Top-quark polarization and asymmetries at the LHC in the effective description of squark interactions

Abstract

A detailed study of top-quark polarizations and tt charge asymmetries, induced by topsquark-pair production at the LHC and the subsequent decayst → tχ 0 1 , is performed within the effective description of squark interactions, which includes the effective Yukawa couplings and another logarithmic term encoding the supersymmetry breaking. This effective approach is more suitable for its introduction into Monte-Carlo simulations and we make use of its implementation in MadGraph in order to investigate the possibilities of the charge asymmetry A C , measured at the LHC and consistent with SM expectations, to discriminate among different SUSY scenarios and analyze the implications of these scenarios in the top polarizations and related observables. * arian@unizar.es † ernesto.arganda@unizar.es ‡ siannah@unizar.es

Polarization of top and chargino from stop decay in natural SUSY

“…It should be noted that the top quark produced from stop decay is polarized due to the parity-violating interactions of stop. The polarization effects can be measured from the kinematics of the decay products [20][21][22][23][24][25][26][27][28], which can be utilized to reveal the features of stop and other non-SM couplings of the third generation quarks [29][30][31][32][33][34][35]. For example, the top polarization was used to probe the mixing in the stop sector at future lepton colliders [36].…”