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Gas-phase metallicity of 27 galaxies at intermediate redshift

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 نشر من قبل Lorenzo Morelli Dr.
 تاريخ النشر 2012
  مجال البحث فيزياء
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The purpose of this work is to make available new gas-phase oxygen abundance measurements for a serendipitous sample of 27 galaxies with redshift 0.35<z<0.52. We measured the equivalent widths of the [O II]{lambda}3727, H{beta}, and [O III]{lambda}{lambda}4959, 5007 emission lines observed in the galaxy spectra obtained with the Visible Multi-Object Spectrograph mounted at the Very Large Telescope. For each galaxy, we derived the metallicity-sensitive emission lines ratio R23, ionization-sensitive emission lines ratio O32, and gas-phase oxygen abundance 12+log(O/H). The values of gas-phase oxygen abundance 12+log(O/H) we obtained for the sample galaxies are consistent with previous findings for galaxies at intermediate redshift.



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