Download or read book First Evidence for WW and WZ Diboson Production with Semi-leptonic Decays at a Hadron Collider written by and published by . This book was released on 2009 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented is a measurement of the simultaneous production of a W{sup ±} boson in association with a second weak boson (W{sup ±} or Z°) in p{bar p} collisions at √s = 1.96 TeV. Events are consider with one electron or one muon, missing transverse energy, and at least two hadronic jets. The data were collected by the D0 detector in Run IIa of the Tevatron accelerator and correspond to 1.07 fb−1 of integrated luminosity for each of the two channels (WW/WZ → e[nu]q{bar q} and WW/WZ → [mu][nu]q{bar q}). The cross section for WW + WZ production is measured to be 20.2 ± 2.5(stat) {+-} 3.6(sys) {+-} 1.2(lum) pb with a Gaussian significance of 4.4 standard deviations above the background-only scenario. This measurement is consistent with the Standard Model prediction and represents the first direct evidence for WW and WZ production with semi-leptonic decays at a hadron collider.