The Great Observatories Origins Deep Survey. VLT/FORS2 Spectroscopy in the GOODS-South Field: Part III

TL;DR

This paper presents a comprehensive spectroscopic dataset from the ESO/GOODS program in the GOODS-South field, including redshift measurements for over 800 galaxies, enhancing the understanding of galaxy distribution at various cosmic epochs.

Contribution

It provides a large, high-quality spectroscopic catalog with redshifts for over 800 galaxies, utilizing VLT/FORS2 observations, and compares results with existing data to validate redshift accuracy.

Findings

Redshift distribution spans z=0.5 to 2 and z=3.5 to 6.3.

Achieved redshift measurement uncertainty of sigma(z) ~ 0.001.

Spectroscopic data and redshifts are publicly released for community use.

Abstract

Aims. We present the full data set of the spectroscopic campaign of the ESO/GOODS program in the GOODS-South field, obtained with the FORS2 spectrograph at the ESO/VLT. Method. Objects were selected as candidates for VLT/FORS2 observations primarily based on the expectation that the detection and measurement of their spectral features would benefit from the high throughput and spectral resolution of FORS2. The reliability of the redshift estimates is assessed using the redshift-magnitude and color-redshift diagrams, and comparing the results with public data. Results. Including the third part of the spectroscopic campaign (12 masks) to the previous work (26 masks, Vanzella et al. 2005, 2006), 1715 spectra of 1225 individual targets have been analyzed. The actual spectroscopic catalog provides 887 redshift determinations. The typical redshift uncertainty is estimated to be sigma(z) ~ 0.001. Galaxies have been selected adopting different color criteria and using photometric redshifts. The resulting redshift distribution typically spans two domains: from z=0.5 to 2 and z=3.5 to 6.3. The reduced spectra and the derived redshifts are released to the community through the ESO web page http://www.eso.org/science/goods/