$K$-shell photodetachment of ${\mathrm{B}}^{-}$ has been measured using the collinear photon-ion beamline at the Advanced Light Source, Lawrence Berkeley National Laboratory, as well as calculated using two separate $R$-matrix methods. The measurement of the absolute photodetachment cross section, as a function of photon energy, exhibits three near-threshold shape resonances due to the ${}^{3}S$, ${}^{3}P$, and ${}^{3}D$ final partial waves. A fit to the measured data using three resonance profiles shows good overall qualitative agreement with the three partial wave cross sections calculated using either $R$-matrix method. However, certain significant and unresolved quantitative discrepancies exist between the experimentally inferred and the calculated resonance profiles.

• Received 28 November 2006

DOI:https://doi.org/10.1103/PhysRevA.76.032713