Bibcode
Reed, M. D.; Baran, A. S.; Østensen, R. H.; Telting, J. H.; Kern, J. W.; Bloemen, S.; Blay, P.; Pursimo, T.; Kuutma, T.; Slumstrup, D.; Saajasto, M.; Nielsen, L. D.; Harmanen, J.; Winans, A. J.; Foster, H. M.; Rowe, L.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 458, Issue 2, p.1417-1426
Advertised on:
5
2016
Citations
21
Refereed citations
20
Description
We report a new subdwarf B pulsator, PG 1142-037, discovered during the
first full-length campaign of K2, the two-gyro mission of the Kepler
space telescope. 14 periodicities have been detected between 0.9 and 2.5
hr with amplitudes below 0.35 parts-per-thousand. We have been able to
associate all of the pulsations with low-degree, ℓ ≤ 2 modes.
Follow-up spectroscopy of PG 1142 has revealed it to be in a binary with
a period of 0.54 d. Phase-folding the K2 photometry reveals a
two-component variation including both Doppler boosting and ellipsoidal
deformation. Perhaps the most surprising and interesting result is the
detection of an ellipsoidal, tidally distorted variable with no
indication of rotationally induced pulsation multiplets. This indicates
that the rotation period is longer than 45 d, even though the binary
period is near 13 h.