Summary

The concept of these scenarios is the following. The signature in question is the decay of a heavy Higgs to a SM Higgs and another Higgs :

The benchmark is provided as a line for different decays of and . The line denotes the maximum cross section times branching ratio that the NMSSM scans gave. A summary of the benchmark lines visually is given here: plot of lines

The lines in root format are available here: HXSG_NMSSM_recommendations_00.root

Short description

The lines correspond to the maximum cross-section times branching ratio allowed in the (real) NMSSM after experimental constraints from Higgs boson measurements, searches for supersymmetry, B-meson physics and dark matter detection as implemented in the used codes NMSSMTools 5.5.0 [1] and NMSSMCALC [2].

[1] U.~Ellwanger, J.~F.~Gunion and C.~Hugonie, JHEP {\bf 0502} (2005) 066, [hep-ph/0406215], and U.~Ellwanger and C.~Hugonie, Comput.\ Phys.\ Commun.\ {\bf 175} (2006) 290 [hep-ph/0508022]. (https://www.lupm.univ-montp2.fr/users/nmssm/codes.html)

[2] J.~Baglio, R.~Gröber, M.~Mühlleitner, D.~T.~Nhung, H.~Rzehak, M.~Spira, J.~Streicher and K.~Walz, Comput.\ Phys.\ Commun.\ {\bf 185} (2014) no.12, 3372, [arXiv:1312.4788 [hep-ph]]. (https://www.itp.kit.edu/~maggie/NMSSMCALC/)

Long description

The masses of the NMSSM-specific mostly singlet-like scalar and pseudoscalar bosons H_S and A_S (which are NOT degenerate) are not constrained by present searches for BSM Higgs bosons if their couplings to SM particles are very small, which is the case in most regions of the NMSSM parameter space. Then their direct production cross sections are very small as well.

However, they can be produced in decays of mostly MSSM-like scalar and pseudoscalar bosons H_MSSM and A_MSSM which exist in the NMSSM as well. The branching fractions for H_MSSM->H_S+H_125 and A_MSSM->A_S+H_125 can be large, even dominant, even for pure singlet-like H_S and A_S. In this case the constraints from searches for H_MSSM and A_MSSM in other final states like tautau would be considerably alleviated.

This motivates the search for resonant pair production of H_S+H_125 and A_S+H_125. A difficulty is that both processes involve two unknown masses H_MSSM/H_S and A_MSSM/A_S, respectively, but the final states are not very different from those in H_125 pair production.

Benchmark points for these processes including production cross sections times branching fractions (Xsect*BR) have been presented previously in 1408.1120, 1707.08522, 1901.02332 and on the twiki page "NMSSMBenchmarkPoints" for various choices of the involved masses and final states. Promising final states are H_S+H_125 -> bb+bb, H_S+H_125 -> tautau+tautau, and A_S+H_125 -> gamgam(from A_S) + bb(from H_125).

In the figures below we show maximally possible Xsect*BRs in the NMSSM parameter space consistent with a) constraints on couplings of H_125 and searches for BSM Higgs bosons (from HiggsBounds/HiggsSignals) b) constraints from dark matter direct detection (asking for a relic density equal or below the WMAP bound) c) constraints from sparticle searches, B-physics and LEP.

These maximally possible Xsect*BRs have been obtained by the codes NMSSMTools_5.5.0 and NMSSMCALC. Due to the different implementation of radiative corrections the maximally possible Xsect*BRs differ somewhat by up to ~13% which we consider as a theoretical uncertainty.

It turns out that the maximally possible Xsect*BRs for H_S+H_125 -> tautau+tautau are always ~10% of the maximally possible Xsect*BRs for H_S+H_125 -> bb+bb. The maximally possible Xsect*BRs for A_S+H_125 -> gamgam+bb can be relatively large since the BR(A_S->gamgam) can be up to ~90%.

Of course, both sets of maximally possible Xsect*BRs decrease with the masses of H_MSSM and A_MSSM as shown in the figures. (The combination of the above constraints imply lower limits on the masses of H_MSSM and A_MSSM which are stronger than those from direct searches for H_MSSM and A_MSSM.) On the other hand the maximally possible Xsect*BRs depend little on the masses of H_S and A_S, so we concentrate on MH_S~100-110 GeV and MA_S~100-103 GeV, motivated by possible excesses in searches for BSM Higgses in this mass range. But we underline that searches should not be confined to the shown mass values. An additional info is that the widths of the heavy resonances vary from ~2 GeV up to ~14 GeV for masses up to 1 TeV.

-- RompotisNikolaos - 2020-03-16