J/ApJS/172/615 GALFIT result for GEMS galaxies (Haussler+, 2007)
GEMS: galaxy fitting catalogs and testing parametric galaxy fitting codes:
GALFIT and GIM2D.
Haussler B., McIntosh D.H., Barden M., Bell E.F., Rix H.-W., Borch A.,
Beckwith S.V.W., Caldwell J.A.R., Heymans C., Jahnke K., Jogee S.,
Koposov S.E., Meisenheimer K., Sanchez S.F., Somerville R.S., Wisotzki L.,
Wolf C.
<Astrophys. J. Suppl. Ser., 172, 615-633 (2007)>
=2007ApJS..172..615H 2007ApJS..172..615H
ADC_Keywords: Models ; Morphology ; Galaxy catalogs
Keywords: catalogs - galaxies: general - galaxies: photometry
galaxies: statistics - methods: data analysis - surveys
Abstract:
In the context of measuring the structures of intermediate-redshift
galaxies with HST ACS surveys, we tune, test, and compare two widely
used fitting codes (GALFIT and GIM2D) for fitting single-component
Sersic models to both simulated and real galaxy data. Our study
focuses on the GEMS survey (Rix et al., 2004ApJS..152..163R 2004ApJS..152..163R) with the
sensitivity of typical HST survey data, and we include our final
catalog of fit results for all 41495 objects detected in GEMS. Using
simulations, we find that fitting accuracy depends sensitively on
galaxy profile shape.
Description:
GEMS (Galaxy Evolution from Morphologies and SEDs) is a large-area
(800arcmin2) two-color (F606W and F850LP) imaging survey with the
Advanced Camera for Surveys on the HST, centered on the CDFS.
GALFIT is a two-dimensional galaxy-fitting software package written by
Peng et al. (2002AJ....124..266P 2002AJ....124..266P) designed to extract structural
components from galaxy images. GIM2D (Galaxy Image 2D) was written by
Luc Simard (2002ApJS..142....1S 2002ApJS..142....1S) as an IRAF package for the
quantitative morphological analysis of galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table9.dat 143 41495 GALFIT fitting results for all GEMS galaxies
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See also:
J/A+A/468/937 : K-band AO imaging in COSMOS deep field (Huertas-Company+, 2007)
J/AJ/122/621 : Galaxy morphology in the CFRS (van den Bergh, 2001)
J/ApJ/542/673 : Morphological types of galaxies in clusters (Fasano+, 2000)
http://archive.stsci.edu/prepds/gems/ : GEMS Home Page
Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 9 F9.6 deg RAdeg Right Ascension in decimal degrees (J2000)
11- 20 F10.6 deg DEdeg Declination in decimal degrees (J2000)
22- 27 A6 --- Gtile The GEMS tile identification
29- 31 I3 --- Seq Object number in SExtractor catalog of Gtile
33- 36 A4 --- --- [GEMS]
37- 55 A19 --- GEMS The GEMS identification (JHHMMSS.SS+DDMMSS.S)
57- 63 F7.2 pix Xpix The X pixel coordinate
65- 71 F7.2 pix Ypix The Y pixel coordinate
73- 78 F6.3 ct Sky Background sky value from GALAPAGOS
80- 84 F5.2 mag F850 The GALFIT derived F850LP band magnitude
86- 89 F4.2 mag e_F850 F850LP band magnitude uncertainty (1)
91- 96 F6.2 pix Re The GALFIT derived half-light radius
98-101 F4.2 pix e_Re Half-light radius uncertainty (1)
103-106 F4.2 --- n The GALFIT derived Sersic index
108-111 F4.2 --- e_n Sersic index uncertainty (1)
113-117 F5.3 --- b/a [0/1] The GALFIT derived axis ratio
119-123 F5.3 --- e_b/a [0/1] Axis ratio uncertainty (1)
125-129 F5.1 deg PAimg [-90/90] Position Angle with respect to the
image (2)
131-135 F5.1 deg PA [-90/90] Position Angle (North through East)
137-139 F3.1 deg e_PA [0.1/8] Position angle uncertainty (1)
141 I1 --- f1 [0/1] Flag for constraint fitting (4)
143 I1 --- f2 [0/1] Flag for science sample (5)
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Note (1): Errors were calculated by a statistical method using the
simulations. See text for details.
Note (2): Derived by GALFIT.
Note (4): value of f1 is:
0 = fit ran into a fitting constraint.
1 = fit did not ran into a fitting constraint.
Note (5): value of f2 is:
0 = object would not be selected for analysis
1 = part of the final galaxy sample used for science according to the
selection criteria given in Barden et al. (2005ApJ...635..959B 2005ApJ...635..959B).
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History:
From electronic version of the journal
References:
Caldwell et al., GEMS Survey Data and Catalog, 2008ApJS..174..136C 2008ApJS..174..136C
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 11-May-2009