First evidence of a magnetic field on Vega Towards a new class of magnetic A-type stars ⋆

  title={First evidence of a magnetic field on Vega Towards a new class of magnetic A-type stars ⋆},
  author={François Ligni{\`e}res and Pascal Petit and Torsten Bohm and Michel Auri{\`e}re},
  journal={Astronomy and Astrophysics},
Aims. We report the detection of a magnetic field on Vega through spe ctropolarimetric observations. Methods. We acquired 257 Stokes V, high signal-to-noise and high-resolution echelle spectra during four consecutive nights wit h the NARVAL spectropolarimeter at the 2-m Telescope Bernard Lyot of Observatoire du Pic du Midi (France). A circularly polarized signal in line profiles is unambiguously detected after comb ining the contribution of about 1200 spectral lines for each spectrum and… 

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