J/MNRAS/435/3444 ALHAMBRA survey morphological catalogue (Povic+, 2013)
The ALHAMBRA survey: reliable morphological catalogue of 22 051 early-
and late-type galaxies.
Povic M., Huertas-Company M., Aguerri J.A.L., Marquez I., Masegosa J.,
Husillos C., Molino A., Cristobal-Hornillos D., Perea J., Benitez N.,
Del Olmo A., Fernandez-Soto A., Jimenez-Teja Y., Moles M., Alfaro E.,
Aparicio-Villegas T., Ascaso B., Broadhurst T., Cabrera-Cano J.,
Castander F.J., Cepa J., Fernandez Lorenzo M., Cervino M.,
Gonzalez Delgado R.M., Infante L., Lopez-Sanjuan C., Martinez V.J.,
Matute I., Oteo I., Perez-Garcia A.M., Prada F., Quintana J.M.
<Mon. Not. R. Astron. Soc., 435, 3444-3461 (2013)>
=2013MNRAS.435.3444P 2013MNRAS.435.3444P
ADC_Keywords: Surveys ; Galaxy catalogs ; Morphology
Keywords: surveys - galaxies: fundamental parameters - galaxies: statistics
Abstract:
Advanced Large Homogeneous Area Medium Band Redshift Astronomical
(ALHAMBRA) is photometric survey designed to trace the cosmic
evolution and cosmic variance. It covers a large area of ∼4deg2 in
eight fields, where seven fields overlap with other surveys, allowing
us to have complementary data in other wavelengths. All observations
were carried out in 20 continuous, medium band (30nm width) optical
and 3 near-infrared (JHK) bands, providing the precise measurements of
photometric redshifts. In addition, morphological classification of
galaxies is crucial for any kind of galaxy formation and cosmic
evolution studies, providing the information about star formation
histories, their environment and interactions, internal perturbations,
etc. We present a morphological classification of >40000 galaxies in
the ALHAMBRA survey. We associate to every galaxy a probability to be
early type using the automated Bayesian code galsvm. Despite of the
spatial resolution of the ALHAMBRA images (∼1arcsec), for 22051
galaxies, we obtained the contamination by other type of less than 10
percent. Of those, 1640 and 10322 galaxies are classified as early-
(down to redshifts ∼0.5) and late-type (down to redshifts ∼1.0),
respectively, with magnitudes F613W≤22.0. In addition, for
magnitude range 22.0<F613W≤23.0, we classified other 10089
late-type galaxies with redshifts ≤1.3. We show that the classified
objects populate the expected regions in the colour-mass and
colour-magnitude planes. The presented data set is especially
attractive given the homogeneous multiwavelength coverage available in
the ALHAMBRA fields, and is intended to be used in a variety of
scientific applications. The low-contamination catalogue (<10 percent)
is made publicly available with this paper.
Description:
The ALH observations were carried out at the Calar Alto German-Spanish
Astronomical Center (CAHA3), under the Spanish guaranteed time of 110
nights. Eight fields were observed in the Northern hemisphere sky,
having a seeing lower than 1.6arcsec (ranging mainly between 0.8 and
1.2arcsec).
Each ALH detection was observed in 23 bands, with 20 optical and three
standard JHK NIR filters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 196 22051 Morphological catalogue of 22051 galaxies classified
classified in the ALH survey with contamination<10%
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID [1/22051] Sequential number
7- 18 A12 --- Field ALH field, pointing and CCD (FIELDPCCD)
20- 23 I4 --- IDph Identification number in the photometric
catalogue (ID_phot) (1)
25- 35 I11 --- IDz [81421100234/81482410356] Identification
number in the photometric redshift
catalogue (ID_zphot) (2)
37- 46 F10.6 deg RAdeg Right ascension of the centroid (RA) (J2000)
48- 56 F9.6 deg DEdeg Declination of the centroid (DEC) (J2000)
58 I1 -- f_ID [0/2] SExtractor flag: 0=good,
2=possibly blended sources (FLAGS)
60- 65 F6.3 mag F458W Apparent magnitude in the F458W band (m458)
67- 71 F5.3 mag e_F458W rms uncertainty on F458W (errm458)
73- 78 F6.3 mag F613W Apparent magnitude in the F613W band (m613)
80- 84 F5.3 mag e_F613W rms uncertainty on F613W (errm613)
86- 91 F6.3 mag F892W Apparent magnitude in the F892W band (m892)
93- 97 F5.3 mag e_F892W rms uncertainty on F892W (errm892)
99-105 F7.4 [kpc] logR50 [-0.5/1.3] log(radius at 50% of flux)
107-113 F7.4 [kpc] logR90 [-0.1/2.0]?=- log(radius at 90% of flux)
115-121 F7.4 mag/arcsec2 <SuBr> Mean surface brightness measured by galSVM
(MUMEAN) (5)
123-128 F6.4 --- ell [0/1] source ellipticity (ELLIPTICITY)
130-136 F7.4 --- ASYM [-0.1/1] galSVM asymmetry index (5)
138-143 F6.4 --- CAbr [0/1] galSVM Abraham concentration index
(fluxes at 30 and 90% radius) (CABR) (5)
145-150 F6.4 --- Gini [0/1] galSVM Gini coefficient (GINI) (5)
152-158 F7.4 --- Smooth [-0.1/1] galSVM source smoothness, measures
relevance of small-scale structures (5)
160-166 F7.4 --- M20 [-2.4/0] galSVM M20 moment of light (5)
168-173 F6.4 --- CCon [1/4.2] galSVM Conselice-Bershady
concentration index (ratio of circular radii
with 20% and 80% of total flux) (CCON) (5)
175-180 F6.4 --- pET [0/1] Averaged probability that the galaxy
is ET (early-type) (pE10-AVG) (3)
182-187 F6.4 --- e_pET rms uncertainty on pET (errpE10-AVG)
189-190 A2 --- Cl [ET/LT] Final morphological class (Early or
Late) (CLASS) (4)
192-196 F5.3 --- zph [0/1.3] Photometric redshift (REDSHIFT) (2)
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Note (1): Husillos et al., in preparation, equal to NUMBER parameter in the
original catalogue.
Note (2): Molino et al., 2014MNRAS.441.2891M 2014MNRAS.441.2891M; our IDph (ID_phot) number is
equal to ID parameter in the original catalogue.
Note (3): The probability is measured from other 15 probabilities (see
Section 3.2.2). It takes values from 0 to 1, where small values indicate
that the galaxy is late-type.
Note (4): after applying the probability cuts described in Sect. 4;
ET = early-type: elliptical and lenticular
LT = late-type; spiral and irregular
Note (5): galSVM (classification of high-redshift galaxies using Support
Vector Machines): see Huertas-company et al. (2008A&A...478..971H 2008A&A...478..971H)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 11-Oct-2014