J/A+A/531/A143 Rotational velocities of HR stars (Diaz+, 2011)
Accurate stellar rotational velocities using the Fourier transform of the
cross correlation maximum.
Diaz C.G., Gonzalez J.F., Levato H., Grosso M.
<Astron. Astrophys., 531, A143 (2011)>
=2011A&A...531A.143D 2011A&A...531A.143D
ADC_Keywords: Stars, nearby ; Rotational velocities
Keywords: stars: fundamental parameters - stars: rotation -
methods: data analysis
Abstract:
We propose a method for measuring the projected rotational velocity
vsini with high precision even in spectra with blended lines. Though
not automatic, our method is designed to be applied systematically to
large numbers of objects without excessive computational requirement.
We calculated the cross correlation function (CCF) of the object
spectrum against a zero-rotation template and used the Fourier
transform (FT) of the CCF central maximum to measure the parameter
vsini taking the limb darkening effect and its wavelength dependence
into account. The procedure also improves the definition of the CCF
base line, resulting in errors related to the continuum position under
1% even for vsini=280km/s. Tests with high-resolution spectra
of F-type stars indicate that an accuracy well below 1% can be
attained even for spectra where most lines are blended.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 38 251 Results for 251 A1-A5 stars from the Bright Star
Catalogue in the southern hemisphere
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See also:
V/50 : Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)
III/135 : Henry Draper Catalogue and Extension (Cannon+ 1918-1924; ADC 1989)
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 number, Cat. III/135
8- 12 F5.1 km/s Mean rotational velocity
14- 16 F3.1 km/s err1 First method rms uncertainty on (1)
18- 22 F5.2 km/s err2 Second method rms uncertainty on (2)
24- 38 A15 --- SpType MK spectral type
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Note (1): Standard deviation of the weighted mean of a sample of n
uncorrelated observations with standard deviations ei.
Note (2): Standard error of the mean σ/sqrt(n) for a set of
measurements weighted according to their individual errors.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 28-Oct-2011