Angular distributions in $t\bar{t}H(H\to b\bar{b})$ reconstructed events at the LHC

Abstract

The associated production of a Higgs boson and a top-quark pair, $t\bar{t}H$, in proton-proton collisions is addressed in this paper for a center of mass energy of 13TeV at the LHC. Dileptonic final states of $t\bar{t}H$ events with two oppositely charged leptons and four jets from the decays $t\to b{W}^{+}\to b{\ell }^{+}{\nu }_{\ell }$, $\bar{t}\to \bar{b}{W}^{-}\to \bar{b}{\ell }^{-}{\bar{\nu }}_{\ell }$ and $h\to b\bar{b}$, are used. Signal events, generated with MadGraph5_aMC@NLO, are fully reconstructed by applying a kinematic fit. New angular distributions of the decay products as well as angular asymmetries are explored in order to improve discrimination of $t\bar{t}H$ signal events over the dominant irreducible background contribution, $t\bar{t}b\bar{b}$. Even after the full kinematic fit reconstruction of the events, the proposed angular distributions and asymmetries are still quite different in the $t\bar{t}H$ signal and the dominant background ($t\bar{t}b\bar{b}$).

Comments: 12 pages, 14 figures