Artículos de revistas
Photometric redshifts and K-corrections for the Sloan Digital Sky Survey Data Release 7
Fecha
2011-05Registro en:
O'Mill, Ana Laura; Duplancic Videla, Maria Fernanda; Garcia Lambas, Diego Rodolfo; Sodré Junior, Laerte; Photometric redshifts and K-corrections for the Sloan Digital Sky Survey Data Release 7; Oxford University Press; Monthly Notices Of The Royal Astronomical Society; 413; 2; 5-2011; 1395-1408
0035-8711
Autor
O'Mill, Ana Laura
Duplancic Videla, Maria Fernanda
Garcia Lambas, Diego Rodolfo
Sodré Junior, Laerte
Resumen
We present a catalogue of galaxy photometric redshifts and k-corrections for the Sloan Digital Sky Survey Data Release 7 (SDSS-DR7), available on the World Wide Web. The photometric redshifts were estimated with an artificial neural network using five ugriz bands, concentration indices and Petrosian radii in the g and r bands. We have explored our redshift estimates with different training sets, thus concluding that the best choice for improving redshift accuracy comprises the main galaxy sample (MGS), the luminous red galaxies and the galaxies of active galactic nuclei covering the redshift range 0 < z≤ 0.3. For the MGS, the photometric redshift estimates agree with the spectroscopic values within rms = 0.0227. The distribution of photometric redshifts derived in the range 0 < zphot≤ 0.6 agrees well with the model predictions.
k-corrections were derived by calibration of the k-correct_v4.2 code results for the MGS with the reference-frame (z= 0.1) (g−r) colours. We adopt a linear dependence of k-corrections on redshift and (g−r) colours that provide suitable distributions of luminosity and colours for galaxies up to redshift zphot= 0.6 comparable to the results in the literature. Thus, our k-correction estimate procedure is a powerful, low computational time algorithm capable of reproducing suitable results that can be used for testing galaxy properties at intermediate redshifts using the large SDSS data base.