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arXiv · 1406.1315

Effect of atomic electric quadrupole moment on positron binding

C. Harabati·V. A. Dzuba·V. V. Flambaum
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Abstract

Effect of the electric quadrupole moment, $Q$, is studied for positron-atom bound systems. It is demonstrated that for $Q >50$ a.u. the electric quadrupole potential is sufficiently strong to bind positron (or electron) even in the absence of the dipole polarization potential. Such large values of $Q$ are not known for atomic ground states, however, they exist in molecules and excited atoms. In the state $2s2p~^3P^o_2$ of beryllium, the quadrupole contribution makes difference between stable bound state and decay to Be$^+$ ion and positronium. In a majority of atoms the quadrupole contribution is small and can be neglected.

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C. Harabati, V. A. Dzuba, V. V. Flambaum. 2014-06-05. Effect of atomic electric quadrupole moment on positron binding. https://doi.org/10.1103/physreva.90.014501

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