Probing the Higgs portal at the LHC through resonant di-Higgs production

Abstract

We investigate resonant di-Higgs production as a means of probing extended scalar sectors that include a 125 GeV Standard Model-like Higgs boson. For concreteness, we consider a gauge singlet Higgs portal scenario leading to two mixed doublet-singlet states, h 1;2 . For m h 2 > 2m h 1 , the resonant di-Higgs production process pp → h 2 → h 1 h 1 will lead to final states associated with the decaying pair of Standard Model-like Higgs scalars. We focus on h 2 production via gluon fusion and on the bbτ þ τ − final state. We find that discovery of the h 2 at the LHC may be achieved with ≲100 fb −1 of integrated luminosity for benchmark parameter choices relevant to cosmology. Our analysis directly maps onto the decoupling limit of the next-to-minimal supersymmetric Standard Model and more generically onto extensions of the Standard Model Higgs sector in which a heavy scalar produced through gluon-fusion decays to a pair of Standard Model-like Higgs bosons.

Non-resonant collider signatures of a singlet-driven electroweak phase transition

“…• As mentioned in the Introduction, resonant di-Higgs production at the LHC [11,14,29,38] and a future 100 TeV hadron collider [12,13,15,39] would be expected to probe portions of the parameter space with m 2 > 2m 1 . Ref.…”

“…A particularly powerful probe will be measurements of the Zh production cross-section at lepton colliders, which can deviate from its SM predicted value due to mixing effects and the wavefunction renormalization of the Higgs-like scalar h [18,19]. A combination of these approaches, in addition to gravitational wave experiments such as LISA [20], show promise in probing the EWPT in singlet models [10][11][12][13][14][15][16][17][20][21][22][23][24][25][26].…”

“…refs. [11][12][13][14][15] and references therein). This is an attractive channel because of its potentially large cross-section, especially at a 100 TeV collider.…”

ATLAS on-Z excess via gluino-Higgsino-singlino decay chains in the NMSSM

“…singlet-like Higgs and SM processes [64][65][66][67][68]. This resonance signal, however, would become narrower than results in the literature due to the small singlet-doublet mixing in our benchmark points.…”

Impact of top-Higgs couplings on Di-Higgs production at future colliders

“…Besides, a large deviation in the self-coupling may be a direct evidence for strong first-order electroweak phase transition in the early universe [58,59]. At the LHC, the di-Higgs production is the only way to measure the Higgs self-coupling and is dominated by the gluon-gluon fusion mechanism, which has JHEP01(2015)008 been widely studied in recent years (see examples in SM after 125 GeV Higgs boson [60][61][62][63][64]; see examples in MSSM and NMSSM after 125 GeV Higgs boson, [65][66][67][68][69]; see examples in 2HDM after 125 GeV Higgs boson, [70][71][72][73]; see examples in other models after 125 GeV Higgs boson, [74][75][76][77][78][79][80][81][82][83][84][85]). Among various decay channels, although the 4b final state has the largest fraction, the rare process hh → bbγγ is expected to have the most promising sensitivity due to the low QCD backgrounds at the LHC [86][87][88][89][90][91][92][93].…”