Measurement of the Direct Photon Spectrum from theϒ(1S)

We have observed decays of the $\Upsilon \mathrm{}\left(1S\right)\mathrm{}$ into hadronic final states containing high-energy photons. These are interpreted as coming from the decay $\Upsilon \mathrm{}\left(1S\right)\mathrm{}\to \gamma +\mathrm{gluon}+\mathrm{gluon}$. We compare the shape of the observed photon energy spectrum with several theoretical predictions and deduce the value of the strong-coupling constant ${\alpha }_s$ and the QCD scale parameter ${\Lambda }_{\overline{\mathrm{MS}}}$ ($\overline{\mathrm{MS}}$ denotes the modified minimal-subtraction scheme) associated with each prediction.