Invariant-mass threshold resummation for the production of four top quarks at the LHC

A bstract Using invariant-mass threshold resummation, we compute the invariant-mass distribution and the total cross section for $$ t\overline{t}t\overline{t} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>t</mml:mi> <mml:mover> <mml:mi>t</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> <mml:mi>t</mml:mi> <mml:mover> <mml:mi>t</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> production at the LHC with centre-of-mass energy of 13 . 6 TeV at NLL ′ accuracy. This accuracy includes next-to-leading logarithmic contributions together with relative 𝒪( α s ) non-logarithmic terms present in the threshold limit. We match the NLL ′ results to NLO in QCD and to complete NLO with electroweak corrections. We find that the inclusion of NLL ′ soft-gluon corrections significantly reduces the size of the theoretical uncertainties and greatly improves the convergence of the predictions when considering various choices of renormalisation and factorisation scales.