Bibcode
Brunsden, E.; Pollard, K. R.; Cottrell, P. L.; Uytterhoeven, K.; Wright, D. J.; De Cat, P.
Bibliographical reference
Monthly Notices of the Royal Astronomical Society, Volume 447, Issue 3, p.2970-2980
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3
2015
Citations
13
Refereed citations
9
Description
Hybrid stars of the γ Doradus and δ Scuti pulsation types
have great potential for asteroseismic analysis to explore their
interior structure. To achieve this, mode identifications of pulsational
frequencies observed in the stars must be made, a task which is far from
simple. In this work we begin the analysis by scrutinizing the
frequencies found in the CoRoT photometric satellite measurements and
ground-based high-resolution spectroscopy of the hybrid star HD 49434.
The results show almost no consistency between the frequencies found
using the two techniques and no characteristic period spacings or
couplings were identified in either data set. The spectroscopic data
additionally show no evidence for any long-term (5 yr) variation in the
dominant frequency. The 31 spectroscopic frequencies identified have
standard deviation profiles suggesting multiple modes sharing (l, m) in
the δ Scuti frequency region and several skewed modes sharing the
same (l, m) in the γ Doradus frequency region. In addition, there
is a clear frequency in the γ Doradus frequency region that
appears to be unrelated to the others. We conclude HD 49434 remains a
δ Scuti/γ Doradus candidate hybrid star but more
sophisticated models dealing with rotation are sought to obtain a clear
picture of the pulsational behaviour of this star.