Volume 493, Number 1, January I 2009
|Page(s)||L5 - L8|
|Published online||27 November 2008|
Letter to the Editor
Star-forming galaxies in SDSS: signs of metallicity evolution
Instituto de Astrofísica de Canarias, 38200 La Laguna, Spain e-mail: firstname.lastname@example.org
2 Departamento de Astrofísica, Universidad de la Laguna, Spain
3 Herschel Science Center, INSA/ESAC, Madrid, Spain
Accepted: 16 November 2008
Context. Evolution of galaxies through cosmic time has been widely studied at high redshift, but there are a few studies in this field at lower redshifts. However, low-redshifts studies will provide important clues to the evolution of galaxies, furnishing the required link between local and high-redshift universe.
Aims. In this work we focus on the metallicity of the gas in spiral galaxies at low redshift looking for signs of chemical evolution. We analyze the metallicity contents of star forming galaxies of similar luminosities at different redshifts, we studied the metallicity of star forming galaxies from SDSS-DR5 (Sloan Digital Sky Survey-Data Release 5), using different redshift intervals from 0.1 to 0.4.
Methods. We used the public data of SDSS-DR5 processed with the STARLIGHT spectral synthesis code, correcting the fluxes for dust extinction, estimating metallicities using the R23 method, and analyzing the samples with respect to the [N ii] λ6583/[O ii] λ3727 line ratio.
Results. From a final sample of 207 galaxies, we find a decrement in 12+log(O/H) corresponding to the redshift interval 0.3 < z < 0.4 of ~0.1 dex with respect to the rest of the sample, which can be interpreted as evidence of the metallicity evolution in low-z galaxies.
Key words: galaxies: abundances / galaxies: evolution / galaxies: starburst
© ESO, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.