Related papers: Residual New Physics Effects in $e^+e^-$ and $\gam…
Collisions of particles at the energy frontier can reveal new particles and forces via localized excesses. However, the initial observation may be consistent with a large variety of theoretical models, especially in sectors with new top…
We extend the Standard Model with the general effective Hamiltonian for the quark level transition $c \to s \ell \nu$ with a complete set of four fermion operators including right-handed neutrinos. The current experimental measurements in…
Measurements of top quark production at $e^+e^-$ colliders can provide a leap in precision in our knowledge of top quark properties and open a new window on physics beyond the Standard Model. In this contribution the top quark physics…
With the advent of the LHC, we will be able to probe New Physics (NP) up to energy scales almost one order of magnitude larger than it has been possible with present accelerator facilities. While direct detection of new particles will be…
We describe the anticipated experimental program of an e+e- linear collider in the energy range 500 GeV -- 1.5 TeV. We begin with a description of current collider designs and the expected experimental environment. We then discuss precision…
The ability of high energy $e^+e^-$ colliders to indirectly probe the existence of heavy new charged gauge bosons via their exchange in the reaction $e^+e^-\to \nu\bar\nu\gamma$ is investigated. It is shown that examination of the resulting…
Precision measurements of high energy top quarks at the LHC constitute a powerful probe of new physics. We study the effect of four fermion operators involving two tops and two light quarks on the high energy tail of the $t\bar t$ invariant…
We report on a study of the physics potential of linear $e^+e^-$ colliders. Although a linear collider (LC) would support a broad physics program, we focus on the contributions that could help elucidate the origin of electroweak symmetry…
We obtain mass limits on the extra neutral gauge boson which is predicted in a model with hidden gauge symmetry and dynamical breaking of the electroweak symmetry by a top quark condensate. For typical model assumptions, present LEP data…
We perform a preliminary study of the deviations from the Standard Model prediction for the cross section for the process $e \gamma \rightarrow \nu_e W \gamma$. We work in the context of a higgsless chiral lagrangian model that includes an…
Complementary to the conventional experimental studies on $N^*$ from $\pi N$ and $\gamma^{(*)}N$ reactions, the $e^+e^-$, $pp$ and $p\bar p$ collisions can give novel insights into these $N^*$ resonances. While the $e^+e^-$ collisions…
Recent experimental results of ${\cal R}(D^{(*)})$ deviate from the standard model (SM) by $3.1\sigma$, suggesting a new physics (NP) that affects the $b\to c \tau \bar\nu_\tau$ transition. Motivated by this, we investigate the possible NP…
Although direct detection of new particles will be the main focus of the LHC, indirect New Physics searches are expected to provide useful complementary information. In particular, precision measurements of rare processes occurring in…
We present a study of the sensitivity to models of new physics of proton collisions resulting in three electroweak bosons. As a benchmark, we analyze models in which an exotic scalar field $\phi$ is produced in association with a gauge…
Contrary to the general trend of looking for new physics at energies beyond the current reach of the Large Hadron Collider (LHC), this article proposes a strategy to look for light new physics via a meticulous study of well known and…
In the N=1 supersymmetric extension of the Standard Model, neutralinos associated in supermultiplets with the neutral electroweak gauge and Higgs bosons are, as well as gluinos, Majorana fermions. They can be paired with the Majorana…
An introduction to the physics of electroweak symmetry breaking is given. We discuss Higgs boson production in $e^+e^-$ and hadronic collisions and survey search techniques at present and future accelerators. Indirect limits on the Higgs…
The past ten years of physics with e+e- colliding experiments at LEP and SLAC have shown the success of these experiments on not only impressively proving the theoretical predictions of the Standard Model (SM), but also to help provide…
An attempt is made to present the effect of new physics in the exclusive decays of W boson at high energy colliders in the Randall-Sundrum (RS) model. By using Feynman diagram techniques we have evaluated the influence of the scalar…
We discuss the potentialities of the non-standard interaction study via the Higgs boson production at photon ($\ggam$ and $e\gamma$) colliders. We estimate the scale of New Physics phenomena beyond the standard model that can be seen in the…