J/A+A/475/1053 Magnetic fields in Ap/Bp stars (Auriere+, 2007)
Weak magnetic fields in Ap/Bp stars: Evidence for a dipole field lower limit
and a tentative interpretation of the magnetic dichotomy.
Auriere M., Wade G.A., Silvester J., Lignieres F., Bagnulo S., Bale K.,
Dintrans B., Donati J.F., Folsom C.P., Gruberbauer M., Hui Bon Hoa A.,
Jeffers S., Johnson N., Landstreet J.D., Lebre A., Lueftinger T.,
Marsden S., Mouillet D., Naseri S., Paletou F., Petit P., Power J.,
Rincon F., Strasser S., Toque N.
<Astron. Astrophys. 475, 1053 (2007)>
=2007A&A...475.1053A 2007A&A...475.1053A
ADC_Keywords: Stars, peculiar ; Magnetic fields
Keywords: stars: chemically peculiar - stars: magnetic field
Abstract:
We have investigated a sample of 28 well-known
spectroscopically-identified magnetic Ap/Bp stars, with weak,
poorly-determined or previously undetected magnetic fields. The aim of
this study is to explore the weak part of the magnetic field
distribution of Ap/Bp stars. Using the MuSiCoS and NARVAL
spectropolarimeters at Telescope Bernard Lyot (Observatoire du Pic
du Midi, France) and the cross-correlation technique Least Squares
Deconvolution (LSD), we have obtained 282 LSD Stokes $V$ signatures of
our 28 sample stars, in order to detect the magnetic field and to
infer its longitudinal component with high precision (median
sigma=40G).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 50 28 Star positions
table3.dat 67 282 Dates, magnetic field detection and longitudinal
magnetic field measurements
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See also:
III/162 : General Catalogue of Ap and Am stars (Renson+ 1991)
J/A+A/407/631 : Catalogue of stellar effective magnetic fields (Bychkov+, 2003)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [HD]
4- 9 I6 --- HD HD number
11- 12 I2 h RAh Simbad Hour of Right Ascension (J2000.0)
14- 15 I2 min RAm Simbad Minute of Right Ascension (J2000.0)
17- 18 I2 s RAs Simbad Second of Right Ascension (J2000.0)
20 A1 --- DE- Simbad Sign of the Declination (J2000.0)
21- 22 I2 deg DEd Simbad Degree of Declination (J2000.0)
24- 27 F4.1 arcmin DEm Simbad Arcminute of Declination (J2000.0)
29- 33 F5.3 mag Bmag Simbad B band magnitude
35- 39 F5.3 mag Vmag Simbad V band magnitude
41- 50 A10 --- SpType Simbad MK spectral type
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Name
14- 19 I6 --- HD HD number
22- 31 A10 "DD/MM/YYYY" Date Date
33- 42 F10.2 d JD Julian Date
44- 47 I4 --- S/N Signal to Noise ratio
49- 55 F7.3 --- chi2 chi2 value
57- 58 A2 --- Det Quality of detection (1)
60- 63 I4 10-4T Bl Longitudinal magnetic field (gauss)
65- 67 I3 10-4T e_Bl rms uncertainty on Bl
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Note (1): Detection as follows:
DD = Definitive Detection
md = Marginal Detection
nd = Non Detection
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Acknowledgements:
Michel Auriere,
(End) Michel Auriere [Obs. Midi Pyrenees], Patricia Vannier [CDS] 16-Oct-2007