Wolfenstein potentials for neutrinos induced by ultra-light mediators

Understand

New physics can emerge at low energy scales, involving very light and very weakly interacting new particles.

• These particles can mediate interactions between neutrinos and usual matter and contribute to the Wolfenstein potential relevant for neutrino oscillations.
• We compute the Wolfenstein potential in the presence of ultra-light scalar and vector mediators and study the dependence of the potential on the mediator mass $m_A$, taking the finite size of matter distribution (Earth, Sun, supernovae) into consideration.
• For ultra-light mediators with $m_{A}^{-1}$ comparable to the size of the medium ($R$), the usual $m_{A}^{-2}$ dependence of the potential is modified.