Theory is presented for excitation of hybrid electric/magnetic (HEM) wake-field modes by passage of an electron drive bunch in a dielectric-lined cylindrical waveguide. The drive bunch is moving parallel to the waveguide axis, but is displaced by a radial increment r_0. Knowledge of the amplitudes of all HEM modes allows calculation of the transverse forces on a bunch or bunches that follow the displaced drive bunch. Approximate formulae for the transverse forces on a trailing bunch are given, valid in the limit of small r_0. These transverse forces can lead to beam instability, if cumulative transverse motion is significant on the time-scale of passage of the bunch through the accelerator module. Constructive interference can be present amongst TM_(0m) monopole modes that produce highly-peaked spatiotemporally-localized axial wake-fields, with peak fields at the locations of trailing bunches in a multi-bunch train. In this case, the spectrum of dipole (and higher order) HEM modes may not enjoy the same degree of constructive intereference, and may not have the same axial periodicity as the monopole modes. Further analytical and computational study is needed to determine the limitations that transverse wake fields may impose on a multi-bunch dielectric wake-field accelerator.
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