J/A+AS/145/275 uvby phot. of suspected beta Pic-like stars (Nitschelm+, 2000)
A three-years Stroemgren photometric survey of suspected
beta Pictoris-like stars
Nitschelm C., Lecavelier des Etangs A., Vidal-Madjar A., Ferlet R.,
Olsen E.H.
<Astron. Astrophys. Suppl. Ser. 145, 275 (2000)>
=2000A&AS..145..275N 2000A&AS..145..275N
ADC_Keywords: Stars, variable ; Photometry, uvby
Keywords: stars: beta Pic - circumstellar matter - planetary systems -
Stroemgren photometry
Abstract:
We carried out a Stroemgren photometric survey of thirteen southern
bright stars, including β Pictoris itself, during three years,
d'Astrophysique de Paris, in order to detect possible weak photometric
variations. β Pictoris presents a small long-term variation with
a change of brightness by -2.1x10-3mag per year, over about two
years from beginning of 1996, a situation relatively similar to the
one about 18 years ago. Among the other stars, only HD 38392 presents
weak photometric variations with a period of 21.4 days, probably
related to the star rotation period. The negative result concerning
photometric variations of all other stars suggests that those stars
are actually really stable and strengthens the reality of the
variations discovered in the case of β Pictoris and HD 38392.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 34 34 Star positions (from Simbad)
tables.dat 54 6655 Stroemgren photometric data of Beta
Pictoris-like stars and their comparison stars
used to analyse the data
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See also:
J/A+A/299/557 : Light variations on Beta Pic (Lecavelier des Etangs+, 1995)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD (Cat. III/135) number
9- 10 I2 h RAh Right ascension (J2000.0)
12- 13 I2 min RAm Right ascension (J2000.0)
15- 18 F4.1 s RAs Right ascension (J2000.0)
20 A1 --- DE- Declination sign (J2000.0)
21- 22 I2 deg DEd Declination (J2000.0)
24- 25 I2 arcmin DEm Declination (J2000.0)
27- 28 I2 arcsec DEs Declination (J2000.0)
30- 34 A5 --- Years Two last digits of the years of the beginning
and the end of the survey (for each star)
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Byte-by-byte Description of file: tables.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number of the star
8- 21 F14.6 d HJD Heliocentric Julian date
23- 29 F7.5 --- Airmass Airmass of observation
31- 35 F5.3 mag Vmag Stroemgren V magnitude
37- 42 F6.3 mag b-y Stroemgren (b-y) colour index
44- 48 F5.3 mag m1 Stroemgren m1 colour-index difference
50- 54 F5.3 mag c1 Stroemgren c1 colour-index difference
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Acknowledgements: Alain Lecavelier
(End) Patricia Bauer [CDS] 27-Nov-2000