Related papers: Pseudo-observables in Higgs decays
The relation between physical observables measured at LHC and Tevatron and standard model Higgs pseudo-observables (production cross section and partial decay widths) is revised by extensively using the notion of the Higgs complex pole on…
We discuss how the leading electroweak Higgs production processes at the LHC, namely vector-boson fusion and Higgs+W/Z associated production, can be characterized in generic extensions of the Standard Model by a proper set of…
While the Higgs characterisation programme is well underway, direct signs for new physics beyond the Standard Model remain elusive. Performing a fit of fully differential Higgs production cross sections at the LHC to a subset of…
We analyze the bounds on the Higgs pseudo-observables following from electroweak constraints, under the assumption that the Higgs particle is the massive excitation of an $SU(2)_L$ doublet. Using such bounds, detailed predictions for $h\to…
We study the indirect effects of New Physics in the Higgs decay into four charged leptons, using an Effective Field Theory (EFT) approach to Higgs interactions. We evaluate the deviations induced by the EFT dimension-six operators in…
We show how leading radiative corrections can be implemented in the general description of $h\to 4\ell$ decays by means of Pseudo Observables (PO). With the inclusion of such corrections, the PO description of $h\to 4\ell$ decays can be…
We study the decays $h \to \ell \bar{\ell} \left(Z \to \ell' \bar{\ell'}\right)$ and $h\to\ell\bar{\nu}_\ell\nu_{\ell'}\bar{\ell'}$ within the SMEFT framework and including effects up to $\mathcal O(1/\Lambda^4)$, where $\Lambda$ is the new…
We discuss some consistency tests that must be passed for a successful explanation of a diphoton excess at larger mass scales, generated by a scalar or pseudoscalar state, possibly of a composite nature, decaying to two photons. Scalar…
Depending on whether electroweak physics beyond the Standard Model is based on a linear or on a non-linear implementation of the electroweak symmetry breaking, a linear or a chiral Effective Lagrangian is more appropriate. In this talk, the…
Precise measurements of SM particles properties at the LHC allows to look for heavy New Physics in the context of an Effective Field Theory (EFT). These searches, however, often rely on kinematic regions where the validity of the EFT may be…
The Higgs particle can have dominantly invisible decay in a large class of Majoron models as well as some SUSY models. The LEP signal and mass limit for a Higgs particle undergoing invisible decay are explored. They are found to be very…
The consecutive steps of H to tau tau cascade can be useful for the measurement of Higgs couplings and parity. The analysis methos of ATLAS and CMS Collaborations was to fit a one-dimensional distribution of the phi* angle, phi*, which is…
The Higgs and some of the Standard Model superpartners may have been copiously produced at LEP and the Tevatron without being detected. We study a novel scenario of this type in which the Higgs decays predominantly into a light hidden…
We discuss briefly the kappa framework, proposed originally as a test for the Higgs couplings of the Standard Model (SM). Further, we discuss a generalization of this idea in terms of effective field theory. We sketch how to add dimension 6…
We propose a new type of search for a pseudoscalar particle $\eta$ pair produced via an off-shell Higgs, $pp\to h^*\to \eta\eta$. The search is motivated by a composite Higgs model in which the $\eta$ is extremely narrow and decays almost…
We discuss effective field theories (EFTs) for the Higgs particle, which is not necessarily the Higgs of the Standard Model. We distinguish two different consistent expansions: EFTs that describe decoupling new-physics effects and EFTs that…
Among the possible decay modes of Higgs particles into supersymmetric states, neutralino and chargino decays play a prominent r\^ole. The experimental opportunities of observing such decay modes at LEP2 and at future e+e- linear colliders…
In a recent paper we showed that the electroweak chiral Lagrangian at leading order is equivalent to the conventional $\kappa$ formalism used by ATLAS and CMS to test Higgs anomalous couplings. Here we apply this fact to fit the latest…
Recent LEP searches for Higgs bosons in models other than the Minimal Standard Model and the Minimal Supersymetric Standard Model are reviewed. Limits are presented for Higgs bosons decaying into diphotons or invisible particles, and for…
We study the indirect effects of new physics on the phenomenology of the recently discovered "Higgs-like" particle. In a model independent framework these effects can be parametrized in terms of an effective Lagrangian at the electroweak…