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arXiv · hep-ex/0505097

Search for the b --> d gamma process

The Belle Collaboration·D. Mohapatra
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Abstract

We report the results of a search for the flavor-changing neutral current process b --> d gamma using a sample of 275 million B meson pairs accumulated by the Belle detector at KEKB. We find no significant signal for the exclusive decays B- --> rho- gamma, B0B --> rho0 gamma, or B0B --> omega gamma. Assuming an isospin relation between the three modes, we set an upper limit for the combined branching fraction Br(B --> (rho,omega) gamma) < 1.4 x 10-6 at the 90% confidence level. This limit can be used to constrain the ratio of CKM matrix elements |Vtd/Vts|.

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The Belle Collaboration, D. Mohapatra. 2005-05-31. Search for the b --> d gamma process. https://doi.org/10.1103/physrevd.72.011101

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