A new generation of calculations of light nuclei has deepened our understanding of nuclear structure. These sophisticated methods are constantly developing and precise measurements are necessary to challenge and refine the calculations. A wide variety of experimental tests are possible and a brief overview of these will be presented. A specific test involves inferring lifetimes through the slowing of nuclei in materials, the Doppler Shift Attenuation Method (DSAM) and improving the accuracy to a level where the electromagnetic matrix elements between excited states can provide useful constraints on modern calculations. An improved DSAM technique will be discussed which includes careful selection of the kinematic conditions for producing the states of interest, control of feeding from higher levels, improvements in gamma-ray detection, and better knowledge of how ions stop in materials. Each are important for moving far beyond the original measurements from the 1960's and improving both precision and accuracy. Results of experiments on ¹⁰Be and ¹⁰C will be presented and discussed in terms of recent ab-initio calculations.

Argonne Physics Division Colloquium Schedule