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J/A+A/440/305   Fundamental parameters of fast-rotating B stars  (Fremat+, 2005)

Effects of gravitational darkening on the determination of fundamental parameters in fast-rotating B-type stars. Fremat Y., Zorec J., Hubert A.-M., Floquet M. <Astron. Astrophys., 440, 305-320 (2005)> =2005A&A...440..305F
ADC_Keywords: Models, atmosphere ; Stars, early-type Keywords: stars: abundances - stars: atmospheres - stars: early-type - stars: emission-line, Be - stars: fundamental parameters Abstract: In this paper we develop a calculation code to account for the effects carried by fast rotation on the observed spectra of early-type stars. Stars are assumed to be in rigid rotation, and the grid of plane-parallel model atmospheres used to represent the gravitational darkening are calculated by means of a non-LTE approach. Attention is paid to the relation between the apparent and parent non-rotating counterpart stellar fundamental parameters and apparent, and true Vsini parameters as a function of the rotation rate Omega/Omegac, stellar mass, and inclination angle. It is shown that omitting of gravitational darkening in the analysis of chemical abundances of CNO elements can produce systematic overestimation or underestimation, depending on the lines used, rotational rate, and inclination angle. Description: The reference model parameters proper to calculating FASTROT rotationally modified synthetic spectra, as well as those obtained by fitting the rotationally distorted spectra with them, are hereafter called parent non-rotating counterpart (pnrc) fundamental parameters, while vsini will represent the true projected rotation velocity of the star. Conversely, we call apparent fundamental parameters (e.g. TeffA, loggA and vsiniA), those derived by fitting the GRIDB spectral lines with synthetic spectra issued from classical plane-parallel model atmospheres. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table9.dat 80 129 Apparent and parent non-rotating counterpart (pnrc) fundamental parameters of the studied stars
Byte-by-byte Description of file: table9.dat
Bytes Format Units Label Explanations
1- 6 I6 --- HD HD number of the star 8- 12 I5 K TeffA Apparent effective temperature 14- 16 I3 K e_TeffA rms uncertainty on TeffA 18- 22 F5.3 [cm/s2] loggA Apparent surface gravity 24- 28 F5.3 [cm/s2] e_loggA rms uncertainty on loggA 30- 32 I3 km/s vsiniA Apparent rotational velocity 34- 35 I2 km/s e_vsiniA rms uncertainty on vsiniA 37- 41 I5 K Teff Effective temperature, pnrc parameter 43- 45 I3 K e_Teff rms uncertainty on Teff 47- 51 F5.3 [cm/s2] logg Surface gravity, pnrc parameter 53- 57 F5.3 [cm/s2] e_logg rms uncertainty on logg 59- 61 I3 km/s vsini Corrected rotational velocity (pnrc) (1) 63- 64 I2 km/s e_vsini rms uncertainty on vsini 66- 68 I3 km/s Vc Critical equatorial velocity (pnrc) (1) 70- 71 I2 km/s e_Vc rms uncertainty on Vc 73- 76 F4.1 deg incl Estimated inclination angle (pnrc) (1) 78- 80 F3.1 deg e_incl rms uncertainty on incl
Note (1): pnrc = parent non-rotating counterpart (see the "Description" section above)
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Jul-2006
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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