Prospects for observing the η ₜ → W⁺W⁻ decay at the HL-LHC

Motivated by the recent observation of the pseudoscalar toponium η ₜ η t at the LHC and by the ongoing interest in its properties, we phenomenologically investigate the η ₜ η t → → W⁺W⁻ W + W - process, one of the characteristic decays of toponium η ₜ η t . The branching ratio for the η ₜ η t → → W⁺W⁻ W + W - decay is estimated with two scenarios of the decay constant f_η ₜ f η t . It is found that tens of dilepton events from the cascade decays, η ₜ η t → → W⁺W⁻ W + W - → → ⁻ν ̄ ^ +ν _ ℓ - ν ¯ ℓ ℓ ′ + ν ℓ ′ with <jats:alterna