Theoretical Model Proposes 'Boomerang Mechanism' to Explain Excess Radio Background
Physicists have proposed a theoretical mechanism involving dark neutrinos that could explain the excess radio background detected by the ARCADE 2 observatory. The model suggests that in the early universe, relic neutrinos converted into dark neutrinos through mixing, which later decay into dark photons and dark fermions. The proposal offers a testable framework for understanding anomalous cosmic radio emissions while avoiding constraints on neutrino magnetic moments.
A new theoretical paper published in Physical Review D proposes a 'boomerang mechanism' to account for excess radio background radiation detected by ARCADE 2. The model posits that during an early stage of the universe at temperatures between 0.1 keV and 1 MeV, a fraction of relic neutrinos underwent resonant conversion into dark neutrinos through mixing induced by pre-existing lepton asymmetry. These dark neutrinos would then decay much later into dark-standard photon states and dark fermions, with decay timescales exceeding the current age of the universe. The mechanism circumvents existing upper bounds on neutrino magnetic moments while establishing a testable lower bound on this quantity. This represents one theoretical approach among several being explored to resolve the ARCADE 2 anomaly.
What's missing
The paper does not discuss how this mechanism compares quantitatively to alternative explanations for the ARCADE 2 excess (such as contributions from unresolved point sources, galactic synchrotron emission, or other exotic physics), nor does it provide observational predictions that would definitively distinguish this model from competing theories.
What different sources said
- arXiv astro-phCenter
Boomerang mechanism explaining the excess radio background
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