J/A+A/506/79 Asteroseismic analysis of HD 174936 (Garcia Hernandez+, 2009)
Asteroseismic analysis of the CoRoT δ-Scuti star HD 174936.
Garcia Hernandez A., Moya A., Michel E., Garrido R., Suarez J.C.,
Rodriguez E., Amado P.J., Martin-Ruiz S., Rolland A., Poretti E., Samadi R.,
Baglin A., Auvergne M., Catala C., Lefevre L., Baudin F.
<Astron. Astrophys. 506, 79 (2009)>
=2009A&A...506...79G 2009A&A...506...79G
ADC_Keywords: Stars, variable ; Spectroscopy
Keywords: stars: variables: δ Sct - stars: rotation -
stars: oscillations - stars: fundamental parameters - stars: interiors
Abstract:
We present an analysis of the δ-Scuti star HD 174936 (ID 7613)
observed by CoRoT during the first short run SRc01 (27 days). A total
number of 422 frequencies were extracted from the light curve using
standard prewhitening techniques. This number of frequencies was
obtained by considering a spectral significance limit of sig=10 using
the software package SigSpec. Our analysis of the oscillation
frequency spectrum reveals a spacing periodicity around 52muHz.
Although modes considered here are not in the asymptotic regime, a
comparison with stellar models confirms that this signature may stem
from a quasi-periodic pattern similar to the so-called large
separation in solar-like stars.
Description:
We have used the program package SigSpec (Reegen 2007A&A...467.1353R 2007A&A...467.1353R).
We performed iterations until the limit of sig=10.0 for spectral
significance (not sig=5.0 as used as default in SigSpec) because the
corresponding S/N values in our data (as determined later using
Period04 on the residuals provided by SigSpec) were much lower than
expected.
Objects:
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RA (2000) DE Designation(s)
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18 52 58.9 +02 49 51 HD 174936 = TYC 453-219-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 82 422 List of peaks detected for HD174936 in the
frequency region 0.05-100c/d until sig=10.0
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See also:
B/corot : CoRoT observation log (CoRoT, 2009)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequence number of the peak, in the same order
that this was detected
5- 15 F11.8 d-1 Freq Frequency
17- 22 F6.4 mmag Amp Amplitude
24- 32 F9.6 rad Phase [-3.14,3.14] Phase
34- 41 F8.3 --- Sig Significance of frequency (1)
43- 50 F8.4 --- S/N Signal to noise ratio (2)
51- 55 F5.3 mmag rms rms for frequency "Seq" (3)
57- 66 F10.8 d-1 e_Freq Formal error on freq (4)
68- 73 F6.4 mmag e_Amp Formal error on Amp (4)
75- 82 F8.6 rad e_Phase Formal error on Phase (4)
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Note (1): As defined by Reegen, 2007A&A...467.1353R 2007A&A...467.1353R.
Note (2): Calculated using Period04 (Lenz & Breger 2005, CoAst 146, 5) on
the residuals provided by SigSpec. Each S/N value was calculated on a
box of width=5c/d centred in the corresponding peak, as usual in a
number of papers of Breger et al.
Note (3): sigma of the residuals before extracting the peak "Seq"
Note (4): Determined using the formulae of Montgomery & O'Donoghue (1999,
DSSN 13, 28).
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Acknowledgements:
Antonio Garcia Hernandez, agh(at)iaa.es
(End) Patricia Vannier [CDS] 24-Jul-2009