J/A+AS/120/127 UBVRI photometry of 7 dwarfs in Alpha Per (Bouvier 1996)
UBVRI photometric monitoring of 7 rapidly rotating late-type dwarfs in the
Alpha Persei cluster
Bouvier J.
<Astron. Astrophys. Suppl. Ser. 120, 127 (1996)>
=1996A&AS..120..127B 1996A&AS..120..127B
ADC_Keywords: Stars, dwarfs ; Photometry, UBVRI
Keywords: stars: magnetic fields - stars: rotation - stars: activity -
stars: late type -
open clusters and associations: individual: Alpha Persei
Description:
The UBVRI light curves of 7 late-type dwarfs amongst the fastest
rotators of the Alpha Per cluster (vsini≥140km/s) are presented. The
shape of the light curves suggests that the photometric variations are
most often dominated by a single group of cool spots located at
intermediate or high latitude on the stellar surface. Assuming that
starspots are good tracers of the stellar magnetic field, the smooth
light curves indicate the existence of a large scale, slowly varying
magnetic structure at the surface of these ultrafast rotators.
For a description of the UBVRI photometric system, see e.g. GCPD/08
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 44 7 List of stars
table.dat 44 434 UBVRI photometry
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Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- name Name of star in alpha Per (Mel 20), as in table
8- 9 I2 h RAh Right Ascension J2000 (hours) (1)
11- 12 I2 min RAm Right Ascension J2000 (minutes) (1)
14- 17 F4.1 s RAs Right Ascension J2000 (seconds) (1)
19 A1 --- DE- Declination J2000 (sign) (1)
20- 21 I2 deg DEd Declination J2000 (degrees) (1)
23- 24 I2 arcmin DEm Declination J2000 (minutes) (1)
26- 27 I2 arcsec DEs Declination J2000 (seconds) (1)
30- 34 F5.2 mag Vmag Mean visual magnitude (1) (1)
37- 44 A8 --- Vname Variable name (1)
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Note (1): from Simbad data-base
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Byte-by-byte Description of file: table.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- name Star name
7- 17 F11.3 d HJD Heliocentric Julian date
19- 30 E12.5 mag Mag Differential magnitude
32- 42 E11.5 mag e_Mag rms error on the magnitude
44 A1 --- Color [UBVRI] Filter
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History:
* 03-May-1996: first version
* 24-Jan-2004: added the file "stars.dat" at CDS.
Acknowledgements: Jerome Bouvier
(End) Patricia Bauer [CDS] 03-May-1996