Top-philic heavy resonances in four-top final states and their EFT interpretation

Abstract

With an expected rate of about one event per 100,000 top-quark pairs, four top-quark final states very rarely arise at the LHC. Though scarce, they offer a unique window onto topquark compositeness, self-interactions and more generically, onto any top-philic new physics. By employing simplified models featuring heavy resonances, we study the range of validity of effective theory interpretations of current four top-quark analyses at the LHC and establish their future reach at the HL-LHC. We find that for the class of models under consideration, the effective field theory interpretations are not applicable. We therefore present the most up-to-date limits obtained from public CMS and ATLAS analyses using simplified models. Finally, we put forward a novel recasting strategy for the experimental results based on the production of top quarks with large transverse momentum.

$t\bar{t}t\bar{t}$ signatures through the lens of color-octet scalars

“…On the other hand, as we discussed in Section 3.2, our reimplementation of ATLAS-CONF-2020-002 is less sensitive than the official multi-bin analysis, so the true limits from that search may rule out some more high-branching fraction parameter space. It is also worth noting that this limit is fairly close to that imposed by a previous CMS measurement [62,105,106] of σ(pp → t tt t) with a lower cross section and lower significance than the most recent ATLAS results. Finally, we observe that there is a point around m O or m o ≈ 800 GeV where ATLAS-CONF-2020-002 becomes more sensitive to our signals than the four-top analysis.…”

Probing top-philic new physics via four-top-quark production *

“…Finally, we evaluate a special case of a broad vector resonance proposed in Ref. [33]. The resonance decays mainly into a pair of top or bottom quarks, and the Lagrangian reads…”

Four top final states with NLO accuracy in perturbative QCD: 4 lepton channel

“…Moreover, in various new physics scenarios, the small SM cross section for the production of four top-quarks can be significantly enhanced. These BSM scenarios include among others models with a composite right-handed top quark [13][14][15][16], heavy Kaluza-Klein gluons and quarks from extra dimensions [17], scalar gluons occurring in supersymmetric models and produced in pairs [18,19], singly produced top-philic resonances [20,21] or a heavy scalar or pseudoscalar boson from extended electroweak symmetry breaking sectors produced in association with a top-quark pair [22][23][24][25]. In addition, the pp → t tt t process provides a direct way to constrain the SM Effective Field Theory Wilson coefficients sensitive to the quartic couplings between top-quarks [26][27][28].…”