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Doppler maps and surface differential rotation of EI Eri from the MUSICOS 1998 observations

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 نشر من قبل Kriszti\\'an Vida
 تاريخ النشر 2008
  مجال البحث فيزياء
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We present time-series Doppler images of the rapidly-rotating active binary star EI Eri from spectroscopic observations collected during the MUSICOS multi-site campaign in 1998, since the critical rotation period of 1.947 days makes it impossible to obtain time-resolved images from a single site. From the surface reconstructions a weak solar-type differential rotation, as well as a tiny poleward meridional flow are measured.

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