J/A+A/506/471 Frequency analysis of CoRoT B stars (Degroote+, 2009)
CoRoT's view on newly discovered B-star pulsators: results for 358 candidate
B pulsators from the initial run's exoplanet field data.
Degroote P., Aerts C., Ollivier M., Miglio A., Debosscher J., Cuypers J.,
Briquet M., Montalban J., Thoul A, Noels A., De Cat P., Balaguer-Nunez L.,
Maceroni C., Ribas I., Auvergne M., Baglin A., Deleuil M., Weiss W.,
Jorda L., Baudin F., Samadi, R.
<Astron. Astrophys. 506, 471 (2009)>
=2009A&A...506..471D 2009A&A...506..471D
ADC_Keywords: Stars, early-type ; Stars, B-type ; Stars, variable
Keywords: methods: data analysis - stars: oscillations -
stars: variable: general
Abstract:
We search for new variable B-type pulsators in the CoRoT data
assembled primarily for planet detection, as part of CoRoT's
Additional Programme. We aim to explore the properties of newly
discovered B-type pulsators from the uninterrupted CoRoT spacebased
photometry and to compare them with those of known members of the
beta Cep and slowly pulsating B star (SPB) classes.
We developed automated data analysis tools which include algorithms
for jump correction, light curve detrending, frequency detection,
frequency combination search and frequency and period spacing search.
Besides numerous new classical slowly pulsating B stars, we find
evidence for a new class of low-amplitude B-type pulsators between the
SPB and delta Sct instability strips, with a very broad range of
frequencies and low amplitudes, as well as several slowly pulsating B
stars with residual excess power at frequencies typically a factor
three above their expected g-mode frequencies.
The frequency data we obtained for numerous new B-type pulsators
represent an appropriate starting point for further theoretical
analyses of these stars, once their effective temperature, gravity,
rotation velocity and abundances will be derived spectroscopically in
the framework of an ongoing FLAMES survey at VLT.
Description:
Results of frequency analyses for 352 candidate B pulsators (candidate
Be stars are ommitted) from CoRoT's initial run. For each star, the
following information is given: frequency number, amplitude + error,
frequency value + error, phase + error. The error values for large
amplitude frequencies can be slightly underestimated, as they are not
corrected for correlation effects. Also given are comments about every
frequency: if they are expected to be due to instrumental effects
(e.g. orbit of the satellite), if they are harmonics or higher order
combinations of previously identified frequencies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 40 352 Star positions
data/* . 352 Frequency analysis for each star
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See also:
B/corot : CoRoT observation log (CoRoT, 2009)
http://idoc-corot.ias.u-psud.fr/index.jsp : CoRoT
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- CoRoT CoRoT star number
11- 17 F7.3 deg RAdeg Right ascension in decimal degrees (J2000)
19- 26 F8.5 deg DEdeg Declination in decimal degrees (J2000)
28- 40 A13 --- FileName Name of the file with frequency analysis in
"data" subdirectory
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Byte-by-byte Description of file: data/*
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Bytes Format Units Label Explanations
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1- 3 I3 --- nr Frequency number
8- 21 F14.10 mmag A Amplitude value
27- 39 F13.10 mmag e_A Mean error on the Amplitude value
44- 57 F14.10 1/d f Frequency value
63- 75 F13.10 1/d e_f Mean error on the frequency value
79- 87 F9.5 --- p ]-0.5,0.5] Phase value (in rad/2pi unit)
91- 99 F9.5 --- e_p Mean error on the phase value (in rad/2pi unit)
103-110 F8.3 --- S/N Signal-to-noise ratio, calculated over 6/d
interval in the relevant periodogram (not the
residual periodogram)
112-186 A75 --- Note Notes about the frequency (TeX format)
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Acknowledgements:
Pieter Degroote, pieter.degroote(at)ster.kuleuven.be
(End) Pieter Degroote [IvS Leuven, Belgium], Patricia Vannier [CDS] 02-Jun-2009