  A number of techniques are being developed to solve the monstrous sensitivity
gap that exists between the energy ranges of good sensitivity of the Compton
and of the pair telescopes and to extend polarimetry to the MeV gamma-ray
world. I characterize the properties of an active target, detailing the various
contributions to the angular resolution, using a full five-dimensional event
generator of the Bethe-Heitler differential cross section. With the same tool I
also examine the dilution of the polarization asymmetry induced by multiple
scattering in the conversion wafer.
