High-Resolution Laser Spectroscopy for Nuclear-Structure Studies

Transcription

1 Collinear Laser ISOLDE High-Resolution Laser Spectroscopy for Nuclear-Structure Studies D. T. Yordanov 1, D. L. Balabanski 2, M. L. Bissell 3, K. Blaum 1, I. Budinčević 3, B. Cheal 4, M. De Rydt 3, K. T. Flanagan 4, N. Frömmgen 5, R. F. Garcia Ruiz 3, G. Georgiev 6, Ch. Geppert 5,7, M. Hammen 5, H. Heylen 3, M. Kowalska 8, K. Kreim 1, A. Krieger 5, R. Neugart 5, G. Neyens 3, W. Nörtershäuser 5,9, J. Papuga 3, M. M. Rajabali 3, R. Sánchez 10, S. Schmidt 9 1 Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, Heidelberg, Germany 2 INRNE, Bulgarian Academy of Science, BG-1784 Sofia, Bulgaria 3 Instituut voor Kern- en Stralingsfysica, KU Leuven, B-3001 Leuven, Belgium 4 School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK 5 Institut für Kernchemie, Universität Mainz, D Mainz, Germany 6 CSNSM-IN2P3-CNRS, Université de Paris Sud, F Orsay, France 7 Helmholtz Institute Mainz, D Mainz, Germany 8 Organisation Européenne pour la Recherche Nucléaire, CH-1211 Geneva 23, Switzerland 9 GSI Helmholtzzentrum für Schwerionenforschung GmbH, D Darmstadt, Germany

2 Nuclear chart 21 st century laser spectroscopy at ISOLDE/CERN Cd The Shell Model Z N h 82 1h 9/ s 2d 1g 50 1h 11/2 3s 1/2 2d 3/2 2d 5/2 1g 7/ g 9/2 50

3 Nuclear chart st century laser spectroscopy at ISOLDE/CERN 82 Monopole migration Cu Ga The Shell Model 2 Z 8 2 N 8 20 Be Li Halo nuclei 28 Na Ne K Ca Magicity Island of inversion Mg 50 2p 1f 2s 1d 1p 1s g 9/2 2p 1/2 1f 5/2 2p 3/2 1f 7/2 1d 3/2 2s 1d 5/2 1p 1/2 1p 3/2 1s

4 Collinear Laser ISOLDE Outline Cadmium: Physics interest Laser spectroscopy with bunched beams Frequency quadrupling Shell structure from m and Q moments Preliminary results Potassium: Inversion and reinversion of states Charge radii Isomer vs. g.s. in 38 K

5 Physics case - Cd Survey of ground-state properties in the Sn region ground and isomeric state properties of Cd 100 Sn 132 Sn rp process r process more accurate theoretical lifetimes of the N=82 isotones below 129 Ag shell quenching vs. deformation shell effect in the radii

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7 Experimental technique Bunched-beam fluorescence accumulation COLLAPS 1.) ion beam; 2.) laser; 3.) deflection plates; 4.) post acceleration; 5.) optical detection release T 1 ISCOOL - ISOLDE RFQCB T 2 T 1 / 10 4

8 Experimental technique Bunched-beam fluorescence 5p 2 P 1/2 Cd ion 5p 2 P 3/2 accumulation D 1 D 2 release 5s 2 S 1/2 T 1 ISCOOL - ISOLDE RFQCB T 2 T 1 / 10 4

9 Laser system for 215nm

10 # counts Experimental results - Cd Discovery of a long-lived isomeric state in 129 Cd I. II. III. 129 Cd g.s. + isomer Isotope shift relative to 114 Cd

11 # counts Experimental results - Cd Discovery of a long-lived isomeric state in 129 Cd I. II. III. 129 Cd, (11/2 - ) Isotope shift relative to 114 Cd

12 # counts Experimental results - Cd Discovery of a long-lived isomeric state in 129 Cd I. II. III. 129 Cd, 3/2 + Isotope shift relative to 114 Cd

13 Experimental results - Cd 11/2 - states: extreme shell-model view 2j+1-2n j n Q j n = j Q j 2j-1 h 11/2 3/2 + Phys. Rev. Lett., 110, (2013)

14 Experimental results - Cd 11/2 - states: extreme shell-model view 3/2 + 1/2 + h 11/2 Phys. Rev. Lett., 110, (2013)

15 # of counts Experimental results - K Reinversion from 1/2 + to 3/2 + between 49 K and 51 K 49 K, I = 1/2 51 K, I = 3/2 frequency (MHz) J. Papuga et al., Phys. Rev. Lett., 110, (2013)

16 # of counts Experimental results - K Zero spin for the odd - odd 50 K Frequency (MHz) K. Kreim et al., Phys. Lett. B, 731, 97 (2014)

17 Experimental results - K Z dependence of the N=28 kink K. Kreim et al., Phys. Lett. B, 731, 97 (2014)

18 # of counts Experimental results - K Isomer vs. g.s. in the self conjugate 38 K 38 K (g), I p = K (m), I p = 0 + Frequency relative to g.s. (MHz) M. L. Bissell et al., Phys. Rev. Lett., 113, (2014)

19 d<r 2 > 38g,A (fm) Experimental results - K Isomer vs. g.s. in the self conjugate 38 K ground state isomer A M. L. Bissell et al., Phys. Rev. Lett., 113, (2014)

20 Collinear Laser ISOLDE Summary Cadmium: Measured model independent I, m, Q and r 2 of Cd First direct observation of long-lived isomers in 127, 129 Cd Linear behavior of the h 11/2 Q moments in Cd Core polarization from magnetic moments Potassium: Reinversion from 1/2 + to 3/2 + between 49 K and 51 K Strong Z dependence of the N=28 kink 0 + isomer larger than the 3 + g.s. in the self conjugate 38 K IAP