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J/ApJ/602/200  HII regions abundances in blue compact galaxies (Izotov+, 2004)

Systematic effects and a new determination of the primordial abundance of 4He and dY/dZ from observations of blue compact galaxies. Izotov Y.I., Thuan T.X. <Astrophys. J., 602, 200-230 (2004)> =2004ApJ...602..200I
ADC_Keywords: Galaxies, spectra ; H II regions ; Abundances Keywords: galaxies: abundances - galaxies: irregular - galaxies: ISM - H II regions - ISM: abundances Abstract: We use spectroscopic observations of a sample of 82 HII regions in 76 blue compact galaxies to determine the primordial helium abundance Yp and the slope dY/dZ from the Y-O/H linear regression. To improve the accuracy of the dY/dZ measurement, we have included new spectrophotometric observations of 33 HII regions that span a large metallicity range, with oxygen abundance 12+log(O/H) varying between 7.43 and 8.30 (Z/30≤Z≤Z/4). Most of the new galaxies were selected from the First Byurakan, the Hamburg/SAO, and the University of Michigan objective prism surveys. Description: We have obtained new high signal-to-noise ratio spectrophotometric observations for 33 HII regions in 31 BCGs with the Kitt Peak 4m telescope on the nights of 2002 December 30-31 and 2003 January 1. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 84 31 General parameters of galaxies refs.dat 71 27 References table3.dat 89 1389 HII regions emission line intensities and equivalent widths table4.dat 57 1221 HII regions ionic and total heavy element and helium abundances table5.dat 57 89 Sample used for primordial helium abundance determination
See also: J/AZh/79/867 : Abundances of HII regions in blue galaxies (Holovatyy+, 2002) J/ApJ/511/639 : Abundances in blue compact galaxies (Izotov+, 1999) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 13 A13 --- Name Galaxy name (1) 15- 16 I2 h RAh Right ascension (J2000.0) 18- 19 I2 min RAm Right ascension (J2000.0) 21- 24 F4.1 s RAs Right ascension (J2000.0) 26 A1 --- DE- Declination sign (J2000.0) 27- 28 I2 deg DEd Declination (J2000.0) 30- 31 I2 arcmin DEm Declination (J2000.0) 33- 34 I2 arcsec DEs Declination (J2000.0) 36- 39 F4.1 mag pgmag ? Photographic magnitude 41- 47 F7.5 --- z Redshfit, derived from spectra in this paper 49- 55 F7.5 --- e_z rms uncertainty on z 57- 61 F5.1 mag PGMAG ? Absolute photographic magnitude (2) 63- 78 A16 --- OName Other names 80- 84 A5 --- r_Name References, in refs.dat file
Note (1): CGCG 007-025 = Z 7-25 in Simbad Note (2): All objects are assumed to be at their redshift distances with H0=75km/s/Mpc.
Byte-by-byte Description of file: refs.dat
Bytes Format Units Label Explanations
1- 2 I2 --- Ref Reference number 4- 22 A19 --- BibCode BibCode 24- 50 A27 --- Aut Author's name 51- 71 A21 --- Com Comments
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 13 A13 --- Name Galaxy name 15 I1 --- n_Name [1/2]? Number of the HII region when two different HII regions were extracted. 17- 20 I4 0.1nm Lambda Wavelength 22- 35 A14 --- Ion Ion species 37- 41 F5.3 ---- Hbec Hβ extinction coefficient 43- 51 E9.3 mW/m2 FHbeta Uncorrected Hβ line flux in erg/cm2/s 53- 56 F4.2 0.1nm EWHbeta Hβ absorption line equivalent width 58- 63 F6.2 --- Flux ? Observed flux relative to Hβ 65- 69 F5.2 --- e_Flux ? Error in Flux 71- 76 F6.2 --- Fluxc ? corrected flux relative to Hbeta (1) 78- 82 F5.2 --- e_Fluxc ? Error in Fluxc 84- 89 F6.1 0.1nm EW ? Equivalent width in Angstroms
Note (1): Corrected for both reddening Whitford (1958AJ.....63..201W) and underlying hydrogen stellar absorption.
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 13 A13 --- Name Galaxy name 15 I1 --- n_Name [1/2]? Number of the HII region when two 17- 37 A21 --- Prop Property and units 39- 48 F10.4 --- Value ? Value of the property 50- 57 F8.4 --- e_Value ? Error in Value
Byte-by-byte Description of file: table5.dat
Bytes Format Units Label Explanations
1- 13 A13 --- Name Galaxy name 15 A1 --- n_Name [1/2]? Number of the HII region when two different HII regions were extracted 17- 21 F5.2 10+4 O/H O/H abundance 23- 26 F4.2 10+4 e_O/H rms uncertainty on O/H 28- 33 F6.2 10+6 N/H N/H abundance 35- 39 F5.2 10+6 e_N/H rms uncertainty on N/H 42- 47 F6.4 --- Y Y abundance 49- 54 F6.4 --- e_Y rms uncertainty on Y 56- 57 I2 --- r_O/H References, in refs.dat file
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 06-Apr-2004
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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