Extracting the depolarization coefficient DNN from data measured with a full acceptance detector

The spin transfer from vertically polarized beam protons to Λ or Σ hyperons of the associated strangeness production p→p→pK+Λ and p→p→pK0Σ+ is described with the depolarization coefficient DNN. As the polarization of the hyperons is determined by their weak decays, detectors, which have a large acceptance for the decay particles, are needed. In this paper a formula is derived, which describes the depolarization coefficient DNN by count rates of a 4π detector. It is shown that formulas, which are given in publications for detectors with restricted acceptance, are specific cases of this formula for a 4π detector.