Study of baryonic decays of B mesons at $BABAR$

Abstract

We report on recent $BABAR$ analyses of the baryonic $B$ decays ${\bar{B}}^0\to {\Lambda }_{\mathrm{c}}^{+}\bar{p}{\pi }^{+}{\pi }^{-}$, $B^{-}\to {\Sigma }_{\mathrm{c}}^{++}\bar{p}{\pi }^{-}{\pi }^{-}$, ${\bar{B}}^0\to {\Lambda }_{\mathrm{c}}^{+}\bar{p}p\bar{p}$ and ${\bar{B}}^0\to D^0\Lambda \bar{\Lambda }$. The used data sample contains $471\times 10^{6}B\bar{B}$ pairs that were generated in the process $e^{+}{e}^{-}\to {\rm Y}(4S)\to B\bar{B}$ and collected with the $BABAR$ detector at the PEP-II storage ring at SLAC. We find $\mathcal{B}({\bar{B}}^0\to {\Lambda }_{\mathrm{c}}^{+}\bar{p}{\pi }^{+}{\pi }^{-})=(12.3\pm 0.5_{\mathrm{stat}}\pm 0.7_{\mathrm{syst}}\pm 3.2_{{\mathrm{\Lambda }}_{\mathrm{c}}})\times 10^{-3}$, $\mathcal{B}(B^{-}\to {\Sigma }_{\mathrm{c}}^{++}\bar{p}{\pi }^{-}{\pi }^{-})=(2.98\pm 0.16_{\mathrm{stat}}\pm 0.15_{\mathrm{syst}}\pm 0.77_{{\mathrm{\Lambda }}_{\mathrm{c}}})\times 10^{-3}$, where the last uncertainty is due to $\mathcal{B}({\Lambda }_{\mathrm{c}}^{+}\to p{K}^{-}{\pi }^{+})$, respectively. For the decay ${\bar{B}}^0\to {\Lambda }_{\mathrm{c}}^{+}\bar{p}p\bar{p}$ we see no events and set an upper limit $\mathcal{B}({\bar{B}}^0\to {\Lambda }_{\mathrm{c}}^{+}\bar{p}p\bar{p})\times \frac{\mathcal{B}({\Lambda }_{\mathrm{c}}^{+}\to p{K}^{-}{\pi }^{+})}{0.050}<2.8\times 10^{-6}$ at $90\%$ CL, where we have normalized $\mathcal{B}({\Lambda }_{\mathrm{c}}^{+}\to p{K}^{-}{\pi }^{+})$ to the world average value. There is evidence for the decay ${\bar{B}}^0\to D^0\Lambda \bar{\Lambda }$ and we measure $\mathcal{B}({\bar{B}}^0\to D^0\Lambda \bar{\Lambda })=(9.8_{-2.6}^{+2.9}{}_{\mathrm{stat}}\pm 1.9_{\mathrm{syst}})\times 10^{-6}$ corresponding to a significance of $3.4\sigma$.

arXiv comment6 pages, 6 figures, Proceedings of Hadron2013