Gemma L. Wilson - Louisiana State University/Argonne National Laboratory
Studying beta-delayed neutron emission with recoil-ion spectroscopy
Future date to be added as speakers confirmed.
Times are given as British Summer Time, UTC+1. iCal Link
Monday 17th August, 3pm BST
Excited-state g-factor measurements as a probe of emerging nuclear collectivity
Abstract: This talk will begin with an introduction to g-factor measurements and what they can tell us about nuclear structure. The focus will be on measurements of g factors of short-lived excited-states (non-isomeric states) by the transient-field and recoil in vacuum (RIV) methods. New data concerning the emergence of collectivity near 132Sn will be presented. Recent work on developing techniques and improving precision will be outlined, in particular how the time-differential (plunger) version of the RIV method can solve transient-field calibration problems, giving accurate independent g-factor measurements.
Steven W. Yates
Monday 24th August, 3pm BST
Probing the structure of the Ge nuclei with fast neutrons: Neutrinoless Double-Beta Decay and Shape Coexistence
At the University of Kentucky Accelerator Laboratory, we observed γ rays following inelastic scattering of fast neutrons from several candidates for neutrinoless double-beta decay (0νββ), with our recent measurements focusing on 76Ge , 136Xe , and other nuclei in these regions. From these measurements, low-lying excited states were characterized, 0+ states and their decays were identified, level lifetimes were measured with the Doppler-shift attenuation method, multipole mixing ratios were established, and transition probabilities were determined.
The rate of 0νββ is approximately the product of three factors: the known phase-
space factor for the emission of the two electrons, the effective Majorana mass of the electron neutrino, and a nuclear matrix element (NME) squared. The NMEs cannot be determined experimentally and, therefore, must be calculated from nuclear structure models. A focus of our recent measurements has been on providing detailed nuclear structure data to guide these model calculations in the Ge region, and a procedure for future work, which will lead to meaningful data for constraining calculations of NMEs, is suggested.
This material is based upon work supported by the U.S. National Science Foundation under grant no. PHY-1913028.
 S. Mukhopadhyay, et al., Phys. Rev. C 95, 014327 (2017).
 E.E. Peters, et al., Phys. Rev. C 98, 034302 (2018).
Please get in touch if you are interested in presenting