Measurements of Higgs boson production cross-sections in the H → τ + τ − decay channel in pp collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

Measurements of the production cross-sections of the Standard Model (SM) Higgs boson (H) decaying into a pair of τ-leptons are presented. The measurements use data collected with the ATLAS detector from pp collisions produced at the Large Hadron Collider at a centre-of-mass energy of $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 139 fb −1. Leptonic (τ → ℓν ℓ ν τ ) and hadronic (τ → hadrons ν τ ) decays of the τ-lepton are considered. All measurements account for the branching ratio of H → ττ and are performed with a requirement |y H | < 2.5, where y H is the true Higgs boson rapidity. The cross-section of the pp → H → ττ process is measured to be 2.94 ± $0.21{\left(\text{stat}\right)}_{-0.32}^{+0.37}$ (syst) pb, in agreement with the SM prediction of 3.17 ± 0.09 pb. Inclusive cross-sections are determined separately for the four dominant production modes: 2.65 ± $0.41{\left(\text{stat}\right)}_{-0.67}^{+0.91}$ (syst) pb for gluon-gluon fusion, 0.197 ± $0.028{\left(\text{stat}\right)}_{-0.026}^{+0.032}$ (syst) pb for vector-boson fusion, 0.115 ± $0.058{\left(\text{stat}\right)}_{-0.040}^{+0.042}$ (syst) pb for vector-boson associated production, and 0.033 ± $0.031{\left(\text{stat}\right)}_{-0.017}^{+0.022}$ (syst) pb for top-quark pair associated production. Measurements in exclusive regions of the phase space, using the simplified template cross-section framework, are also performed. All results are in agreement with the SM predictions.