Reconstruction of top quark pair dilepton decays in electron-positron collisions

摘要

A new algorithm is presented to perform the full kinematic reconstruction of top quark pair events produced at future electron-positron colliders in the case of dilepton decays of the W bosons to electrons or muons. The momentum components of the undetected neutrino and antineutrino in the event are reconstructed by employing several kinematic conditions comprising a nonlinear system of six equations. This system is solved numerically using two independent methods, and the selection of the best candidate real solution for each event is determined by a likelihood discriminant. Results are presented for several reconstructed kinematic properties of the W~± bosons, top (and antitop) quarks using generator level information produced at leading order.