Measurement of the absolute branching fraction of $D^{+}\rightarrow\bar   K^0 e^{+}\nu_{e}$ via $\bar K^0\to\pi^0\pi^0$
  By analyzing 2.93 fb$^{-1}$ data collected at the center-of-mass energy $\sqrt s=3.773$ GeV with the BESIII detector, we measure the absolute branching fraction of the semileptonic decay $D^+\rightarrow\bar K^0 e^{+}\nu_{e}$ to be ${\mathcal B}(D^{+}\rightarrow\bar K^0 e^{+}\nu_{e})=(8.59 \pm 0.14 \pm 0.21)\%$ using $\bar K^0\to K^0_S\to \pi^0\pi^0$, where the first uncertainty is statistical and the second systematic. Our result is consistent with previous measurements within uncertainties. 
M. Ablikim, M. N. Achasov, X. C. Ai, O. Albayrak, M. Albrecht, D. J.   Ambrose, A. Amoroso, F. F. An, Q. An, J. Z. Bai, R. B...
hep-ex