title: Effects of extreme magnetic quadrupole fields on penning traps and the consequences for antihydrogen trapping.
abstract: Measurements on electrons confined in a Penning trap show that extreme quadrupole fields destroy particle confinement. Much of the particle loss comes from the hitherto unrecognized ballistic transport of particles directly into the wall. The measurements scale to the parameter regime used by ATHENA and ATRAP to create antihydrogen, and suggest that quadrupoles cannot be used to trap antihydrogen.
authors.affiliation: Department of Physics, University of California at Berkeley, and the Lawrence Berkeley National Laboratory, Berkeley California 94720, USA.
authors.forename: J
authors.initials: J
authors.lastname: Fajans
authors.forename: W
authors.initials: W
authors.lastname: Bertsche
authors.forename: K
authors.initials: K
authors.lastname: Burke
authors.forename: S F
authors.initials: SF
authors.lastname: Chapman
authors.forename: D P
authors.initials: DP
authors.lastname: van der Werf