Bibcode
Derekas, A.; Kiss, L. L.; Bedding, T. R.; Ashley, M. C. B.; Csák, B.; Danos, A.; Fernandez, J. M.; Fűrész, G.; Mészáros, Sz.; Szabó, Gy. M.; Szakáts, R.; Székely, P.; Szatmáry, K.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 394, Issue 2, pp. 995-1008.
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4
2009
Citations
33
Refereed citations
29
Description
We have carried out a photometric and spectroscopic survey of bright
high-amplitude δ Scuti (HADS) stars. The aim was to detect
binarity and multiperiodicity (or both) in order to explore the
possibility of combining binary star astrophysics with stellar
oscillations. Here, we present the first results for 10, predominantly
southern, HADS variables. We detected the orbital motion of RS Gru with
a semi-amplitude of ~6.5 kms-1 and 11.5 d period. The
companion is inferred to be a low-mass dwarf star in a close orbit
around RS Gru. We found multiperiodicity in RY Lep from both photometric
and radial velocity data and detected orbital motion in the radial
velocities with hints of a possible period of 500-700 d. The data also
revealed that the amplitude of the secondary frequency is variable on
the time-scale of a few years, whereas the dominant mode is stable.
Radial velocities of AD CMi revealed cycle-to-cycle variations, which
might be due to non-radial pulsations. We confirmed the multiperiodic
nature of BQ Ind, while we obtained the first radial velocity curves of
ZZ Mic and BE Lyn. The radial velocity curve and the O-C diagram of CY
Aqr are consistent with the long-period binary hypothesis. We took new
time series photometry on XX Cyg, DY Her and DY Peg, with which we
updated their O-C diagrams.