Neutrino, Photon Interaction in Unparticle Physics

TL;DR

This paper explores how unparticle physics influences ultra-high-energy cosmic ray production through neutrino annihilation, affecting cross-sections and decoupling temperatures, with potential implications for cosmic ray fluxes.

Contribution

It introduces the role of unparticle exchange in neutrino annihilation processes and estimates their impact on cosmic ray phenomena and neutrino-photon decoupling temperatures.

Findings

Unparticles can account for UHE cosmic ray fluxes.

Unparticles lower neutrino-photon decoupling temperature.

Enhanced neutrino annihilation cross-sections due to unparticles.

Abstract

We investigate the impact of unparticle physics on the annihilation of relic neutrinos with the neutrinos identified as primary source of ultra high energy (UHE) cosmic ray events, producing a cascade of photons and charged particles. We compute the contribution of the unparticle exchange to the cross-sections $\nu \bar\nu\to\gamma \gamma$ and $\nu \bar\nu\to f \bar f$ scattering. We estimate the neutrino photon decoupling temperature from the reaction rate of $\nu \bar\nu\to\gamma \gamma$. We find that inclusion of unparticles can in fact account for the flux of UHE cosmic rays and can also result in the lowering of neutrino - photon decoupling temperature below the QCD phase transition for unparticle physics parameters in a certain range. We calculate the mean free path of these high energy neutrinos annihilating themselves with the relic neutrinos to produce vector and tensor unparticles.