We present the first model-independent measurement of the absolute branching fraction of the ${\mathrm{\Lambda }}_c^{+}\to p{K}^{-}{\pi }^{+}$ decay using a data sample of $978{\mathrm{fb}}^{-1}$ collected with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The number of ${\mathrm{\Lambda }}_c^{+}$ baryons is determined by reconstructing the recoiling $D^{(*)-}\overline{p}{\pi }^{+}$ system in events of the type $e^{+}{e}^{-}\to D^{(*)-}\overline{p}{\pi }^{+}{\mathrm{\Lambda }}_c^{+}$. The branching fraction is measured to be $\mathcal{B}({\mathrm{\Lambda }}_c^{+}\to p{K}^{-}{\pi }^{+})=(6.84\pm {0.24}_{-0.27}^{+0.21})\%$, where the first and second uncertainties are statistical and systematic, respectively.

• Received 30 December 2013

DOI:https://doi.org/10.1103/PhysRevLett.113.042002