The main goal of the Fermilab Muon g-2 experiment is to determine the muon anomalous magnetic moment ($a_\mu$) to a 140 parts per billion (ppb) uncertainty, to compare it with the Standard Model prediction. The value of $a_\mu$ is determined by measuring two quantities: the anomalous spin precession frequency of positive muons circulating in a storage ring and the magnetic field experienced by...
The electromagnetic coupling constant, $\alpha$, is one of the fundamental parameters of the Standard Model (SM). Its value at the Z boson mass, $\alpha(M_Z)$, is of particular interest as it enters EW precision tests. When running $\alpha$ from low energies up to the Z mass, five orders of magnitude in precision are lost. This makes it one of the least well determined parameters of the SM at...
We explore the CP-violating (CPV) effects of heavy New Physics in the flavour-changing quark dipole transitions, within the framework of Standard Model Effective Field Theory (SMEFT). We connect the operators defined at the heavy scale $\Lambda$ with the low energy observable via the Renormalisation Group (RG) evolution of the appropriate Wilson coefficients. We investigate RG-induced...
Inspired by the various LHCb results of lepton flavour violation on $b\to s$ transition we will study the lepton flavour violating $\Sigma_b\to\Sigma l_1l_2$ decays in terms of transversity amplitudes in non-universal Z' model. These LFV processes are extremely suppressed in the Standard Model (SM) because the expected levels at the SM lie far below current experimental sensitivities. In...
In the Standard Model of particle physics, lepton flavour and lepton number are conserved quantities, although there is no fundamental symmetry associated with their conservation and lepton flavour violation has been already confirmed by the observation of neutrino oscillations.
Many lepton flavour violating (LFV) and lepton number violating (LNV) processes can be searched for in B meson...
Rare baryonic decays induced by flavour changing neutral current (FCNC) have been of immense interest in recent years because of their sensitivities towards new physics (NP) beyond the standard model (SM). The exploration had been triggered with the observation of $\Lambda_b\to\Lambda\mu^+\mu^−$ transition at the Fermilab [1] and the LHCb [2]. Theoretically these decays are also studied at...
The High-Intensity Muon Beams (HIMB) project aims to increase the rate of the intensity muon beamlines at Paul Scherrer Institute (PSI) by two orders of magnitude up to 10^10 µ+/s, with a significant impact on low-energy, high-precision muon-based experiments. This is done by improving the surface muon yield with a new target geometry and by increasing capture and transmission with...
The Standard Model (SM) of particle physics successfully predicts many fundamental properties and interactions, but it is still incomplete. Models like baryogenesis or leptogenesis for the matter-antimatter asymmetry lead to an additional CP violation beyond the SM. In this context, electric dipole moments (EDMs), which violate time-reversal and parity symmetry, and by virtue of the CPT...
The angular correlation distribution of electron-positron pairs from Internal Pair Conversion emitted by excited 8Be and 4He nucleus was measured by ATOMKI. Over the expected monotonically decreasing trend was measured a significant excess which can be interpreted as the production of a hypothetical particle (X17) whose mass is around 17 MeV.
The MEG-II experiment at the Paul Scherrer...
The study of non-perturbative properties characterizing Quantum Chromo-Dynamics (QCD) is of relevant theoretical and phenomenological interest. Indeed, the $\theta$-dependence of QCD is related to open issues such as the strong-$CP$ violation or to the Peccei-Quinn axion physical properties.
The lattice approach is a natural first-principle tool to investigate the non-perturbative properties...
