J/A+A/488/1167 Photometry of bulges at intermediate z (Dominguez-Palmero+, 2008)
Bulges of disk galaxies at intermediate redshifts.
I. Samples with and without bulges in the Groth Strip Survey.
Dominguez-Palmero L., Balcells M., Erwin P., Prieto M.,
Cristobal-Hornillos D., Eliche-Moral M.C., Guzman R.
<Astron. Astrophys. 488, 1167 (2008)>
=2008A&A...488.1167D 2008A&A...488.1167D
ADC_Keywords: Galaxy catalogs ; Galaxies, photometry ; Photometry, HST ;
Photometry, surface ; Colors ; Redshifts
Keywords: galaxies: bulges - galaxies: evolution - galaxies: formation -
galaxies: fundamental parameters - galaxies: high-redshift -
galaxies: photometry
Abstract:
Analysis of bulges to redshifts of up to z=1 have provided ambiguous
results as to whether bulges as a class are old structures akin to
elliptical galaxies or younger products of the evolution of their host
disks. We aim to define a sample of intermediate-z disk galaxies
harbouring central bulges, and a complementary sample of disk galaxies
without measurable bulges. We intend to provide colour profiles for
both samples, as well as measurements of nuclear, disk, and global
colours, which may be used to constrain the relative ages of bulges
and disks. We select a diameter-limited sample of galaxies in images
from the HST/WFPC2 (Wide-Field Planetary Camera 2 at the Hubble Space
Telescope) Groth Strip survey, which is divided into two subsamples of
higher and lower inclination to assess the role of dust in the
measured quantities. Mergers are visually identified and excluded. We
take special care to control the pollution by ellipticals. The bulge
sample is defined with a criterion based on nuclear surface brightness
excess over the inward extrapolation of the exponential law fitted to
the outer regions of the galaxies. We extract colour profiles on the
semi-minor axis least affected by dust in the disk, and measure
nuclear colours at 0.85kpc from the centre over those profiles. Disk
colours are measured on major axis profiles; global colours are
obtained from 2.6" diameter apertures. Colour transformations and
K-corrections are calculated using SEDs covering bands UBVIJK, from
the GOYA photometric survey. We obtain a parent sample containing 248
galaxies with known redshifts, spectroscopic or photometric, spanning
0.1<z<1.2. The bulge subsample comprises 54 galaxies (21.8% of the
total), while the subsample with no measureable bulges is 55.2% of the
total (137 galaxies). The remainder (23%) is composed of mergers. We
list nuclear, disk, and global colours (observed and rest-frame) and
magnitudes (apparent and absolute), as well as galaxy colour gradients
for the samples with and without bulges, and make them available in
electronic format. We also provide images, colour maps, plots of
spectral energy distributions, major-axis surface brightness profiles,
and minor-axis colour profiles for both samples.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 70 54 Bulge sample data
tablea2.dat 70 137 Non-bulge sample data
tablea3.dat 67 54 Bulge sample colours
tablea4.dat 67 137 Non-bulge sample colours
tablea5.dat 43 54 Bulge sample colour gradients
tablea6.dat 43 137 Non-bulge sample colour gradients
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See also:
J/ApJS/159/41 : DEEP Groth Strip Survey. I. (Vogt+, 2005)
J/ApJS/142/1 : DEEP Groth Strip Survey. II. (Simard+, 2002)
J/ApJ/599/1006 : DEEP Groth Strip Survey. VII. (Kobulnicky+, 2003)
J/ApJS/157/175 : DEEP Groth Strip Survey. VIII. (Koo+, 2005)
J/ApJ/571/136 : DEEP Groth Strip survey. X. (Im+, 2002)
J/MNRAS/356/568 : Deep Chandra survey of Groth Strip (Nandra+, 2005)
J/MNRAS/371/221 : Deep Chandra survey of Groth Strip. II. (Georgakakis+, 2006)
Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Source number identification
6- 23 A18 --- Name Source name, based on J2000 coordinates
(HHMMSS.ss+DDMMSS.s)
25- 30 F6.4 --- z Source redshift
32 I1 --- q_z [1/2] Redshift quality:
1=spectroscopic, 2=photometric
34- 37 F4.2 arcsec R Source semi-major axis in arcsec from
SExtractor A size parameter
39- 42 F4.2 --- e Source ellipticity from SExtractor (1-b/a)
44- 45 A2 --- Sample [hi li] Subsample from which the source comes:
hi = high-inclination sample
li = low-inclination sample
47- 51 F5.2 mag I814 Total I814 magnitude of galaxy from
SExtractor MAG_BEST magnitude
53- 56 F4.2 mag e_I814 Error in total I814 magnitude of galaxy
58- 63 F6.2 mag BMAG Galaxy absolute magnitude in B-band (1)
65- 70 F6.2 mag RMAG Galaxy absolute magnitude in R-band (1)
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Note (1): The total errors in galaxy absolute magnitude come from the sum
in quadrature of the measured error in observed F814W magnitude and
the error derived from redshift uncertainty and SED choice (see Sect. 5.4)
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Byte-by-byte Description of file: tablea3.dat tablea4.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Source number identification
6- 9 F4.2 mag (V-I)b Observed nuclear (V606-I814) colour index,
measured at 0.85kpc from the centre
11- 14 F4.2 mag e_(V-I)b Error in observed nuclear (V606-I814) colour
16- 19 F4.2 mag (V-I)d ?=- Observed disk (V606-I814) colour,
measured in the range between 1 and 2 times
the scale length of the exponential law fit
to the outer regions of the galaxies
21- 24 F4.2 mag e_(V-I)d ?=- Error in observed disk (V606-I814)
colour index
26- 29 F4.2 mag (V-I)g Observed global (V606-I814) colour index,
measured within a 2.6" diameter aperture
31- 34 F4.2 mag e_(V-I)g Error in observed global (V606-I814)
colour index (1)
36- 40 F5.2 mag (U-B)b Rest-frame nuclear (U-B) colour index
42- 46 F5.2 mag (U-B)d ?=- Rest-frame disk (U-B) colour index
48- 52 F5.2 mag (U-B)g Rest-frame global (U-B) colour index
54- 57 F4.2 mag (B-R)b Rest-frame nuclear (B-R) colour index
59- 62 F4.2 mag (B-R)d ?=- Rest-frame disk (B-R) colour index
64- 67 F4.2 mag (B-R)g Rest-frame global (B-R) colour index
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Note (1): The total errors in rest-frame colours come from the sum in
quadrature of the measured error in observed (V606-I814) colour and
the error derived from the colour transformation (see Sect. 5.4).
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Byte-by-byte Description of file: tablea5.dat tablea6.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- Seq Source number identification
6- 11 F6.3 mag/kpc g(V-I)b Colour gradient(V606-I814) calculated over the
bluer semi-minor axes colour profile (1)
13- 17 F5.3 mag/kpc e_g(V-I)b Error in g(V-I)b (2)
19- 24 F6.3 mag/kpc g(V-I)r Colour gradient(V606-I814) calculated over the
redder semi-minor axes colour profile (1)
26- 30 F5.3 mag/kpc e_g(V-I)r Error on g(V-I)r (2)
32- 37 F6.3 mag/kpc g(V-I)s Colour gradient(V606-I814) calculated over the
averaged semi-major axes colour profile (1)
39- 43 F5.3 mag/kpc e_g(V-I)s Error on g(V-I)s (2)
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Note (1): The colour gradients are measured in magnitudes per deprojected kpc.
Note (2): The errors are the 1-sigma uncertainty estimates for the returned
parameters of the linear fits.
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Acknowledgements:
L. Dominguez-Palmero, ldp(at)iac.es
(End) Patricia Vannier [CDS] 04-Jul-2008