[en] Excited states of a quark-antiquark system: the χ_b particles or bottomonium states are investigated. These states form part of cascade processes from the Υ(2S) states which are produced by annihilation of electrons and positrons of sufficient energy. By observation of the final-state particles of these cascades (2 photons and 2 leptons) several characteristics of these χ_b states, i.e. mass and hadronic widths, can be determined which are predicted by quantum chromodynamics (QCD). The electron-positron storage ring DORIS 2 at DESY, Hamburg is used to produce the Υ(2S) states. From about 35 million events exactly 100 are selected. From the energies and angular correlations of the final photons the masses and the spins of the χ_b states are determined. From the numbers of observed events, after corrections for detector efficiency, the branching ratios are obtained. For the observed masses best agreement is found for models which base their asymptotic behaviour on QCD and assume the long range confining interaction to be effectively of the scalar type. The observed branching ratios are translated into hadronic widths. The results are in good agreement with corresponding QCD predictions. (Auth.)