title: Evidence for new isotopes of element 107: 266Bh and 267Bh
abstract: New neutron rich isotopes 267107Bh and 266107Bh were produced in bombardments of a 249Bk target with 117-MeV and 123-MeV 22Ne ions at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. Identification was made by observation of correlated alpha-particle decays between the Bh isotopes and their Db and Lr daughters using a rotating wheel system. 267Bh was produced with a cross section of approximately 70 pb and decays with a 17(+14)(-6) s half life by emission of alpha particles with an average energy of 8.83+/-0.03 MeV. One atom of 266Bh was observed, decaying within 1 s by emission of a 9.29-MeV alpha particle.
authors.affiliation: Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 and Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
authors.initials: PA
authors.lastname: Wilk
authors.initials: KE
authors.lastname: Gregorich
authors.initials: A
authors.lastname: Turler
authors.initials: CA
authors.lastname: Laue
authors.initials: R
authors.lastname: Eichler
authors.initials: V
authors.lastname: Ninov
authors.initials: JL
authors.lastname: Adams
authors.initials: UW
authors.lastname: Kirbach
authors.initials: MR
authors.lastname: Lane
authors.initials: DM
authors.lastname: Lee
authors.initials: JB
authors.lastname: Patin
authors.initials: DA
authors.lastname: Shaughnessy
authors.initials: DA
authors.lastname: Strellis
authors.initials: H
authors.lastname: Nitsche
authors.initials: DC
authors.lastname: Hoffman