Neutrino bound states and bound systems

Understand

Yukawa interactions of neutrinos with a new light scalar boson $\phi$ can lead to formation of stable bound states and bound systems of many neutrinos ($\nu$-clusters).

• For allowed values of the coupling $y$ and the scalar mass $m_\phi$, the bound state of two neutrinos would have the size larger than $10^{12}$ cm.
• Bound states with sub-cm sizes are possible for keV scale sterile neutrinos with coupling $y > 10^{-4}$.
• For $\nu$-clusters we study in detail the properties of final stable configurations.