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[en] For a class of hindered magnetic-dipole (M1) transition processes, such as Υ(3S)→ηb+γ (the discovery channel of the ηb meson), the emitted photon is rather energetic so that the traditional approaches based on multipole expansion may be invalidated. We propose that a 'hard-scattering' picture, somewhat analogous to the pion electromagnetic form factor at large momentum transfer, may be more plausible to describe such types of transition processes. We work out a simple factorization formula at lowest order in the strong coupling constant, which involves convolution of the Schroedinger wave functions of quarkonia with a perturbatively calculable part induced by exchange of one semihard gluon between quark and antiquark. This formula, without any freely adjustable parameters, is found to agree with the measured rate of Υ(3S)→ηb+γ rather well, and can also reasonably account for other recently measured hindered M1 transition rates. The branching fractions of Υ(4S)→ηb(')+γ are also predicted.