Search for additional neutral MSSM Higgs bosons in the τ τ final state in proton-proton collisions at $$ \sqrt{s}=13 $$ TeV

Abstract

A search is presented for additional neutral Higgs bosons in the ττ final state in proton-proton collisions at the LHC. The search is performed in the context of the minimal supersymmetric extension of the standard model (MSSM), using the data collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb −1 . To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes production of the Higgs boson in association with b quarks. No significant deviation above the expected background is observed. Model-independent limits at 95% confidence level (CL) are set on the product of the branching fraction for the decay into τ leptons and the cross section for the production via gluon fusion or in association with b quarks. These limits range from 18 pb at 90 GeV to 3.5 fb at 3.2 TeV for gluon fusion and from 15 pb (at 90 GeV) to 2.5 fb (at 3.2 TeV) for production in association with b quarks, assuming a narrow width resonance. In the m mod+ h scenario these limits translate into a 95% CL exclusion of tan β > 6 for neutral Higgs boson masses below 250 GeV, where tan β is the ratio of the vacuum expectation values of the neutral components of the two Higgs doublets. The 95% CL exclusion contour reaches 1.6 TeV for tan β = 60.

Heavy Higgs as a portal to the supersymmetric electroweak sector

“…The dashed curve in the left panel indicates the contour along which these two production cross sections (direct and via heavy Higgs decays) are equal. All regions of parameter space presented in these panels are consistent with current LHC bounds from A/H → τ τ [1,2] as well as pp →…”

“…Right Panel: Analogous plot for Br(A → staus), with parameter choices the same as for the neutralino plot, except mτ L = mτ R = m A /2 − 50 GeV, A τ = 1 TeV, and µ = 500 GeV, which are similar to the light stau scenario in [59] except for the modified values of A τ , mτ L , mτ R , and M 2 . In both panels, the shaded regions represent the parameter space excluded by currents LHC searches for A/H → τ τ [1,2], whereas all non-shaded regions are consistent with all current LHC bounds from various searches. these electroweak states, suggesting that these final states could provide observable channels at colliders.…”

“…For the sleptons, Higgsinos, and binos, the reach is relatively weak (searches and current limits are discussed in Section 2) due to their small direct pair-production cross sections. For the heavy Higgs bosons, the coverage is incomplete due to a lack of clean signatures at the LHCthere exist strong limits at large tan β 10 due to the presence of the A/H → τ τ decay channel [1,2], but the reach at low tan β 8 is relatively weak despite higher production cross sections since the dominant decay channel is tt, which is a very challenging signal due to its interference with the SM tt background [3] (see [4][5][6][7] for more recent studies).…”

Muon g − 2 vs LHC Run 2 in supersymmetric models

“…Although it can evaluate the relevant contributions to a SUSY µ at the two-loop level [51,52], we do not include them and use the one-loop result so that a SUSY µ is independent of the #5 Note that the heavy Higgs bosons are already strongly constrained by pp → H/A → τ τ searches when tan β is sizable. For instance, for tan β = 40, the ATLAS and CMS collaborations set a bound of MA 1.5 TeV by √ s = 13 TeV and dtL = 36 fb −1 [46,47]. In such a case, the heavy Higgs bosons are well decoupled in the neutral CP-even Higgs sector, and we have checked that branching ratios of the electroweakinos, which are relevant parameters in our analysis, are stable against the choice of the masses.…”

Collider constraints on lepton flavor violation in the 2HDM

“…The heavy scalars have been extensively searched for at the LHC. In particular CMS has been searching for the s-channel production of the heavy Higgs decaying into a tau-pair [20] and W -pair [21]. The former analysis covers the mass region m H > 90 GeV while the latter covers m H > 200 GeV.…”