Observation of an electric quadrupole transition in a negative ion: Experiment and Theory

Abstract

The first direct experimental observation of an electric quadrupole ($\text{E}$2) transition between bound states of an atomic negative ion has been made. The transition was observed in the negative ion of bismuth by resonant (1+1) photodetachment from Bi${}^{-}$ ${}^3{\text{P}}_2$ via excitation of the Bi${}^{-}$ ${}^3{\text{P}}_0$ fine structure state. The $\text{E}$2 transition properties were independently calculated using a hybrid theoretical approach to account for the strong multi-level electron interactions and relativistic effects. The experimental and theoretical results are in excellent agreement, providing valuable new insights into this complex system and forbidden transitions in negative ions.

7 pages, 3 figures, 4 tables

References in corpus (5)

• Enhanced laboratory sensitivity to variation of the fine-structure constant using highly-charged ions
• Development of a configuration-interaction + all-order method for atomic calculations
• QED shifts in multivalent heavy ions
• Radiative rotational lifetimes and state-resolved relative detachment cross sections from photodetachment thermometry of molecular anions in a cryogenic storage ring
• Optical clocks based on the Cf${}^{15+}$ and Cf${}^{17+}$ ions