Pseudoscalar portal dark matter and new signatures of vector-like fermions

摘要: Fermionic dark matter interacting with the Standard Model sector through a pseudoscalar portal could evade direct detection constraints while preserving WIMP miracle. Here, we study LHC on production in simplified models either dominantly coupled to b quarks or $${ {\tau}}$$ leptons and explore their implications for GeV excesses gamma ray observations. We also investigate new vector-like fermions that realize simplfied of matter. Furthermore, these yield decay channels signatures fermions, instance, bbb; b$${ {\tau}}$$, resonances. Some have already been strongly constrained by existing searches parameter space fitting excess is further restricted. Conversely, pure {\tau}}$$-rich final state only weakly so far due small electroweak rate.