| Experiment | Measurement | Reference |
|---|---|---|
| Belle | \([3.1 \pm 0.3\mbox{ (stat)} \pm 0.7\mbox{ (syst)}] \times 10^{-4}\) | PLB 634, 155 (2006) ( |
| BaBar | \([2.5 \pm 0.2\mbox{ (stat)} \pm 0.2\mbox{ (syst)}] \times 10^{-4}\) | PRL 102 132001 (2009) |
| Average | \(\mathbf{[2.6 \pm 0.3\mbox{ (combined)}] \times 10^{-4}}\) |