相关论文: Perturbative unitarity bounds for fermions composi…
Motivated by the recent hints of lepton flavour non-universality in $B$-meson semi-leptonic decays, we study the constraints of perturbative unitarity on the new physics interpretation of the anomalies in $b \to c \ell \bar \nu$ and $b \to…
We consider the theory of four-fermion interactions with N-component fermions in de Sitter space. It is found that the effective potential for a composite operator in the theory is calculable in the leading order of the 1/N expansion. The…
We derive rigorous bounds on the average momentum occupation numbers $\langle n_{\mathbf{k}\sigma}\rangle$ in the Hubbard and Kondo models in the ground state and at non-zero temperature ($T>0$) in the grand canonical ensemble. For the…
An observation of any lepton number violating process will undoubtedly point towards the existence of new physics and indirectly to the clear Majorana nature of the exchanged fermion. In this work, we explore the potential of a minimal…
We provide a general framework for handling the effects of a unitary disturbance on the estimation of the amplitude $\lambda$ associated to a unitary dynamics. By computing an analytical and general expression for the quantum Fisher…
Physics from beyond the Standard Model can induce four fermion operators involving a quark, an anti-quark, a lepton and an anti-lepton. The coefficients of these operators can be constrained by various observations. We update the bounds…
We consider lepton-antilepton annihilation into a fermion-antifermion pair at variable c.m. energy. We propose for this process a simple parametrization of the virtual effects of the most general model of new physics of…
We consider all the dimension 6 operators as well as some simple extensions of the standard model that give new contributions to neutrino interactions with matter. Such interactions are usually parametrized by $\epsilon_{\alpha \beta}$,…
Effective Field Theory (EFT) is a general framework to parametrize the low-energy approximation to a UV model that is widely used in model-independent searches for new physics. The use of EFTs at the LHC can suffer from a 'validity' issue,…
Grand Unified Theories (GUTs) are attractive candidates for more fundamental elementary particle theories. They can not only unify the Standard Model (SM) interactions but also different types of SM fermions, in particular quarks and…
This doctoral dissertation presents several works on nonstandard properties of neutrinos exploiting the synergies between effective field theory and models. The phenomena are first analysed by means of effective operators, which allow to…
The detectability of the fermion-potentials appearing in a unified model of fermions is discussed from the viewpoint of an effective field theory. Although the fermion-potentials are effectively represented as terms similar to the…
Motivated by recent development of the concept of the disorder operator and its relation with entanglement entropy in bosonic systems, here we show the disorder operator successfully probes many aspects of quantum entanglement in fermionic…
This work presents new constraints on the existence and the binding energy of a possible $\Lambda$-$\Lambda$ bound state, the H-dibaryon, derived from $\Lambda$-$\Lambda$ femtoscopic measurements by the ALICE collaboration. The results are…
In this paper, we investigate the contributions of anomalous quartic gauge couplings (aQGCs) to $Z\gamma jj$ production at the Large Hadron Collider (LHC) in the context of Standard Model effective theory (SMEFT). When energy scale is…
We investigate the ground-state properties of trapped fermion systems described by the Hubbard model with an external confining potential. We discuss the universal behaviors of systems in different regimes: from few particles, i.e. in…
We study the sensitivity to physics beyond the standard model of precise top-quark pair production measurements at future lepton colliders. A global effective-field-theory approach is employed, including all dimension-six operators of the…
A low energy non-unitary leptonic mixing matrix is a generic feature of many extensions of the Standard Model. In such a case, the task of future precision neutrino oscillation experiments is more ambitious than measuring the three mixing…
A density functional theory is proposed for strongly interacting fermions with arbitrary large negative scattering length. The functional has only two parameters that are directly fixed to reproduce the universal properties of unitary gas:…
Non-standard scenarios described by effective contactlike interactions can be revealed only by searching for deviations of the measured observables from the Standard Model (SM) predictions. If deviations were indeed observed within the…