title: Measurement of a long electronic spin relaxation time of cesium atoms in superfluid helium.
abstract: The longitudinal electronic spin relaxation time of Cs atoms optically polarized in superfluid helium (He II, 1.5 K) has been measured with special care to cope with a serious decrease in the number of Cs atoms in the observation region. This decrease, mainly caused by helium convection in introducing the atoms into He II by laser sputtering, was significantly reduced using a new atom implantation method. Combined with a careful correction for the number of atoms, we have determined the relaxation time to be 2.24(19) s or longer, roughly twice as long as that in solid He.
authors.affiliation: Department of Physics, Graduate School of Science, Osaka University, Osaka 560-0043, Japan. take@valk.phys.sci.osaka-u.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Furukawa
authors.forename: Y
authors.initials: Y
authors.lastname: Matsuo
authors.forename: A
authors.initials: A
authors.lastname: Hatakeyama
authors.forename: Y
authors.initials: Y
authors.lastname: Fukuyama
authors.forename: T
authors.initials: T
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Izumi
authors.forename: T
authors.initials: T
authors.lastname: Shimoda