Confirmation of the Shears Mechanism in Near-Spherical Tin Nuclei

D. G. Jenkins; R. Wadsworth; J. A. Cameron; R. M. Clark; D. B. Fossan; I. M. Hibbert; V. P. Janzen; R. Krücken; G. J. Lane; I. Y. Lee; A. O. Macchiavelli; C. M. Parry; J. M. Sears; J. F. Smith; S. Frauendorf

doi:10.1103/PhysRevLett.83.500

Confirmation of the Shears Mechanism in Near-Spherical Tin Nuclei

D. G. Jenkins, R. Wadsworth, J. A. Cameron, R. M. Clark, D. B. Fossan, I. M. Hibbert, V. P. Janzen, R. Krücken, G. J. Lane, I. Y. Lee, A. O. Macchiavelli, C. M. Parry, J. M. Sears, J. F. Smith, and S. Frauendorf

Phys. Rev. Lett. 83, 500 – Published 19 July 1999

Abstract

Lifetimes of states of a magnetic dipole band in each of the nuclei $^{106, 108} Sn$ have been obtained using the Doppler shift attenuation method. The deduced $B (M 1)$ transition rates show the characteristic behavior associated with the shears mechanism. A simplified semiclassical analysis yields $B (M 1)$ values in qualitative agreement with those expected for previously assigned configurations. The results suggest extremely low deformations for these dipole structures. In particular, the $^{106} Sn$ band appears to be the first example of almost pure magnetic rotation in a spherical nucleus.

Received 2 February 1999

DOI:https://doi.org/10.1103/PhysRevLett.83.500

Authors & Affiliations

D. G. Jenkins¹, R. Wadsworth¹, J. A. Cameron², R. M. Clark³, D. B. Fossan⁴, I. M. Hibbert^1,*, V. P. Janzen⁵, R. Krücken^3,†, G. J. Lane^4,‡, I. Y. Lee³, A. O. Macchiavelli³, C. M. Parry¹, J. M. Sears⁴, J. F. Smith^4,§, and S. Frauendorf^6,∥

¹Department of Physics, University of York, Heslington, York Y01 5DD, United Kingdom
²Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada L85 4M1
³Lawrence Berkeley National Laboratory, Berkeley, California 94720
⁴Department of Physics, State University of New York at Stony Brook, Stony Brook, New York 11794-3800
⁵Chalk River Laboratories, AECL Research, Chalk River, Ontario, Canada K0J 1J0
⁶FZ Rossendorf, Postfach 510119, D-01314 Dresden, Germany

^*Present address: Dept. of Physics, University of Liverpool, Liverpool L69 7ZE, U.K.
^†Physics Department, Yale University, New Haven, CT 06520.
^‡Present address: Lawrence Berkeley National Laboratory, Berkeley, California 94720.
^§Present address: Schuster Laboratory, University of Manchester, Manchester M13 9PL, U.K..
^∥Present address: Dept. of Physics, University of Notre Dame, Notre Dame, IN 46556.