Evidence for vacuum birefringence from the first optical-polarimetry measurement of the isolated neutron star RX J1856.5−3754

  title={Evidence for vacuum birefringence from the first optical-polarimetry measurement of the isolated neutron star RX J1856.5−3754},
  author={Roberto P. Mignani and Vincenzo Testa and Denis Gonz{\'a}lez Caniulef and Roberto Taverna and Roberto Turolla and Silvia Zane and K. Wu},
  journal={Monthly Notices of the Royal Astronomical Society},
  • R. Mignani, V. Testa, K. Wu
  • Published 26 October 2016
  • Physics
  • Monthly Notices of the Royal Astronomical Society
The ‘Magnificent Seven’ (M7) are a group of radio-quiet isolated neutron stars discovered in the soft X-rays through their purely thermal surface emission. Owing to the large inferred magnetic fields (B ≈ 1013 G), radiation from these sources is expected to be substantially polarized, independently of the mechanism actually responsible for the thermal emission. A large observed polarization degree (PD) is, however, expected only if quantum-electrodynamic (QED) polarization effects are present… 

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