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CEA Saclay CSNSM Orsay GANIL CaenIPN Orsay
Univ. SurreyCLRC DaresburyUniv. KeeleUniv. LiverpoolUniv. ManchesterUniv. PaisleyUniv. York
FZ JuelichFZ RossendorfGSI DarmstadtHMI BerlinTU/LMU MuenchenMPI HeidelbergTU DarmstadtUniv. BonnUniv. Koeln
KU Leuven
Univ. Milano INFN GenovaINFN LegnaroINFN/Univ. NapoliINFN/Univ. PadovaUniv. CamerinoUniv. Firenze
KTH StockholmUniv. LundUniv. Uppsala
NBI Copenhagen
IFJ KrakowIPJ SwierkUniv. KrakowUniv. Warszawa
Univ. Santiago de Compostela
Univ. MadridUniv. Valencia
IFIN, Bucharest
Nuclear Structure addressed at GSI/RISINGM.Górska, GSI Darmstadt
Rare Isotope Spectroscopic INvestigation at GSI: Oct. 2003-2009Rare Isotope Spectroscopic INvestigation at GSI: Oct. 2003-2009
Sofia, Bulgaria
rp-Process
Novae
and X-ray bursts
r-Process and Supernovae
Sp=0
Sn=0
RISING: Nuclear structure interestRISING: Nuclear structure interest
N=Z
Shell evolution/quenching
Isospin competition/symmetry
|Tz|=T =1: Iπ=0+
T=0 : Iπ=1+or (2j)+
Neutron numberPro
ton
num
ber
EXPERIMENTAL Features:EXPERIMENTAL Features:
- high energy beams >100MeV/u
- unambigous beam identification event by event
- cocktail or pure radioactive beam
- scattering experiments β~0.5:
coulomb excitation, knockout reaction
Ge array forward angles, εγ~5%
- stopped beam experiments:
isomers, beta and particle decay
Ge array spherical close geometry εγ~15%
First scattering experiments 2003-2005: Coulomb excitation,
One-, two-neutron knock-out
Ge Cluster
beam
Target chamber
CATE
RISING RISING -array for fast beams-array for fast beams
Ge Miniball
Typically: 100MeV/u, ε=0.06, ∆E/E=0.02
Relativistic Coulomb excitation of nuclei towards Relativistic Coulomb excitation of nuclei towards 100100SnSn
• 112,108Sn secondary beam with ~150MeV/u
• Au – Coulex target
A. Banu, PhD thesis, PR C72, 061305(R) (2005)A. Banu, PhD thesis, PR C72, 061305(R) (2005)
108Sn B(E2:2+→0+)EXP: 15.1 (3.3) W.u.TH1: 11.2 W.u. Morten Hjorth-JensenTH2: 11.5 W.u. Frederic Nowacki
2004: J. Cederkäll et al., REX-ISOLDE, 110Sn
2005: MSU, K.Starosta et al. 106-112Sn
asymmetry: p-h excitation? N=64 subshell closure?
M. Hjorth-Jensen, ν(d5/2g7/2s1/2h11/2), eν = 1e
2003
Sn chain: Enhanced Sn chain: Enhanced B(E2) systematics B(E2) systematics towards towards 100100SnSn
Shell Model: F. Nowacki et al., ν(d5/2g7/2s1/2h11/2), eν = 0.5e, π(g9/2g7/2d5/2d3/2s1/2), eπ = 1.5e
πν monopoles tuned toπESPEs and Z=50 shell gap
GSIRISING
P. Doornenbal et al., PRC(R) in print
A. Banu et al, PRC 72 061305(R) 2005
J. Cederkäll et al., PRL98, 172501(2007)
A. Ekström et al., PRL 101, 012502(2008)
C. Vaman et al., PRL 99, 162501(2007),
• A,Z event-by-event ID
• Time correlation ns - min
• Rate < 1 ion/hour
• Alignment → g, Q moment
+
• prompt flash
• isomeric ratio
• ray sequence
• spin-parity assignment
- + -
RISING: Stopped beamsRISING: Stopped beamsConvenor: P. H. Regan, University of SurreyConvenor: P. H. Regan, University of Surrey
100Sn
56Ni
132Sn
208Pb
62Ga
86Tc, 82Nb
54Ni, 50Fe108Zr
130Cd, 131In
204Pt, 205Au
Isomer scans
Decay measurementP. H. Regan
D. Rudolph
A. Gadea, A.Algora
B. Rubio, J. Fujita, W. Gelletly
T. Faestermann
A. Bruce
A. Jungclaus, M. Pfutzner, M.Gorska
P.H. Regan, J. Benliure, Zs. Podolyak
Zs. Podolyak
A. Blazhev, B. Wadsworth, P. Boutachkov, Zh. Liu
N=Z
N>Z
TechniquesTechniques – – Z vs A/Q plotZ vs A/Q plot Preliminary!!Preliminary!!
Prelim estimate > 2000 96Cd ions
Z
A/Q →
96Cd
B. Wadsworth et al.,
rp-proc
waiting
point
Expected
Known
Paestum 2003
9848Cd50
10050Sn50
Core excited states in large scale shell model
A. Blazhev et al., PRC 69, 064304 (2004)
V.I.Isakov, K.I. Erokhina Phys.At.Nucl.No.8,1431(2002).
F. Nowacki, priv. comm..
rp process path rp process path● @ T < 109 Kelvin when photodisintegration lifts (p,) – (,p) equilibrium
● MED of several 100 keV will influence the proton capture appreciably
• End of rp path near 100Sn due to fast decay beyond the double shell closure @Z=N=50
• 100Sn shell structure decisive for ß+/EC decay (Gamow-Teller) and waiting points
From:
H. Grawe, K. Langanke, G. Martínez-Pinedo, Rep.Progr.Phys. 70,1525 (2007)
M1 conversion
M1
E2
Decay scheme
(shell model)
Decay scheme
M. Karny et al. EPJA 27, 129 (2006)
100,102Sn ß+/EC decay
I = 6+ isomerism
1472
1969+1969
10049In 51
10249In53
10050Sn50
10250Sn52GT
GT
Particle identification spectrumParticle identification spectrum
100Sn
T.Faestermann et al.
In
Sn
Te
Sb
Cd
Ag
Pd
Rh
Ru
100Sn setting
T.Faestermann analysis: K.Eppinger, C.Hinke, TU München
Gamow-Teller decay in 100Sn
100100Sn setting check : Sn setting check : 9898CdCd
0+
8+
6+
4+
2+
0
1395
208322812428
12+ 6635
147
198
688
1395
4207s.e.
d.e.
new!?!
Langanke, K. & Martínez-Pinedo, G. Rev. Mod. Phys. 75, 819-862 (2003)
2+:Kautzsch, T. et al. Eur. Phys. J. A 9, 201-206 (2000)
Dillman et al., PRL, 91, 162503 (2003)
Astrophysics relevance for n-rich nuclei
204Pt
130Cd98Cd
70 72 74 76 78 80 820
500
1000
1500
60Nd
58Ce
56Ba
54Xe
52Te
48Cd
Ene
rgy
of 2
+ sta
te
Neutron number N
Indirect evidence for a N=82 shell quenchingIndirect evidence for a N=82 shell quenching
Kautzsch et al., Eur. Phys. J. A9 (2000) 201
indication from ß-decay studies at ISOLDE
Can the anomalous behaviour of 2+ energies in the Cd isotopestowards N=82 be attributed to a change in the N=82 shell gap ?
130130Cd from fission and fragmentationCd from fission and fragmentation
Lucia Caceres PhD theses Lucia Caceres PhD theses
A. Jungclaus et al., PRL 99, 132501 (2007)A. Jungclaus et al., PRL 99, 132501 (2007)
-coincidences130Cd
100100Sn vs Sn vs 132132SnSn N=50 TBME scaled by (88/132)1/3 to N=82 SPE from 99In and 131In, respectively
No dramatic shell quenching!No dramatic shell quenching!
B(E2) = 1.3(4) 1.45 (2.0) 1.2 1.1/1.3(2) WU
A. Blazhev et al., PRC 69, 064304 (2004) A. Jungclaus et al., PRL 99, 132501 (2007)A. Jungclaus et al., PRL 99, 132501 (2007)
(p1/2,g9/2)(s,d,g7/2,h11/2)
H. Grawe
Ir=27% Ir=13%
131131In spectraIn spectra131131In spectraIn spectra
M.G., L. Caceres et al., submitted to PLB
Z=49
E4: ≤1.6 2.4 WU
Shell model :
p 2p1/2,1g9/2,1g7/2,2d5/2
n 3s1/2,1h11/2,2d3/2,2f7/2,
(1h9/2)
1p1h excitations only !
132Sn single particle /
hole energies
Two-body interaction
from one major shell higher at 208Pb
PRC 44, 233 (1991)
scaled by A-1/3 and for
orbital overlap
N=82 gap at Cd:4.33 MeV vs. 4.94 MeV at Sn
More precisely...
The solar r-process abundance problem
The abundance deficiency (´´trough´´) is due to the changing slope in the neutron separation energy S2n (´´saddle point structure´´) in some mass formulae.
From: H. Grawe, K. Langanke, G. Martínez-Pinedo, Rep. Progr. Phys. 70,1525 (2007)
Depletion of progenitors !
´´trough´´
´´saddle point´´
Monopole evolution of the N=82 gapMonopole evolution of the N=82 gap
Shell quenching for very n-rich nuclei Shell quenching for very n-rich nuclei Potential shape: Wood Saxon (WS) Potential shape: Wood Saxon (WS) → Harmonic Oscillator (HO)→ Harmonic Oscillator (HO)
T.R. Werner, J. Dobaczewski, W. Nazarewicz, Z. Phys. A358 (1997) 169
stable nucleus
neutron rich
nucleus
need for intense radioactive nuclear beams
Conclusion:
● Fragmentation + fission of relativistic beams + FRS + RISING
● Precision spectroscopy of exotic nuclei → tuning of effective NN
interaction
● Monopoles determine shell evolution
● Nuclear structure and astrophysics
Future :
● FAIR + Super-FRS + HISPEC/DESPEC → intensity, acceptance,
efficiency, selectivity
● Modern effective NN interactions, SM techniquesNEUTRON DETECTOR
GE γ-ARRAY
RADIOACTIVEBEAM
HISPECHISPEC DESPECDESPEC
(fast, slow beams) (stopped beams)(fast, slow beams) (stopped beams)
Collaboration Collaboration A.Algora(Valencia), W.Gelletly(Surrey), A.Gadea (Legnaro), Y.Fujita(Osaka), B. Rubio(Valencia),
K.Langanke, G. Martinez-Pinedo, K. Sieja(GSI),
F. Nowacki (Strasbourg), P.Regan(Surrey), G. Neyens(KU Leuven),
H. Grawe (GSI), J. Tostevin (Surrey), P. Boutachkov(GSI), A. Blazhev (Köln),
T. Faesterman(Munich), B. Wadsworth(York), Zh. Liu(Edinburg), L.Caceres (GSI/Madrid), K. Eppinger, C. Hinke (TU Munich), F.G. Molina(Valencia),
A. Garnsworthy(Surrey/T), A. Banu(GSI), A. Jungclaus (Madrid),
M. Pfützner (Warsaw), Zs. Podolyak(Surrey), S. Pietri(Surrey/GSI),
P. Doornenbal(GSI/RIKEN), N.Brown(Köln), T. Brock (York),
S. Steer(Surrey), G. Farrelly(Surrey)
RISING/GSI group: H.J. Wollersheim, J.Gerl, P. Bednarczyk,
P. Boutachkov, C. Domingo, J. Grebosz, I. Kojoharov, H. Schaffner,
R. Hoischen(GSI/LUND)...
FRS group: H. Weick, H. Geissel, Y. Litvinov, Ch. Nociforo..
...and many others within the RISING collaboration