Neutron lifetime puzzle and neutron-mirror neutron oscillation

Standard Model, with its present precision, predicts the neutron -decay time SM=878.7 +/- 0.6s which is perfectly compatible with the neutron lifetime measured in the trap experiments trap=879.4 +/- 0.6s. However, the lifetime measured in the beam experiments via counting the protons produced by -decay npe e, beam=888 +/- 2.0 s, is deviated from SM by 9 seconds (4.4 sigma). This discrepancy can be explained via the neutron n conversion into mirror neutron n, its dark partner from parallel mirror sector. Provided that n and n have a tiny mass splitting approximate to 10-7eV, in magnetic fields of few Tesla used in beam experiments, n-n transition is resonantly enhanced converting a 1% fraction of neutrons into mirror neutrons which decay in invisible mode npe . Thus less protons are produced and the measured value beam appears larger than the true decay time tau(trap).