|Extracting the Eliashberg Function| A multitude of important
chemical, physical, and biological phenomena are driven by
violations of the Born-Oppenheimer approximation (BOA), which
decouples electronic from nuclear motion in quantum calculations
of solids. Recent advances in experimental techniques combined
with ever-growing theoretical capabilities now hold the promise
of presenting an unprecedented picture of these violations. By
means of high-resolution angle-resolved photoemission at the ALS
and theoretical calculations, a multi-institutional
collaboration that includes researchers from Oak Ridge National
Laboratory, the University of Tennessee, Stanford University,
and the ALS has obtained the first high-resolution spectroscopic
images of the specific vibrational modes that couple to a given
electronic state. Breakdown in the BOA results from low-energy
excitations of the electrons near the Fermi energy coupling with
vibrational excitations of the solid. The resulting vibronic
interactions are a necess