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Saurabh Rindani

Publications and source records attributed to Saurabh Rindani.

4 recordsLinked to original sources

W boson polarization as a measure of gauge-Higgs anomalous couplings at the LHC

We show how the $W$ boson polarization in the process of associated $W^{\pm}H$ production at the Large Hadron Collider (LHC) can be used to constrain anomalous $WWH$ couplings. We first calculate the spin density matrix for the $W$ to linear order in the anomalous couplings, which are assumed to be small. We then evaluate angular asymmetries in the decay distributions of leptons produced in the decay of the $W$ and show how they can be used to measure the individual elements of the polarization tensor. We estimate the limits that can be placed on the anomalous $WWH$ couplings at a future run of the LHC.

hep-ph

Looking for bSM physics using top-quark polarization and decay-lepton kinematic asymmetries

We explore beyond Standard Model (bSM) physics signatures in the $l+jets$ channel of $t\overline{t}$ pair production process at the Tevatron and the LHC. We study the effects of bSM physics scenarios on the top quark polarization and on the kinematics of the decay leptons. To this end, we construct asymmetries using the lepton energy and angular distributions. Further, we find their correlations with the top polarization, net charge asymmetry and top forward backward asymmetry. We show that used together, these observables can help discriminate effectively between SM and different bSM scenarios which can lead to varying degrees of top polarization at the Tevatron as well as the LHC. We use two types of coloured mediator models to demonstrate the effectiveness of proposed observables, an $s$-channel axigluon and a $u$-channel diquark.

hep-ph

Trilinear Neutral Gauge Boson Couplings

We study the CP even trilinear neutral gauge boson vertices at one-loop in the context of the Standard Model and the Minimal Supersymmetric Standard Model, assuming two of the vector bosons are on-shell. We also study the changes in the form-factors when these two bosons are off-shell.

hep-ph

Top Quarks and $CP$ Violation in Polarized $e^+e^-$ Collisions

Electroweak dipole moments of the top quark are conjectured and their effect in polarized $e^+e^-$ collisions is examined for the expectation values of two different $CP$-odd observables. One of these observables probes the real part of the dipole moments whereas the other probes their imaginary part. It turns out that varying the polarization of the electron beam substantially enhances the resolving power of the experiment. PostScript version: preprints/mpi9454.ps from gluon.hep.physik.uni-muenchen.de

hep-ph