Aldebaran b's temperate past uncovered in planet search data

Research output: Contribution to journalArticlepeer-review

Authors

  • Benjamin J. S. Pope
  • Thomas S. H. North
  • Timothy R. White
  • Jim W. Barrett
  • Victoria Antoci
  • Mads Fredslund Andersen
  • Frank Grundahl
  • Daniel Huber

Colleges, School and Institutes

Abstract

The nearby red giant Aldebaran is known to host a gas giant planetary companion from decades of ground-based spectroscopic radial velocity measurements. Using Gaussian Process-based Continuous Auto-Regressive Moving Average models, we show that these historic data also contain evidence of acoustic oscillations in the star itself, and verify this result with further dedicated ground-based spectroscopy using the SONG telescope and space-based photometry with the Kepler Space Telescope. From the frequency of these oscillations we determine the mass of Aldebaran to be 1.16 ± 0.07 M, and note that this implies its planet will have been subject to insolation comparable to the Earth for some of the star's main sequence lifetime. Our approach to sparse, irregularly sampled time series astronomical observations has the potential to unlock asteroseismic measurements for thousands of stars in archival data, and push to lower-mass planets around red giant stars.

Bibliographic note

24 pages, 7 figures (including appendices); submitted to ApJL; paper text, figures, data, and code at https://github.com/farr/Aldebaran

Details

Original languageEnglish
Article numberL20
Number of pages12
JournalThe Astrophysical Journal
Volume865
Issue number2
Early online date27 Sep 2018
Publication statusPublished - 1 Oct 2018

Keywords

  • astro-ph.SR, astro-ph.EP, methods: data analysis, methods: statistical, planets and satellites: individual (Aldebaran b), stars: individual (Aldebaran), stars: oscillations (including pulsations), techniques: radial velocities