Higgs mass from D-terms: a litmus test

Abstract

We explore supersymmetric theories in which the Higgs mass is boosted by the non-decoupling D-terms of an extended U (1)X gauge symmetry, defined here to be a general linear combination of hypercharge, baryon number, and lepton number. Crucially, the gauge coupling, gX , is bounded from below to accommodate the Higgs mass, while the quarks and leptons are required by gauge invariance to carry non-zero charge under U (1)X . This induces an irreducible rate, σBR, for pp → X → relevant to existing and future resonance searches, and gives rise to higher dimension operators that are stringently constrained by precision electroweak measurements. Combined, these bounds define a maximally allowed region in the space of observables, (σBR, mX ), outside of which is excluded by naturalness and experimental limits. If natural supersymmetry utilizes non-decoupling D-terms, then the associated X boson can only be observed within this window, providing a model independent 'litmus test' for this broad class of scenarios at the LHC. Comparing limits, we find that current LHC results only exclude regions in parameter space which were already disfavored by precision electroweak data.

Supersymmetric D-term Twin Higgs

“…Such models were considered in the context of non-twinned SUSY in refs. [32][33][34][35][36][37][38][39][40][41]. The non-decoupling D-term potential can be written as…”

“…For large values of g X the most stringent constraint comes from searches for off-shell production of the X boson in dimuon final states at LEP which gives a lower bound of m X 4350 GeV ×g X [36]. 7 Since the limit is stronger for larger g X the fine-tuning is not necessarily smaller for larger g X .…”

“…(A.5) and (A.7) are consistent with the model-independent discussion in ref. [36]. Let us comment on the possible sources of the fine-tuning in addition to ∆ f due to the threshold correction.…”

Impact of an extra gauge interaction on naturalness of supersymmetry

“…We point out that this problem is relaxed in extensions of the MSSM such that the Higgs is charged under extra gauge symmetry, which have been extensively discussed becuase they alllow for the 125 GeV Higgs mass with relatively small stop masses [15][16][17][18][19][20][21][22]. The running of the top Yukawa coupling is given by…”

“…This has motivated a great amount of work on various extensions of the MSSM in which new positive contributions to the Higgs mass are present which allow for the 125 GeV Higgs mass without heavy stops. The most notable examples of such models are Next-To-Minimal Supersymmetric Standard Model (NMSSM) [6][7][8][9][10][11][12][13][14] and models with non-decoupling D-terms of some new gauge interactions under which the Higgs is charged [15][16][17][18][19][20][21][22]. However, even if the observed Higgs mass is obtained with light stops the fine-tuning is still present due to constraints on supersymmetric particles, especially on stops and gluino, from direct LHC searches [23,24].…”