ECDFSOID ivo://nasa.heasarc/ecdfsoid NASA/GSFC HEASARC Treister et al. 2026-10-09 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains the first results of the authors' optical spectroscopy program aimed to provide redshifts and identifications for the X-ray sources in the Extended Chandra Deep Field South (ECDFS). A total of 339 sources (listed herein) were targeted using the IMACS spectrograph at the Magellan telescopes and the VIMOS spectrograph at the VLT. The authors have measured redshifts for 186 X-ray sources, including archival data and a literature search. They find that the active galactic nucleus (AGN) host galaxies have on average redder rest-frame optical colors than nonactive galaxies, and that they live mostly in the "green valley." The dependence of the fraction of AGNs that are obscured on both luminosity and redshift is confirmed at high significance and the observed AGN spatial density is compared with the expectations from existing luminosity functions. These AGNs show a significant difference in the mid-IR to X-ray flux ratio for obscured and unobscured AGNs, which can be explained by the effects of dust self-absorption on the former. This difference is larger for lower luminosity sources, which is consistent with the dust opening angle depending on AGN luminosity. This table was created by the HEASARC in April 2009 based on the electronic version of Table 2 from the Treister et al. (2009) paper obtained from the ApJ web site, except for the source positions which were taken from Virani et al. (2006). The full table from the latter paper is also available in Browse (the ECDFSCXO table). This is a service provided by NASA HEASARC . 2009ApJ...693.1713T https://heasarc.gsfc.nasa.gov/W3Browse/all/ecdfsoid.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=ecdfsoid& GET text/xml 180 99999 true 53.13454167 -28.05783333 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=ecdfsoid GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_ecdfsoid&Action=More+Options&Action=Parameter+Search&ConeAdd=1 CHANDRA 0.0166666666666667 Infrared Optical X-ray public ecdfsoid Extended Chandra Deep Field-South Survey Optical Identifications name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable hb_flux Hard X-ray (2-8 keV) Flux erg/s/cm^2 phot.flux;em.X-ray.hard double nullable log_hb_lx Logarithm of Hard X-ray Luminosity log(erg/s) phys.luminosity;em.X-ray.medium double nullable redshift Redshift src.redshift double nullable flux_24_um 24-micron Flux Density mJy phot.flux.density;em.IR.15-30um double nullable flux_24_um_error Error in 24-micron Flux Density mJy stat.error;phot.flux.density;em.IR.15-30um double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable bii Galactic Latitude degree pos.galactic.lat double nullable class Browse Object Classification src.class short nullable spectral_index_neg_err Lower Error in Gamma stat.error;spect.index;em.X-ray double nullable spectrum_source Source of Spectrum meta.code char nullable hardness_ratio Hardness Ratio phot.flux;arith.ratio;em.X-ray double nullable sb_flux Soft X-ray (0.5-2 keV) Flux erg/s/cm^2 phot.flux;em.X-ray.soft double nullable broad_type Optical Classification src.class char nullable hardness_ratio_neg_err Lower Error in Hardness Ratio stat.error;phot.flux;arith.ratio;em.X-ray double nullable source_number Sequential Identification Number for Each Source in Catalog meta.id;src short nullable spectral_index_pos_err Upper Error in Gamma stat.error;spect.index;em.X-ray double nullable spectral_index Gamma Spectral Index spect.index;em.X-ray double nullable ref_flux_24_um Source of 24-micron Photometry meta.ref;phot.flux.density;em.IR.15-30um char nullable hardness_ratio_pos_err Upper Error in Hardness Ratio stat.error;phot.flux;arith.ratio;em.X-ray double nullable log_nh Logarithm of Neutral Hydrogen Column Density log(cm^-2) phys.columnDensity double nullable lii Galactic Longitude degree pos.galactic.lon double nullable