Search for decays of the Higgs boson into pair-produced pseudoscalar particles decaying into ${\tau }^{+}{\tau }^{-}{\tau }^{+}{\tau }^{-}$ using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

ATLAS Collaboration

A search for a pair of low-mass pseudoscalars $a$ that promptly decay into $\tau$-leptons is presented using 140 fb${}^{-1}$ of proton-proton collision data at $13$ TeV centre-of-mass e…