formation of strangeness-nuclei at...

Hyp2012, 04.10.12

Formation of strangeness-nuclei at Formation of strangeness-nuclei at PPANDAANDA

T. GaitanosT. Gaitanos

IntroductionIntroductionTheoretical backgroundTheoretical backgroundRBUU+SMM hybrid modelTesting strangeness & fragmentationTesting strangeness & fragmentationStrangeness production & fragment yields/spectra for p+X, p+X & X+XResults for Results for PPANDAANDAprimary target: p+X → ΞX, secondary target: Ξ+X → AA

ΛΛΛΛX

Final remarksFinal remarks

together with A.B. Larionov, H. Lenske, U. Moseltogether with A.B. Larionov, H. Lenske, U. Mosel

supported by DFG and in part by I3HP SPHEREsupported by DFG and in part by I3HP SPHERE

Hyp2012, 04.10.12

Introduction…Introduction…

hyperon-baryon hyperon-hyperonhyperon-hyperon

explore

crucial to understand the strangeness sector of the hadronic EoScrucial to understand the strangeness sector of the hadronic EoSdirect implications for nuclear astrophysics (max. mass of neutron stars)direct implications for nuclear astrophysics (max. mass of neutron stars)

antiproton-nucleus reactionsantiproton-nucleus reactionsHypHI: HypHI: HHeavy-eavy-IIon collisionson collisions

Λ,Σ,π,Κ,...

Λ,Σ,π,Κ,...

Hyp2012, 04.10.12

Relativistic hypernuclei…Relativistic hypernuclei…

Theoretical frameworkTheoretical frameworkPhase-Space evolution Phase-Space evolution transport approaches (INC,BUU,RBUU,VUU,(Ur)QMD,HSD,…)Description of fragment formation Description of fragment formation statistical picture, e.g., SMM, Botvina & MishustinDescription of hypernuclei formation?Description of hypernuclei formation?Phase-Space coalescence (in coordinate and) in momentum space

(SMM+H: Botvina & Pochodzalla, PR C76 ('07) 024909, PL B697 ('11) 222) See also: Botvina, et al., Phys. Rev. C86 ('12) 011601, Nucl. Phys. A881 ('12) 228, Phys. Lett. B714 ('12) 85, Phys. Rev. C84 ('11) 064904

π

ΛΛ

ΛΛ

π

ΛΛ

ΛΛ

ΚΚ

ΚΚ

Primary : BB->BΛK, BBKKSecondary: πB->ΛK, BKK

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

1. target: pp->ΛΛ, ΞΞ, KKπ...(annih.) πB->ΛK, BKK (s=0) KB-> KΞ (s=-1)

2. target: ΞB->ΞB, ΛΛ (s=-2)

Hyp2012, 04.10.12

GiBUU-group: Buss, et al., Phys. Rep. 512512 (2012) 1

Collision term:Collision term:

primary: BB → mesons BB→ΛΛ, ΞΞ (data)

Secondary: ΞΒ→ΛΛ (Nijmegen-calc.), KB→ΞK (data), ΛΒ↔ΣB (data,Nijmegen-calc.)

Golubeva, Pshenichnov, et al., NP A537 393

Non-Equilibrium stage…Non-Equilibrium stage…

Standard Relativistic Mean-Field (RMF)Standard Relativistic Mean-Field (RMF) Non-linear Walecka model (soft EoS)

gωΝ=-ξgωΝ, gσΝ=ξgσΝ (ξ~0.2-0.3)

→ good description of pp-nucleus-nucleus ((but not for p-nucleus) opt. Potentials Uopt

Consistent description of both, in-medium p and p Uopt

:

→ Non-Linear Derivative (NLD) model: Gaitanos/Kaskulov, arXiv:1206.4821

Larionov, et al., PR C80,021601(R)

Lalazissis, et al., PL B671 36

Formation of single-Formation of single-ΛΛ & double- & double-ΛΛΛΛ hypernuclei hypernuclei

Fragments: SMM, Botvina/Mishustin, Phys. Rep. 257 133

Hyperfragments: phase-space coalescence Gaitanos, et al., NP A881 240

Hyp2012, 04.10.12

GiBUU-group: Buss, et al., Phys. Rep. 512512 (2012) 1

Collision term:Collision term:

primary: BB → mesons BB→ΛΛ, ΞΞ (data)

Secondary: ΞΒ→ΛΛ (Nijmegen-calc.), KB→ΞK (data), ΛΒ↔ΣB (data,Nijmegen-calc.)

Golubeva, Pshenichnov, et al., NP A537 393

Non-Equilibrium stage…Non-Equilibrium stage…

Standard Relativistic Mean-Field (RMF)Standard Relativistic Mean-Field (RMF) Non-linear Walecka model (soft EoS)

gωΝ=-ξgωΝ, gσΝ=ξgσΝ (ξ~0.2-0.3)

→ good description of pp-nucleus-nucleus ((but not for p-nucleus) opt. Potentials Uopt

Consistent description of both, in-medium p and p Uopt

:

→ Non-Linear Derivative (NLD) model: Gaitanos/Kaskulov, arXiv:1206.4821

Larionov, et al., PR C80,021601(R)

Lalazissis, et al., PL B671 36

Formation of single-Formation of single-ΛΛ & double- & double-ΛΛΛΛ hypernuclei hypernuclei

Fragments: SMM, Botvina/Mishustin, Phys. Rep. 257 133

Hyperfragments: phase-space coalescence Gaitanos, et al., NP A881 240

Hyp2012, 04.10.12

GiBUU-group: Buss, et al., Phys. Rep. 512512 (2012) 1

Collision term:Collision term:

primary: BB → mesons BB→ΛΛ, ΞΞ (data)

Secondary: ΞΒ→ΛΛ (Nijmegen-calc.), KB→ΞK (data), ΛΒ↔ΣB (data,Nijmegen-calc.)

Golubeva, Pshenichnov, et al., NP A537 393

Non-Equilibrium stage…Non-Equilibrium stage…

Standard Relativistic Mean-Field (RMF)Standard Relativistic Mean-Field (RMF) Non-linear Walecka model (soft EoS)

gωΝ=-ξgωΝ, gσΝ=ξgσΝ (ξ~0.2-0.3)

→ good description of pp-nucleus-nucleus ((but not for p-nucleus) opt. Potentials Uopt

Consistent description of both, in-medium p and p Uopt

:

→ Non-Linear Derivative (NLD) model: Gaitanos/Kaskulov, arXiv:1206.4821

Larionov, et al., PR C80,021601(R)

Lalazissis, et al., PL B671 36

Formation of single-Formation of single-ΛΛ & double- & double-ΛΛΛΛ hypernuclei hypernuclei

Fragments: SMM, Botvina/Mishustin, Phys. Rep. 257 133

Hyperfragments: phase-space coalescence Gaitanos, et al., NP A881 240

Hyp2012, 04.10.12

GiBUU-group: Buss, et al., Phys. Rep. 512512 (2012) 1

Collision term:Collision term:

primary: BB → mesons BB→ΛΛ, ΞΞ (data)

Secondary: ΞΒ→ΛΛ (Nijmegen-calc.), KB→ΞK (data), ΛΒ↔ΣB (data,Nijmegen-calc.)

Golubeva, Pshenichnov, et al., NP A537 393

Non-Equilibrium stage…Non-Equilibrium stage…

Standard Relativistic Mean-Field (RMF)Standard Relativistic Mean-Field (RMF) Non-linear Walecka model (soft EoS)

gωΝ=-ξgωΝ, gσΝ=ξgσΝ (ξ~0.2-0.3)

→ good description of pp-nucleus-nucleus ((but not for p-nucleus) opt. Potentials Uopt

Consistent description of both, in-medium p and p Uopt

:

→ Non-Linear Derivative (NLD) model: Gaitanos/Kaskulov, arXiv:1206.4821

Larionov, et al., PR C80,021601(R)

Lalazissis, et al., PL B671 36

Formation of single-Formation of single-ΛΛ & double- & double-ΛΛΛΛ hypernuclei (GiBUU+SMM) hypernuclei (GiBUU+SMM)

Fragments: SMM, Botvina/Mishustin, Phys. Rep. 257 133

Hyperfragments: phase-space coalescence Gaitanos, et al., NP A881 240

Hyp2012, 04.10.12

Collision term: Collision term: ppp-> X (primary elementary channels)…p-> X (primary elementary channels)…

Golubeva, Pshenichnov, et al., NP A537 ('92) 393

Statistical annihilation model (pp-> mesons) up to 6-particles final states (π,η,ω,ρ,K,K,K*,K*)

Other channels (pp-> BB)

Larionov, T.G., Lenske, Mosel, arXiv:1209.1966

Hyp2012, 04.10.12

Collision term: secondary elementary channels…Collision term: secondary elementary channels…Hyperon-Nucleon rescattering (ΣΝ → ΛΝ)

Antikaon-Nucleon rescattering (KΝ → ΞΚ), similar situation

Cascade-Nucleon rescattering (ΞΝ → ΛΛ), Extended-Soft-Core (ESC), Rijken et al.

T.G., Larionov, Lenske, Mosel, NP A881 240

Hyp2012, 04.10.12

PPANDA:ANDA: pp+X (primary target)...+X (primary target)...

...rapidity spectra

Good description of strangeness data

Secondary channels important!

y

Larionov, T.G.,Mosel, ArXiv:1209.1966, Phys. Rev. C85, 024614

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

PPANDA:ANDA: pp+X (primary target)+X (primary target)......

Low energy Ξ production due to secondary channels!

PΞ ~ 1 GeV/c ==> Ekin

~ 0.3 GeV

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Larionov, T.G.,Mosel, ArXiv:1209.1966, Phys. Rev. C85, 024614

Hyp2012, 04.10.12

PPANDA:ANDA: pp+X (primary target)+X (primary target)......

EE** = Ep+(Mtarg-Btarg)Atarg-(Mres-Bres)Ares-Eem-Erec

Good description of excitation energy spectrum

data: PRC63, 034616

T.G., Larionov,Lenske,Mosel, NP A881 240

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

PPANDA:ANDA: pp+X (primary target)+X (primary target)... ...

Overal good description of different fragment multiplicities

data: PRC63, 034616

T.G., Larionov,Lenske,Mosel, NP A881 240

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

PPANDA:ANDA: pp+X (primary target)+X (primary target)......

...rapidity spectra

Coalescence with stopped Λ's possible

No coalescence with Ξ's (in 2th target)

T.G., Larionov,Lenske,Mosel, NP A881 240

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

PPANDA:ANDA: ΞΞ+X (secondary target)+X (secondary target)......

GiBUU+SMM+GiBUU+SMM+momentum coalescence with captured Ξ & ΞΝ →ΛΛ

Copious production of ΛΛ−hypernuclei via Ξ-capture in 2th target...

Process strongly dependent on Ξ-energy (ΞΝ →ΛΛ)

fragments

ΛΛ-fragments

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

PPANDA:ANDA: pp+Cu →+Cu → ΞΞX & X & ΞΞ+Cu...+Cu...

Total yield

Depends also on exp. (material in between, etc.)

emitted Ξ's

from primary target

produced ΛΛ−fragments

from secondary target

T.G., Larionov,Lenske,Mosel, NP A881 240

Hyp2012, 04.10.12

Final remarks…Final remarks…

Theoretical studies: “FAIR” @ GiessenTheoretical studies: “FAIR” @ Giessen GiBUU+SMM: NE-dynamics + statistical process of fragmentationGiBUU+SMM: NE-dynamics + statistical process of fragmentation suitable tool for HypHI- & suitable tool for HypHI- & PPANDA-reactionsANDA-reactions

Predictions on single-Predictions on single-ΛΛ hypernuclei (HypHI) hypernuclei (HypHI) σσ ~ ~ µµb for b for ΛΛH & H & ΛΛHe in spectator/target fragmentation in HICHe in spectator/target fragmentation in HIC consistency with HypHI-experiment ?... (T. Saito)consistency with HypHI-experiment ?... (T. Saito)

Predictions on double-Predictions on double-ΛΛ hypernuclei ( hypernuclei (PPANDA)ANDA) production of production of ΛΛ-nuclei in first target with very low Prob., -nuclei in first target with very low Prob., ΞΞ's escape's escape ΞΞ+X (secondary target) +X (secondary target) →→ AA

ΛΛΛΛ+X, production of A+X, production of AΛΛΛΛ, energy dependent, energy dependent

To do/on work....To do/on work.... Collision termCollision term: primary & secondary elementary channels under control?: primary & secondary elementary channels under control?

in-medium hyperon-nucleon scatteringin-medium hyperon-nucleon scattering Drift termDrift term: Momentum dependent mean-field dynamics: Momentum dependent mean-field dynamics

Hyp2012, 04.10.12

Backup slides

Hyp2012, 04.10.12

p+X-Reactions:p+X-Reactions: switch from BUU switch from BUU →→ SMM...SMM...

Def. Of residual spurceDef. Of residual spurce

particles with ρ>ρsat/100

SMM

SMM

SMM

Hyp2012, 04.10.12

NLD: p & NLD: p & pp opt. potentials… opt. potentials…

T.G., Kaskulov & Lenske, PL B703 (2011) 193

T. G., M. Kaskulov, arXiv:1206.4821 [nucl-th]

proton-nucleus

antiproton-nucleusRHD

Hyp2012, 04.10.12In preparation...

PPANDA:ANDA: ΞΞ+X@(3-5)GeV...+X@(3-5)GeV...

Ξ-capture in 2th target strongly energy dependent

Repulsive RMF fields at high energies & ΞΝ →ΛΛ

ΛΛ

ΞΞp Κ,Kπ Ξ ΛΛ

Hyp2012, 04.10.12

Numerical realization (Test-Particle Ansatz):Numerical realization (Test-Particle Ansatz):Initialization Propagation (Vlasov, collisions)

Initialization: „test particles“ initialized according to empirical density distributions

Problem: density profiles not consistent with mean-field used in propagationSolution: Use the same energy density functional ε[ρp,ρn] for initialization & propagation

Relativistic Thomas Fermi (RTF) for spherical nuclei

Old initialization

Old initialization

New initialization

New initialization

Important in calculating EImportant in calculating Eexcexc

Important in calculating A,Z Important in calculating A,Z

PR PR C81C81, (2010), , (2010), 054316

Hyp2012, 04.10.12

SpectatorsSpectators

Well defined conditions after onset of instability…

SpectatorsSpectators

…and onset of equilibration

Def. ofSpectatorsDef. ofSpectators

Y(0)>0.75 +ρ>ρsat/100

π

ΛΛ

ΛΛ

π

ΛΛ

ΛΛ

Σπ

πΚ

PL PL B663B663, 197 (08) & PL , 197 (08) & PL B675B675 (09) 297 (09) 297

SMM

X+X-Reactions, spectators:X+X-Reactions, spectators: BUU BUU →→ SMM...SMM...

Hyp2012, 04.10.12

absolute yieldsabsolute yields from spectator fragmentation in

Au+Au@0.6AGeV

(ALADIN-data)

fragment velocity spectrafragment velocity spectra

in Xe+Pb@1.0AGeV

data:Henzlova, PRC78, 044616

GiBUU+SMM:GiBUU+SMM: spectator fragmentation in X+X... spectator fragmentation in X+X...

PL PL B663B663, 197 (08) & PL , 197 (08) & PL B675B675 (09) 297 (09) 297

Hyp2012, 04.10.12

HypHI:HypHI: Li+C@2AGeV... Li+C@2AGeV... π

ΛΛ

ΛΛ

π

ΛΛ

ΛΛ

Σπ

πΚ

BUUBUU: fragmenting sources & strangeness (consistent with FOPI/KaoS)

SMMSMM: spectator fragmentation (consistent with ALADIN)

6Li-fragmentation12C-fragmentation

ΛΛ & & AAX coalescence X coalescence possiblepossible

Hyp2012, 04.10.12

HypHI:HypHI: Li+C@2AGeV... Li+C@2AGeV... π

ΛΛ

ΛΛ

π

ΛΛ

ΛΛ

Σπ

πΚ

In preparation...

Coal.Coal.: momentum coalescence for Λ close to spectators

EstimateEstimate: projectile/target fragmentation: σ(3HΛ, 4,5HeΛ) ~ (6-10)µb

PL B675 (09) 297