Particle physics today faces the challenge of explaining the mystery of dark matter, the origin
of matter over anti-matter in the Universe, the origin of the neutrino masses, the apparent …

With the establishment and maturation of the experimental programs searching for new
physics with sizeable couplings at the LHC, there is an increasing interest in the broader …

The existence of nonzero neutrino masses points to the likely existence of multiple Standard
Model neutral fermions. When such states are heavy enough that they cannot be produced …

A bstract We make a comparative study of the neutrinoless double beta decay constraints on
heavy sterile neutrinos versus other direct and indirect constraints from both lepton number …

We review and revise phenomenology of the GeV-scale heavy neutral leptons (HNLs). We
extend the previous analyses by including more channels of HNLs production and decay …

Neutrinoless double beta decay (0 ν β β) is a crucial test for lepton number violation.
Observation of this process would have fundamental implications for neutrino physics …

The Deep Underground Neutrino Experiment (DUNE) is an international, world-class
experiment aimed at exploring fundamental questions about the universe that are at the …

We for the first time map the range of active-sterile neutrino mixing angles in which
leptogenesis is possible in the type I seesaw model with three heavy neutrinos with …

The electron-positron stage of the Future Circular Collider, FCC-ee, is a frontier factory for
Higgs, top, electroweak, and flavour physics. It is designed to operate in a 100 km circular …

This report, as part of the 2021 Snowmass Process, summarizes the current status of collider
physics at the Energy Frontier, the broad and exciting future prospects identified for the …