Identified Hadron Production and Light Quark Fragmentation in

We have measured the differential cross sections for the production of π, K, K, K, φ, p, Λ and their corresponding antiparticles in separate samples of flavor-tagged Z → light-flavor (uū, dd̄, or ss̄), Z → cc̄ and Z → bb̄ events. Clear flavor dependences are observed, and the results are compared with the predictions of three fragmentation models. We have also performed a direct measurement of As, the parity-violating coupling of the Z 0 to strange quarks, by measuring the left-right-forward-backward production asymmetry in polar angle of the tagged s quark. Our preliminary result is As = 0.82±0.10(stat.)±0.07(syst.). Presented at the International Euroconference on Quantum Chromodynamics (QCD 98), 2-8 July 1998, Montpellier, France ∗Work supported by Department of Energy contracts: DE-FG0291ER40676 (BU), DE-FG0391ER40618 (UCSB), DE-FG0392ER40689 (UCSC), DE-FG0393ER40788 (CSU), DE-FG0291ER40672 (Colorado), DE-FG0291ER40677 (Illinois), DE-AC0376SF00098 (LBL), DE-FG0292ER40715 (Massachusetts), DE-FC0294ER40818 (MIT), DE-FG0396ER40969 (Oregon), DE-AC0376SF00515 (SLAC), DE-FG0591ER40627 (Tennessee), DE-FG0295ER40896 (Wisconsin), DE-FG0292ER40704 (Yale); National Science Foundation grants: PHY-9113428 (UCSC), PHY-8921320 (Columbia), PHY-9204239 (Cincinnati), PHY-9510439 (Rutgers), PHY-8819316 (Vanderbilt), PHY-9203212 (Washington); The UK Particle Physics and Astronomy Research Council (Brunel, Oxford and RAL); The Istituto Nazionale di Fisica Nucleare of Italy (Bologna, Ferrara, Frascati, Pisa, Padova, Perugia); The Japan-US Cooperative Research Project on High Energy Physics (Nagoya, Tohoku); The Korea Research Foundation (Soongsil, 1997).