Timing by Stellar Pulsations as an Exoplanet Discovery Method

Abstract

The stable oscillations of pulsating stars can serve as accurate timepieces, which may be monitored for the influence of exoplanets. An external companion gravitationally tugs the host star, causing periodic changes in pulsation arrival times. This method is most sensitive to detecting substellar companions around the hottest pulsating stars, especially compact remnants like white dwarfs and hot subdwarfs, as well as delta Scuti variables (A stars). However, it is applicable to any pulsating star with sufficiently stable oscillations. Care must be taken to ensure that the changes in pulsation arrival times are not caused by intrinsic stellar variability; an external, light-travel-time effect from an exoplanet identically affects all pulsation modes. With more long-baseline photometric campaigns coming online, this method is yielding new detections of substellar companions.

9 pages, 2 figures: Invited review to appear in 'Handbook of Exoplanets,' Springer Reference Works, edited by Hans J. Deeg and Juan Antonio Belmonte

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Cited by in corpus (6)

• A test of the planet-star unipolar inductor for magnetic white dwarfs
• Forward modeling the orbits of companions to pulsating stars from their light travel time variations
• TESS search for substellar companions through pulsation timing of $\delta$ Scuti stars. I. Discovery of companions around Chang 134 and V393 Car
• Pulse Timing Discovery of a Three-Day Companion to the Hot Subdwarf BPM 36430
• The quest for planets around subdwarfs and white dwarfs from Kepler space telescope fields: Part I. Techniques and tests of the methods
• The $\beta$ Pictoris b Hill sphere transit campaign. Paper II: Searching for the signatures of the $\beta$ Pictoris exoplanets through time delay analysis of the $\delta$ Scuti pulsations