Detection of heavy charged Higgs bosons in e+ e- -> t anti-b H- production at future linear colliders

Moretti, S. (2004) Detection of heavy charged Higgs bosons in e+ e- -> t anti-b H- production at future linear colliders. The European Physical Journal C, 34, 157-163. (doi:10.1140/epjc/s2004-01668-9).

Record type: Article

Abstract

Heavy charged Higgs bosons (H^±) of a Type II 2-Higgs doublet model (2HDM) can be detected at future electron–positron Linear Colliders (LCs) even when their mass is larger than half the collider energy. The single Higgs mode e⁺e^- → t¯bH^-+ c.c. → 4b+jj+ℓ+p^miss_T (where j represents a jet and with ℓ = e,µ) contributes to extend the discovery reach of H^± states into the mass region M_H± √s/2, where the well studied pair production channel e+e^- → H^-H⁺ is no longer available. With a technique that allows one to reconstruct the neutrino four-momentum in the decay t → bW⁺ →bℓ⁺ν, one can suppress the initially overwhelming main irreducible background due to e⁺e^- → t¯tb¯b (via a gluon splitting into b¯b pairs) to a negligible level. However, for currently foreseen luminosities, one can establish a statistically significant H^± signal only over a rather limited mass region, of 20 GeV or so, beyond M_H± ~ √s/2, for very large or very small values of tan β and provided high b-tagging efficiency can be achieved.