Details

Autor(en) / Beteiligte

• Nieves, José F.
• Sahu, Sarira

Titel

Neutrino damping in a fermion and scalar background

Ist Teil von

• Physical review. D, 2019-05, Vol.99 (9), p.095013, Article 095013

Ort / Verlag

College Park: American Physical Society

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We consider the propagation of a neutrino in a background composed of a scalar particle and a fermion using a simple model for the coupling of the form λf¯RνLϕ. In the presence of these interactions there can be damping terms in the neutrino effective potential and index of refraction. We calculate the imaginary part of the neutrino self-energy in this case, from which the damping terms are determined. The results are useful in the context of dark matter-neutrino interaction models in which the scalar and/or fermion constitute the dark matter. The corresponding formulas for models in which the scalar particle couples to two neutrinos via a coupling of the form λ(ννϕ)ν¯RcνLϕ are then obtained as a special case, which can be important also in the context of neutrino collective oscillations in a supernova and in the early Universe hot plasma before neutrino decoupling. A particular feature of our results is that the damping term in a νϕ background is independent of the antineutrino-neutrino asymmetry in the background. Therefore, the relative importance of the damping term may be more significant if the neutrino-antineutrino asymmetry in the background is small, because the leading Z-exchange and ϕ-exchange contributions to the effective potential, which are proportional to the neutrino-antineutrino asymmetry, are suppressed in that case, while the damping term is not.