  The prospect of controlling entanglement in interacting quantum systems
offers a myriad of technological and scientific promises, given the progress in
experimental studies in systems such as ultracold trapped gases. This control
is often challenging because of decoherence, the process by which environmental
interactions create spurious entanglements that can destroy the desired
entanglement. Considering the collisional decoherence that is relevant for
quantum measurements utilizing scattering in one-dimensional trapped gases,
here we derive a relationship between particle masses and wave packet widths
that minimizes the entanglement created during scattering. We assess the
relevance of our results by directly observing this relationship in the
emergent scales of a master equation for a particle undergoing nonthermal
scattering. Our relationship is independent of the details of the particle
interactions and sheds light on how to design scattering processes that
minimize decoherence.
