J/A+A/591/A38 Robust automatic photometry for SDSS gal. (Consolandi+, 2016)
Robust automatic photometry of local galaxies from SDSS.
Dissecting the color magnitude relation with color profiles.
Consolandi G., Gavazzi G., Fumagalli M., Dotti M., Fossati M.
<Astron. Astrophys. 591, A38 (2016)>
=2016A&A...591A..38C 2016A&A...591A..38C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Photometry, CCD
Keywords: galaxies: evolution - galaxies: fundamental parameters -
galaxies: star formation - galaxies: photometry
Abstract:
We present an automatic procedure to perform reliable photometry of
galaxies on SDSS images. We selected a sample of 5853 galaxies in the
Coma and Virgo superclusters. For each galaxy, we derive Petrosian g
and i magnitudes, surface brightness and color profiles. Unlike the
SDSS pipeline, our procedure is not affected by the well known
shredding problem and efficiently extracts Petrosian magnitudes for
all galaxies. Hence we derived magnitudes even from the population of
galaxies missed by the SDSS which represents ∼25% of all Local
supercluster galaxies and 95% of galaxies with g<11mag. After
correcting the g and i magnitudes for Galactic and internal
extinction, the blue and red sequences in the color magnitude diagram
are well separated, with similar slopes. In addition, we study (i) the
color-magnitude diagrams in different galaxy regions, the inner
(r≤1kpc), intermediate (0.2R{Pet}≥r≥0.3R{Pet}) and outer,
disk-dominated (r≥0.35R{Pet})) zone, and (ii), we compute template
color profiles, discussing the dependences of the templates on the
galaxy masses and on their morphological type. The two analyses
consistently lead to a picture where elliptical galaxies show no color
gradients, irrespective of their masses. Spirals, instead, display a
steeper gradient in their color profiles with increasing mass, which
is consistent with the growing relevance of a bulge and/or a bar
component above 1010M☉.
Description:
g- and i-band magnitudes of galaxies in the Local and Coma
supercluster along with g-i colors (corrected for Glactic extinction
and inclination) and masses evaluated following Zibetti et al. 2009
and assuming a Chabrier IMF.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 82 5770 Names, positions, magnitudes colors and masses
(Zibetti et al., 2009MNRAS.400.1181Z 2009MNRAS.400.1181Z)
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [SDSS]
5- 20 A16 --- SDSS SDSS identification (JHHMMSS.s+DDMMSS)
22- 25 I4 --- VCC ? Galaxy VCC identification number
27- 33 A7 --- CGCG ?=0 Galaxy CGCG identification number
35- 38 I4 --- NGC ? Galaxy NGC identification number
40- 48 F9.5 deg RAdeg Right ascension (J2000)
50- 58 F9.5 deg DEdeg Declination (J2000)
60- 64 F5.2 mag gmag Petrosian g-gunn magnitude
66- 70 F5.2 mag imag Petrosian i-gunn magnitude
72- 76 F5.2 mag (g-i)mw0 g-i color corrected for Galactic extinction
and inclination
78- 82 F5.2 [Msun] logM* Masses evaluated following Zibetti et al.
(2009MNRAS.400.1181Z 2009MNRAS.400.1181Z) and assuming a
Chabrier IMF
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Acknowledgements:
Guido Consolandi, Guido.Consolandi(at)mib.infn.it
(End) Guido Consolandi [MIB, Italia], Patricia Vannier [CDS] 08-Apr-2016