Binary neutron star mergers as the source of the highest energy cosmic rays
Abstract
We propose that ultrahigh energy cosmic rays are produced in binary neutron star mergers. This scenario can account for the heretofore inexplicable narrow rigidity range of UHECRs, because the jets of BNS mergers are generated by a gravitationally-driven dynamo and thus are nearly identical due to the narrow range of BNS masses. Observed UHECRs with energies well beyond 100 EeV can be explained as -process nuclei, without invoking an exotic source class. Evidence for this mechanism, and its prediction of coincidences between neutrinos above 10 PeV and gravitational waves, are discussed.
Keywords
Cite
@article{arxiv.2405.12004,
title = {Binary neutron star mergers as the source of the highest energy cosmic rays},
author = {Glennys R. Farrar},
journal= {arXiv preprint arXiv:2405.12004},
year = {2025}
}
Comments
Accepted PRL; revised; new material: 1) Evidence for a narrow rigidity distribution (Sec 1, SM). 2) Promising new mechanism: acceleration in the turbulent magnetized outflow; role of synchrotron emission in that context. 3) (Sec. 2, SM) Consistency with fluence limits on EHE neutrinos accompanying GW170817; estimate that next-generation neutrino and GW detectors may see EHEnu-GW coincidences