Institut für Kernphysik, TU Darmstadt K.-H. Speidel Kernstrukturuntersuchungen an radioaktiven...

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Institut für Kernphysik, TU Darmstadt

K.-H. Speidel

Kernstrukturuntersuchungen an

radioaktiven Isotopen mit Hilfe von

-Transfer-Reaktionen

University of Surrey

DPG Spring Meeting 2008Darmstadt

J. Leske1

Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn

S. Pietri

GSI, Darmstadt

P. Doornenbal, J. Gerl, N. Goel, I. Kojouharov, W. Prokopowicz,

H. Schaffner, H.-J. Wollersheim

University of LUNDJ. Cederkall, A. Ekstroem

FZ RossendorfR. Schwengner

TU MünchenR. Gernhäuser, P. Maier-Komor

A. Jungclaus, J. Walker, V. ModamioUniversidad Autonoma de Madrid

1Institut für Kernphysik, TU DarmstadtB. Alikhani, L. Coquard, T. Bloch, N. Pietralla

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

need for radioactive ion beam facilities

Introduction & Motivation

exploration of the entire nuclear landscape

pn interaction

nn force

nuclear models

RIBF @ RIKEN (Japan)

NSCL @ MSU (USA)

ISAC @ TRIUMF (Canada)

SPIRAL2 @ GANIL (France)

REX-ILSOLDE @ CERN (Europe)

RISING @ GSI

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

Transient magnetic fields

linear parametrisation with

ion beam induced attenuation

exp = Gbeam

lin g

polarized electrons and aligned nuclear spin

excited ion with aligned nuclear spin travels through polarized ferromagnetic environment

empirical parametrization required !

stable beam

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

g-factor measurements using transfer

Particle coincidence

spectrum

Particle-- angular correlation

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

Particle gated -coincidence spectra

two different nuclei studied simultaneouslyrates comparable those of Coulex experiments

transfer selective to low spin states

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

g factors and B(E2)‘s from -transfer experiments

Ge68

32 36Zn62

30 32Ti44

22 22Ti52

22 30

O. Kenn et al., Phys. Rev. C65 (2002) 034308

J. Leske et al., Phys. Rev. C71 (2005) 044316

K.-H. Speidel et al., Phys. Lett. B 633 (2006) 219

S. Schielke et al., Phys. Lett. B 567 (2003) 153

T1/2 = 9.2 h T1/2 = 271 d

T1/2 = 1.7 m

T1/2 = 60 y

Is transfer also applicable for isotopes heavier than A = 68 ?

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

UNILAC Experiment U234 (see also HK 48.7 from J. Walker)

“Measurement of the g-factors of 2+ states in stable A=112,114,116 Sn isotopes using the transient field technique”

recoil detection20° 45°

4 Euroball Cluster at ±65°

112,114,116Sn@ 4 MeV/u

natC

Gd Cu

0.7 10.8mg/cm2

4.9

excitation layer natural carbon

112,114,116Sn + 12C112,114,116Sn*116,118,120Te*

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

UNILAC Experiment U234

400 600 800 1000 1200 14000

5000

10000

15000

0

2000

4000

6000

118Te

114Sn

Prompt particle gated -ray spectra

500 1000 1500 2000 2500 30000

5000

10000

15000

20000

25000

12C

Si spectrum

channel

coun

ts

E (keV)

coun

ts

51o

65o

79o

4+ →

2+

2+ →

0+

3- → 2

+

5- → 4

+

e- e+

2+ →

0+

4+ →

2+

2 2+ →

2+

e- e+

6+ →

4+

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

spectra

200 400 600 800 1000 1200 14000

2000

4000

60000

2000

4000

0

1000

2000

3000

E (keV)

coun

ts

112Sn/116Te

114Sn/118Te

116Sn/120Te e- e+

e- e+

e- e+

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

Experimental Result (preliminary)

PRELIMINARY

g(2 ) factors in 116,118,120Te+1 lifetimes from DSAM

analysis in 116,118,120Te

P. Raghavan, At. Data Tables 42, 189 (1989)

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

Summary

Beam :Isotope :

T1/2 :

78Kr82Sr44

86Kr90Sr52

84Sr88Zr48

124Xe128Ba72

136Xe140Ba84

96Ru100Pd54

3.6 d25.5 d 28.5 y 83.4 d 2.4 d 12.8 d

Transfer to stable Ion Beams (examples)

Transfer observed in nuclei beyond A ~ 110Proof of principle for g-factor and DSAM experiments using transfer to stable nuclei in a mass region between 32 < A < 116

More exotic nuclei by Transfer to radioactive Ion Beams !

Institut für Kernphysik, TU Darmstadt

Kernstrukturuntersuchungen an radioaktiven Isotopen mit Kernstrukturuntersuchungen an radioaktiven Isotopen mit -Transfer -Transfer

Outlook

Plunger Experiments

Precision lifetime study in the proton-rich 100Pd following Coulomb-barrier -transfer reactions on 96Ru

Precision lifetime study in the neutron-rich 140Ba following Coulomb-barrier -transfer reactions on 136Xe

1 symmetric cluster (prototype)

4 asymmetric cluster

36-fold segmented Ge cristalls

540 segments, 555 channels (digital)

photopeak efficiency 3 – 8 %

AGATA-Demonstrator (Legnaro)

Transient Field & DSAM Experiments

UNILAC (GSI), Legnaro, REX-ISOLDE, GANIL