Place: Nishina Hall (hybrid Zoom)
Date: Jun16 (Tue) 13:30 - 15:30
Speaker: Dr. Adrian Montes Plaza (CNS, UT)
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Title:
Triple shape coexistence in neutron-deficient Pb isotopes
Abstract:
Shape coexistence is a rising phenomenon that has become global within the nuclear chart over the past decades. In the vicinity of the neutron mid-shell N=104 lead region, collective intruder configurations give rise to oblate and prolate deformations that compete with the sphericity governing the ground states. However, the prediction of this phenomenon is still a great challenge for state-of-the-art theoretical calculations.
In this research, simultaneous gamma-ray and conversion-electron spectroscopy was combined with lifetime measurements in order to address the shape evolution near Pb-190. The nuclei of interest were produced via fusion-evaporation reactions during two separate experiments that were performed in the Accelerator Laboratory of the University of Jyväskylä (Finland). The combined analysis on Pb-190 led to report, for the first time, the direct measurement of three different deformations near the ground state in an atomic nucleus. In this seminar, neighbouring odd-mass Pb-189 and Pb-191 isotopes will also be discussed, for which a coherent picture based on the particle-core coupling scheme has been proposed.