Journal ArticleDOI
On the Compared Accuracy and Reliability of Spectroscopic and Photometric Redshift Measurements
Alberto Fernández-Soto,Kenneth M. Lanzetta,Hsiao-Wen Chen,Sebastian M. Pascarelle,Noriaki Yahata +4 more
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TLDR
In this article, a comparison between the catalog of spectroscopic redshifts in the Hubble Deep Field (HDF) recently published by Cohen and collaborators and the redshift that our group has measured for the same objects using photometric techniques is performed in order to fully characterize the errors associated with the photometric redshift technique.Abstract:
We present a comparison between the catalog of spectroscopic redshifts in the Hubble Deep Field (HDF) recently published by Cohen and collaborators and the redshifts that our group has measured for the same objects using photometric techniques. This comparison is performed in order to fully characterize the errors associated with the photometric redshift technique. The compilation of spectroscopic redshifts incorporates previously published results, corrections to previously published wrong values, and new data, and it includes over 140 objects in the HDF proper. It represents the deepest, cleanest, most complete spectroscopic catalog ever compiled. We particularly study each and every object for which our redshift and the one measured by Cohen and collaborators seem to disagree. In most of those cases, the photometric evidence we put forth is strong enough to call for a careful review of the spectroscopic values, since the spectroscopic values seem to be in error. We show that it is possible to characterize the systematic errors associated with our technique, which when combined with the well-measured photometric errors allow us to obtain complete information on the redshift of each galaxy and its associated confidence interval, regardless of its apparent magnitude. One of the main conclusions of this study is that, to date, all the redshifts from our published catalog that have been checked have been shown to be correct (within the stated confidence limits). This implies that our set of spectrophotometric galaxy templates is a fair representation of the galaxy population at all redshifts (0 < z < 6) and magnitudes (R < 24) explored thus far. On the other hand, spectroscopy of faint sources is subject to unknown and uncharacterized systematic errors. These errors will in turn be transmitted to any photometric redshift technique that uses spectroscopic samples in its calibration. Our analysis proves that photometric redshift techniques can and must be used to extend the range of applicability (in redshift, signal-to-noise, and apparent magnitude) of the spectroscopic redshift measurements.read more
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Journal ArticleDOI
SWIRE: The SIRTF Wide‐Area Infrared Extragalactic Survey
Carol J. Lonsdale,Harding E. Smith,M. Rowan-Robinson,Jason Surace,David L. Shupe,Cong Xu,Sebastian Oliver,Deborah L. Padgett,Fan Fang,Tim Conrow,Alberto Franceschini,Nick Gautier,Matthew Joseph Griffin,Perry B. Hacking,Frank J. Masci,Glenn Morrison,J. O'Linger,Frazer N. Owen,Ismael Perez-Fournon,Marguerite Pierre,R. C. Puetter,Gordon J. Stacey,Sandra Castro,Maria del Carmen Polletta,Duncan Farrah,Thomas H. Jarrett,Dave Frayer,Brian Siana,Tom Babbedge,Simon Dye,M. Fox,Eduardo Gonzalez-Solares,Malcolm Salaman,Stefano Berta,James J. Condon,Herve Dole,Steve Serjeant +36 more
TL;DR: The SIRTF Wide Area Infrared Extragalactic Survey (SWIRE) as discussed by the authors is a legacy program of the International Astronomical Union (IAU) that has been used to trace the evolution of galaxies, star forming and active galactic nuclei.
Journal ArticleDOI
The Stellar Populations and Evolution of Lyman Break Galaxies
TL;DR: In this paper, the spectral energy distributions (SEDs) of Lyman break galaxies (LBGs) at 2.0 z 3.5 were examined using deep near-infrared and optical observations of the Hubble Deep Field-North from the Hubble Space Telescope NICMOS and WFPC2 instruments and from the ground.
Journal ArticleDOI
The Evolution of the global stellar mass density at 0 < z < 3
Mark Dickinson,Mark Dickinson,Casey Papovich,Casey Papovich,Henry C. Ferguson,Tamás Budavári +5 more
TL;DR: In this paper, the authors measured rest-frame optical light and calculations of stellar mass at high redshift based on an infrared-selected sample of galaxies from the Hubble Deep Field-North.
Journal ArticleDOI
Galaxies in the Hubble Ultra Deep Field. I. Detection, Multiband Photometry, Photometric Redshifts, and Morphology
Dan Coe,Dan Coe,Narciso Benítez,Narciso Benítez,Sebastián F. Sánchez,Myungkook J. Jee,Rychard Bouwens,Holland C. Ford +7 more
TL;DR: In this article, the authors presented aperture-matched point-spread function (PSF)-corrected BVi'z'JH photometry and Bayesian photometric redshifts (BPZ) for objects detected in the Hubble Ultra Deep Field (UDF), 8042 of which are detected at the 10 σ level (e.g., i' < 29.01 or z' < 28.43).
Journal ArticleDOI
UV star-formation rates of GRB host galaxies
TL;DR: In this article, a magnitude-limited sample of 10 gamma-ray burst (GRB) host galaxies with known spectroscopic red-shift (0.43 < z < 2.04) was used to derive photometric redshifts, galaxy types, ages of the dominant stellar populations, internal extinctions, and ultraviolet (UV) star-formation rates (SFRs) of the host galaxies.
References
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Journal ArticleDOI
Bayesian Photometric Redshift Estimation
TL;DR: In this article, the authors proposed a Bayesian method for estimating the photometric redshift of a galaxy using prior probabilities and Bayesian marginalization, which is shown to be significantly more reliable than those obtained with maximum-likelihood techniques.
Journal ArticleDOI
The Hubble Deep Field: Observations, data reduction, and galaxy photometry
Robert Williams,Brett S. Blacker,Mark Dickinson,W. Van Dyke Dixon,W. Van Dyke Dixon,Henry C. Ferguson,Andrew S. Fruchter,Mauro Giavalisco,Mauro Giavalisco,Ronald L. Gilliland,Inge Heyer,Rocio Katsanis,Zolt Levay,Ray A. Lucas,Douglas B. McElroy,Douglas B. McElroy,Larry Petro,Marc Postman,Hans Martin Adorf,Richard Hook +19 more
TL;DR: The Hubble Deep Field (HDF) is a Director's Discretionary program on HST in Cycle 5 to image an undistinguished field at high Galactic latitude in four passbands as deeply as reasonably possible as discussed by the authors.
Journal ArticleDOI
The Hubble Deep Field: Observations, Data Reduction, and Galaxy Photometry
Robert Williams,Hdf team +1 more
TL;DR: The Hubble Deep Field (HDF) is a Director's Discretionary program on HST in Cycle 5 to image an undistinguished field at high Galactic latitude in four passbands as deeply as reasonably possible.
Journal ArticleDOI
Spectroscopy of Lyman Break Galaxies in the Hubble Deep Field
TL;DR: In this paper, the spectral discontinuities between the F450W and F300W passbands of galaxies in the Hubble Deep Field were detected, indicating the presence of the Lyman continuum break in the redshift range.
Journal ArticleDOI
Keck Spectroscopy of Redshift z ~ 3 Galaxies in the Hubble Deep Field
James D. Lowenthal,David C. Koo,Rafael Guzman,Jesús Gallego,Andrew C. Phillips,S. M. Faber,Nicole P. Vogt,Garth D. Illingworth,Caryl Gronwall +8 more
TL;DR: In this article, the authors obtained spectra with the 10 m Keck telescope of a sample of 24 galaxies having colors consistent with star-forming galaxies at redshifts 2 z 4.5 in the Hubble deep field (HDF).