2014ApJ...782...70K

We explore the generation and possibility for the detection of heavy-meson synchrotron emission due to the acceleration of ultra-relativistic protons (and possibly nuclei) in the presence of strong magnetic fields (H ≳ 10¹⁵ G) in transient astrophysical environments such as magnetar flares. We show that, in addition to the well-known pion synchrotron emission, heavy vector mesons like ρ, D_S, J/Ψ, and Υ could be generated. For high enough energies and magnetic field strengths, such heavy vector mesons can be formed with high intensity (∼10³ times the photon intensity) through strong couplings to the ultra-relativistic nucleons. We examine in particular the synchrotron emission and subsequent cooling and decay of the heavy ρ⁰ and Υ(1S) mesons, e.g., via p ⟶ p' + Υ(1S), Υ(1S) ⟶ τ⁺ + τ^–, τ^– ⟶ µ^– _µ + ν_τ and + e^– + _e + ν_τ. We evaluate the spectra of escaping ν_e, ν_µ, and ν_τ due to the decay of short-lived τ mesons. We deduce the possible event rate in a terrestrial TeV neutrino detector. We estimate that neutrinos produced from the heavy vector-meson synchrotron radiation from a strong magnetar soft gamma repeater burst will only be detectable with the current generation of detectors if the source is very nearby (<30 pc). Nevertheless, if ever detected, the existence of heavy meson synchrotron emission might be identifiable by the unique signature of energetic tau neutrinos emanating from the source.