QED corrections to the thermal neutrino interaction rate

Abstract

Motivated by precision computations of neutrino decoupling at MeV temperatures, we show how QED corrections to the thermal neutrino interaction rate can be related to the electron-positron spectral function as well as an effective $\bar{\nu }\nu \gamma$ vertex. The spectral function is needed both in a timelike and in a spacelike domain, and for both of its physical polarization states (transverse and longitudinal with respect to spatial momentum). Incorporating an NLO evaluation of this spectral function, an estimate of the $\bar{\nu }\nu \gamma$ vertex, and HTL resummation of scatterings mediated by soft Bose-enhanced $t$-channel photons, we compute the interaction rate as a function of the neutrino momentum and flavour. Effects on the $-(\mathrm{0...2})\%$ level are found, noticeably smaller than a previous estimate of a related quantity.

27 pages. v2: references and clarifications added

References in corpus (3)

• A precision calculation of relic neutrino decoupling
• Two-loop thermal spectral functions with general kinematics
• Efficient numerical integration of thermal interaction rates

Cited by in corpus (5)

• Constraints on primordial lepton asymmetries with full neutrino transport
• Lepton Flavor Asymmetries: from the early Universe to BBN
• Dynamics of metastable Standard Model particles from long-lived particle decays in the MeV primordial plasma
• Fast and Flexible Neutrino Decoupling Part I: The Standard Model
• Towards a precision calculation of $N_{\mathrm{eff}}$ in the Standard Model IV: Estimating the impact of positronium formation