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J/PASP/121/117 Fe and Ti abundances of 12 low-metallicity M stars (Woolf+, 2009)

Calibrating M-dwarf metallicities using molecular indices: extension to low-metallicity stars. Woolf V.M., Lepine S., Wallerstein G. <Publ. Astron. Soc. Pac., 121, 117-124 (2009)> =2009PASP..121..117W
ADC_Keywords: Stars, dwarfs ; Stars, M-type ; Abundances Abstract: We have calculated Fe and Ti abundances in 12 low-metallicity main sequence M stars using high-resolution spectra. These subdwarf and extreme-subdwarf stars allow us to extend our calibration of a method to determine cool-dwarf-star metallicities using molecular band strength indices from low-resolution spectra. Our calibration can now be used to determine metallicity to within ±0.3dex for stars with [Fe/H] between -1.5 and +0.05 and temperatures between 3500 and 4000K. We also report a method to estimate temperatures for M dwarfs using equivalent width measurements of the infrared CaII triplet and the KI line at 7699Å. Our metallicity measurements show that the recently proposed classification system for low-mass stars (dwarfs, subdwarfs, extreme subdwarfs, and ultrasubdwarfs) does represent a metallicity sequence, with the ultrasubdwarfs the most metal-poor stars. Description: We obtained spectra of 12 subdwarf and extreme-subdwarf M stars using queue scheduled observing of the Hobby-Eberly Telescope. The spectra were measured using the high-resolution spectrograph set to give spectral resolution λ/Δλ∼30,000. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 92 12 M and K dwarf magnitudes and parallaxes table3.dat 49 274 Fe and Ti line data
Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Star name 17- 20 A4 --- --- [LSPM] 22- 31 A10 --- LSPM LSPM designation (JHHMM+DDMM, Cat. I/298) 33- 39 A7 --- SpType Spectral type (4) 41- 46 F6.3 mag Vmag ? V magnitude (1) 48- 52 F5.3 mag e_Vmag ? rms uncertainty on Vmag 54- 59 F6.3 mag Ksmag Ks magnitude (2) 61- 65 F5.3 mag e_Ksmag rms uncertainty on Ksmag 67- 72 F6.3 mag Hmag ? H magnitude (2) 74- 78 F5.3 mag e_Hmag ? rms uncertainty on Hmag 80- 83 F4.1 mas plx ? Parallax 85- 88 F4.2 mas e_plx ? rms uncertainty on plx 90- 92 A3 --- r_plx Reference for plx (3)
Note (1): V photometry from Mermilliod, Mermilliod & Hauck, 1997A&AS..124..349M except LHS 318 from Smart et al. 2007A&A...464..787S Note (2): Ks and H photometry from Cutri et al. (2003, Cat. II/246). Note (3): References as follows: RG = Reid & Gizis (2005, Cat. III/198) Tor = Smart et al. (2007A&A...464..787S) Yal = van Altena et al. (1995, Cat. I/238) Note (4): The spectral type is categorized with 'sd' = subdwarf, 'esd' = extreme subdwarfs and 'usd' = ultra subdwarfs, in order of decreasing apparent metal content.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 15 A15 --- Name Star name 17- 20 A4 --- El Element 22- 28 F7.2 0.1nm lambda Wavelength 30- 33 F4.2 eV chi Excitation potential 35- 40 F6.3 [-] loggf Oscillator strength 42- 44 I3 0.1pm EW Equivalent width 46- 49 F4.2 [-] logN Abundance
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 26-Apr-2009
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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