Particle astrophysics

  • Article
    | Open Access

    The IceCube Neutrino Observatory has been recording a flux of high-energy cosmic neutrinos since 2013. Here, the authors investigate the possibility of increasing its sensitivity by implementing wavelength shifting optics within IceCube’s drill holes.

    • Imre Bartos
    • , Zsuzsa Marka
    •  & Szabolcs Marka
  • Article
    | Open Access

    The composition of dark matter in the universe remains a mystery, with one hypothetical form being topological defects. Here the authors determine a stronger constraint on the coupling of this dark matter to atomic clocks on board global positioning satellites through the analysis of 16 years of archival data.

    • Benjamin M. Roberts
    • , Geoffrey Blewitt
    •  & Andrei Derevianko
  • Article
    | Open Access

    The Van Allen radiation belts are two zones of energetic particles encircling the Earth, but how electrons are accelerated to relativistic energies remains unclear. Here, the authors analyse a radiation belt event and provide evidence in favour of the ULF wave-driven radial diffusion mechanism.

    • Zhenpeng Su
    • , Hui Zhu
    •  & J. R. Wygant
  • Article |

    Gamma-ray bursts are short-lived luminous explosions at cosmological distances caused by jets from the deaths of massive stars. Bustamante et al. study neutrino, gamma-ray and cosmic-ray production by internal shocks, and find that multi-messenger observations are crucial to understand the evolving outflows.

    • Mauricio Bustamante
    • , Philipp Baerwald
    •  & Walter Winter
  • Article |

    TheFermispacecraft recently observed gamma-ray emission from supernova remnant W44, however, the mechanism is unclear. Here, the authors show that strong ion-neutral collisions in the remnant surrounding lead to the steepening of the energy spectrum of accelerated particles by one power.

    • M. A. Malkov
    • , P. H. Diamond
    •  & R. Z. Sagdeev
  • Article |

    The origin of the highest energy cosmic rays is still unknown. Here, Chakraborti and colleagues show that a recently discovered sub-population of type Ibc supernovae with mildly relativistic outflows can satisfy all required characteristics for an ultra-high-energy cosmic ray source.

    • S. Chakraborti
    • , A. Ray
    •  & P. Chandra