J/A+AS/127/277 Rotation and binary rate among giant F stars (Kunzli+ 1998)
Are metallic A-F giants evolved Am stars?
Rotation and rate of binaries among giant F stars
Kuenzli M., North P.
<Astron. Astrophys. Suppl. Ser. 127, 277 (1998)>
=1998A&AS..127..277K 1998A&AS..127..277K (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, spectroscopic ; Stars, F-type ; Stars, giant ;
Radial velocities
Keywords: stars: binaries: spectroscopic - stars: chemically peculiar -
stars: evolution - stars: rotation - stars: Delta Scuti
Description:
We have tested the hypothesis of Berthet (1991A&A...251..171B 1991A&A...251..171B) which
foresees that Am stars become giant metallic A and F stars (defined by
an enhanced value of the blanketing parameter δm2 of the Geneva
photometry) when they evolved. If this hypothesis is right, Am and
metallic A-FIII stars need to have the same rate of binaries and a
similar distribution of vsini. From our new spectroscopic data and
from vsini and radial velocities in the literature, we show that it is
not the case. The metallic giant stars are often fast rotators with
vsini larger than 100 km/s, while the maximum rotational velocity for
Am stars is about 100 km/s. The rate of tight binaries with periods
less than 1000 days is less than 30 % among metallic giants, which is
incompatible with the value of 75 % for Am stars (Abt & Levy,
1985ApJS...59..229A 1985ApJS...59..229A). Therefore, the simplest way to explain the
existence of giant metallic F stars is to suggest that all normal A
and early F stars might go through a short "metallic" phase when they
are finishing their life on the main sequence. Besides, it is shown
that only giant stars with spectral type comprised between F0 and F6
may have a really enhanced δm2 value, while all A-type giants
seem to be normal.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2 30 54 Radial velocities of standard stars
table3 30 236 Radial velocities of A and F giants
table6 80 148 Discussion about the duplicity of all
photometric metallic F giant stars of
Hauck (1986A&A...155..371H 1986A&A...155..371H)
tables.tex 147 901 LaTeX version of the tables
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Byte-by-byte Description of file: table2 table3
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD number (1)
8- 18 F11.3 d HJD Heliocentric Julian day
20- 25 F6.2 km/s RV Radial velocity
27- 30 F4.2 km/s e_RV rms uncertainty on RV
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Note (1): Average values of radial velocity for table2 stars:
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Star <Vr>
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HD 693 15.44±0.36
HD 22484 27.86±0.44
HD 89449 5.84±0.52
HD 114762 47.77±0.26
HD 136202 54.39±0.27
HD 187691 -0.27±0.49
HD 222368 5.12±0.45
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Byte-by-byte Description of file: table6
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- Name ? HD number
8- 9 I2 --- NTot Total number of lines for the reference
11- 12 I2 --- Nline Running line number in range [1,Ntot]
14- 80 A67 --- Com Comments (1)
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Note (1): References:
Abt (1965ApJS...11..429A 1965ApJS...11..429A)
Abt (1969ApJS...19..387A 1969ApJS...19..387A)
Abt & Biggs, 1972, Bibliography of Stellar Radial Velocities,
Latham Process Corp., New York
Abt & Levy (1976ApJS...30..273A 1976ApJS...30..273A)
Adams et al. (1929ApJ....70..207A 1929ApJ....70..207A)
Breger (1979PASP...91....5B 1979PASP...91....5B)
Buscombe & Morris (1958MNRAS.118..609B 1958MNRAS.118..609B)
Campbell (1913LicOB...7..113C 1913LicOB...7..113C)
Campbell (1928PLicO..16.....C 1928PLicO..16.....C)
Cannon (1920PDO.....4..253C 1920PDO.....4..253C)
Catchpole et al. (1982RGOB..188....5C 1982RGOB..188....5C)
Evans (1961RGOB...44..351E 1961RGOB...44..351E)
Evans (1966RGOB..110..185E 1966RGOB..110..185E)
Evans et al. (1961RGOB...48..389E 1961RGOB...48..389E)
Evans et al. (1964RGOB...85..207E 1964RGOB...85..207E)
Evans et al. (1957MNRAS.117..534E 1957MNRAS.117..534E)
Frost et al. (1929PYerO...7....1F 1929PYerO...7....1F)
Harper (1937PDAO....7....1H 1937PDAO....7....1H)
Henroteau (1923PDO.....8...59H 1923PDO.....8...59H)
Jones & Haslam (1969RGOB..155...19J 1969RGOB..155...19J)
Mayor & Mazeh (1987A&A...171..157M 1987A&A...171..157M)
Nelson & Kreidl (1993AJ....105.1903N 1993AJ....105.1903N)
Neubauer (1930LicOB..15...47N 1930LicOB..15...47N)
Nordstroem & Andersen (1985A&AS...61...53N 1985A&AS...61...53N, Cat. III/127)
Penfold (1971PASP...83..497P 1971PASP...83..497P)
Rodriguez et al. (1994A&AS..106...21R 1994A&AS..106...21R)
Rosvick & Scarfe (1991PASP..103..628R 1991PASP..103..628R)
Sanford & Karr (1942ApJ....96..214S 1942ApJ....96..214S)
Shajn & Albitzky (1932MNRAS..92..771S 1932MNRAS..92..771S)
Smith (1982ApJ...254..242S 1982ApJ...254..242S)
Wilson & Joy (1950ApJ...111..221W 1950ApJ...111..221W)
Wooley et al. (1971ROAn...14....1W 1971ROAn...14....1W)
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Acknowledgements: Marc Kunzli
(End) Francois Ochsenbein [CDS] 15-Jul-1997