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Interferometric and spectroscopic observations of the BRITE target Delta Cep

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 نشر من قبل Ennio Poretti
 تاريخ النشر 2017
  مجال البحث فيزياء
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 تأليف Ennio Poretti




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We used new HARPS-N spectra to revisitate the projection factor of Delta Cep and to directly measure the specific contribution of the velocity gradient within the atmosphere. By introducing an hydrodynamical model we could also determine the semi-theoretical values of the correction factor between the gas movement and the optical continuum by assuming radiative transfer in plane-parallel or sherically symmetric geometries, respectively.



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