Using the CLEO~II detector we measure B(Ds+→ηe+ν)/B(Ds+→ϕe+ν)=1.24±0.12±0.15, B(Ds+→η′e+ν)/B(Ds+→ϕe+ν)=0.43±0.11±0.07 and B(Ds+→η′e+ν)/B(Ds+→ηe+ν)=0.35±0.09±0.07.
We find the vector to pseudoscalar ratio, B(Ds+→ϕe+ν)/B(Ds+→(η+η′)e+ν)=0.60±0.06±0.06, which is similar to the
ratio found in non strange D decays.Comment: 11 page uuencoded postscript file, postscript file also available
through http://w4.lns.cornell.edu/public/CLN
We study the mechanism of production of the light scalar mesons in the
Ds+→π+π−e+ν decays: Ds+→ssˉe+ν→[σ(600)+f0(980)]e+ν→π+π−e+ν, and compare it with the
mechanism of production of the light pseudoscalar mesons in the Ds+→(η/η′)e+ν decays: Ds+→ssˉe+ν→(η/η′)e+ν.
We show that the ssˉ→σ(600) transition is negligibly small in
comparison with the ssˉ→f0(980) one. As for the the f0(980) meson,
the intensity of the ssˉ→f0(980) transition makes near thirty percent
from the intensity of the ssˉ→ηs (ηs=ssˉ) transition. So,
the Ds+→π+π−e+ν decay supports the previous conclusions about a
dominant role of the four-quark components in the σ(600) and f0(980)
mesons.Comment: 8 pages, 3 figures, the variant matches the publication in Phys. Rev.
Recent semileptonic D meson decay results are summarized, including the
improved measurements of absolute branching fractions for exclusive D0
semileptonic decays into K−e+ν, π−e+ν and
K∗−e+ν, and the first observation and absolute branching fraction
measurement of D0→ρ−e+ν with the first CLEO-c data sample.Comment: 4 pages, 5 figures, submitted to the proceedings of ICHEP0
The decay KS0→πeν has been observed by the CMD-2 detector at
the e^+e^- collider VEPP-2M at Novosibirsk. Of 6 million produced KL0KS0
pairs, 75±13 events of the KS0→πeν decay were selected. The
corresponding branching ratio is B(KS0→πeν)=(7.2±1.4)×10−4. This result is consistent with the evaluation of B(KS0→πeν) from the KL0 semileptonic rate and KS0 lifetime
assuming ΔS=ΔQ .Comment: 7 pages, 6 figures, LaTex2e. Submitted to Phys.Lett.
The lowest-order expression for the partial W width to eν,Γ(W→eν)=GμMW3/(6π2), has no oblique radiative
corrections from new physics if the measured W mass is used. Here Gμ=(1.16639±0.00002)×10−5 GeV/c2 is the muon decay constant. For
the present value of MW=(80.14±0.27) GeV/c2, and with mt=140
GeV/c2, one expects Γ(W→eν)=(224.4±2.3) MeV. The total
width Γtot(W) is also expected to lack oblique corrections from
new physics, so that Γtot(W)/Γ(W→eν)=3+6[1+{αs(MW)/π}]. Present data are consistent with this prediction.Comment: 15 pages (LaTeX), one PostScript figure not included (available upon
request