The Discovery of Stellar Oscillations in the K Giant ι Dra

نویسنده

  • Andreas Quirrenbach
چکیده

ι Dra (HIP 75458) is a well-known example for a K giant hosting a substellar companion since its discovery by Frink et al. (2002). We present radial velocity measurements of this star from observations taken with three different instruments spanning nearly 8 years. They show more clearly that the RV period is long-lived and coherent thus supporting the companion hypothesis. The longer time baseline now allows for a more accurate determination of the orbit with a revised period of P = 511 d and an additional small linear trend, indicative of another companion in a wide orbit. Moreover we show that the star exhibits low amplitude, solar like oscillations with frequencies around 3-4 d−1 (34.7-46.3 μHz).

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تاریخ انتشار 2008