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TESS photometry of extreme helium stars PV Tel and V821 Cen

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 نشر من قبل Simon Jeffery
 تاريخ النشر 2020
  مجال البحث فيزياء
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PV Tel variables are extreme helium (EHe) stars known to be intrinsic light and velocity variable on characteristic timescales 0.1 - 2 d. With two exceptions, they are best described as irregular. Light curves have invariably been obtained from single-site terrestrial observatories. We present TESS observations of two bright EHe stars, Poppers star (V821 Cen) and Thackerays star (PV Tel). PV Tel is variable on timescales previously reported. V821 Cen is proven to be variable for the first time. Neither light curve shows any evidence of underlying regularity. Implications are considered.



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