title: Quantum anomaly in molecular physics.
abstract: The interaction of an electron with a polar molecule is shown to be the simplest realization of a quantum anomaly in a physical system. The existence of a critical dipole moment for electron capture and formation of anions, which has been confirmed experimentally and numerically, is derived. This phenomenon is a manifestation of the anomaly associated with quantum symmetry breaking of the classical scale invariance exhibited by the point-dipole interaction. Finally, analysis of symmetry breaking for this system is implemented within two different models: point dipole subject to an anomaly and finite dipole subject to explicit symmetry breaking.
authors.affiliation: Department of Physics, University of San Francisco, San Francisco, California 94117-1080, USA.
authors.forename: H E
authors.initials: HE
authors.lastname: Camblong
authors.forename: L N
authors.initials: LN
authors.lastname: Epele
authors.forename: H
authors.initials: H
authors.lastname: Fanchiotti
authors.forename: C A
authors.initials: CA
authors.lastname: García Canal