New Measurement of Ab at the Z Resonance using a Vertex-Charge Technique

TL;DR

This paper reports a new measurement of the parity-violation parameter Ab at the Z resonance using a vertex-charge technique, based on data from polarized Z decays at the SLAC Linear Collider.

Contribution

It introduces a self-calibrating vertex-charge method for measuring Ab in hadronic Z decays, providing a new approach to determine parity violation parameters.

Findings

Measured Ab = 0.897 with statistical and systematic uncertainties.

Analyzed approximately 400,000 hadronic Z decays from 1996-1998.

Utilized a novel vertex-charge technique for flavor tagging.

Abstract

We present a new preliminary measurement of the parity-violation parameter Ab using a self-calibrating vertex-charge technique. In the SLD experiment we observe hadronic decays of polarized Z bosons produced in collisions between longitudinally polarized electrons and unpolarized positrons at the SLAC Linear Collider. A sample of bb events is selected using the topologically reconstructed mass of B hadrons. From out 1996-8 data sample of approximately 400,000 hadronic Z decays, we obtain Ab = 0.897 +/- 0.027 (stat) +0.036/-0.034 (syst).