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Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski

Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences. 781 A.D. Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski

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Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski

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  1. Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  2. 781 A.D. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  3. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  4. Nuclear moments and structure of isomers in regions far from stability Dimiter L. Balabanski Institute for Nuclear Research and Nuclear Energy Bulgarian Academy of Sciences • basic definitions • experiments with fast beams • orientation in fragmentation reactions • how to approach ground state moments of exotic nuclei • how to approach isomeric states • how to approach short-lived states • what can we learn from such measurements • outlook • experiments with post-accelerated ISOL beams Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  5. 193Pb key issue: week exotic excitations e.g. magnetic rotation + 6 more pages Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  6. 128Cs key issue: week exotic excitations e.g. chiral rotation Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  7. N = 40 Z = 28 Q,  Q,  key issue: shell structure away from stability Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  8. A schematic view of the basic methods of producing radioactive nuclear beams. At the top we see the ISOL method with and without a post-accelerator. Below we see the In-flight method and the proposed hybrid in which fragments are caught in a gas cell and then re-accelerated. Accelerator Thick production target Beam manipulation Beam manipulation Post-accelerator Separator Accelerator Gas stopper Thin production target Separator Accelerator Fragment separator • The European perspective: • present day • ISOL: ISOLDE • in-flight: GSI, GANIL • post-accelerated ISOL: • REX-ISOLDE • near future • in-flight: FAIR • post-accelerated ISOL: • Spiral2, HIE-ISOLDE • far future: EURISOL ISOL post-accelerator ISOL ISOL ISOL trap Experiments In-flight In-flight post-accelerator In-Flight Experiments Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  9. Spin-oriented beams magnetic moment () quadrupole moment (Q) single-particle configuration (configuration mixing) collective properties (deformation, effective charges) Nuclear moment measurements Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  10. spin-alignment m -2 –1 0 +1 +2 spin-polarization m -2 –1 0 +1 +2 some definitions Spin-aligned and spin-polarized beams Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  11. m(I) = <I, m=I| | I,m=I>  = gl.l + gs.s m(j=l + 1/2) = m(j=l-1/2) = some more definitions Magnetic dipole moment in atomic nuclei • orbital momentum of the protons • intrinsic spin of the nucleons  = <j, m=j | z | j,m=j> Schmidt lines Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  12. odd proton odd neutron j = l – 1/2 j = l + 1/2   j = l – 1/2 j = l + 1/2 j j Schmidt lines Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  13. = . Q = Q(j) = yet more definitions Electric quadrupole moment in atomic nuclei Q = Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  14. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  15. experimental approach Basic principles for moment measurements (ground states) requirement:polarization of the spin ensemble electric quadrupole moments: interaction with external electric fields, e.g. with a lattice field after implantation magnetic dipole moments: experiments in external magnetic fields signal for -decaying ground states: GT -decay asymmetry (-NMR, -NQR) see talk of A.Yoshimi Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  16. Time Differential Perturbed Angular Distribution Measure Larmor precesion and decay I(t) B  J Fragment beam L = -gNB/h Field UP Field DOWN detectors at ±45° and ±135° time 2A2B2 the relative phases depend on the g-factor 2L t=0 time isomeric sates (ns −s) requirement:alignment of of the spin ensemble signal : time dependence of the intensity of the decay  rays TDPAD Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  17. YIELD 61Fe 61Fe 61Fe 61Fe +6.2(7)% ALIGNMENT(%) -15.9(8)% GENERAL ASPECTS of g-factor measurements with fast beams 4. FEASIBILITY: SPIN-ALIGNMENT ! PROJECTILE FRAGMENTATION + selection in longitudinal momentum (slits in FRS or via ion-correlation) CONDITION: STRIPPED FRAGMENTS ! Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  18. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  19. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  20. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  21. 67Ni 9/2+ 313 5/2+ 694 1/2- T1/2 = 13.3 ms Fourrier spectrum Amplitude 15 10 20 5 25 0 2 wL (Mrad/s) R(t) autocorrelation ms 1 2 3 4 5 G. Georgiev et al. J.Phys. G 28, 2993 (2002) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  22. 76Ge @ 130 MeV/u; 9Be target A1900 – 90% beam purity Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  23. I. Matea et al. PRL 93 (2004) 142503 Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  24. GANIL did a press release on this result ! Time-differential perturbed angular distributions principle investigators: Micha Hass (Rehovot) and Jean-Michel Daugas (Bruyeres-la-Chatel) test case 61Fe exp. July 2005 Q(61mFe; g9/2) =41(6) mb 2 = - 0.21 or +0.24 207 keV M1 transition 654 keV M2 transition Analysis: Nele Vermuelen, Leuven and Chamoli, Rehovot (PR C 75, 051302) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  25. (d,p) reaction, Tandem-ALTO, Orsay Qs(61Fe; 9/2+)= 41(6); 2 > 0 Qs(65Cu; 3/2−) = −19.5(4); 2 < 0 Qadd = QQ = 21.5(60) efm2 Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  26. I=2 ensemble classical view quantum-mechanical view m =2 m =-2 m =1 m =-1 m =0 I = 2 Population E Necessary to induce polarization of the beam prior the measurement ISOL beams Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  27. 65Zn 67Zn P P 100Tc 102Tc 64Cu 66Cu 65Cu 100Mo 63Cu 98Mo 99Mo 101Mo G. Georgiev (Orsay, France) and D.L. Balabanski (INRNE – BAS, Sofia) Electromagnetic moments in transfer reactions • populate low-spin (single-particle) states • go a step further in the Nuclear Terra Exotica Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  28. beams: 63,65Cu targets: 62,64Ni 3.5 MeV/u S2 detector of TIARA Cu-beam D2 target electromagnet What do we want to do next ? T1/2 = 20ns test case: g = +0.177(5) use particle –  coincidences instead of beam pulsing Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  29. inverse kinematics 63Cu beam @ 220 MeV (3.5 MeV/u) CD2target (2 mg/cm2) Ni ferromagnetic backing (15 µm) permanent magnet for holding field Particle identification: Si strip detector (8 annular strips) as ECsI 16 sectors – as E detector angular coverage 25° - 60° Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  30. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  31. Particle detection with TIARA (in collaboration with Surrey, Birmingham) The CD detector of TIARA The CsI detector Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  32. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  33. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  34. Particle-g vs. beam pulsing Very preliminary!! Try to avoid the particle- correlations if not absolutely necessary Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  35. requirement:alignment of of the spin ensemble short-lived (ps) states Transient field technique signal: rotation of the angular distribution of the  rays interaction:very high transient magnetic field (tens of Tesla) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  36. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  37. Honma et al., PR C 80, 064323 (2009) in the calculation f7/2 is frozen! Question: Is there deviation from the hydrodynamic limit? Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  38. 238U-fission at 750 MeV/u 136Xe-fagmentation at 700 MeV/u Sn g-RISING EXPERIMENTS performed Oct – Dec. 2005 • Spin-alignment in projectile fission and g-factors around 132Sn • (Gerda Neyens and Gary Simpson) 2. Spin-alignment and g-factors of isomers in 127,128Sn from fragmentation of a 136Xe beam. (Dimiter Balabanski and Michael Hass) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  39. Spin-alignedsecondary beam selected (S2 slits + position selection in SC21) SC41 gives t=0 signal for -decay time measurement Implantation: plexiglass degrader + 2 mm Cu (annealed) SC42 and SC43 validates the event THE EXPERIMENTAL SET-UP AT GSI: g-RISING Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  40. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  41. The 136Xe fragmentation experiment Z 127Sn analysis:L.Atanasova, Sofia A/q Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  42. 25% Isomeric ratio (arbitrary units) Position at Sc21 Momentum selection Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  43. 4.5(3) s 127Sn 128Sn J. Pinston et al., PRC 61, 024312 (2000) -ray spectra gated on 127Sn Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  44. N=82 1h11/2 3s1/2 2d3/2 2d5/2 1g7/2 Even Sn 5- nd3/2-1h11/2 -1 7-nd3/2-1h11/2 -1 10+h11/2 -2 N=50 Odd Sn 19/2+ nd3/2-1h11/2 -2 23/2+ nd3/2-1h11/2 -2 27/2-h11/2 -3 nh11/2 x 5-core nh11/2 x 7-core h11/2n, n=2,3 ms isomers in the Sn region Newly identified isomers ns1/2-1 Brown et al, PRC71 (2005) 044317 R. Lozeva, PR C 77, 064313 (2008) nd3/2-2 J. Pinston et al, PRC61 024312 (2000) , J. Pinston et al, JPG30 (2004) R57, NNDC data base and this work Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  45. Choice of the magnetic field B = 0.12 T g = - 0.15 3A sin(2wLt) R(t, ±B) = 4+A I1 = (A+L) + (D+G) I2 = (A+L) + (D+G) g = 0.16 Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  46. 715 keV 715 keV TDPAD 1095 keV FFT L. Atanasova, Europhys. Letters in preparation g = 0.17(2) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  47. G.Ilie et al, Phys. Lett. (submitted) g(7; 126Sn) = 0.097(3) g(10+; 128Sn) = 0.20(4) Analysis S.K. Chamoli; L. Atanasova et al, Europhys. Lett. (in preparation) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  48. 10+ 7 19/2+ 11/2 Sn neutron-rich isomers 7 :114,116Sn and 130Sn 10+ :116,118Sn 19/2+ : none Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  49. Structure of the 19/2+ isomer in 127Sn • the spin-parity assignment of the 19/2+ isomer is based on energy systematics • J. Pinston et al., PRC 61, 024312 (2000) • suggested configuration:(νh11/2 1 5)19/2+; gexp(h11/2) = 0.24 • the 5 isomers in even-even Sn isotopes take experimental values:gexp(5)  0.06 • and are understood as an admixture of (νh11/2 1d3/2 1)5- withgemp = 0.26 • (νh11/2 1s1/2 1)5- withgemp = 0.09 • for the structure of the 19/2+ isomer an admixture with the νg7/2 1h11/2 2 configuration is • suggested in order to explain the l -forbidden M2 isomer-decay transition. • gemp(νs1/2 1 h11/2 2) = 0.15 • gemp(νg7/2 1 h11/2 2) = 0.23 • the fragmentation g-RISING experiment yields gexp =  0.17(2) • LSSM calculations yieldgSM = 0.11 (calculation M.Hjorth-Jensen) Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

  50. The g-RISING collaboration: 71 researchers from 24 institutions 1. K.U. Leuven, Belgium: M. De Rydt, R. Lozeva, S. Mallion, G. Neyens, K. Turzó, N. Vermeulen 2. INRNE, Sofia, Bulgaria: D.L. Balabanski 3. University of Sofia, Bulgaria: L. Atanasova,P. Detistov 4. ILL Grenoble, France:G. Simpson 5. CEA, Bruyères le Chatel, France:J.M. Daugas, O. Perru 6. CSNSM – Orsay, France:G. Georgiev 7. ISKP Bonn, Germany: H. Hübel, S Chmel 8.GSI-Darmstadt, Germany:F. Becker, P. Bednarczyk, L. Caceres, P. Doornenbal, J. Gerl, H. Grawe, M. Górska, I. Kojuharov, N. Kurz, W. Prokopowicz, T. Saito, H. Schaffner, E. Werner-Malento, H.J. Wollersheim 9. IKP Koeln, Germany: J. Jolie, G. Illie,A. Blazhev 10. IKHP Rossendorf, Germany: R. Schwengner, G. Russev 11. ATOMKI, Debrecen, Hungary: A. Krasznahorkay 12. The Weizmann Institute, Israel:S. Chamoli, M. Hass, S. Lakshmi 13. University of Camerino, Italy: G. Lo Bianco, A. Saltarelli 14. LNL Legnaro, Italy: J.J. Valente-Dubon15. University of Milano, Italy: G. Benzoni, N. Blasi, A. Bracco, F. Camera, F. Crespi, D. Montanari, O. Wieland 16. U. Padova and INFN Padova, Italy: D. Bazzacco, E. Farnea17. INFN-Perugia, Italy:K. Gladnishki 18. IFJ-PAN Krakow, Poland:J. Grębosz, M. Kmiecik, A. Maj, K. Mazurek, W. Męczyński, S. Myalsky, J.Styczeń, M. Ziębliński 19. Jaggielonian University, Krakow, Poland: R. Kulessa 20. Warsaw University, Poland: M. Pfűtzner 21. NIPNE, Bucharest, Romania: M. Ionescu-Bujor, A. Iordachescu 22. Universidad Autonoma de Madrid, Spain: A. Jungclaus 23. Univerity of Lund, Sweden: C. Fahlander,R. Hoishen, D. Rudolf 24. University of Surrey, UK: Zs. Podolyàk, P. Regan, J. Walker, S. Pietri, C. Brandau. Physics of Nuclei at Extremes, T.I.Tech, 26.01.2010

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