English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We propose a minimal seesaw extension to simultaneously account for realisticneutrino mass and mixing, the baryon asymmetry of the Universe via leptogenesisand a viable dark matter relic density, in which two right-handed neutrinos arecoupled to a dark Dirac fermion and complex scalar field, both charged under aglobal $U(1)_D$ symmetry. As a concrete example, we consider the LittlestSeesaw model which describes neutrino mass and mixing and accounts forleptogenesis, thereby fixing the neutrino Yukawa couplings and right-handedneutrino masses. By considering the freeze-in production mechanism of darkmatter, we explore the parameter space of right-handed neutrino portalcouplings and dark particle masses which give the correct dark matter relicabundance, focussing on the case of a superheavy Dirac fermion dark matterparticle, with a mass around $10^{10}$ GeV. Such a FIMPzilla can provide asuccessful explanation of the dark matter relic abundance, with its productionreliant on neutrino Yukawa couplings over much of the parameter space,depending on the assumed dark particle masses, and the reheat temperature.

Minimal Seesaw extension for Neutrino Mass and Mixing, Leptogenesis and Dark Matter: FIMPzillas through the Right-Handed Neutrino Portal