Physical Review D 68,1 (2003) 011102;
We have searched for the baryon-containing radiative penguin decays B- -->Lambda(p) over bar gamma and B--->Sigma(0)(p) over bar gamma, using a sample of 9.7x10(6) B (B) over bar events collected at the Y(4S) with the CLEO detector. We find no evidence for either, and set 90% confidence level upper limits of B(B--->Lambda(p) over bar gamma)+0.3B(B--->Sigma(0)(p) over bar gamma)](Egamma)>2.0 GeV<3.3x10(-6), [B(B--->Sigma(0)(p) over bar gamma)+0.4B(B--->Lambda(p) over bar gamma)](Egamma)>2.0 GeV<6.4x10(-6). From the latter, we estimate B(B-->X(s)gamma,X-s containing baryons)(Egamma)>2.0 GeV<3.8x10(-5). This limit implies upper limits on corrections to CLEO's recent measurement of branching fraction, mean photon energy, and variance in photon energy from b-->sgamma that are less than half the combined statistical and systematic errors quoted on these quantities.
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