Spin-alignment and g-factor measurement of the I(pi)=12(+) isomer in (192)Pb produced in the relativistic-energy fragmentation of a (238)U beam

M. Kmiecik , A. Maj , J. Gerl , G. Neyens , L. Atanasova , D. L. Balabanski , F. Becker , P. Bednarczyk , G. Benzoni , N. Blasi , A. Bracco , S. Brambilla , L. Caceres , F. Camera , M. Ciemala , F. C. L. Crespi , S. K. Chamoli , S. Chmel , J. M. Daugas (1) , P. Detistov , P. Doornenbal , G. Georgiev (2) , K. Gladnishki , M. Gorska , H. Grawe , J. Grebosz , M. Hass , R. Hoischen , G. Ilie , M. Ionescu-Bujor , J. Jolie , I. Kojuharov , A. Krasznahorkay , R. Kulessa , M. Lach , S. Lakshmi , S. Leoni , G. Lo Bianco , Radomira Lozeva (2) , K. H. Maier , S. Mallion , K. Mazurek , W. Meczynski , B. Million , D. Montanari , S. Myalski , C. Petrache , M. Pfutzner , S. Piétri , Z. Podolyak , W. Prokopowicz , D. Rudolph , N. Saito , T. R. Saito , A. Saltarelli , G. S. Simpson (3) , J. Styczen , N. Vermeulen , E. Werner-Malento , O. Wieland , H. Wollersheim , M. Zieblinski

1 DAM/DIF - DAM Île-de-France
2 CSNSM - Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse
3 ILL - Institut Laue-Langevin

The feasibility of measuring g-factors using the TDPAD method applied to high-energy, heavy fragmentation products is explored. The 2623 keV I(pi) = 12(+) isomer in (192)Pb with tau = 1.57 mu s has been produced using the fragmentation of a 1 A GeV (238)U beam. The results presented demonstrate for the first time that such heavy nuclei produced in a fragmentation reaction with a relativistic beam are sufficiently well spin-aligned. Moreover, the rather large value of the alignment, 28(10)% of the maximum possible, is preserved during the separation process allowing the determination of magnetic moments. The measured values of the lifetime, tau = 1.54(9) mu s, and the g-factor, g = -0.175(20), agree with the results of previous investigations using fusion-evaporation reactions.

Mots clés: GSI; NUCLEI; SEPARATORS; ISOTOPES; FISSION; MOMENTS; LISE

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

M. Kmiecik, A. Maj, J. Gerl, G. Neyens, L. Atanasova, et al.. Spin-alignment and g-factor measurement of the I(pi)=12(+) isomer in (192)Pb produced in the relativistic-energy fragmentation of a (238)U beam. European Physical Journal A, 2010, 45, pp.153-158. ⟨10.1140/epja/i2010-11003-4⟩. ⟨in2p3-00668268⟩