First Observation of the Decay $Ξ_{c}^{+} \to Ξ^{0} {e^{+} ν}_{e}$ and an Estimate of the $Ξ_{c}^{+}$ $Ξ_{c}^{0}$ Lifetime Ratio

Using the CLEO II detector at the Cornell Electron Storage Ring we have observed the decay modes

Ξ_{c}^{+} \to Ξ^{0} e^{+} ν_{e}

and

Ξ_{c}^{0} \to Ξ^{-} e^{+} ν_{e}

by the detection of a

Ξ

-positron pair of appropriate invariant mass. We find

B (Ξ_{c}^{+} \to Ξ^{0} e^{+} ν_{e}) σ (e^{+} e^{-} \to Ξ_{c}^{+} X) = 1.55 \pm 0.33 \pm 0.25

pb,

B (Ξ_{c}^{0} \to Ξ^{-} e^{+} ν_{e}) σ (e^{+} e^{-} \to Ξ_{c}^{0} X) = 0.63 \pm 0.12 \pm 0.10

pb,

B (Ξ_{c}^{+} \to Ξ^{-} π^{+} π^{+}) / B (Ξ_{c}^{+} \to Ξ^{0} e^{+} ν_{e}) = 0.44 \pm {0.11}_{- 0.06}^{+ 0.11}

, and

B (Ξ_{c}^{0} \to Ξ^{-} π^{+}) / B (Ξ_{c}^{0} \to Ξ^{-} e^{+} ν_{e}) = 0.32 \pm {0.10}_{- 0.03}^{+ 0.05}

. Assuming the

Ξ_{c}^{+}

and

Ξ_{c}^{0}

are equally produced in

e^{+} e^{-}

annihilation events at 10 GeV, the lifetime ratio of

Ξ_{c}^{+} / Ξ_{c}^{0}

is measured to be

2.46 \pm {0.70}_{- 0.23}^{+ 0.33}

This publication has 12 references indexed in Scilit:

First Observation of the Decay Ξc+→Ξ0e+νe and an Estimate of the Ξc+ Ξc0 Lifetime Ratio