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DPG Spring Meeting 2008 Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit Hilfe von a-Transfer-Reaktionen J. Leske1 B. Alikhani, L. Coquard, T. Bloch, N. Pietralla 1Institut für Kernphysik, TU Darmstadt A. Jungclaus, J. Walker, V. Modamio Universidad Autonoma de Madrid K.-H. Speidel Helmholtz-Institut für Strahlen- und Kernphysik, University of Bonn S. Pietri University of Surrey P. Doornenbal, J. Gerl, N. Goel, I. Kojouharov, W. Prokopowicz, H. Schaffner, H.-J. Wollersheim GSI, Darmstadt J. Cederkall, A. Ekstroem University of LUND R. Schwengner FZ Rossendorf R. Gernhäuser, P. Maier-Komor TU München Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Introduction & Motivation RIBF @ RIKEN (Japan) exploration of the entire nuclear landscape pn interaction nn force nuclear models need for radioactive ion beam facilities RISING @ GSI REX-ILSOLDE @ CERN (Europe) NSCL @ MSU (USA) ISAC @ TRIUMF (Canada) SPIRAL2 @ GANIL (France) Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Transient magnetic fields stable beam excited ion with aligned nuclear spin travels through polarized ferromagnetic environment polarized electrons and aligned nuclear spin empirical parametrization required ! linear parametrisation with ion beam induced attenuation F exp = Gbeam F lin g Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer g-factor measurements using a transfer Particle coincidence spectrum Particle-g- angular correlation Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Particle gated g-coincidence spectra two different nuclei studied simultaneously rates comparable those of Coulex experiments a transfer selective to low spin states Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer g factors and B(E2)‘s from a-transfer experiments 44 22 Ti 22 52 22 Ti 30 T1/2 = 60 y T1/2 = 1.7 m S. Schielke et al., Phys. Lett. B 567 (2003) 153 K.-H. Speidel et al., Phys. Lett. B 633 (2006) 219 62 30 Zn 32 T1/2 = 9.2 h 68 32 Ge36 T1/2 = 271 d O. Kenn et al., Phys. Rev. J. Leske et al., Phys. Rev. C65 (2002) 034308 C71 (2005) 044316 Is a transfer also applicable for isotopes heavier than A = 68 ? Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-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” excitation layer natural carbon 112,114,116Sn + 12C 4 Euroball Cluster at ±65° natC Gd Cu 112,114,116Sn* 116,118,120Te* 0.7 10.8 4.9 mg/cm2 112,114,116Sn recoil detection 20° 45° @ 4 MeV/u Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer UNILAC Experiment U234 2000 51o 65o 79o 10000 5000 25000 20000 12C Si spectrum 15000 counts 118Te 6+ → 4 + 15000 4+ → 2 + 2+ → 0+ 0 e-e+ 22+ → 2+ counts 3- → 2+ e-e+ 4000 2+ → 0+ 114Sn 5- → 4+ 6000 4+ → 2+ Prompt particle gated g-ray spectra 10000 a 5000 0 400 600 800 Eg (keV) 1000 0 1200 500 1400 1000 1500 2000 2500 3000 channel Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer g spectra 3000 e-e+ 2000 112Sn/116Te 1000 0 e-e+ 114Sn/118Te counts 4000 2000 0 6000 e-e+ 4000 116Sn/120Te 2000 0 200 400 600 800 1000 1200 1400 Eg (keV) Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Experimental Result (preliminary) g(2 +1) factors in 116,118,120Te lifetimes from DSAM analysis in 116,118,120Te PRELIMINARY P. Raghavan, At. Data Tables 42, 189 (1989) Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Summary a Transfer observed in nuclei beyond A ~ 110 Proof of principle for g-factor and DSAM experiments using a transfer to stable nuclei in a mass region between 32 < A < 116 a Transfer to stable Ion Beams (examples) Beam : 78Kr 86Kr 84Sr 96Ru Isotope : 82Sr 90Sr 88Zr 100Pd T1/2 : 48 25.5 d 83.4 d 3.6 d 44 52 28.5 y 54 124Xe 136Xe 128Ba 140Ba 72 2.4 d 84 12.8 d More exotic nuclei by a Transfer to radioactive Ion Beams ! Institut für Kernphysik, TU Darmstadt Kernstrukturuntersuchungen an radioaktiven Isotopen mit a-Transfer Outlook Plunger Experiments AGATA-Demonstrator (Legnaro) Precision lifetime study in the proton-rich 100Pd following Coulomb-barrier a-transfer reactions on 96Ru Precision lifetime study in the neutronrich 140Ba following Coulomb-barrier atransfer reactions on 136Xe 1 symmetric cluster (prototype) 4 asymmetric cluster 36-fold segmented Ge cristalls 540 segments, 555 channels (digital) photopeak efficiency 3 – 8 % Transient Field & DSAM Experiments UNILAC (GSI), Legnaro, REX-ISOLDE, GANIL Institut für Kernphysik, TU Darmstadt