Combined SLD Measurement of Ab at the Z Resonance using Various Techniques

TL;DR

This paper reports a combined measurement of the parity-violation parameter Ab at the Z resonance using multiple experimental techniques involving b-quark event selection and various tagging methods, resulting in a precise combined value.

Contribution

It introduces a new combined analysis of Ab measurements from different techniques, accounting for correlations, to improve precision of the parity-violation parameter.

Findings

Combined Ab value: 0.905 +/- 0.017 (stat) +/- 0.020 (syst)

Multiple techniques yield consistent results

Enhanced precision in measuring parity violation at the Z resonance

Abstract

We present a new preliminary combination of measurements of the parity-violation parameter Ab made by the SLD collaboration using various experimental techniques. The techniques differ in detail, but in general a sample of bb events is selected or enhanced by using the topologically reconstructed mass of the separated vertices formed by decaying B hadrons. The direction of the b(bbar) quark is signed by one of four final state tags: jet charge, vertex charge, leptons, or identified K+- from the b vertex. We account for statistical and systematic correlations between the four analyses to arrive at our combined result: Ab=0.905 +/- 0.017 {stat} +/- 0.020 (syst).