Measurements of $Z^0$ to Heavy-quark couplings at SLD

Masako Iwasaki; representing the SLD Collaboration

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arXiv · hep-ex/9905040

Measurements of $Z^0$ to Heavy-quark couplings at SLD

Masako Iwasaki·representing the SLD Collaboration

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Abstract

We present measurements of $Z^0$ to heavy-quark coupling electroweak parameters, $R_b$, $R_c$, and parity-violation parameter $A_c$, from SLD. The measurements are based on approximately 550k hadronic $Z^0$ events collected in 1993-98. Obtained preliminary results of $R_b$ and $R_c$ measurements are $R_b = 0.2159 \pm 0.0014 \pm 0.0014$ and $R_c = 0.1685 \pm 0.0047 \pm 0.0043$. In the $A_c$ measurement, we use four methods to determine the initial-quark charge: combined Kaon charge and Vertex charge, lepton, exclusively reconstructed D*, D-mesons, and a new method using inclusive soft-pion from D*. The preliminary results of these four methods were combined to give $A_c = 0.634 \pm 0.027$.

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Masako Iwasaki, representing the SLD Collaboration. 1999-05-22. Measurements of $Z^0$ to Heavy-quark couplings at SLD. https://arxiv.org/abs/hep-ex/9905040

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