Particles and "bumps" in quantum field configurations

We study an approach to making a precise identification of particles with "bumps" in quantum field configurations. The problem requires some effort because typical field configurations are distributions and not elements of the classical configuration space at all. We show that the part of a configuration consisting of "vacuum fluctuations" may be identified and filtered out in a very natural way, leaving a function which is in the classical configuration space. The filtered field configuration depends on the state Ψ of the field, and for an n-particle state with n particles well localized and well separated in the Newton-Wigner sense, the filtered field configuration has n bumps located where the particles are. We close with a discussion of observation in the Schrödinger representation for the free field in terms of our results.