  We study the problem of localization in Quantum Field Theory (QFT) from the
point of view of inertial and accelerated experimenters. We consider the
Newton-Wigner, the Algebraic Quantum Field Theory (AQFT) and the modal
localization schemes, which are, respectively, based on the orthogonality
condition for states localized in disjoint regions of space, on the algebraic
approach to QFT and on the representation of single particles as positive
frequency solution of the field equation. We show that only the AQFT scheme
obeys causality and physical invariance under diffeomorphisms.
  Then, we consider the nonrelativistic limit of quantum fields in the Rindler
frame. We demonstrate the convergence between the AQFT and the modal scheme and
we show the emergence of the Born notion of localization of states and
observables. Also, we study the scenario in which an experimenter prepares
states over a background vacuum by means of nonrelativistic local operators and
another experimenter carries out nonrelativistic local measurements in a
different region. We find that the independence between preparation of states
and measurements is not guaranteed when both experimenters are accelerated and
the background state is different from Rindler vacuum, or when one of the two
experimenters is inertial.
