  We study solitary waves of polarization (magnetic solitons) in a
two-component Bose gas with slightly unequal repulsive intra- and interspin
interactions. In experimentally relevant conditions we obtain an analytical
solution which reveals that the width and the velocity of magnetic solitons are
explicitly related to the spin healing length and the spin sound velocity of
the Bose mixture, respectively. We calculate the profiles, the energy and the
effective mass of the solitons in the absence of external fields and
investigate their oscillation in a harmonic trap where the oscillation period
is calculated as a function of the oscillation amplitude. The stability of
magnetic solitons in two dimensions and the conditions for their experimental
observation are also briefly discussed.
