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تسجيل مستخدم جديدDirect determination of oxygen abundances in line emitting star-forming galaxies at intermediate redshift
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تأليف
Jose M. Perez
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We present a sample of 22 blue ($(B-V)_{AB}<0.45$), luminous ($M_{B,AB}<-18.9$), metal-poor galaxies in the $0.69<z<0.88$ redshift range, selected from the DEEP2 galaxy redshift survey. Their spectra contain the $[OIII]lambda4363$ auroral line, the $[OII]lambda lambda3726,3729$ doublet and the strong nebular $[OIII]lambda lambda 4959,5007$ emission lines. The ionised gas-phase oxygen abundances of these galaxies lie between $7.62<12+log O/H < 8.19$, i.e. between $1/10 Z_{odot}$ and $1/3 Z_{odot}$. We find that galaxies in our sample have comparable metallicities to other intermediate-redshift samples, but are more metal poor than local systems of similar B-band luminosities and star formation activity. The galaxies here show similar properties to the green peas discovered at $zsimeq 0.2 - 0.3$ though our galaxies tend to be slightly less luminous.
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