IA/U.Porto Cookie Seminar - RV variability in evolved stars: planets, oscillations or stellar activity? - 20 março 2018

RV variability in evolved stars: planets, oscillations or stellar activity?

Our ability to detect planets around stars with the radial-velocity (RV) method has a strong dependence on our understanding of the stellar jitter of such stars which can reach dozens of m/s in red giants. This intrinsic RV variability can be caused by stellar magnetic activity, pulsations or granulation and it behaves on a different way depending on the spectral type of the stars and on their evolutionary stage. In this work we present RV signals in 3 evolved massive stars (2-4 solar masses) which mimic long-period planets (P~700 days). We discuss the possibility of whether we might be facing a new kind of stellar pulsations or the RV variability is caused by stellar activity.

 

IA/U.Porto