The Mass of a Spin Vortex in a Bose-Einstein Condensate

In contrast to charge vortices in a superfluid, spin vortices in a ferromagnetic condensate move inertially (if the condensate has zero magnetization along an axis). The mass of spin vortices depends on the spin-dependent interactions, and can be measured as a part of experiments on how spin vortices orbit one another. For Rb87 in a 1 micron thick trap m_v is about 10^-21 kg.