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W A Wenzel

Publications and source records attributed to W A Wenzel.

114 records · Page 7Linked to original sources
PubMed2001

Measurement of the decays B--> phiK and B--> phiK*.

We have observed the decays B--> phiK and phiK(*) in a sample of over 45 million B mesons collected with the BABAR detector at the PEP-II collider. The measured branching fractions are B(B+--> phiK+) = (7.7(+1.6)(-1.4)+/-0.8)x10(-6), B(B0--> phiK0) = (8.1(+3.1)(-2.5)+/-0.8)x10(-6), B(B+--> phiK(*+)) = (9.7(+4.2)(-3.4)+/-1.7)x10(-6), and B(B0--> phiK(*0)) = (8.7(+2.5)(-2.1)+/-1.1)x10(-6). We also report the upper limit B(B+--> phipi(+))<1.4x10(-6) ( 90% C.L.).

Journal Article↗
PubMed2001

Observation of CP violation in the B(0) meson system.

We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of Upsilon(4S) decays collected in 2001, bringing the data available to 32 x 10(6) BB macro pairs. We select events in which one neutral B meson is fully reconstructed in a final state containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2 beta, is derived from the decay time distributions in such events. The result sin2 beta = 0.59+/-0.14(stat)+/-0.05(syst) establishes CP violation in the B(0) meson system. We also determine absolute value of lambda = 0.93+/-0.09(stat)+/-0.03(syst), consistent with no direct CP violation.

Journal Article↗
PubMed2001

Measurement of CP-violating asymmetries in B0 decays to CP eigenstates.

We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP eigenstate containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the standard model is proportional to sin2beta, is derived from the decay time distributions in such events. The result is sin2beta = 0.34+/-0.20 (stat)+/-0.05 (syst).

Journal Article↗
PubMed1991

Reported measles immunisation and serological immunity in children attending general practitioners.

To determine the feasibility of serological testing for measles immunity in children attending general practitioners and to assess the validity of establishing immune status by reported immunisation history compared with serology, a cross-sectional descriptive study was conducted in general practices in the Illawarra area south of Sydney, New South Wales. Participants were 234 children under 15 years attending general practitioners. 87 per cent of children were reported to have been immunised against measles, but 46 per cent of these children were seronegative for measles antibody using an ELISA test on finger-prick blood. This could not be explained by inaccurate reporting of immunisation. No causes other than failure to seroconvert or inadequate specificity of the test on the blood samples were evident. Failure to seroconvert as a result of inadequate adherence to cold chain requirements is a possibility that needs further investigation. The results further question whether a single vaccination is adequate to achieve the public health aims of measles immunisation programs.

Adolescent↗
PubMed1991

Involving general practitioners in public health initiatives--an increasing role.

Two community studies of campaigns conducted in the Illawarra Area of New South Wales demonstrate how GPs can successfully participate in structured public health initiatives. This approach is felt to bring benefits to the patient, the participating GP, and the wider community, and serves as a model for increased involvement in such programmes.

Australia↗