title: Ring dark solitons and vortex necklaces in Bose-Einstein condensates.
abstract: We introduce the concept of ring dark solitons in Bose-Einstein condensates. We show that relatively shallow rings are not subject to the snake instability, but a deeper ring splits into a robust ringlike cluster of vortex pairs, which performs oscillations in the radial and azimuthal directions, following the dynamics of the original ring soliton.
authors.affiliation: Department of Physics, University of Athens, Panepistimiopolis, Zografos, Athens 15784, Greece.
authors.forename: G
authors.initials: G
authors.lastname: Theocharis
authors.forename: D J
authors.initials: DJ
authors.lastname: Frantzeskakis
authors.forename: P G
authors.initials: PG
authors.lastname: Kevrekidis
authors.forename: B A
authors.initials: BA
authors.lastname: Malomed
authors.forename: Yuri S
authors.initials: YS
authors.lastname: Kivshar