J/AJ/116/2081 Hubble Deep Field catalog of color-based redshift (Wang+, 1998)
A catalog of color-based redshift estimates for z≲4 galaxies in the
Hubble Deep Field.
Wang Y., Bahcall N., Turner E.L.
<Astron. J. 116, 2081 (1998)>
=1998AJ....116.2081W 1998AJ....116.2081W (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Redshifts ; Photometry, UBVRI
Mission_Name: HST
Keywords: galaxies: distances and redshifts - methods: data analysis
Abstract:
We derive simple empirical color-redshift relations for z≲4 galaxies
in the Hubble Deep Field (HDF) using a linear function of three
photometric colors (U-B, B-V, V-I). The dispersion between the
estimated redshifts and the spectroscopically observed ones is small
for relations derived in several separate color regimes; the
dispersions range from σz~=0.03 to 0.1 for z≲2 galaxies, and
from σz~=0.14 to 0.25 for z≳2 galaxies. We apply the
color-redshift relations to the HDF photometric catalog and obtain
estimated redshifts that are consistent with those derived from
spectral template fitting methods. The advantage of these
color-redshift relations is that they are simple and easy to use and
do not depend on the assumption of any particular spectral templates;
they provide model independent redshift estimates for z≲4 galaxies
using only multiband photometry, and they apply to about 90% of all
galaxies. We provide a color-based estimated redshift catalog of HDF
galaxies to z≲4. We use the estimated redshifts to investigate the
redshift distribution of galaxies in the HDF; we find peaks in the
redshift distribution that suggest large-scale clustering of galaxies
to at least z∼1 and that are consistent with those identified in
spectroscopic probes of the HDF.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 66 848 Catalog of color-based redshift estimates
--------------------------------------------------------------------------------
See also:
J/A+AS/129/583 : Hubble Deep Field surface photometry (Fasano+ 1998)
J/AJ/112/1335 : Hubble Deep Field observations (Williams+ 1996)
J/AJ/112/359 : Galaxies in the Hubble Deep Field (van den Bergh+ 1996)
J/ApJ/471/L5 : Redshift clustering in the Hubble Deep Field (Cohen+ 1996)
Table 1: galaxies not used in determining the za relations
---------------------------------------------------------------
Sawicki x y z za ztemp
---------------------------------------------------------------
20288 1831.00 753.00 0.609 0.9100 0.65
20456 527.00 1096.00 0.390 0.9474 1.10
30096 716.91 451.61 0.089 0.2757 2.00
30111 1463.00 489.00 1.315 0.9444 1.05
30251 1040.70 774.70 0.642 0.8456 0.70
30802 1618.80 1926.50 0.472 0.7770 0.85
40224 1961.00 599.00 0.961 0.7631 0.95
40818 1002.50 1771.70 0.882 1.5494 2.25
---------------------------------------------------------------
Sawicki: From Sawicki et al. (1997AJ....113....1S 1997AJ....113....1S)catalog,
1st number is chip number
x, y: pixel position on v.2 HDF images
z: spectroscopic redshift
za: color-based redshift
ztemp: redshift from spectral template-fitting
---------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Sawicki Identification number in Sawicki et al.
(1997AJ....113....1S 1997AJ....113....1S) photometric catalog (1)
7- 13 F7.2 pix xpos x position on v2 HDF image
15- 21 F7.2 pix ypos y position on v2 HDF image
23- 27 F5.2 mag m814 m814 (I) magnitude
29- 33 F5.2 mag m606 m606 (V) magnitude
35- 39 F5.2 mag m450 m450 (B) magnitude
41- 45 F5.2 mag m300 m300 (U) magnitude
47- 50 F4.2 --- ztemp Photometric redshift from fitting spectral
templates by Sawicki et al. (1997AJ....113....1S 1997AJ....113....1S)
52- 56 F5.2 --- za Color-based analytic redshift
57 A1 --- Note [*] Note (2)
59 I1 --- cr Color range
61- 65 F5.3 --- z ? Spectroscopic redshift
66 A1 --- u_z [?] Uncertainty flag on z (3)
--------------------------------------------------------------------------------
Note (1): First digit is chip number
Note (2): * indicates the 83 galaxies for which |za-ztemp|> 0.5; 4 of these
have spectroscopic redshifts z, and |za-z| is much smaller than
|ztemp-z|; about half of the 83 galaxies lie close to the border
of |za-ztemp|≤0.5.
Note (3): ? indicates the three galaxies for which the reported spectroscopic
redshifts are erroneous or very uncertain.
--------------------------------------------------------------------------------
History: Copied at ftp://astro.princeton.edu/elt/:HDF
(End) James Marcout, Patricia Bauer [CDS] 19-Jan-1999