J/AJ/135/1858 Old globular clusters in dwarf irregular galaxies (Georgiev+ 2008)
Old globular clusters in Magellanic-type dwarf irregular galaxies.
Georgiev I.Y., Goudfrooij P., Puzia T.H., Hilker M.
<Astron. J., 135, 1858-1876 (2008)>
=2008AJ....135.1858G 2008AJ....135.1858G
ADC_Keywords: Galaxies, nearby ; Clusters, globular ; Photometry ; Morphology
Keywords: galaxies: dwarf - galaxies: irregular - galaxies: stellar content -
globular clusters: general
Abstract:
We have performed a search for old globular clusters (GCs) using
archival F606W and F814W Hubble Space Telescope/Advanced Camera for
Surveys images of 19 Magellanic-type dwarf Irregular (dIrr) galaxies.
Those dIrrs reside in nearby (2-8Mpc) associations of dwarf galaxies
only. All dIrrs have absolute magnitudes fainter than or equal to that
of the SMC (MV=-16.2mag). We detect in total 50 GC candidates in
13 dIrrs, of which 37 have (V-I) colors consistent with "blue"
(old, metal-poor) GCs (bGCs). The luminosity function (LF) of the bGC
candidates in our sample shows a turnover magnitude of
MV=-7.41±0.22mag, consistent with other galaxy types.
Description:
The current study uses Hubble Space Telescope HST archival data of 20
Magellanic-type dIrr galaxies located in nearby (d=3-8Mpc) loose
groups (associations) of dwarf galaxies (Tully et al.,
2006AJ....132..729T 2006AJ....132..729T). They were observed in the F606W and F814W
filters with HST/Advanced Camera for Surveys (ACS) during Cycle 13,
program GO-10210 (PI: B. Tully).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 113 60 *General properties of the GC candidates in the
studied dwarf irregular galaxies
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Note on table3.dat: According to the colors of the GC candidates, they are
separated with lines on blue, red and likely background contamination
sub-populations.
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See also:
J/MNRAS/392/879 : Globular cluster in nearby dwarf galaxies (Georgiev+, 2009)
J/MNRAS/396/1075 : Globular cluster in nearby dwarf gal. II (Georgiev+, 2009)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- [GGP2008] Globular cluster candidate name
15- 22 F8.3 pix Xpos X position
24- 30 F7.2 pix Ypos Y position
32- 33 I2 h RAh Right ascension (J2000)
35- 36 I2 min RAm Right ascension (J2000)
38- 42 F5.2 s RAs Right ascension (J2000)
44 A1 --- DE- Declination sign (J2000)
45- 46 I2 deg DEd Declination (J2000)
48- 49 I2 arcmin DEm Declination (J2000)
51- 55 F5.2 arcsec DEs Declination (J2000)
57- 61 F5.2 mag VMAG0 Deredenned absolute V magnitude
63- 66 F4.2 mag e_VMAG0 rms uncertainty on VMAG0
68- 71 F4.2 mag (V-I)0 Deredenned V-I colour index
73- 76 F4.2 mag e_(V-I)0 rms uncertainty on (V-I)0
78- 82 F5.2 pix rhpix Half-light radius in pixel
84- 87 F4.2 pix e_rhpix rms uncertainty on rhpix
89- 93 F5.2 pc rh Half-light radius in pc
95- 98 F4.2 pc e_rh rms uncertainty on rh
100-103 F4.2 --- ell Ellipticity
105-108 F4.2 kpc d.p Projected distance from galaxy center
110-113 F4.2 --- d.p/r Projected distance normalized to the
effective galaxy radius
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 09-Feb-2010