The role of dineutrino modes in the search for new physics

TL;DR

Dineutrino modes are promising for new physics searches, enabling novel tests of Standard Model symmetries and lepton universality through combined analyses across charm, beauty, and kaon decays.

Contribution

This paper reviews the potential of dineutrino modes in testing SM symmetries and explores their applications in charm, beauty, and kaon decays for new physics insights.

Findings

New bounds on tau-lepton couplings with electrons and muons.

Novel tests of lepton universality and flavor conservation.

Improved constraints on flavor-changing processes.

Abstract

Dineutrino modes offer promising searches for new physics. The potential aspects of these modes are reviewed in detail. Performing a proper combination of them, novel tests of the SM symmetries are derived. Different phenomenological applications are worked out, including charm, beauty and kaons, which result in novel tests of lepton universality and charged lepton flavour conservation with flavour-summed dineutrino observables, in addition to improved bounds on $\tau\,\ell$ couplings with $\ell=e,\mu,\tau$.