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III/176              RR Lyrae Metallicities             (Layden 1994)

RR Lyrae data II. The Metallicities and Kinematics of Local RR Lyrae Layden A.C. <Astron. J. 110, 2288 (1995)> =1995AJ....110.2288L
ADC_Keywords: Abundances ; Radial velocities ; Stars, variable ; Stars, population II ; Abundances, [Fe/H] Abstract: This catalog presents metal abundance, distance and radial velocity data on a sample of 302 ab-type RR Lyrae variables within about 2.5 kpc of the Sun. The metal abundance information was obtained from low-medium resolution spectra, using the pseudo-equivalent widths of the Ca II K line and the the H-delta, H-gamma and H-beta lines. The technique employed was similar to Preston's (1959ApJ...130..507P) Δ-S method, though significant differences exist; see the source reference for details. The data were calibrated to the Zinn & West (1984ApJS...55...45Z) globular cluster abundance scale. The photometry employed in the distance determinations was primarily taken from the General Catalog of Variable Stars (1985, hereafter GCVS4). Exceptions are noted in column 29; the letters match the footnotes in Table 10 of Layden (1994AJ....108.1016L). The minimum and maximum light photometry, and rise-time were combined following Barnes & Hawley (1986ApJ...307L...9B) to give an estimate of the intensity- averaged magnitude, i.e. the magnitude the star would have if it were not variable. When the GCVS4 quoted magnitudes in passbands other than V, the GCVS4 magnitudes were transformed to the V passband using the relations established in Layden (1994AJ....108.1016L). The interstellar absorption estimates are from Burstein & Heiles (1982AJ.....87.1165B), modified by a simple dust-distribution model. The distances were computed assuming the Mv(RR)-[Fe/H] relation of Carney, Storm & Jones (1992ApJ...386..663C). Radial velocities were measured from the spectra via cross-correlation with secondary velocity standards. The velocities from the individual spectra were fit with a standard radial velocity curve in the (phase, velocity) plane, to give an estimate of the systemic (center of mass) velocity of each star. The error in this value was estimated from the scatter about the best-fit velocity curve, and the quality of the spectra employed. Other methods were used to combine the individual velocities when the situation demanded (cm = 2,3 in column 70; see Layden (1994AJ....108.1016L) for details). The observed velocities were combined with values from the literature to produce a final, best estimate of the systemic radial velocity of each star, and its error. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 79 302 Data for RR Lyrae stars
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Name Variable star name (as in GCVS4) 10- 14 F5.2 [Sun] Fe/H *Metal abundance [Fe/H] 15 A1 --- u_Fe/H Uncertainty flag (:) 17- 20 F4.2 [Sun] e_Fe/H Estimated error in [Fe/H] 22 I1 --- o_Fe/H Number of spectra used for [Fe/H] estimate 24- 28 F5.2 mag mag Intensity-averaged magnitude (B or V) 29 A1 --- r_mag Reference of magnitude (see source reference) 31 A1 --- n_mag [BVpv] band (p=photographic, v=photovisual) 33- 36 F4.2 mag abs *Interstellar absorption in V 38- 41 F4.2 kpc dist Distance from Sun 43- 46 F4.2 kpc e_dist Estimated error in distance 48- 52 F5.2 kpc Zpos Distance from the Galactic plane 54- 58 F5.2 kpc Rpos Distance from the Galactic center 60- 63 I4 km/s RVm Measured systemic radial velocity 65- 66 I2 km/s e_RVm Estimated error in measured radial velocity 67- 68 I2 --- o_RVm Number of spectra used for radial velocity 70 I1 --- n_RVf *[1,3] Radial velocity combination method 72- 75 I4 km/s RVf *Final systemic radial velocity 77- 78 I2 km/s e_RVf Estimated error in final radial velocity 79 A1 --- u_RVf *Measured and published disagreement
Note on Fe/H: On the Zinn & West scale (1984ApJS...55...45Z) Note on abs: From Burstein & Heiles (1982AJ.....87.1165B) Note on RVf: A combination of RVm, and values from the literature Note on u_RVf: A colon indicates the measured and literature velocity estimates disagree by more than the quoted error (e_RVf). The quoted error may be too small. Note on n_RVf: See section 3.13 of paper I(1994AJ....108.1016L): 1 indicates a systemic velocity from fitted radial veolcity curve; 2 indicates that several spectra of the star were used; 3 indicates that only one spectrum was available for that star.
History: * 02-May-1994: Prepared and documented by Nancy G. Roman [NASA/NSSDC/ADC] and A. C. Layden * 18-Oct-2008: standardized this ReadMe file (CDS) References: Barnes, T.G.III & Hawley, S. 1986ApJ...307L...9B Burstein, D. & Heiles, C. 1982AJ.....87.1165B Carney, B.W. Storm, J. & Jones, R.V. 1992ApJ...386..663C Kholopov, P.N. 1985, General Catalog of Variable Stars, 4th Edition, (Moscow: Nauka Publishing House) Preston, G.W. 1959ApJ...130..507P Zinn, R.J. & West, M.J. 1984ApJS...55...45Z
(End) Nancy G. Roman [NASA/NSSDC/ADC] and A.C. Layden 02-May-1994
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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