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J/A+A/404/689       Metallicities of Slowly Pulsating B stars (Niemczura+, 2003)

Metallicities of the SPB stars from the IUE ultraviolet spectra. Niemczura E. <Astron. Astrophys. 404, 689 (2003)> =2003A&A...404..689N
ADC_Keywords: Stars, early-type ; Stars, B-type ; Abundances ; Spectra, ultraviolet Keywords: stars: early-type - stars: abundances - stars: variables: general Abstract: We derived the stellar parameters (angular diameters, effective temperatures, metallicities) and interstellar reddenings for 20 Slowly Pulsating B (SPB) and 34 reference stars observed during the IUE satellite mission. The parameters were derived by means of an algorithmic procedure of fitting theoretical flux distributions to the low-resolution IUE spectra and optical spectrophotometric observations. Since the metallicity [m/H] has a special importance for pulsating B type stars, we focused our attention on that parameter. We found that the mean value of the metallicity of the considered SPB and reference stars amounts to [m/H]~-0.20. The results only slightly depend on the reduction procedure used for the IUE images (NEWSIPS and INES). The metal abundances obtained in this paper are in accordance with the average value of -0.2dex for stars in the solar neighborhood recently reported by other investigators. Description: The observational material consists of the IUE observations obtained with the large and small apertures from both the long-wavelength (LWP and LWR, 1950-3200Å) and the short-wavelength (SWP, 1100-1950Å) cameras with high (0.1-0.3Å) and low (6-7Å) spectral resolutions. We used observations processed by two reduction packages: the IUE/NEWSIPS (New Spectral Image Processing System,) and IUE/INES (IUE Newly Extracted Spectra) File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file stars.dat 68 54 Star positions and magnitudes (from Simbad) table3.dat 99 40 The best-fit parameters for the SPB stars obtained from IUE/NEWSIPS low resolution data table4.dat 99 40 The best-fit parameters for the SPB stars obtained from IUE/INES low resolution data table5.dat 99 68 The best-fit parameters for the reference stars table6.dat 72 28 The parameters specifying the shape of the UV extinction curves of SPB and reference stars table7.dat 46 55 Mean correlation coefficients. All results were obtained from the IUE/NEWSIPS spectra
See also: VI/99 : Merged Log of IUE Observations (NASA-ESA, 1999) Byte-by-byte Description of file: stars.dat
Bytes Format Units Label Explanations
1- 2 A2 --- --- [HD] 4- 9 I6 --- HD HD number 13- 14 I2 h RAh Right ascension (J2000.0) 16- 17 I2 min RAm Right ascension (J2000.0) 19- 22 F4.1 s RAs Right ascension (J2000.0) 24 A1 --- DE- Declination sign (J2000.0) 25- 26 I2 deg DEd Declination (J2000.0) 28- 29 I2 arcmin DEm Declination (J2000.0) 31- 32 I2 arcsec DEs Declination (J2000.0) 36- 40 F5.2 mag Bmag ? B magnitude 42- 46 F5.2 mag Vmag ? V magnitude 48- 68 A21 --- SpType Spectral type
Byte-by-byte Description of file: table3.dat table4.dat table5.dat
Bytes Format Units Label Explanations
1- 6 I6 --- HD HD number of the star 8 A1 --- Data [bmni] Type of data (1) 10- 14 F5.3 K logTeff Effective temperature 17- 21 F5.3 K e_logTeff The Error of the effective temperature 24- 27 F4.2 --- logg Gravity 30- 34 F5.2 Sun [m/H] The Metallicity 37- 40 F4.2 --- e_[m/H] The Error of the metallicity 43- 47 F5.3 mas theta Stellar diameter 50- 54 F5.3 mas e_theta The error of the stellar diameter 57- 61 F5.3 mag E(B-V) Interstellar extinction 64- 68 F5.3 mag e_E(B-V) The error of the interstellar extinction 71- 76 F6.3 --- S1 The S1 parameter (2) 79- 83 F5.3 --- e_S1 The error of the S1 parameter 86- 91 F6.3 --- S2 The S2 parameter (2) 94- 98 F5.3 --- e_S2 The error of the S2 parameter
Note (1): Type of data: b: best-fit parameters together with the formal errors m: median values from the bootstrap resampling of each parameter together with 1σ uncertainties n: parameters obtained from IUE/NEWSIPS low resolution data i: parameters obtained from IUE/INES low resolution data Note (2): The parameters S1 and S2 adjust the short- and long-wavelength parts of IUE spectra to the visual flux level (F*S1*S2). Outside the IUE/SWP region we put S1=1, whereas S2=1 is set outside the wavelength region covered by the long-wavelength IUE observations.
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 6 A6 --- HD HD number of the star 8- 9 A2 --- Data [brn iue] Type of data (1) 11- 14 F4.2 --- gamma Width, gamma (mean = 0.99) (2) 17- 20 F4.2 --- e_gamma The error of gamma 23- 27 F5.3 --- x0 Position, x0 (mean = 4.596) (2) 30- 34 F5.3 --- e_x0 The error of x0 37- 41 F5.3 --- c2 Linear term, c2 (mean = 0.698) (2) 44- 48 F5.3 --- e_c2 The error of c2 51- 54 F4.2 --- c3 Strenth, c3 (mean = 3.23) (2) 57- 60 F4.2 --- e_c3 The error of c3 63- 66 F4.2 --- c4 Far-UV curvature term, c4 (mean = 0.41) (2) 69- 72 F4.2 --- e_c4 The error of c4
Note (1): Type of data: bn: best-fit resampling results for IUE/NEWSIPS spectra rn: bootstrap resampling results for IUE/NEWSIPS spectra iu: results for IUE observations in: results for INES observations n: best-fit solutions for IUE/NEWSIPS data for reference stars i: best-fit solutions for IUE/INES data for reference stars Note (2): The parameters of the mean extinction curve (Fitzpatrick, 1999PASP..111...63F) are given for comparison.
Byte-by-byte Description of file: table7.dat
Bytes Format Units Label Explanations
1- 6 A6 --- P1 The first parameter designation (1) 8- 15 A8 --- P2 The second parameter designation (1) 17- 20 F4.2 --- rhoMean Mean correlation coefficients 23- 26 F4.2 --- sigmarho Standard deviations 29- 32 F4.2 --- rhoMedian Median values of correlations 35- 38 F4.2 --- rhoMedianMax The largest values of rhoMedian 41- 44 F4.2 --- rhoMedianMin The lowest values of rhoMedian
Note (1): Correlations between the E(B-V), S1, Teff, [m/H], c2, c3, c4, gamma, theta and x0 parameters
Acknowledgements: Ewa Niemczura
(End) Patricia Bauer [CDS] 06-Jun-2003
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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