First Measurement of the Rate for the Inclusive Radiative Penguin Decay<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi mathvariant="italic">b</mml:mi><mml:mo>→</mml:mo><mml:mi mathvariant="italic">s</mml:mi><mml:mi mathvariant="italic">γ</mml:mi></mml:math>

We have measured the inclusive $b\ensuremath{\rightarrow}s\ensuremath{\gamma}$ branching ratio to be $(2.32\ifmmode\pm\else\textpm\fi{}0.57\ifmmode\pm\else\textpm\fi{}0.35)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, where the first error is statistical and the second is systematic. Upper and lower limits on the branching ratio, each at 95% C.L., are $B(b\ensuremath{\rightarrow}s\ensuremath{\gamma})&lt;4.2\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ and $B(b\ensuremath{\rightarrow}s\ensuremath{\gamma})&gt;1.0\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$. These limits restrict the parameters of extensions of the standard model.