J/A+A/542/A55 Analysis of the B3IV star HD 43317 (Papics+, 2012)
Gravito-inertial and pressure modes detected in the B3 IV CoRoT target HD 43317.
Papics P.I., Briquet M., Baglin A., Poretti E., Aerts C., Degroote P.,
Tkatchenko A., Morel T., Zima W., Niemczura E., Rainer M., Hareter M.,
Baudin F., Catala C., Michel E., Samadi R., Auvergne M.
<Astron. Astrophys. 542, A55 (2012)>
=2012A&A...542A..55P 2012A&A...542A..55P
ADC_Keywords: Stars, variable ; Stars, B-type
Keywords: asteroseismology - stars: variables: general - stars: abundances -
stars: oscillations - stars: individual: HD 43317 - stars: rotation
Abstract:
OB stars are important building blocks of the Universe, but we have
only a limited sample of them well understood enough from an
asteroseismological point of view to provide feedback on the current
evolutionary models. Our study adds one special case to this sample,
with more observational constraints than for most of these stars.
Our goal is to analyse and interpret the pulsational behaviour of the
B3 IV star HD 43317 using the CoRoT light curve along with the
ground-based spectroscopy gathered by the Harps instrument. This way
we continue our efforts to map the Beta Cep and SPB instability
strips.
We used different techniques to reveal the abundances and fundamental
stellar parameters from the newly-obtained high-resolution spectra. We
used various time-series analysis tools to explore the nature of
variations present in the light curve. We calculated the moments and
used the pixel-by-pixel method to look for line profile variations in
the high- resolution spectra.
We find that HD 43317 is a single fast rotator (vrot∼50%vcrit)
and hybrid SPB/Beta Cep-type pulsator with Solar metal abundances. We
interpret the variations in photometry and spectroscopy as a result of
rotational modulation connected to surface inhomogeneities, combined
with the presence of both g and p mode pulsations. We detect a series
of ten consecutive frequencies with an almost constant period spacing
of 6339s as well as a second shorter sequence consisting of seven
frequencies with a spacing of 6380s. The dominant frequencies fall in
the regime of gravito- inertial modes.
Description:
Table A.1. Fourier parameters (frequencies (fj), amplitudes (Aj),
and phases (thetaj)) of peaks which are common in both halves of the
data (marked with a 1 in the note column), as well as additional ones
which have a S/N ratio above 4 when computed over the full
periodogram. The displayed S/N values are calculated in a window of
1d-1 or 3d-1 centred on the given frequency, or from the full
periodogram (from 0d-1 to 20d-1).
Objects:
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RA (2000) DE Designation(s)
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06 15 47.01 +04 17 01.1 HD 43317 = HR 2232
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 116 424 Fourier parameters
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See also:
B/corot : CoRoT observation log Release 8 (CoRoT, 2012)
J/A+A/482/L17 : CoRoT space mission. I. (Barge+, 2008)
J/A+A/506/471 : Frequency analysis of CoRoT B stars (Degroote+, 2009)
J/A+A/525/A23 : Frequency analysis of HD 49434 (Mathias+, 2011)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 10 F10.6 d-1 Freq Frequency from Fourier analysis
16- 23 F8.6 d-1 e_Freq Frequency error
27- 33 F7.1 10-6 Amp Amplitude, in ppm (part per million)
40- 43 F4.1 10-6 e_Amp Amplitude error, in ppm (part per million)
48- 54 F7.4 --- Phase [-0.5/0.5] Phase (2π/rad)
59- 65 F7.4 --- e_Phase Phase error
69- 73 F5.1 --- S/N1 Signal-to-noise in a 1d-1 wide window
around Freq
77- 81 F5.1 --- S/N3 Signal-to-noise in a 3d-1 wide window
around Freq
85- 89 F5.1 --- S/Nf Signal-to-noise computed over full periodogram
97-116 A20 --- Notes Notes (frot is the rotational frequency)
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Acknowledgements:
Peter I. Papics, Peter.Papics(at)ster.kuleuven.be
(End) P. Papics [Inst. Sterrenkunde, KU Leuven], P. Vannier [CDS] 26-Mar-2012