Extremely High Energy Neutrinos from Cosmic Strings

TL;DR

This paper predicts that cosmic string cusps can emit highly boosted moduli particles that decay into neutrinos with energies exceeding 10^{21} eV, potentially observable by future detectors.

Contribution

It introduces a novel mechanism for producing ultra-high-energy neutrinos from cosmic string cusps via moduli decay, extending previous models of cosmic ray origins.

Findings

Neutrinos with energies above 10^{21} eV can be produced from cosmic string cusps.

Predicted neutrino fluxes are within detection capabilities of upcoming observatories.

The model links superstring theory predictions to observable high-energy astrophysical phenomena.

Abstract

Superstring theory and other supersymmetric theories predict the existence of relatively light, weakly interacting scalar particles, called moduli, with a universal form of coupling to matter. Such particles can be emitted from cusps of cosmic strings, where extremely large Lorentz factors are achieved momentarily. Highly boosted modulus bursts emanating from cusps subsequently decay into gluons, they generate parton cascades which in turn produce large numbers of pions and then neutrinos. Due to very large Lorentz factors, extremely high energy neutrinos, up to the Planck scale and above, are produced. For some model parameters, the predicted flux of neutrinos with energies $\gtrsim 10^{21}$ eV is observable by JEM-EUSO and by the future large radio detectors LOFAR and SKA.