Benchmarking LHC searches for light 2HDM+$\mathbf{a}$ pseudoscalars

Abstract

Using two suitable benchmark scenarios that satisfy the experimental constraints on the total decay width of the $125\mathrm{GeV}$ Higgs boson, we determine the bounds on light CP-odd spin-0 states in the 2HDM+$a$ model that arise from existing LHC searches. Our work represents the first thorough study that considers the parameter space with $m_a\lesssim 100\mathrm{GeV}$ and should prove useful for 2HDM+$a$ interpretations of future ATLAS, CMS and LHCb searches for pseudoscalars with masses below the electroweak scale.

Comments: 18 pages, 2 figures; v2: matches version accepted for publication in SciPost