Eur Phys J C (2004) 33: s674-s676
https://doi.org/10.1140/epjcd/s2004-03-1616-4

PS07 Tests of the Standard Model

Top quark mass and properties at DØ

Physikalisches Institut der Universität Bonn, Nussallee 12, 53115 Bonn, Germany

Received: 14 October 2003
Accepted: 14 January 2004
Published online: 3 February 2004

Abstract

DØ has developed an optimized method to extract information on top quark properties. An Extended–Maximum–Likelihood method is used, where the event probabilities are obtained by convoluting the differential cross section with the resolution and acceptance of the detector. This method is used to remeasure the top quark mass in the lepton + jets sample collected by the DØ experiment during Run 1 of the Fermilab Tevatron. A new preliminary measurement of the top quark mass of M _t =180.1±3.6(stat)±4.0(sys) GeV is obtained, corresponding to a significant reduction in uncertainty on M _t . The method used can also be applied to other properties of the top quark, such as the polarization of the W’s in top decays.