| Vol. 53,
No. 3 September 1999 pp. 463-468 Signature splitting in magnetic rotational bands AMITA, ASHOK K JAIN, ALPANA GOEL* and BALRAJ SINGH· Department of Physics,
University of Roorkee, Roorkee 247 667, India Abstract. Nearly-spherical nuclei in three mass regions have recently been observed to exhibit rotational-like features. We have identified almost 80 such bands; largest number (43) lie in the lead region. Most of these bands are assigned oblate multi-quasiparticle configurations. Their interpretation in terms of 'magnetic rotation' does not allow for signature splitting in these bands. We have however found signature splitting as well as signature inversion in many bands. We apply the two-quasiparticle plus rotor model to understand the occurrence of signature splitting vis-a-vis the role of 'shears mechanism' in these bands. Keywords. Magnetic rotation; shears mechanism; nearly spherical nuclei; signature splitting; Pb isotopes; particle rotor model. PACS Nos 21.60; 27.80+w |