  Among some 400 million KsKl pairs produced in e+e- annihilations at DAFNE,
about 6500 each of Ks->pi+e-nubar and Ks->pi-e+nu decays have been observed
with the KLOE detector. From these, the ratio
G(Ks->pienu)/G(Ks->p+p-(g))=(10.19+-0.13)10-4 is obtained, improving the
accuracy on BR(Ks->pienu) by a factor of four and providing the most precise
test of the DeltaS=DeltaQ rule. From the partial width Gamma(Ks->pienu), a
value for f+(K0)Vus is obtained that is in agreement with unitarity of the
quark-mixing matrix. The lepton charge asymmetry AS=(1.5+-9.6stat+-2.9syst)10-3
is compatible with the requirements of CPT invariance. The form-factor slope
agrees with recent results from semileptonic Kl and K+ decays. These are the
first measurements of the charge asymmetry and form-factor slope for
semileptonic Ks decays.
