title: Ionization potential of the helium atom.
abstract: The ground-state ionization potential of the He4 atom is found to be 5 945 204 223 (42) MHz. Along with lower-order contributions, this result includes all effects of relative order alpha4, alpha(3)m(e)/m(alpha), and alpha(5)ln(2)alpha. Effective operators derived in dimensionally regularized nonrelativistic quantum electrodynamics are employed. The average values of these operators are evaluated using a high-accuracy variational wave function constructed in an exponential basis.
authors.affiliation: Joint Institute for Nuclear Research, Dubna 141980, Russia. korobov@thsun1.jinr.ru
authors.forename: V
authors.initials: V
authors.lastname: Korobov
authors.forename: A
authors.initials: A
authors.lastname: Yelkhovsky