Search for time-dependent B0s - B0s-bar oscillations using a vertex charge dipole technique

TL;DR

This paper reports a search for B0s - B0s-bar oscillations using a large dataset from Z0 decays, employing a vertex charge dipole technique and beam polarization to identify oscillation frequencies.

Contribution

The study introduces a novel vertex charge dipole method combined with beam polarization to improve B0s oscillation measurements.

Findings

Excluded oscillation frequencies below 4.9 ps-1

Excluded frequencies between 7.9 and 10.3 ps-1

Demonstrated effective vertex reconstruction with CCD detectors

Abstract

We report a search for B0s - B0s-bar oscillations using a sample of 400,000 hadronic Z0 decays collected by the SLD experiment. The analysis takes advantage of the electron beam polarization as well as information from the hemisphere opposite that of the reconstructed B decay to tag the B production flavor. The excellent resolution provided by the pixel CCD vertex detector is exploited to cleanly reconstruct both B and cascade D decay vertices, and tag the B decay flavor from the charge difference between them. We exclude the following values of the B0s - B0s-bar oscillation frequency: Delta m_s < 4.9 ps-1 and 7.9 < Delta m_s < 10.3 ps-1 at the 95% confidence level.