Access to Astronomical Catalogues

← Click to display the menu
J/ApJ/699/66        Abundances in two Galactic bulge stars        (Cohen+, 2009)

Clues to the metallicity distribution in the Galactic bulge: abundances in MOA-2008-BLG-310S and MOA-2008-BLG-311S. Cohen J.G., Thompson I.B., Sumi T., Bond I., Gould A., Johnson J.A., Huang W., Burley G. <Astrophys. J., 699, 66-75 (2009)> =2009ApJ...699...66C
ADC_Keywords: Abundances ; Equivalent widths ; Gravitational lensing ; Stars, dwarfs Keywords: Galaxy: bulge - gravitational lensing - stars: abundances Abstract: We present abundance analyses based on high dispersion and high signal-to-noise ratio Magellan spectra of two highly microlensed Galactic bulge stars in the region of the main-sequence turnoff with Teff∼5650K. We find that MOA-2008-BLG-310S has [Fe/H]8=+0.41±0.09dex and MOA-2008-BLG-311S has +0.26±0.09dex. The abundance ratios for the ∼20 elements for which features could be detected in the spectra of each of the two stars follow the trends with [Fe/H] found among samples of bulge giants. Combining these two bulge dwarfs with the results from previous abundance analysis of four other Galactic bulge turnoff region stars, all highly magnified by microlensing, gives a mean [Fe/H] of +0.29dex. This implies that there is an inconsistency between the Fe-metallicity distribution of the microlensed bulge dwarfs and that derived by the many previous estimates based on surveys of cool, luminous bulge giants, which have mean [Fe/H]~-0.1dex. Description: MOA-2008-BLG-310S and MOA-2008-BLG-311S were observed on two consecutive nights in 2008 July using the Magellan Inamori Kyocera Echelle (MIKE) spectrograph on the 6.5m Magellan Clay Telescope at the Las Campanas Observatory by I. Thompson and G. Burley. Objects: ------------------------------------------------------------ RA (2000) DE Designation(s) ------------------------------------------------------------ 17 54 14.4 -34 46 38 MOA-2008-BLG-310S = MOA 2008-BLG-310 17 56 53.7 -31 23 40 MOA-2008-BLG-311S = MOA 2008-BLG-311 ------------------------------------------------------------ File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table4.dat 49 682 Wλ for the sample extremely metal-poor (EMP) stars from the Hamburg/ESO Survey (HES)
See also: J/A+A/512/A41 : Abundances of microlensed stars in the Bulge (Bensby+, 2010) J/A+A/499/737 : Abundances of microlensed dwarf and subgiant stars (Bensby+, 2009) J/ApJ/682/1029 : Abundances in OGLE-2007-BLG-349S (Cohen+, 2008) Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 17 A17 --- Name Star designation (MOA-2008-BLG-310S or MOA-2008-BLG-311S) 19- 25 F7.2 0.1nm lambda Wavelength in Angstroms 27- 31 A5 --- Ion Species identification 33- 36 F4.2 eV ExPot Excitation potential 38- 43 F6.3 [-] log(gf) Log of the oscillator strength 45- 49 F5.1 0.1pm EW ? Equivalent width in milli-Angstroms
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 10-Aug-2011
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

catalogue service