CMS collaboration (2304 authors)Nayak, ArunaBargassa, PedrameDa Cruz E Silva, Crist�v�o Beir�oDi Francesco, AgostinoFaccioli, PietroGalinhas, BrunoGallinaro, MicheleHollar, JonathanLeonardo, NunoIglesias, Lara LloretSeixas, JoaoStrong, GilesToldaiev, OleksiiVadruccio, DanieleVarela, JoaoVischia, PietroDavid Tinoco Mendes, AndreSilva, PedroMusella, Pasquale2019-02-052019-02-052018-09-10http://dx.doi.org/10.1007/JHEP09(2018)046http://hdl.handle.net/10400.26/27667A search for dark matter particles is performed by looking for events with large transverse momentum imbalance and a recoiling Higgs boson decaying to either a pair of photons or a pair of τ leptons. The search is based on proton-proton collision data at a center-of-mass energy of 13 TeV collected at the CERN LHC in 2016 and corresponding to an integrated luminosity of 35.9 fb$^{−1}$. No significant excess over the expected standard model background is observed. Upper limits at 95% confidence level are presented for the product of the production cross section and branching fraction in the context of two benchmark simplified models. For the Z$^{′}$-two-Higgs-doublet model (where Z$^{′}$ is a new massive boson mediator) with an intermediate heavy pseudoscalar particle of mass m$_{A}$ = 300 GeV and m$_{DM}$ = 100 GeV, the Z$^{′}$ masses from 550 GeV to 1265 GeV are excluded. For a baryonic Z$^{′}$ model, with m$_{DM}$ = 1 GeV, Z$^{′}$ masses up to 615 GeV are excluded. Results are also presented for the spin-independent cross section for the dark matter-nucleon interaction as a function of the mass of the dark matter particle. This is the first search for dark matter particles produced in association with a Higgs boson decaying to two τ leptons.engjournal article2019-02-05