Related papers: Probing anomalous ZZH and gammaZH interactions at …
We discuss the potentialities of the study of CP-odd interactions of the Higgs boson with photons via its production at gamma-gamma and e-gamma colliders. Our treatment of H-gamma-gamma and H-Z-gamma anomalous interactions includes a set of…
We argue that the search for dark vector boson through $e^+e^-\to Z_d\gamma$ can determine the Lorentz structure of $Z_dl^+l^-$ couplings with the detection of leptonic decays $Z_d\to l^+l^-$. We assume a general framework that the dark…
We study anomalous $W^-W^+Z/\gamma$ couplings due to dimension-$6$ operators in the production process $e^-e^+ \to W^-W^+$ followed by semi-leptonic decay using polarizations and spin-spin correlations of $W$ bosons. The construction of…
We study electron-electron contact-interaction searches in the process e^+e^-\to e^+e^- at a future e^+e^- Linear Collider with both beams longitudinally polarized. We evaluate the model-independent constraints on the coupling constants,…
We discuss the sensitivity to four-fermion contact interactions of the process of fermion-pair production at the e^+ - e^- Linear Collider (LC), with E_{CM}=0.5 TeV and longitudinally polarized electron beam. The analysis is based on…
We discuss contact-interaction searches in the processes e^+e^-\to \mu^+\mu^-, b\bar{b} and c\bar{c} at an e^+e^- Linear Collider with c.m. energy \sqrt{s}=0.5 TeV and with longitudinally polarized beams. The measurement of polarized cross…
We consider the possibility of fingerprinting the presence of heavy additional Z' bosons that arise naturally in extensions of the standard model such as E_6 models and left-right symmetric models, through their mixing with the standard…
Rare decay of the Higgs boson is a powerful tool to probe new physics beyond the standard model. The rare decays occur through quantum loops in which the standard model and new physics contributions might cancel each other out. We consider…
Polarised electron and positron beams are key ingredients to the physics programme of future linear colliders. Due to the chiral nature of weak interactions in the Standard Model - and possibly beyond - the knowledge of the…
We study electron-electron contact-interaction searches in the process e^+e^-\to e^+e^- at a future e^+e^- Linear Collider with both beams longitudinally polarized. We evaluate the model-independent constraints on the coupling constants,…
In this work we investigate the single- and the double- spin asymmetries at the collisions of polarized protons $pp \to (\gamma*, Z^0,Z')+X within the scope of QCD, electroweak interaction and superstring E_6 theory. The helicity amplitude…
A study of Z-boson pair production in e+e- annihilation at center-of-mass energies between 190 GeV and 209 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nn), quark and lepton pairs, (qql+l-, qqnn) and only hadrons…
In this talk, we present novel methods to investigate light-quark dipole interactions at colliders. Our approach includes: (1) measuring azimuthal asymmetries of a collinear dihadron in semi-inclusive deep inelastic lepton scattering off an…
Beam polarization at e+ e- linear colliders will be a powerful tool for high precision analyses. Often it is assumed that the full information from polarization effects is provided by polarization of the electron beam and no further…
We present an analysis of the sensitivity of the TESLA e+ e- collider to top flavour-changing neutral couplings to the Z boson and photon. We consider the cases without beam polarization, with only e- polarization and with e- and e+…
In the context of HERA with polarized lepton and proton beams, we explore the sensitivity of the collider to contact interactions. We emphasize that the measurement of longitudinal spin asymmetries in such a polarized context could give…
We analyze the potential of the CERN Large Hadron Collider (LHC) to study anomalous quartic vector-boson interactions Z Z gamma gamma, Z Z Z gamma, W+ W- gamma gamma, and W+ W- Z gamma through the weak boson fusion processes q q -> q q…
The constraints on the anomalous quartic $WW\gamma\gamma$ and $ZZ\gamma\gamma$ gauge boson couplings are investigated through the processes $e\gamma\to W^{-}\gamma\nu_{e}$ and $e\gamma\to Z\gamma e$. Considering the longitudinal and…
We study the potential of a future $e^+e^-$ collider for the search of anomalous gamma t t bar and Z t t bar couplings, assuming that CP-invariance holds. This is done in a model-independent way, considering that all six possible couplings…
We analyze the influence of anomalous gauge couplings in the reaction $e^- \: e^- \longrightarrow e^- \: W^- \: \nu_e$ at a 500 GeV linear collider. The limits imposed by this process on deviations from the standard model of electro-weak…