| Experiment | Measurement | Reference |
|---|---|---|
| Belle | \([3.73 \pm 0.87\mbox{ (stat)} \pm 0.46\mbox{ (syst)} ^{+0.18}_{-0.08}\mbox{ (model)}] \times 10^{-4}\) | Experiment Note |
| Belle | < \(5.1 \times 10^{-4}\) | PLB 553, 159 (2003) |
| Average | \(\mathbf{[3.73 ^{+1.00}_{-0.99}\mbox{ (combined)}] \times 10^{-4}}\) |