Implications of the first observation of $B\to K_1\gamma$

Abstract

Implications of the recent new measurements of $B\to K_1\gamma$ by Belle are examined. It is shown that the new branching ratio $\calB(B\to K_1(1270)\gamma)$ requires very large form factor compared to the theoretically predicted one. This is an opposite case to $B\to K^*\gamma$ where theory expected larger branching ratio. Possible origins of the discrepancy are discussed.