The 28 gev dimuon excess in lepton specific thdm

Abstract

We explore the Higgs mass spectrum in a class of Two Higgs Doublet Models (THDMs) in which a scalar SU (2)(L) doublet interacts only with quarks, while the second one interacts only with leptons. The spectrum includes two CP-even Higgs bosons, either of which can account for the SM-like Higgs boson, and the spectra involving light Higgs bosons receive strong impacts from the LEP results and the current collider analyses. We find that a consistent spectrum can involve a CP-odd Higgs boson as light as about 10 GeV, while the lightest CP-even Higgs boson cannot be lighter than about 55 GeV when m(A) similar to 28 GeV. These analyses can rather bound the low tan beta region which can also accommodate an observed excess in dimuon events at m(mu mu) similar to 28 GeV. A lepton-specific class of THDMs (LS-THDM) can predict such an excess through A -> mu mu decays, while the solutions can be constrained by the A -> tau tau mode. After constraining the solutions with the consistent ranges of sigma(pp -> bbA -> bb tau tau), a largest excess at about 1.5 sigma at 8 TeV center of mass (COM) energy and 2 sigma at 13 TeV COM is observed for tan beta similar to 12 and m(A) similar to 28 GeV in the sigma(pp -> bbA -> bb mu mu) events.