We study the electroweak standard model at finite temperature in presence of a bosonic chemical potential associated with the conserved electromagnetic current. To preserve the thermodynamic equilibrium of the system, the thermal medium is neutralized by the introduction of four background charges related to the four gauge bosons of this model. Using the mean-field approximation, in the high te...

Electroweak radiative corrections give rise to large negative, double-logarithmically enhanced corrections in the TeV region. These are partly compensated by real radiation and, moreover, affected by selecting isospin-noninvariant external states. We investigate the impact of real gauge boson radiation more quantitatively by considering different restricted final state configurations. We consid...

Since it explains how the weak gauge bosons acquire their mass, the Higgs mechanism is a key point of the electroweak theory. In the Standard Model (SM), the Higgs mechanism predicts the existence of a scalar massive particle, the Higgs boson, which has never been observed yet. Because the SM is hardly consistent with the hierarchy between the Planck scale and the electroweak scale, it is certa...

We study the observability for a Standard Model-like Higgs boson at an upgraded Tevatron via the modes pp̄ → gg → h → W W ∗ → lνjj and lν̄l̄ν. We find that with c. m. energy of 2 TeV and an integrated luminosity of 30 fb the signal may be observable for the mass range of 135 GeV <∼ mh <∼ 180 GeV at a 3 − 5σ statistical level. Taking into account the existing results in the literature, we expect th...

We consider a dilute homogeneous mixture of bosons and spin-polarized fermions at zero temperature. We first construct the formal scheme for carrying out systematic perturbation theory in terms of single particle Green’s functions. We especially focus on the description of the boson-fermion interaction. To do so we need to introduce a new relevant object, the renormalized boson-fermion T -matri...

Lüscher’s finite size mass shift formula in a periodic finite volume, involving forward scattering amplitudes in the infinite volume, is revisited for the two stable distinguishable particle system. The generalized mass shift formulae for the boson and fermion are derived in the boson-boson and fermion-boson systems, respectively. The nucleon mass shift formula is given in the nucleon-pion syst...

The weak boson fusion process for neutral Higgs boson production is investigated with particular attention to the accuracy with which the Higgs boson couplings to weak bosons can be determined in final states that contain a Higgs boson plus at least two jets at CERN Large Hadron Collider energies. We determine that an accuracy of δg/g ∼ 10% on the effective coupling g may be possible after the ...

A CP-even neutral Higgs boson with standard-model-like couplings may be the lightest scalar of a twoHiggs-doublet model. We study the decoupling limit of the most general CP-conserving two-Higgs-doublet model, where the mass of the lightest Higgs scalar is significantly smaller than the masses of the other Higgs bosons of the model. In this case, the properties of the lightest Higgs boson are n...

A Higgs boson with mass below 150 GeV has a total decay width of less than 20 MeV into accessible Standard Model states. This narrow width means that the usual branching fractions for such a light Higgs boson are highly susceptible to any new particles to which it has unsuppressed couplings. In particular, there are many reasonable and interesting theoretical ideas that naturally imply an invis...

It is unlikely that a high statistics study of r-lepton decays will be sensitive to the Higgs boson sector of electroweak physics. A Tau-Charm Factory is an ideal facility for the study of rare deca.ys of the rlepton. At a machine discussed in these Proceedings, one might expect to produce on the order of lo7 r’s per year. It is an interesting exercise to consider whether such a data sample is ...