A search for jet handedness in hadronic Z{sup 0} decays

Abstract

Transport of polarization through hadronization process is one of the fundamental interest in Quantum Chromodynamics which is a theory of strong interactions. In the low energy region where the hadronization occurs, QCD calculations are difficult, therefore at present the transport can be investigated experimentally. In this study the authors have searched for signatures of polarization of quarks and antiquarks in hadronic jets from Z{sup 0} {yields} q{bar q} decays. The polarization of quarks and antiquark produced by Z{sup 0} decays are predicted by the Standard Model of elementary particle physics. The authors defined several quantities depending on {open_quotes}jet handedness{close_quotes} methods and studied the correlation between the predicted polarization and the quantities. The signal was estimated by analyzing power which represents degree of the polarization transport through the hadronization process. The Z{sup 0} decays were measured by SLC Large Detector and the polarized electron beam provided by SLAC Linear Collider was useful for this study. The data from the 1993 run showed no signature of the transport of quark and antiquark polarization. Upper limits on magnitude of the analyzing power were set in the range 0.05-0.15 depending on the methods.