J/MNRAS/404/1745 Dwarf galaxies in Coma supercluster (Mahajan+, 2010)
Star formation, starbursts and quenching across the Coma supercluster.
Mahajan S., Haines C.P., Raychaudhury S.
<Mon. Not. R. Astron. Soc., 404, 1745-1760 (2010)>
=2010MNRAS.404.1745M 2010MNRAS.404.1745M
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Photometry, SDSS ;
Equivalent widths
Keywords: galaxies: clusters: general - galaxies: evolution -
galaxies: fundamental parameters - infrared: galaxies
Abstract:
We analyse Spitzer Multiband Imaging Photometer (MIPS) 24um
observations, and Sloan Digital Sky Survey Data Release 7 optical
broad-band photometry and spectra, to investigate the star formation
(SF) properties of galaxies residing in the Coma supercluster region.
We find that SF in dwarf galaxies is quenched only in the high-density
environment at the centre of clusters and groups, but that passively
evolving massive galaxies are found in all environments, indicating
that massive galaxies can become passive via internal processes. The
SF-density relation observed for the massive galaxies is weaker
relative to the dwarfs, but both show a trend for the fraction of
star-forming galaxies (fSF) declining to ∼0 in the cluster cores. We
find that active galactic nucleus activity is also suppressed among
massive galaxies residing in the cluster cores.
Description:
We base our work on the photometric and spectroscopic data acquired by
the SDSS Data Release 7 (DR7; Adelman-McCarthy et al.,
2006ApJS..162...38A 2006ApJS..162...38A, Cat. II/267), which for the first time covers the
entire region of the Coma supercluster presented in this paper. Over a
smaller area, we also use archival 24um MIR images, from the MIPS
instrument aboard Spitzer (Rieke et al., 2004ApJS..154...25R 2004ApJS..154...25R),
available over a significant fraction of the two main clusters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 197 Catalogue of Coma galaxies detected at 24um
table3.dat 49 110 Catalogue of dwarf (z>15), k+A [EW(Ha)<2Å and
EW(Hd)←3Å] galaxies in the Coma supercluster
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See also:
II/267 : The SDSS Photometric Catalog, Release 4 (Adelman-McCarthy+, 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 Rigth ascension in decimal degrees (J2000)
10- 16 F7.4 deg DEdeg Declination in decimal degrees (J2000)
18- 23 F6.4 --- z Spectroscopic redshift
25- 32 F8.5 mag gmag SDSS g magnitude
34- 41 F8.5 mag rmag SDSS r magnitude
43- 50 F8.5 mag zmag SDSS z magnitude
52- 59 F8.4 mJy S24 Spitzer/MIPS 24um flux
61 I1 --- cl [0/3] Classification of galaxy (1)
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Note (1): Classification on the basis of BPT diagram (Baldwin, Phillips
& Terlevich, to distinguish AGN/starburst/HII) as follows:
0 = unclassified
1 = star forming galaxy
2 = AGN
3 = AGN according to Miller et al. (2003ApJ...597..142M 2003ApJ...597..142M) criteria (see text)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.4 deg RAdeg Right ascension in decimal degrees (J2000)
10- 16 F7.4 deg DEdeg Declination in decimal degrees (J2000)
18- 23 F6.4 --- z Spectroscopic redshift
25- 32 F8.5 mag zmag SDSS z magnitude
33- 40 F8.4 0.1nm EW(Ha) Hα equivalent width (Å)
42- 49 F8.4 0.1nm EW(Hd) Hδ equivalent width (Å)
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Nomenclature note:
Galaxies identified as [MHR2010] DD.dddd+DD.dddd in Simbad.
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 04-Dec-2010