QCD corrections to Higgs boson pair production and decay to the $b\bar{b}τ^+τ^-$ final state

Abstract: We present a comprehensive investigation of next-to-leading order (NLO) quantum chromodynamics (QCD) corrections to Higgs boson pair production and subsequent decay into $b\bar{b}\tau^+ \tau^-$. We adopt the narrow width approximation to separate the production and decay contributions, and employ the dipole subtraction method to address infrared divergences inherent in perturbative QCD corrections. After applying a set of typical experimental cuts, we show that NLO QCD corrections to the decay process induce a significant reduction of the fiducial cross section and reshape important kinematic distributions at the 13.6 TeV LHC, such as the invariant mass of the Higgs boson pair and the transverse momentum of the leading $b$-jet. We also investigate the dependence of the kinematic distributions on the Higgs self-coupling and provide the signal acceptance as a function of the Higgs self-coupling modifier with full QCD corrections.