UDF ivo://nasa.heasarc/hubbleudf NASA/GSFC HEASARC Beckwith et al. 2026-10-02 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The Hubble Ultra Deep Field (UDF, Principle Investigator: Steven V. W. Beckwith) is a 400-orbit Hubble Space Telescope (HST) Cycle 12 program to image a single field of the Wide Field Camera (WFC) of the Advanced Camera for Surveys (ACS) in four filters: F435W (B), F606W (V), F775W (i), and F850LP (z). The observations took place over 4 months from September 2003 to January 2004 under two program IDs: 9978 and 10086. The observations consist of half-orbit exposures, cycling through each of the filters in a 4-point dither pattern to provide sub-pixel sampling, as well as a larger-scale 3-point line pattern to cover the 2 second of arc gap between the two ACS/WFC chips. The total exposure times are summarized below, with typical exposure times of 1200s for individual images. The AB magnitude zero-points for ACS are current as of March 2004. <pre> Number of Number of Total Exp. AB mag. Orbits Exposures Time (s) zero-point B (F435W): 56 112 134880 25.673 V (F606W): 56 112 135320 26.486 i (F775W): 144 288 347110 25.654 z (F850LP): 144 288 346620 24.862 </pre> This HEASARC Browse table contains the list of sources found in the deepest UDF image, the i-band image. The formal i-band catalog contains a total of 10,040 sources. A visual inspection of all the sources revealed an additional 5 spurious sources (which do not form part of the catalog). Moreover, the deblending algorithms in SExtractor caused an additional 100 sources to be missed, owing to their proximity to brighter sources. These sources were identified manually, and formally added by doing another SExtractor run with considerably different deblending parameters, in order to detect them all. An initial list of 208 sources was produced, which was then reduced to a total of 100 sources after visual inspection and rejection of sources that were clearly part of previously identified sources. These additional sources are denoted by ID numbers 20001 - 20208. Although the i-band image is the deepest image, there remain additional sources that were not detected in i-band, even though they may be detected in one of the other bands. Therefore, the authors produced a second catalog based on detection in the z-band image (not part of the present table), and an additional 39 sources are included from this catalog that were detected at > 10 sigma in the z-band image, but were not in the catalog that was run using the i-band image for detection. These additional sources are denoted by ID numbers above 30000. More details are found in the file <a href="https://cdsarc.cds.unistra.fr/ftp/cats/II/258/intro.txt">https://cdsarc.cds.unistra.fr/ftp/cats/II/258/intro.txt</a> or from the UDF home page at <a href="http://www.stsci.edu/hst/udf/">http://www.stsci.edu/hst/udf/</a>. This table was created by the HEASARC in May 2005 based on CDS table II/258/udf-i.dat. This is a service provided by NASA HEASARC . https://heasarc.gsfc.nasa.gov/W3Browse/all/hubbleudf.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=hubbleudf& GET text/xml 180 99999 true 53.1644935 -27.82929 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=hubbleudf GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_hubbleudf&Action=More+Options&Action=Parameter+Search&ConeAdd=1 HST 0.0166666666666667 Optical public hubbleudf Hubble Ultra Deep Field Catalog 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 vmag AB Magnitude in F606W Filter Isophotally Matched mag phot.mag;em.opt.V double nullable vmag_error Formal Error on Vmag mag stat.error;phot.mag;em.opt.V double nullable imag AB Magnitude in F775W Filter Isophotally Matched mag phot.mag;em.opt.I double nullable imag_error Formal Error on imag mag stat.error;phot.mag;em.opt.I double nullable stellarity Stellarity (1 for Point Sources, 0 for Fully Resolved Sources) 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 half_light_radius Half-light Radius (pixels) pixel phys.angSize;src double nullable zmag_snr Signal-to-Noise Ratio in F850LP Filter stat.snr;phot.mag;em.opt.I double nullable vmag_snr Signal-to-Noise Ratio in F606W Filter stat.snr;phot.mag;em.opt.V float nullable y_pos Position of the Source (Toward North) pixel pos.cartesian.y;instr.det double nullable bmag_error Formal Error on Bmag mag stat.error;phot.mag;em.opt.B double nullable gaussian_fwhm FWHM of a Gaussian Fit to Each Source pixel phys.angSize double nullable x_pos Position of the Source (Toward East) pixel pos.cartesian.x;instr.det double nullable orientation Source Orientation (Theta), Counterclockwise from X-Axis = PA-90 degree pos.posAng double nullable sextractor_flags SExtractor Flags meta.code short nullable bii Galactic Latitude degree pos.galactic.lat double nullable bmag_snr Signal-to-Noise Ratio in F435W Filter stat.snr;phot.mag;em.opt.B double nullable imag_snr Signal-to-Noise Ratio in F775W Filter stat.snr;phot.mag;em.opt.I double nullable bmag AB Magnitude in F435W Filter Isophotally Matched mag phot.mag;em.opt.B double nullable ellipticity Ellipticity (1-b/a) src.ellipticity double nullable zmag_error Formal Error on zmag mag stat.error;phot.mag;em.opt.I double nullable lii Galactic Longitude degree pos.galactic.lon double nullable zmag AB Magnitude in F850LP Filter Isophotally Matched mag phot.mag;em.opt.I double nullable