Eur. Phys. J. A (2010) 43: 145-151
https://doi.org/10.1140/epja/i2010-10905-3

Regular Article - Experimental Physics

On the character of three 8⁺ states in ¹⁹²Pb

¹ Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, ACT 0200, Canberra, Australia
² Department of Physics, Australian National University, ACT 0200, Canberra, Australia
³ Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA

^* e-mail: Anna.Wilson@anu.edu.au

Received: 27 October 2009
Revised: 29 November 2009
Accepted: 2 December 2009
Published online: 9 January 2010

Abstract

Three low-lying 8⁺ states have been identified in ¹⁹²Pb . A newly observed cascade of -rays built directly on the 8⁺ ₁ state is compared to the previously identified, weakly rotational band above the 11^- i _13/2 , h _9/2 isomer in the same nucleus, and to analogous structures in ¹⁹⁴Pb . The similarity of all four structures lends support to the suggestion that the 8⁺ ₁ configurations are of a similar oblate deformation to the 11^- isomers. The excitation energies of all three 8⁺ states in ¹⁹²Pb and ¹⁹⁰Pb are compared to systematics. The possibility that one of the 8⁺ states in ¹⁹²Pb is associated with a prolate shape is discounted.