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Formation of hypernuclei in reactions induced by heavy-ion and hadron beams. T. Gaitanos, H. Lenske, U. Mosel. Introduction Theoretical aspects Giessen-BUU (GiBUU) +SMM approach Applications-I: (X+X, p+X)@SIS Benchmark tests (fragmentation)
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Formation of hypernuclei in reactions induced by heavy-ion and hadron beams T. Gaitanos, H. Lenske, U. Mosel • Introduction • Theoretical aspects • Giessen-BUU (GiBUU) +SMM approach • Applications-I: (X+X, p+X)@SIS • Benchmark tests (fragmentation) • Applications-II: X+X@2AGeV (HypHI), p+X@50GeV (PANDA, J-PARC) • Predictions on hypernuclear production cross sections • Final remarks
* Explore YB- & YY-interaction HypHI: Hyperon Heavy-Ion Antiproton-proton Annihilation in Darmstadt Nuclear structure at the limits Z NuSTAR: Nuclear Structure, Astrophysics, Reactions N Introduction…
K L L,S,p,K,... L p p L L L,S,p,K,... K Relativistic hypernuclei… • Production of hypernuclei in relativistic HIC • Production of many hyperons from BB->BYK (3-body PS) • Secondary rescattering (pNYK) • Multiple coalescence of hyperons with fragments • Theoretical framework • Phase-Space evolution Transport approaches (INC,BUU,RBUU,CBUU,(Ur)QMD,HSD,…) • Description of fragment formation Statistical picture (SMM, Botvina & Mishustin) • Description of hypernuclei formation? • Phase-Space coalescence in coordinate and in momentum space
j,e E* Ai,Zi E*-e Ad,Zd Ad+n Ai Theoretical aspects… Initial non-equilibrium stage (http://gibuu.physik.uni-giessen.de/GiBUU) • Asymptotic equilibrated stage • Statistical Multifragmentation Model (SMM) • Fission/spallation, evaporation, multifragmentation… (with increasing excitation) • Statistical determination of partial decay widths Monte-Carlo method SMM code: Botvina & Mishustin, PR257(´95) 133
Application-I: Fragmentation in p+X@0.8 GeV (global aspects…) Charge distribution… Mass distribution… Exp. data: Benlliure et al., Nucl. Phys. A683 (2001) 513. Rejmund et al., Nucl. Phys. A683 (2001) 540 Phys. Lett. B 663, 197 (2008)
Final Result: Hybrid GiBUU+SMM • Asymptotic final state (SMM): Statistical decay of excited source • Pre-Equilibrium (GiBUU): high-energy n-emission, QE-peak Application-I: Fragmentation in p+X@0.8 GeV (energy spectra…) neutrons data: S. Leray et al., PRC65,044621 Prog. Part. Nucl. Phys. (2009), in press(arXiv:0811.3506)
Applications-II: Fragmentation in X+X reactions absolute yields from spectator fragmentation in Au+Au@0.6AGeV (ALADIN-data) fragment velocity spectra in Xe+Pb@1.0AGeV data: Henzlova, PRC78, 044616
Applications-II: Hypernuclei in spectator fragmentation… (HypHI, 12C+12C@2AGeV) • First transport theoretical predictions: total yields ~mb • Consistent with previous studies: M.Wakai, NPA547(92)89c Prog. Part. Nucl. Phys. (2009), in press (arXiv:0811.3506) Phys. Lett. B (2008), submitted
Applications-II: Hypernuclei from high energy proton-induced reactions… (PANDA/J-PARC, p+12C@50GeV) • Two sources (residual target+moving source) • Most of hyperons created & rescatter inside moving source Prog. Part. Nucl. Phys. (2009), in press (arXiv:0811.3506), Phys. Lett. B (2008), submitted
Conclusions… • Theoretical activities: “FAIR” @ Giessen • GiBUU+SMM: NE-dynamics + statistical process of fragmentation • GiBUU+SMM+L: model extension to hypernuclei (coalescence) • Theoretical predictions (low energy) • proper description of fragmentation process in spallation reactions • and in heavy-ion collisions • First theoretical predictions on hypernuclei (high energy) • s ~ mb for LH & LHe in spectator fragmentation in heavy-ion collisions • high energy LH & LHe in proton-induced reactions • Important for future experiments: FAIR @ GSI • HypHI (T. Saito) Li (C) +C@2AGeV starts soon… • PANDA exp. predictions on double strange hypernuclei
Getting started: Spectator fragmentation at Au+Au@0.6 GeV Prog. Part. Nucl. Phys. (2009), in press Phys. Lett. B (2008), submitted
Old initialization new initialization RTF-binding energy Old initialization new initialization New initialization: Binding energy & rms-radius in BUU…
Mean-field vs cascade – the role of the mean-field… (PANDA/J-PARC, p+12C@50GeV) central peripheral
Ground state in BUU-II: Results (application to proton-induced reactions)