| Experiment | Measurement | Reference |
|---|---|---|
| Belle | \([6.8 \pm 0.7\mbox{ (stat)} \pm 1.3\mbox{ (syst)} \pm 0.3\mbox{ (model)}] \times 10^{-4}\) | PRD 69, 112002(2004) |
| BaBar | \([0.59 \pm 0.03\mbox{ (stat)} \pm 0.11\mbox{ (syst)}] \times 10^{-3}\) | Experiment Note |
| Average | \(\mathbf{[6.2 \pm 0.9\mbox{ (combined)}] \times 10^{-4}}\) |