No Arabic abstract
Using 980.6 $rm fb^{-1}$ of data collected with the Belle detector operating at the KEKB asymmetric-energy $e^+e^-$ collider, we present a measurement of the branching fraction of the singly Cabibbo-suppressed decay $Lambda_c^+ to p omega$. A clear $Lambda_c^+$ signal is observed for $Lambda_c^+ to p omega$ with a statistical significance of 9.1 standard deviations, and we measure the ratio of branching fractions ${cal B}(Lambda_c^+ to p omega)/{cal B}(Lambda_c^+ to p K^- pi^+) = (1.32 pm 0.12 (rm stat) pm 0.10 (rm syst))times 10^{-2}$, from which we infer the branching fraction ${cal B}(Lambda_c^+ to p omega) = (8.27 pm 0.75 (rm stat) pm 0.62 (rm syst) pm 0.42 (rm ref))times 10^{-4}$. The first quoted uncertainty is statistical, the second systematic, and the third from the reference mode $Lambda_c^+ to p K^- pi^+$.
We report measurements of the branching fractions of singly Cabibbo-suppressed decays $Lambda_c^+ to p eta$ and $Lambda_c^+ to p pi^0$ using the full Belle data sample corresponding to an integrated luminosity of 980.6 $rm fb^{-1}$. The data were collected by the Belle detector at the KEKB $e^{+}$$e^{-}$ asymmetric-energy collider. A clear $Lambda_c^+$ signal is seen in the invariant mass distribution of $p eta$. The signal yield of the $Lambda_c^+ to p eta$ process is $7734 pm 263$; from this, we measure the ratio of branching fractions ${cal B}(Lambda_c^+ to p eta)/{cal B}(Lambda_c^+ to p K^- pi^+) = (2.258 pm 0. 077(rm stat. ) pm 0.136(rm syst. ))times 10^{-2}$, from which we infer the branching fraction ${cal B}(Lambda_c^+ to p eta) = (1.42 pm 0.05(rm stat.) pm 0.11(rm syst.)) times 10^{-3}$. In addition, no significant signal for $Lambda_c^+ to p pi^0$ is found so an upper limit on the branching fraction of ${cal B}(Lambda_c^+ to p pi^0)<8.0 times 10^{-5}$ at 90% credibility level is set, more than three times better than the best current upper limit.
We present the first model-independent measurement of the absolute branching fraction of the Lambda_c+ -> p K- pi+ decay using a data sample of 978 fb^-1 collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The number of Lambda_c+ baryons is determined by reconstructing the recoiling D(*)- anti-p pi+ system in events of the type e+e- -> D(*)- anti-p pi+ Lambda_c+. The branching fraction is measured to be Br(Lambda_c+ -> p K- pi+) = (6.84 +- 0.24^{+0.21}_{-0.27})%, where the first and second uncertainties are statistical and systematic, respectively.
We report the first measurement of the absolute branching fraction of the inclusive decay $Lambda_c^+ to K_S^0X$. The analysis is performed using an $e^+e^-$ collision data sample corresponding to an integrated luminosity of 567 pb$^{-1}$ taken at $sqrt{s}$ = 4.6 GeV with the BESIII detector. Using eleven Cabibbo-favored $bar{Lambda}_c^-$ decay modes and the double-tag technique, this absolute branching fraction is measured to be $mathcal{B}(Lambda_c^+ to K_S^0X)=(9.9pm0.6pm0.4)%$, where the first uncertainty is statistical and the second systematic. The relative deviation between the branching fractions for the inclusive decay and the observed exclusive decays is $(18.7pm8.3)%$, which indicates that there may be some unobserved decay modes with a neutron or excited baryons in the final state.
Using a data sample corresponding to an integrated luminosity of 567 pb$^{-1}$ collected at a center-of-mass energy of $sqrt{s}=4.6$ GeV with the BESIII detector, we measure the absolute branching fraction of the inclusive semileptonic $Lambda_c^+$ decay with a double-tag method. We obtain $mathcal{B}(Lambda_c^+ rightarrow X e^+ u_e) = (3.95pm0.34pm0.09)%$, where the first uncertainty is statistical and the second systematic. Using the known $Lambda_c^+$ lifetime and the charge-averaged semileptonic decay width of nonstrange charmed measons ($D^0$ and $D^+$), we obtain the ratio of the inclusive semileptonic decay widths $Gamma(Lambda_c^+ rightarrow X e^+ u_e)/bar{Gamma}(Drightarrow X e^+ u_e)= 1.26pm0.12$.