Interference effects for the top quark decays t→ b+W⁺/H⁺(→τ⁺ν_τ)

2019/04/30 by S. Mohammad Moosavi Nejad, S. Abbaspour, R. Farashahian
Physics and Astronomy · #hep-ph

paper · pdf · doi:10.1103/physrevd.99.095012

published as Phys. Rev. D 99, 095012 (2019) · 10 pages, 10 figures, 51 References. Accepted by Physical Review D. arXiv admin note: text overlap with arXiv:1806.02546; text overlap with arXiv:1411.4652, arXiv:0911.3027 by other authors

arxiv created 2019/05/10 · arxiv updated 2019/05/22

Abstract

Applying the narrow-width approximation (NWA), we first review the NLO QCD predictions for the total decay rate of top quark considering two unstable intermediate particles: the W⁺-boson in the standard model (SM) of particle physics and the charged Higgs boson H⁺ in the generic type-I and II two-Higgs-doublet models, i.e. t→ b+W⁺/H⁺(→ τ⁺ν_τ). We then estimate the errors arised from this approximation at leading-order perturbation theory. Finally, we shall investigate the interference effects in the factorization of production and decay parts of intermediate particles. We will show that for nearly mass-degenerate states (m_H⁺≈ m_W⁺), the correction due to the interference effect is considerable.

Citations

• Indirect search for light charged Higgs bosons through the dominant semileptonic decays of top quark t→ b(→ B/D+X)+H⁺(→ τ⁺ν_τ)
• Interference effects in BSM processes with a generalised narrow-width approximation
• Radiatively corrected lepton energy distributions in top quark decays t → bW⁺ → b(ℓ⁺ ν_ℓ) and t → bH⁺ → b (τ⁺ ν_τ) and single charged prong energy distributions from subsequent τ⁺ decays