J/ApJ/685/904 Metal-rich dwarf galaxies from SDSS-DR4 (Peeples+, 2008)
Outliers from the mass-metallicity relation.
I. A sample of metal-rich dwarf galaxies from SDSS.
Peeples M.S., Pogge R.W., Stanek K.Z.
<Astrophys. J., 685, 904-914 (2008)>
=2008ApJ...685..904P 2008ApJ...685..904P
ADC_Keywords: Galaxies, optical ; Redshifts ; Abundances
Keywords: galaxies: abundances - galaxies: dwarf - galaxies: evolution
Abstract:
We have identified a sample of 41 low-mass high-oxygen abundance
outliers from the mass-metallicity relation of star-forming galaxies
measured by Tremonti et al. (2004ApJ...613..898T 2004ApJ...613..898T). These galaxies,
which have 8.6<12+log(O/H)<9.3 over a range of -14.4>MB>-19.1 and
7.4<log(M*/M☉)<10, are surprisingly nonpathological. They
have typical specific star formation rates, are fairly isolated, and,
with few exceptions, have no obvious companions. Morphologically, they
are similar to dwarf spheroidal or dwarf elliptical galaxies. We
predict that their observed high oxygen abundances are due to
relatively low gas fractions, concluding that these are transitional
dwarf galaxies nearing the end of their star formation activity.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 41 Full sample of low-luminosity mass-metallicity
outliers
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/ApJ/695/259 : Massive metal-poor galaxies from SDSS (Peeples+, 2009)
J/ApJ/676/286 : Spectral templates for galaxies from 0.2 to 10um (Assef+,
2008)
J/A+A/459/85 : O/H and gas densities in star-forming galaxies (Nagao+, 2006)
J/A+A/448/955 : Abundances of emission galaxies in SDSS-DR3 (Izotov+, 2006)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.4 deg RAdeg Right ascension in decimal degrees (J2000)
10- 17 F8.5 deg DEdeg Declination in decimal degrees (J2000)
19- 22 F4.2 [-] eps(O) Oxygen abundance (12+log(O/H)) from Tremonti
et al. 2004ApJ...613..898T 2004ApJ...613..898T
24- 29 F6.2 [-] BMAG Absolute B-band magnitude (MB) (1)
31- 34 F4.2 [-] logM* Stellar mass from Tremonti et al.
2004ApJ...613..898T 2004ApJ...613..898T (2)
36- 41 F6.4 --- z Spectroscopic redshift not corrected for
peculiar velocities
43- 61 A19 --- Note Note
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Note (1): MB is measured using the low-resolution templates of Assef et
al. (2008, Cat. J/ApJ/676/286) and corrected where necessary for
peculiar velocities, as discussed in section 2.
Note (2): Sample of metal-rich dwarf galaxies, sorted by MB. First 16
lines (above the horizontal line) are the very low mass
(log[M*/M☉]<9.1) sample.
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History:
From electronic version of the journal
References:
Peeples et al. Paper II. 2009ApJ...695..259P 2009ApJ...695..259P Cat. J/ApJ/695/259
(End) Emmanuelle Perret [CDS] 04-Apr-2011