Probing Polaris’ puzzling radial velocity signals

@article{Anderson2019ProbingPP,
  title={Probing Polaris’ puzzling radial velocity signals},
  author={Richard I. Anderson},
  journal={Astronomy \& Astrophysics},
  year={2019}
}
  • R. Anderson
  • Published 21 February 2019
  • Physics, Geology
  • Astronomy & Astrophysics
We investigate temporally changing variability amplitudes and the multi-periodicity of the type-I Cepheid Polaris using 161 high-precision radial velocity (RV) and bisector inverse span (BIS) measurements based on optical spectra recorded using Hermes at the 1.2 m Flemish Mercator telescope on La Palma, Canary Islands, Spain. Using an empirical template fitting method, we show that Polaris’ RV amplitude has been stable to within ∼30 m s−1 between September 2011 and November 2018. We apply the… 
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