Study of the heavy CP-even Higgs with mass 125 GeV in two-Higgs-doublet models at the LHC and ILC

Abstract:We determine the next-to-leading order renormalization group equations for the Two-Higgs-Doublet model with a softly broken Z 2 symmetry and CP conservation in the scalar potential. We use them to identify the parameter regions which are stable up to the Planck scale and find that in this case the quartic couplings of the Higgs potential cannot be larger than 1 in magnitude and that the absolute values of the S-matrix eigenvalues cannot exceed 2.5 at the electroweak symmetry breaking scale. Interpreting the 125 GeV resonance as the light CP -even Higgs eigenstate, we combine stability constraints, electroweak precision and flavour observables with the latest ATLAS and CMS data on Higgs signal strengths and heavy Higgs searches in global parameter fits to all four types of Z 2 symmetry. We quantify the maximal deviations from the alignment limit and find that in type II and Y the mass of the heavy CP -even (CP -odd) scalar cannot be smaller than 340 GeV (360 GeV). Also, we pinpoint the physical parameter regions compatible with a stable scalar potential up to the Planck scale. Motivated by the question how natural a Higgs mass of 125 GeV can be in the context of a Two-Higgs-Doublet model, we also address the hierarchy problem and find that the Two-Higgs-Doublet model does not offer a perturbative solution to it beyond 5 TeV.

Section: Jhep11(2015)052mentioning

confidence: 99%

Global fits of the two-loop renormalized Two-Higgs-Doublet model with soft Z 2 breaking

Chowdhury

Eberhardt

2015

“…The combined ATLAS and CMS data imply that the observed ∼ 125.5 GeV state is quite consistent with SM-like Higgs boson. Recent 2HDM efforts [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] have thus focused on the extent to which deviations from the SM are still possible and the implications for possibly observing such deviations and/or the other Higgs bosons in future LHC running. Of course, one must keep in mind that there is still an enhanced γγ signal in the ATLAS analysis whereas γγ rates are somewhat suppressed according to the CMS analysis and it is only the combined results that show no γγ enhancement.…”

Section: Fitting the 8 Tev Lhc Higgs Signal In The 2hdmmentioning

confidence: 99%

“…That the 2HDM can provide a consistent description of all LHC observed signal strengths for either the h or H identified as the observed ∼ 125. 5 GeV state (for the Type I or Type II version of the model) is well-known [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34]. For simplicity, in this paper we consider only the case of m h ∼ 125.5 GeV.…”

Section: Introductionmentioning

confidence: 99%

Extending two-Higgs-doublet models by a singlet scalar field — The case for dark matter

Drozd

Grza̧dkowski

Gunion

et al. 2014

Abstract:We extend the two-Higgs doublet models of Type I and Type II by adding a real gauge-singlet scalar S dark matter candidate (2HDMS models). We impose theoretical constraints deriving from perturbativity, stability, unitarity and correct electroweak symmetry breaking and require that the lightest CP-even Higgs, h, fit the LHC data for the ∼ 125.5 GeV state at the 68% C.L. after including existing constraints from LEP and B physics and LHC limits on the heavier Higgs bosons. We find that these models are easily consistent with the LUX and SuperCDMS limits on dark-matter-Nucleon scattering and the observed Ωh 2 for S masses above about 55 GeV. At lower m S , the situation is more delicate. For points with m S in the 6-25 GeV range corresponding to the CDMS II and CRESST-II positive signal ranges, the dark-matter-Nucleon cross sections predicted by the Type I and Type II models more or less automatically fall within the 95%-99% C.L. signal region boundaries. Were it not for the LUX and SuperCDMS limits, which exclude all (almost all) such points in the case of Type I (Type II), this would be a success for the 2HDMS models. In fact, in the case of Type II there are a few points with 5.5 GeV m S 6.2 GeV that survive the LUX and SuperCDMS limits and fall within the CDMS II 99% C.L. signal region. Possibilities for dark matter to be isospin-violating in this 2HDMS context are also examined.

“…So, the process pp → tthh opens a new avenue to measure di-Higgs physics at HL-LHC and a future 100 TeV pp-collider. On the other hand, given the limited precision of the LHC, an e + e − collider is crucial to scrutinize the detailed properties of the Higgs boson that might uncover the new physics beyond the SM [86][87][88][89][90][91][92][93][94][95][96]. In e + e − collision, the double Higgs strahlung e + e − → Zhh is considered as the main production process to measure the Higgs self-coupling.…”

Section: Jhep09(2015)008mentioning

confidence: 99%

Enhancing t t ¯ h h $$ t\overline{t}hh $$ production through CP-violating top-Higgs interaction at the LHC and future colliders

Liu

Zhang

Han

et al. 2015

The measurement of Higgs self-coupling is one of the most crucial physics goals at the future colliders. At the LHC, the di-Higgs production is a main way to measure the Higgs trilinear coupling. As a complementary to the di-Higgs production, tthh process may open a new avenue to measure di-Higgs physics at the LHC and a future 100 TeV pp collider or a high energy e + e − collider since the extra tt in the final states may efficiently suppress the backgrounds. However, such a kind of process is also controlled by the topHiggs coupling. In this work, we investigate the impact of CP-violating top-Higgs coupling on tthh production at the LHC, e + e − and a 100 TeV hadron collider under the current Higgs data. Within 2σ Higgs data allowed parameter region, we find that the cross section of tthh at the LHC-14 TeV, e + e − -1 TeV and VHE-LHC/SPPC-100 TeV can be enhanced up to 2.1 times the SM predictions. The future precise measurement of Higgs coupling will reveal the nature of top-Higgs interaction and improve the sensitivity of the determination of Higgs self-coupling through tthh production.