Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userTriple and Quartic Interactions of Higgs Bosons in the General Two-Higgs-Doublet Model
158
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
In the case of minimal supersymmetric extension of the Standard Model (MSSM), when the pseudoscalar Higgs boson mass is less than the supersymmetry energy scale, the effective theory at the electroweak scale is a two-Higgs-doublet model. We diagonalize the mass matrix of the general two-Higgs-doublet model, expressing Higgs boson self-couplings in terms of two mixing angles and four Higgs boson masses, and derive in a compact form the complete set of Feynman rules, including quartic couplings in the Higgs sector, for the case of CP-violating potential. Some processes of double and triple Higgs boson production at a high-energy linear collider are calculated in the case of mixing angles and scalar boson masses satisfying the MSSM constraints.
rate research
Read More
We apply the unitarity bounds and the bounded-from-below (BFB) bounds to the most general scalar potential of the two-Higgs-doublet model (2HDM). We do this in the Higgs basis, i.e. in the basis for the scalar doublets where only one doublet has vacuum expectation value. In this way we obtain bounds on the scalar masses and couplings that are valid for all 2HDMs. We compare those bounds to the analogous bounds that we have obtained for other simple extensions of the Standard Model (SM), namely the 2HDM extended by one scalar singlet and the extension of the SM through two scalar singlets.
Motivated by an anomaly in $R(D^{(*)})={rm BR}(bar{B}rightarrow D^{(*)} tau^-bar{ u})/{rm BR}(bar{B}rightarrow D^{(*)} l^-bar{ u})$ reported by BaBar, Belle and LHCb, we study $R(D^{(*)})$ in a general two Higgs doublet model (2HDM). Although it has been suggested that it is difficult for the 2HDM to explain the current world average for $R(D^{(*)})$, it would be important to clarify how large deviations from the standard model predictions for $R(D^{(*)})$ are possible in the 2HDM. We investigate possible corrections to $R(D^{(*)})$ in the 2HDM by taking into account various flavor physics constraints (such as $B_c^-rightarrow tau^- bar{ u}$, $brightarrow sgamma$, $brightarrow s l^+l^-$, $Delta m_{B_{d,s}}$, $B_srightarrow mu^+mu^-$ and $tau^+tau^-$, and $B^-rightarrow tau^- bar{ u}$), and find that it would be possible (impossible) to accommodate the 1$sigma$ region suggested by the Belles result when we adopt a constraint ${rm BR}(B_c^-rightarrow tau^- bar{ u})le30~%$ (${rm BR}(B_c^-rightarrow tau^- bar{ u})le10~%$). We also study productions and decays of heavy neutral and charged Higgs bosons at the Large Hadron Collider (LHC) experiment and discuss the constraints and implications at the LHC. We show that in addition to well-studied production modes $bgrightarrow tH^-$ and $ggrightarrow H/A$, exotic productions of heavy Higgs bosons such as $cgrightarrow bH^+,t+H/A$ and $cbar{b}rightarrow H^+$ would be significantly large, and the search for their exotic decay modes such as $H/Arightarrow tbar{c}+cbar{t},~mu^pmtau^mp$ and $H^+rightarrow cbar{b}$ as well as $H/Arightarrow tau^+tau^-$ and $H^+rightarrow tau^+ u$ would be important to probe the interesting parameter regions for $R(D^{(*)})$.
We present a study of triple Higgs boson (3H) production at the International Linear Collider (ILC) within the general Two-Higgs-Doublet Model (2HDM). We compute the production cross-sections at the leading-order for the 3H final states and find values up to sigma ~ 0.1 pb. This result represents a large enhancement with respect to the corresponding MSSM cross-sections, which stay typically at the level of sigma ~ 10^(-6) pb or less. Furthermore, since the 3H cross-sections in the general 2HDM can be of the order of the double Higgs production cross-sections, such 3H processes could be a competitive (if not the dominant) mechanism for Higgs boson production at the ILC. In practice, these 3H events could be identified through the tagging of 6 heavy-quark jet final states and, in this case, they would provide strong evidence of an extended Higgs boson sector -- likely of non-supersymmetric nature.
In this paper, we study the CP violating processes in a general two-Higgs-doublet model (2HDM) with tree-level flavor changing neutral currents. In this model, sizable Yukawa couplings involving top and charm quarks are still allowed by the collider and flavor experiments, while the other couplings are strongly constrained experimentally. The sizable couplings, in general, have imaginary parts and could largely contribute to the CP violating observables concerned with the $B$ and $K$ mesons. In particular, the contribution may be so large that it affects the direct CP violating $K$ meson decay, where the discrepancy between the experimental result and the Standard Model prediction is reported. We discuss how well the anomaly is resolved in the 2HDM, based on study of the other flavor observables. We also propose the way to test our 2HDM at the LHC.
We calculate the next-to-leading order (NLO) electroweak (EW) corrections to decay rates of charged Higgs bosons for various decay modes in the four types of two Higgs doublet models (THDMs) with the softly broken discrete Z_2 symmetry. Decay branching ratios of charged Higgs bosons are evaluated including NLO EW corrections, as well as QCD corrections up to next-to-next-to-leading order (NNLO). We comprehensively study impacts of the NLO EW corrections to the branching ratios in nearly alignment scenarios where the couplings constants of the Higgs boson with the mass of 125 GeV are close to those predicted in the standard model. Furthermore, in the nearly alignment scenario, we discuss whether or not the four types of THDMs can be distinguished via the decays of charged Higgs bosons. We find that characteristic predictions of charged Higgs branching ratios can be obtained for all types of the THDMs, by which each type of the THDMs are separated, and information on the internal parameters of the THDMs can be extracted from the magnitudes of the various decay branching ratios.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
