concettina sfienti concettina sfienti, gsi darmstadt isotopic effects in spectator fragmentation at...
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Concettina Sfienti
Concettina Sfienti, GSI Darmstadt
Isotopic Effects in Spectator Fragmentation at Relativistic Energies
Gross Features and Isotopic Effects
Limiting Temperature
Isoscaling and the Symmetry Energy
Conclusion & Outlook
The ALADiN Recipe
Physics Motivation
NUFRA2007International Conference on Nuclear Fragmentation From Basic Research to ApplicationsSeptember 24 - October 1, 2007, Kemer (Antalya)
Concettina Sfienti
S.BianchinS.Bianchin, K.Kezzar, , K.Kezzar, A.Le FèvreA.Le Fèvre, J.Lühning , J.Lühning J.LukasikJ.Lukasik, U.Lynen, W.F.J. Müller, H.Orth, A.N.Otte, , U.Lynen, W.F.J. Müller, H.Orth, A.N.Otte,
H.Sann, H.Sann, C.SfientiC.Sfienti, C.Schwarz, A.Sokolov, , C.Schwarz, A.Sokolov, W.TrautmannW.Trautmann, J. Wiechula, M.Hellström, D.Henzlova, , J. Wiechula, M.Hellström, D.Henzlova,
K.Sümmerer, H.Weick, P.Adrich, T.Aumann, K.Sümmerer, H.Weick, P.Adrich, T.Aumann, H.Emling, Y.Leifels, R.Palit, H.Simon, H.Johansson, H.Emling, Y.Leifels, R.Palit, H.Simon, H.Johansson,
M.De NapoliM.De Napoli, G.Imme', G.Raciti, E.Rapisarda, , G.Imme', G.Raciti, E.Rapisarda, R.Bassini, C.Boiano,I.Iori, A.Pullia,R.Bassini, C.Boiano,I.Iori, A.Pullia, W.G.Lynch, W.G.Lynch,
M.Mocko, M.B.Tsang, M.Wallace, C.O.Bacri, M.Mocko, M.B.Tsang, M.Wallace, C.O.Bacri, A.Boudard, J-E.Ducret, A. Lafriakh, E.Le Gentil, A.Boudard, J-E.Ducret, A. Lafriakh, E.Le Gentil,
C.Volant, T. Barczyk, C.Volant, T. Barczyk, J.BrzychczykJ.Brzychczyk, J.Cibor, Z.Majka, , J.Cibor, Z.Majka, A.Mykulyak, A.Mykulyak, P.PawlowskiP.Pawlowski, A.Wieloch, B. Zwieglinski, , A.Wieloch, B. Zwieglinski,
B.Czech and B.Czech and A.S.BotvinaA.S.Botvina
Concettina Sfienti
… … study nuclear matter under extreme conditions of study nuclear matter under extreme conditions of density (high and low), temperature, size , isospin…density (high and low), temperature, size , isospin…
… … study nuclear matter under extreme conditions of study nuclear matter under extreme conditions of density (high and low), temperature, size , isospin…density (high and low), temperature, size , isospin…
Spectators can be heated !
Advantages of the Recipe
Typical Incident Energy 1 AGeV
(almost) no flow
Source well localized in rapidity
Equilibrated System
Easy 4 coverage for fragments
Disadvantages of the Recipe
Varying Size of the system by varying Excitation Energy.
Disadvantages: Typical Incident Energy 30AMeV Flowcentralcollision 0 Overlap Participant & Spectators
Physics Motivation
Concettina Sfienti
The ALADiN Program
UNIVERSALITY of Spectator Fragmentation
Physics Motivation
Concettina Sfienti
The ALADiN Caloric Curve
J. Besprosvany and S. Levit Phys. Lett B 217 (1989) 1
Proton rich nuclei: vanishing limiting temperatures
J.B. Natowitz et al., Phys.Rev. C 65 034618 (2002)
Physics Motivation
Concettina Sfienti
The ALADiN Spectrometer
HodoCHodoCTT
ALADiALADiN N MagneMagnett
TP-MUSIC TP-MUSIC IIIIII
TOF-TOF-WallWall
LANDLAND
TargetTarget
ALL Fragments (Z 2)
Isotope Resolution Protons...(but TOF)
124Sn,197Au,124La,107Sn
Einc = 600AMeV ( 1000 p/sec)
Secondary Beams Secondary Beams (Low Intensities!)(Low Intensities!)
The ALADiN Recipe
Concettina SfientiThe ALADiN Recipe
The ALADiN Spectrometer
0
213.0
m
ZR
A
Concettina SfientiGross Features and Isotopic Effects
124Sn
124La
107Sn
First N/Z Effects on Mass Spectra
Discriminant analysisJ. Łukasik et al., arXiv:0707.0598
Concettina Sfienti
Charge Partition
Gross Features and Isotopic Effects
Searching for N/Z effects in...
N/Z of light-mass fragmentsIsotopic RatiosNeutron Emission
Concettina SfientiGross Features and Isotopic Effects
N/Z Effects on Charge Partition
At low excitation energy neutron emission of
heavy residue suppressed for the
neutron-poor systems
Concettina Sfienti
ZZ )(
Properties of Hot Fragments
Gross Features and Isotopic Effects
Concettina Sfienti
R. Ogul and A.S. Botvina, PRC (2002)
B0 = 18 MeV
Gross Features and Isotopic Effects
Isotopic Inversion of Properties of Hot Fragments: the Surface term
Concettina Sfienti
A.S. Botvina et al., nucl-th/0606060
centrality
B = aV · A - aO · A2/3 - aC · Z2/A1/3 - aS · (A-2Z)2 / A + aP· δ / A1/2
Gross Features and Isotopic Effects
N/Z Dependence of the Surface Term
Concettina Sfienti
● ● ● SMM ensemble calculations for γ=14, preliminary
neutron initial(N/Z) projectile
(by P.Pawlowski)
Gross Features and Isotopic Effects
N/Z Effects on Neutrons Multiplicities
Concettina Sfienti
238U
56Fe
FRS data
FRS data
W.Trautmann, NN2006
124Sn
107Sn 238U124Sn
56Fe
107Sn
close to expectation for hot fragments
Z=8
Odd-Even Effects Structure effects Memory Effects They may cancel in scaling plots
Odd-Even Effects larger for the proton-rich systems Strongly bound even-even nuclei attract a large fraction of the product yield in the secondary stage
Gross Features and Isotopic Effects
Light Fragments (inclusive)
Concettina Sfienti
Odd-even effects
Gross Features and Isotopic Effects
Weak dependence on centrality
N. Buyukcizmeci et al, EPJA (2005)
Concettina Sfienti
Comparison with SMM
Gross Features and Isotopic Effects
Concettina SfientiLimiting Temperature
N/Z on Isotopic Ratios
extra yield in neutron poor case
Concettina SfientiLimiting Temperature
N/Z on Isotopic Temperatures
SmallSmall
Smallsmall
smallsmall
effects
Small
smallsmall
small
Concettina Sfienti
Isoscaling
Isoscaling and the Symmetry Energy
«systematic behavior of yield ratios following grandcanonical expectations»
T
)exp()()exp(),(
),(),(
p
1
212
T
ZNSZNCZNY
ZNYZNR
n
M.B. Tsang et al., PRC 64, 054615 (2001) M.B.Tsang et al. PRL123(2001)
Concettina SfientiIsoscaling and the Symmetry Energy
Isoscaling
Concettina SfientiIsoscaling and the Symmetry Energy
…from isoscaling to
22
22
21
214
A
Z
A
Z
Tn
p0 fit of individual Z fits
First experimental conclusion:The individual slopes are identical for Z≥3
Second experimental conclusion:The Isoscaling parameters continue to drop
Increase
in te
mpera
ture
does not c
ompensa
te
decrease
of
Concettina SfientiIsoscaling and the Symmetry Energy
Comparison with existing data….
A. Le Fevre et al., PRL 94(2005) 162701
D.V. Shetty et al.,
PRC 76(2007) 024606
Concettina Sfienti
22
22
21
214
A
Z
A
Z
Tn
Discussion (I)
S.Albergo et al. Il Nuovo Cimento A (1985)
T
Decrease in confirmed Apparent Saturation could depend on T
Concettina SfientiIsoscaling and the Symmetry Energy
22
22
21
214
A
Z
A
Z
Tn
Discussion (II)
22
22
21
21
A
Z
A
Z
A. Le Fèvre et al., PRL 94, 162701 (2005)
Concettina Sfienti
In the grand-canonical approximation:
22
22
21
21
2
1
21
2
1
4ln
expexpexp
A
Z
A
Z
Y
YT
TTY
Y
TY
n
n
nn
n
neutronneutron
Conclusion & Outlook
Concettina Sfienti
Isotopic Effects Global N/Z effects are small Isotope distributions exhibit memory and
structure effects Temperature invariant with N/Z in
contradiction to limiting temperature assumption
Isoscaling Isoscaling data extended into the
vaporization regime Reduced symmetry term at freeze-out
…something….
Conclusion & Outlook
What have we learnt?
Concettina SfientiConclusion & Outlook
…need to be answered…
•Why does the limiting temperature approximation seem to work so well for the masses but not for the isospin?
• Isoscaling...why does it work so well?
•Does really remain constant?
Unique Chance: NEUTRONS!
Concettina SfientiConclusion & Outlook
S.BianchinS.Bianchin, K.Kezzar, , K.Kezzar, A.Le FèvreA.Le Fèvre, J.Lühning , J.Lühning J.LukasikJ.Lukasik, U.Lynen, W.F.J. Müller, H.Orth, A.N.Otte, , U.Lynen, W.F.J. Müller, H.Orth, A.N.Otte,
H.Sann, H.Sann, C.SfientiC.Sfienti, C.Schwarz, A.Sokolov, , C.Schwarz, A.Sokolov, W.TrautmannW.Trautmann, J. Wiechula, M.Hellström, D.Henzlova, , J. Wiechula, M.Hellström, D.Henzlova,
K.Sümmerer, H.Weick, P.Adrich, T.Aumann, K.Sümmerer, H.Weick, P.Adrich, T.Aumann, H.Emling, Y.Leifels, R.Palit, H.Simon, H.Johansson, H.Emling, Y.Leifels, R.Palit, H.Simon, H.Johansson,
M.De NapoliM.De Napoli, G.Imme', G.Raciti, E.Rapisarda, , G.Imme', G.Raciti, E.Rapisarda, R.Bassini, C.Boiano,I.Iori, A.Pullia,R.Bassini, C.Boiano,I.Iori, A.Pullia, W.G.Lynch, W.G.Lynch,
M.Mocko, M.B.Tsang, M.Wallace, C.O.Bacri, M.Mocko, M.B.Tsang, M.Wallace, C.O.Bacri, A.Boudard, J-E.Ducret, A. Lafriakh, E.Le Gentil, A.Boudard, J-E.Ducret, A. Lafriakh, E.Le Gentil,
C.Volant, T. Barczyk, C.Volant, T. Barczyk, J.BrzychczykJ.Brzychczyk, J.Cibor, Z.Majka, , J.Cibor, Z.Majka, A.Mykulyak, A.Mykulyak, P.PawlowskiP.Pawlowski, A.Wieloch, B. Zwieglinski, , A.Wieloch, B. Zwieglinski,
B.Czech and B.Czech and A.S.BotvinaA.S.Botvina
Concettina SfientiConclusion & Outlook
...seems to...
Concettina Sfienti
PreAmpPreAmp
Anode wiresAnode wires
Resistive chargeResistive chargedivision readoutdivision readout
Pad readoutPad readoutin groupsin groups
12 mm pad modulo-five connected
Reduces the number of readout ch. from 80 to 17
Fine position determination from PAD readout Rough
position from charge-division method of the anode wires
Resolve the position ambiguity.
Anode & Pad Readout
The ALADiN Recipe