J/A+A/450/763 Evolutionary state of magnetic CP stars (Kochukhov+, 2006)
Evolutionary state of magnetic chemically peculiar stars.
Kochukhov O., Bagnulo S.
<Astron. Astrophys., 450, 763-775 (2006)>
=2006A&A...450..763K 2006A&A...450..763K
ADC_Keywords: Stars, peculiar ; Magnetic fields ; Stars, masses
Keywords: stars: chemically peculiar - stars: evolution -
stars: fundamental parameters - stars: magnetic fields
Abstract:
The photospheres of about 5-10% of the upper main sequence stars
exhibit remarkable chemical anomalies. Many of these chemically
peculiar (CP) stars have a global magnetic field, the origin of which
is still a matter of debate. We present a comprehensive statistical
investigation of the evolution of magnetic CP stars, aimed at
providing constraints to the theories that deal with the origin of the
magnetic field in these stars.
Description:
We have collected from the literature data for 150 magnetic CP stars
with accurate Hipparcos parallaxes. We have retrieved from the ESO
archive 142 FORS1 observations of circularly polarized spectra for 100
stars. From these spectra we have measured the mean longitudinal
magnetic field, and discovered 48 new magnetic CP stars (five of which
belonging to the rare class of rapidly oscillating Ap stars). We have
determined effective temperature and luminosity, then mass and
position in the H-R diagram for a final sample of 194 magnetic CP
stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 142 <Bz> measurements for the sample of CP stars
observed with FORS1 (data retrieved from the
ESO archive)
table2.dat 93 194 Fundamental parameters of magnetic CP stars
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See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
III/162 : General Catalogue of Ap and Am stars (Renson+ 1991)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD (III/135) number
9- 14 I6 --- HIP ? HIP (I/239) number
17- 19 F3.1 mag Vmag V magnitude (1)
21- 33 A13 --- SpType MK spectral type (1)
35- 45 F11.3 d JD Julian date of the middle of the exposure
47- 51 I5 10-4T <Bz> Longitudinal magnetic field, in Gauss
53- 55 I3 10-4T e_<Bz> rms uncertainty on <Bz>
57- 58 A2 --- n_<Bz> [NCD ] Note for stars for which magnetic field
was detected for the first time (2)
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Note (1): V-magnitude and spectral type, most of which are extracted
from the General catalogue of Ap and Am stars by Renson et al.
(1991, Cat. III/162).
Note (2): Note as follows:
ND = new detection
CD = confirmed detection
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- HD HD (III/135) number
8- 13 I6 --- HIP HIP (I/239) number
15- 17 I3 pc Dist Distance
19- 20 I2 pc e_Dist rms uncertainty on Dist
22- 26 F5.2 mag VMAG Absolute V magnitude
28- 31 F4.2 mag e_VMAG rms uncertainty on VMAG
33- 37 F5.3 [K] logTeff Effective temperature
39- 43 F5.3 [K] e_logTeff rms uncertainty on Teff
45- 48 F4.2 [solLum] logL Luminosity
50- 53 F4.2 [solLum] e_logL rms uncertainty on logL
55- 58 F4.2 solMass Mass Mass
60- 63 F4.2 solMass e_Mass rms uncertainty on Mass
65- 68 F4.2 [yr] logt Absolute stellar age
70- 73 F4.2 [yr] logtL Lower limit of 1sigma error interval
on logt (1)
74 A1 --- --- [-]
75- 78 F4.2 [yr] logtU Upper limit of 1sigma error interval
on logt (1)
80- 83 F4.2 --- tau Fractional stellar age
85- 88 F4.2 --- tauL Lower limit of 1sigma error interval
on tau (1)
89 A1 --- --- [-]
90- 93 F4.2 --- tauU Upper limit of 1sigma error interval
on tau (1)
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Note (1): Error interval compatible with the errors of Teff and L.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 04-Dec-2006