Measurement of the cross sections for reaction π−p → Xo n in the momentum range up to 50 GeVc

The cross sections for the reaction π^?p → X^on, X^o → 2_λ are measured at 32.5 and $\text{48}\text{GeV}\text{c}$ momenta. The cross spectrometer of γ-quanta is used to select events of reaction, whose cross section is only about 0.05 μbarn. The cross section energy dependence has the power form ($\text{≈ p}{}^{\mathrm{?1.11\pm 0.12}}$. conclusion on U(6) symmetry of quark model is made when comparing the differential cross sections at zero angle for the reactions π^?p → X^o and π^?p → η^o. The angle of octet-singlet mixing for pseudo-scalar mesons β = ?(20.6 ± 2.2)° is defined.