Related papers: Tree Level Unitarity Bounds for the Minimal B-L Mo…
In the Minimal Supersymmetric Standard Model (MSSM) the existence of an upper bound on the mass of the $CP=+1$ lightest Higgs boson, equal to $m_Z$ at tree--level and $\simlt 120\ GeV$ after the inclusion of radiative corrections, has…
We use the results of Maher {\em et al.\/} (preceding paper) to construct the matrix of $j=0$ partial-wave two-body and $2\rightarrow3$ scattering amplitudes for the scattering of longitudinally polarized gauge bosons $W_L^\pm$, $Z_L$ and…
In hep-ph/0011311 the one Higgs doublet standard model was obtained by an orbifold projection of a 5D supersymmetric theory in an essentially unique way, resulting in a prediction for the Higgs mass m_H = 127 \pm 8 GeV and for the…
Gauging $B-L$ symmetry provides a simple realization of the seesaw mechanism in a naturally anomaly free extension to the MSSM gauge group, $SU(3)_c\times SU(2)_L\times U(1)_Y \times U(1)_{B-L}$. However, as we discuss in here, it turns out…
We show that the expected size of the maximum agreement subtree of two $n$-leaf trees, uniformly random among all trees with the shape, is $\Theta(\sqrt{n})$. To derive the lower bound, we prove a global structural result on a decomposition…
We study the theoretical and phenomenological constraints imposed on the scalar sector of the gauged two Higgs doublet model proposed recently as a variant of the popular inert Higgs doublet model of dark matter. The requirements of…
We have investigated some phenomenological aspects of an $SU(2)\times U(1)$ scenario where scalars belonging to arbitrary representations of $SU(2)$ are involved in electroweak symmetry breaking. The resulting interaction terms are derived.…
We investigate the phenomenology of the Standard Model extended by a real gauge-singlet scalar field, focusing on exotic Higgs decay channels. For a light scalar mass in the range \(0 < m_{\phi} < 40\) GeV, the Higgs boson can decay to both…
We consider the Two Higgs Doublet Model (2HDM) of type III which leads to Flavour Changing Neutral Currents (FCNC) at tree level. In the framework of this model we can use an appropriate form of the Yukawa Lagrangian that makes the type II…
We calculate the complete matrix of two-body scattering amplitudes for the scattering of longitudinally polarized gauge bosons $W_L^\pm$, $Z_L$ and Higgs bosons to two loops in the high-energy, heavy-Higgs limit $\sqrt{s}\gg M_H\gg M_W$.…
One-loop contributions to the Higgs potential at finite temperatures are discussed in the supersymmetric standard model with four Higgs doublet chiral superfields as well as a pair of charged singlet chiral superfields. The mass of the…
We study pion-nucleon scattering at tree level with a chiral lagrangian of pions, nucleons, and $\Delta$-isobars using a K-matrix unitarization procedure. Evaluating the scattering amplitude to order $Q^2$, where $Q$ is a generic small…
We present exact tree-order amplitudes for $H^* \to n~H$, for final states containing one or two particles with non-zero three-momentum, for various interaction potentials. We show that there are potentials leading to tree amplitudes that…
I show that the gravitational scattering amplitudes of a spin-5/2 field with mass $m\ll M_{Pl}$ violate tree-level unitarity at energies $\sqrt{s}\approx\sqrt{mM_{Pl}}$ if the coupling to gravity is minimal. Unitarity up to energies…
The maximally helicity violating (MHV) tree level scattering amplitudes involving three, four or five gravitons are worked out in Unimodular Gravity. They are found to coincide with the corresponding amplitudes in General Relativity. This a…
The integration of heavy scalar fields is discussed in a class of BSM models, containing more that one representation for scalars and with mixing. The interplay between integrating out heavy scalars and the Standard Model decoupling limit…
We present lower bounds on the Higgs boson mass in the Standard Model with three and four fermion generations SM(3,4), as well as upper bounds on the lightest Higgs boson mass in the minimal supersymmetric extension of the SM with three and…
We search for the neutral Higgs sector of the next-to-minimal supersymmetric standard model at LEP 2. At the tree level any experimental constraints on $\tan \beta$ cannot be set by the Higgs search at LEP 2 with $\sqrt{s}$ = 175 GeV,…
Using the LHC and Tevatron data, we set upper and lower limits on the total width of the Higgs-like boson. The upper limit is based on the well-motivated assumption that the Higgs coupling to a W or Z pair is not much larger than in the…
We study the Two-Higgs-Doublet Model predicted in the minimal theory for quark-lepton unification that can describe physics at the low scale. We discuss the relations among the different decay widths of the new Higgs bosons and study their…