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Low density matterLow density matterprobed in multifragmentation reactionsprobed in multifragmentation reactions
W. TrautmannW. TrautmannGSI Helmholtzzentrum, Darmstadt, GermanyGSI Helmholtzzentrum, Darmstadt, Germany
Workshop „Workshop „Simulating the Supernova NeutrinosphereSimulating the Supernova Neutrinospherewith Heavy Ion Collisions“with Heavy Ion Collisions“
ECT* Trento, April 2014ECT* Trento, April 2014
ALADIN 1990-2004
historical and personal
MUSIC III
ToF
LynenLühningMüllerPochodzallaSannSchwarzSfientiet al.
V. Serfling
multifragmentation of relativistic projectiles
K. Turzó
isospin dependent multifragmentation of relativistic projectiles
main result:reduced symmetry energyrequired forliquid drop description offragments at freeze-out
K. Turzó
the nuclear phase diagram
NN2000 Strasbourg
as we explore it with multifragmentation
critical points fromJaqaman et al., PRC 27 (1983) 2782Müller & Serot, PRC 52 (1995) 2072Schnack & Feldmeier, PLB B 409 (1997) 6
astrophysical motivation
dashed:adiabatic evolution,e.g., collapse (along constant entropy per baryon S/B)
HodoCHodoCTT
ALADiALADiN N MagneMagnett
TP-MUSIC TP-MUSIC IVIV
TOF-TOF-WallWall
TargetTarget
LANDLAND
ALADiN spectrometer Z resolutionZ resolution
A resolutionA resolution
A. Schüttauf et al., NPA 607, 457 (1996)
main topic: projectile (multi)fragmentationcorrelation functions with hodoscopes(160 elements) in coincidence
107Sn 124Sn
2m
full acceptance for projectile fragments at E>400 A MeVdynamic range from Z<2 to Z=93 with good resolution
discrete states from correlations5Li
kinematic acceptance
secondary decay effectswith QSM at T=5 MeV
Au+Au50-200 A MeVcentral, 10% σreact
T=5 MeVuniversal and limit
V. Serfling et al., PRL 80 (1998)
He4 g.s. vs. 20.21+Li5 g.s. vs. 16.66Li6 2.19 vs. 4.31+5.65Be8-1 g.s. vs. 3.04Be8-2 g.s. vs. 17.64+Be8-3 17.64+ vs. 3.04
HeLi
Hedt
5Li4He8Be
5Li
150 A MeV
can fragments survive in the hot environment?
Mott points determined experimentallyusing equilibrium assumptions for cluster emissions from 40Ar, 64Zn + 112,124Sn @ 47AMeVHagel et al., PRL108 (2012)
thermal freeze-out 4He, 5Li
T=5 MeV for excited statetemperatures (thermal freeze-out)W.T. et al., PRC76 (2007)
chemical freeze-outlines from Typel et al. (2010)
ALADiN
Zbound
Zm
ax
THeLi
Au+Au@1000
isotopic effects in chemical freeze-out
from double isotope yield ratios: THeLi (3,4He,6,7Li)(Albergo's formula) TBeLi (7,9Be,6,8Li)
C. Sfienti et al., PRL 102 (2009)
isotopic effects in chemical freeze-out
from double isotope yield ratios: THeLi (3,4He,6,7Li)(Albergo's formula) TBeLi (7,9Be,6,8Li)
C. Sfienti et al., PRL 102 (2009)
issue:dynamical compound stabilityvs. fragmentation phase space
temperatures from SMM ensemble calculations
mean microcanonical temperatures
experimental isotope temperatures
densities from correlations
Au+Au 1 A GeV
S. Fritz et al., PLB 461 (1999)
without filter
ρ/ρ0 = 0.1 – 0.4
from radius of sphere andnumber of spectator nucleons
RAu=6.7 fm
R≈8 fm
R≈10 fm
R≈9.5 fm
p+p
densities from moving source fits Coulomb energies according to
the fission systematics for decaying nuclei of Z=79 and Z = 39
U. Milkau et al., PRC 44 (1991)
inclusive reactions on Au
density in dynamical approaches
SACA method identifies fragments at 60 fm/c and ρ/ρ0 ≈ 0.6
QMD with simulated annealing clusterization algorithm (Aichelin, Puri et al.)
figures from Vermani and Puri, EPL 85 (2009)60 fm/c
MSTSACA
ALADIN data
fragment modificationsfragment modifications
HodoCHodoCTT
ALADiALADiN N MagneMagnett
TP-MUSIC TP-MUSIC IVIV
TOF-TOF-WallWall
TargetTarget
LANDLAND
ALADiN experiment S254 Z resolutionZ resolution
A resolutionA resolution
C. Sfienti et al., PRL 102 (2009), R. Ogul et al., PRC 83 (2011)
main result: reduced symmetry energyof fragments in the hot environment;will affect neutron capture rates in SN
107Sn 124Sn
2m
Projectile fragmentation ofneutron-rich and neutron-poorprojectiles: 124Sn, 107Sn, 124La (1.14 ≤ N/Z)
SMM ensemble calculationsused for analysis
mass variation with excitationenergy taken into account;fixed to reproduce exclusive yields
Zbound = ΣZi with Zi≥2
A.S. Botvina, N. Buyukcizmeci, R. Ogul et al.
(SMM: Statistical Multifragmentation Model)
and model study of sensitivities
meant to reproduce participant-spectator geometry
Statistical Multifragmentation ModelSMM
standard modified
124Sn
124La
exp
exp
standard
standard
main result:neutron-rich fragment yields require low symmetry energy
R. Ogul et al., PRC 83 (2011)
Isoscaling:Experiment vs. SMM
experiment
surface alone
symmetry term reduced at chemical freeze-out
in multifragmentation reactions
2514 8
4
S. Bianchin,S. Bianchin, K. Kezzar, A. Le Fèvre, J. Lühning, J. K. Kezzar, A. Le Fèvre, J. Lühning, J. Lukasik, U. Lynen, W.F.J. Müller, H. Orth, A.N. Lukasik, U. Lynen, W.F.J. Müller, H. Orth, A.N.
Otte, H. Sann, C.Schwarz, C. Sfienti, W. Otte, H. Sann, C.Schwarz, C. Sfienti, W. Trautmann, J. Wiechula, M.Hellström, D. Henzlova, Trautmann, J. Wiechula, M.Hellström, D. Henzlova, K. Sümmerer, H. Weick, P.Adrich, T. Aumann, H. K. Sümmerer, H. Weick, P.Adrich, T. Aumann, H.
Emling, H. Johansson,Emling, H. Johansson, Y. Leifels, R. Palit, H. Simon, Y. Leifels, R. Palit, H. Simon, M. De Napoli, G. Imme', G.Raciti, E.Rapisarda, R. M. De Napoli, G. Imme', G.Raciti, E.Rapisarda, R. Bassini, C. Boiano, I. Iori, A. Pullia,Bassini, C. Boiano, I. Iori, A. Pullia, W.G.Lynch, M. W.G.Lynch, M.
Mocko, M.B. Tsang, G. Verde, M. Wallace, C.O. Mocko, M.B. Tsang, G. Verde, M. Wallace, C.O. Bacri, A. Lafriakh,Bacri, A. Lafriakh, A. Boudard, J-E. Ducret, A. Boudard, J-E. Ducret,
E.LeGentil, C. Volant, T. Barczyk, J. Brzychczyk, Z. E.LeGentil, C. Volant, T. Barczyk, J. Brzychczyk, Z. Majka, A. Wieloch, J. Cibor, B. Czech, P. Pawlowski, Majka, A. Wieloch, J. Cibor, B. Czech, P. Pawlowski, A. Mykulyak, B. Zwieglinski, A. Chbihi, J. Frankland A. Mykulyak, B. Zwieglinski, A. Chbihi, J. Frankland
and A.S. Botvinaand A.S. Botvina
memory of earlier stagesmemory of earlier stages
The largest fragment as order parameter
<MIMF>
percolation describes the partitions wellKreutz et al., Nucl. Phys. A556 (1993)
classical molecular dynamics
early fragment recognition and persistence
X. Campi et al., Phys. Rev. C 67, 044610 (2003)
Fermi motionFermi motion
Schüttauf et al., NPA 607, 457 (1996) Föhr et al., PRC 84, 054605 (2011)
prop.√ZT ≈ 15 MeV
momentum widths in projectile fragmentation
ALADIN and FRS at GSI
σ0 = 115 MeVT ≈ 14 MeV
T = 15 MeV expected for cold Au in the Goldhaber model
Odeh et al., PRL 84, 4557 (2000) with analysis following Bauer, PRC 51, 803 (1995)
prop.√ZT ≈ 15 MeV
kinetic temperatures in projectile fragmentation
interpreted within the „hot“ Goldhaber model of Bauer
Bauer‘s numerical solution for ρ/ρ0 = 1for ρ/ρ0 = 0.3
control of the compositioncontrol of the composition
ALADIN experiment S254
contour lines representlimiting temperatures followingtemperature dependentHartree-Fock calculationsusing Skyrme forces
N
Z
A=124
107Sn, 124La124Sn, 197Au
600 A MeV
"Mass and isospin effects in multifragmentation"secondary beams
from 142Nd
evaporation attractor line
R.J. Charity, PRC 58, 1073 (1998)
nuclear structure and memory effects
SMM ensemble calculations byA.S. Botvina,R. Ogul et al.
lines SMM
symbols exp
124Sn124La107Sn
ALADIN experiment S254
nuclear structure and memory effects
SMM ensemble calculations byA.S. Botvina,R. Ogul et al.
lines SMM
symbols exp
238U
56Fe
124Sn
107Sn124Sn124La107Sn
ALADIN experiment S254
U, Fe from FRS
SMM calculations with ensembles from ALADIN studyA/Z of the initial projectiles 2.24 vs. 2.48
112Sn + 112Sn124Sn + 124Sn
data: V. Föhr et al., PRC 84, 054605 (2011)analysis: H. Imal et al., arXiv:1403.4786 [nucl-th]
projectile fragmentation at 1 AGeV (FRS at GSI)
collaborationscollaborations
present outlook on FAIR
April 2014
INDRA at GSI
Systems: Au + Au 40 to 150 AMeVXe + Sn 50 to 250 AMeV C + Au 95 to 1800 AMeV
Z = 3 at 100 A MeV central
γβ
y
November 1997 – April 1999
INDRA at GSI
November 1997 – April 1999
Systems: Au + Au 40 to 150 AMeVXe + Sn 50 to 250 AMeV C + Au 95 to 1800 AMeV
γβ
y
Z = 3 at 100 A MeV peripheral
Invariant cross sections for Au + Au at peripheral impact parameters
From the Fermi to the relativistic domain
INDRA at GSI
summary of S254
1. secondary beams essential to enhance effects
2. small changes of global observables with N/Z important for isolating isospin effects
3. isotope distributions exhibit memory and structure effects
4. isoscaling obeyed with high accuracy; reduced symmetry term for hot fragments
5. N/Z dependence of nuclear caloric curve indicates phase-space driven instability rather than Coulomb instability
6. spectator neutron source with T=4 MeV,invariant with system N/Z.
summary of S254