  We develop and analyze a theoretical model which yields the shifts and widths
of Feshbach resonances in an atomic waveguide. It is based on a multichannel
approach for confinement-induced resonances (CIRs) and atomic transitions in
the waveguides in the multimode regime. We replace in this scheme the
single-channel scalar interatomic interaction by the four-channel tensorial
potential modeling resonances of broad, narrow and overlapping character
according to the two-channel parametrization of A.D.Lange et al. As an input
the experimentally known parameters of Feshbach resonances in the absence of
the waveguide are used. We calculate the shifts and widths of s-, d- and g-wave
magnetic Feshbach resonances of Cs atoms emerging in harmonic waveguides as
CIRs and resonant enhancement of the transmission at zeros of the free space
scattering length. We have found the linear dependence of the width of the
resonance on the longitudinal atomic momentum and quadratic dependence on the
waiveguide width. Our model opens novel possibilities for quantitative studies
of the scattering processes in ultracold atomic gases in waveguides beyond the
framework of s-wave resonant scattering.
