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J/A+A/597/A22       Massive O- and B-type stars velocities   (Simon-Diaz+, 2017)

The IACOB project. III. New observational clues to understand macroturbulent broadening in massive O- and B-type stars. Simon-Diaz S., Godart M., Castro N., Herrero A., Aerts C., Puls J., Telting J., Grassitelli L. <Astron. Astrophys. 597, A22 (2017)> =2017A&A...597A..22S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, early-type; Rotational velocities; Equivalent widths Keywords: stars: early-type - stars: fundamental parameters - stars: massive - stars: rotation - stars: oscillations - techniques: spectroscopic Abstract: The term macroturbulent broadening is commonly used to refer to a certain type of non-rotational broadening acting the spectral line profiles of O- and B-type stars. It has been proposed to be a spectroscopic signature of the presence of stellar oscillations; however, we still lack a definitive confirmation of this hypothesis. We aim to provide new empirical clues about macroturbulent spectral line broadening in O- and B-type stars to evaluate its physical origin. We used high-resolution spectra of 430 stars with spectral types in the range O4-B9 (all luminosity classes) compiled in the framework of the IACOB project. We characterized the line broadening of adequate diagnostic metal lines using a combined Fourier transform and goodness-of-fit technique. We performed a quantitative spectroscopic analysis of the whole sample using automatic tools coupled with a huge grid of FASTWIND models to determine their effective temperatures and gravities. We also incorporated quantitative information about line asymmetries into our observational description of the characteristics of the line profiles, and performed a comparison of the shape and type of line-profile variability found in a small sample of O stars and B supergiants with still undefined pulsational properties and B main-sequence stars with variable line profiles owing to a well-identified type of stellar oscillations or to the presence of spots in the stellar surface. Description: The main observational sample discussed in this paper comprises high-resolution, single snapshot spectra of 431 O- and B-type Galactic stars. The IACOB database includes spectra from two different instruments: the FIES and HERMES spectrographs attached to the 2.56m Nordic Optical Telescope and the 1.2m Mercator telescope, respectively. Both instruments provide a complete wavelength coverage between 3800 and 7000Å (9000Å for the case of HERMES spectra), and the associated resolving power (R) of the spectra is 25000, 46000 (FIES) and 85000 (HERMES). By default, all the spectra in the IACOB database are reduced using the corresponding available pipelines (FIEStool and HermesDRS, respectively) and they are normalized by means of our own procedures implemented in IDL. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablea1.dat 80 431 List of stars considered for this paper
See also: J/A+A/562/A135 : Northern Galactic OB stars vsini (Simon-Diaz+, 2014) Byte-by-byte Description of file: tablea1.dat
Bytes Format Units Label Explanations
1- 13 A13 --- Target HD number of the star 15- 31 A17 --- SpType Spectral type (1) 33- 37 A5 --- Line Line used to determine the line-broadening parameters 40- 42 I3 --- S/Nc Signal-to-noise ratio of the adjacent continuum 44- 46 I3 0.1pm EW Equivalent width of the line 48- 50 I3 km/s vsiniF Projected rotational velocity as derived from the Fourier transform (FT) approach 52- 54 I3 km/s vsiniG Projected rotational velocity as derived from the goodness of fit (GOF) approach 56 A1 --- l_vmac Limit flag on vmac 57- 59 I3 km/s vmac Macroturbulent velocity as derived from the goodness of fit (GOF) approach 61- 65 F5.2 --- RSk Relative skewness of the line profile as derived using Eq. 1 in the paper (2) 67- 70 F4.2 --- e_RSk rms uncertainty on RSk 72- 75 F4.2 [K] logTeff ?=- Effective temperature 77- 80 F4.2 [Lsun] logL ?=- Luminosity (L=Teff4/g)
Note (1): Spectral classifications must be handled with caution since they come from various sources, not all of which are equally reliable. Note (2): Relative skewness, RSk=<v3>/(<v2>3/2), where v2 and v3 are the second and third normalized central moments of a spectral line, see Equation (1), Sect. 3.2 of the paper.
History: From electronic version of the journal References: Simon-Diaz et al., Paper I 2014A&A...562A.135S, Cat. J/A+A/562/A135 Simon-Diaz et al., Paper II 2014A&A...570L...6S
(End) Patricia Vannier [CDS] 09-Dec-2016
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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