ,0) + E sym (ρ) ∙ δ 2 + O(δ 4 ) parameterization in transport theory: Bao-An Li et al. force developed by Das, Das Gupta, Gale, and Bao-An Li, Phys. Rev. C 67 (2003) 034611. with explicit momentum dependence in the isovector part
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from Bao-An Li, Lie-Wen Chen, Farrukh J. Fattoyev, William G. Newton and Chang Xu, arXiv:1212.0284v1 Lecture at the International Summer School for Advanced Studies, July 2012, Predeal, Romania 21 refs10 refs the symmetry energy: present status (2012) near and below saturation density
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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
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Fuchs and Wolter, EPJA 30 (2006) 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 balance determines skin thickness E sym from nuclear many-body theory
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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 - 1.06 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.) for first results see S. Abrahamyan et al., PRL 108 (2012)
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7/7/2016W. Trautmann, GSI Darmstadt, Istanbul 200830 Coulomb excitation of the pygmy dipole resonance neutron(s) heavy fragment beam Crystal Ball with target Dipole magnet Aladin Neutron detector LAND ~20 m high-Z target projectile Coulomb excitation excitation energy reconstructed from four-momenta of all outgoing projectile- like particles and γ rays A. Klimkiewicz et al., PRC 76 (2007) (slide from talk at CHIMERA-GSI workshop)
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