Related papers: Elimination of Threshold Singularities in the Rela…
We reconsider observables for discovering a heavy Higgs boson (with m_h > 2m_W) via its di-leptonic decays h -> WW -> l nu l nu. We show that observables generalizing the transverse mass that take into account the fact that both of the…
The Next-to-Minimal Supersymmetric Standard Model (NMSSM) offers a rich framework embedding physics beyond the Standard Model as well as consistent interpretations of the results about the Higgs signal detected at the LHC. We investigate…
The effect of threshold singularities induced by unstable particles on two-loop observables is investigated and it is shown how to cure them working in the complex-mass scheme. The impact on radiative corrections around thresholds is…
Renormalization of two-loop divergent corrections to the vacuum expectation values (v_1, v_2) of the two Higgs doublets in the minimal supersymmetric standard model, and their ratio $\tan\beta=v_2/v_1$, is discussed for general R_{\xi}…
We show that it is possible to distinguish between different off-shell completions of supergravity at the on-shell level. We focus on the comparison of the ``new minimal'' formulation of off-shell four-dimensional N=1 supergravity with the…
In Quantum Field Theory models with spontaneously broken gauge invariance, renormalizability limits to four the degree of the Higgs potential, whose minima determine the vacuum state at tree-level. In many models, this bound has the…
This paper examines the Higgs particle self-coupling and its implications for electroweak symmetry breaking in the Standard Model. We review the current experimental constraints on the Higgs trilinear coupling and discuss the challenges in…
We analyse the stability lower bounds on the Standard Model Higgs mass by carefully controlling the scale independence of the effective potential. We include resummed leading and next-to-leading-log corrections, and physical pole masses for…
We investigate the phenomenological consequences of a strict gauge-invariant formulation of the Higgs particle. This requires a description of the observable scalar particle in terms of a bound state structure. Although this seems to be at…
The possibility of a heavy supersymmetric spectrum at the Minimal Supersymmetric Standard Model is considered and the decoupling from the low energy electroweak scale is analyzed in detail. The formal proof of decoupling of supersymmetric…
The radiative decay width of a heavy Higgs boson $H \rightarrow W^+W^-\gamma$ for a {\it hard} photon is calculated in the Standard Model and its extension with anomalous $\gamma WW$ couplings. Its dependence on the Higgs mass, the two…
We perform a renormalisation group analysis of the next-to-minimal supersymmetric standard model (NMSSM) based on the following constraints: two-loop gauge coupling unification at a variable scale $M_X$, running the gauge couplings through…
Based on the observables $\MW$, $\Gamma_l$, $\bar\sw^2(\MZ^2)$, we evaluate the parameters $\Delta x, \Delta y$ and $\varepsilon$ at one-loop level within an electroweak massive vector-boson theory, which does not employ the Higgs…
In a general supersymmetric standard model there is an upper bound $m_h$ on the tree level mass of the $CP=+1$ lightest Higgs boson which depends on the electroweak scale, $\tan \beta$ and the gauge and Yukawa couplings of the theory. When…
The Higgs boson (H) decay width is determined from the ratio of off- and on-shell production of H $\to$ WW $\to$ e$\nu\mu\nu$ using proton-proton collision data corresponding to an integrated luminosity of 138 fb$^{-1}$ collected at…
As part of the search for new physics beyond the Standard Model, we chose the determination of the Higgs boson decay width as one of the least experimentally determined values. The decay widths into the four fermions of the lightest and…
It is usually believed that there are no perturbative anomalies in supersymmetric gauge theories beyond the well-known chiral anomaly. In this paper we revisit this issue, because previously given arguments are incomplete. Specifically, we…
We study the gauge invariance of physical observables in holographic theories under the local diffeomorphism. We find that gauge invariance is intimately related to the holographic renormalisation: the local counter terms defined in the…
The absence of any signal of supersymmetry (SUSY) at the LHC has raised the SUSY particle mass scale compared to $Z$ boson mass $M_Z$. We investigate the naturalness of the electroweak symmetry breaking after considering radiative symmetry…
We calculate a full set of one-loop corrections to the Higgs boson coupling constants as well as the electroweak parameters. We compute the decay rate of the standard model (SM)-like Higgs boson ($h$) into diphoton. Renormalized Higgs…