J/MNRAS/459/4450 Peculiar compact stellar systems in Fornax (Wittmann+, 2016)
Peculiar compact stellar systems in the Fornax cluster.
Wittmann C., Lisker T., Pasquali A., Hilker M., Grebel E.K.
<Mon. Not. R. Astron. Soc., 459, 4450-4466 (2016)>
=2016MNRAS.459.4450W 2016MNRAS.459.4450W (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Radial velocities ; Morphology
Keywords: galaxies: clusters: individual: Fornax - galaxies: dwarf -
galaxies: nuclei; galaxies: peculiar -
galaxies: star clusters: general - galaxies: structure
Abstract:
We search for hints to the origin and nature of compact stellar
systems in the magnitude range of ultracompact dwarf galaxies in deep
wide-field imaging data of the Fornax cluster core. We visually
investigate a large sample of 355 spectroscopically confirmed cluster
members with V-band equivalent magnitudes brighter than -10mag for
faint extended structures. Our data reveal peculiar compact stellar
systems, which appear asymmetric or elongated from their outer light
distribution. We characterize the structure of our objects by
quantifying their core concentration, as well as their outer asymmetry
and ellipticity. For the brighter objects of our sample we also
investigate their spatial and phase-space distribution within the
cluster. We argue that the distorted outer structure alone that is
seen for some of our objects, is not sufficient to decide whether
these systems have a star cluster or a galaxy origin. However, we find
that objects with low core concentration and high asymmetry (or high
ellipticity) are primarily located at larger cluster-centric distances
as compared to the entire sample. This supports the hypothesis that at
least some of these objects may originate from tidally stripped
galaxies.
Description:
The data are fully characterized by Lisker et al. (2016, A&A,
submitted). They were acquired in 2008 and 2010 with the WFI at the
ESO/MPG 2.2m telescope (programmes 082.A-9016 and 084.A-9014, PI A.
Pasquali, Guaranteed Time of the Max Planck Institute for Astronomy).
We used a transparent filter that nearly equals the no-filter
throughput (>10 per cent in the range 350-900nm) and thus provides
a high signal-to-noise ratio.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 69 904 Compilation of compact stellar systems known to
be Fornax cluster members, based on previous
publications
table3.dat 71 355 Parameter catalogue for the working sample of
spectroscopically confirmed Fornax cluster
members with mVe<21.5mag
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/904] Sequential number
5- 6 I2 h RAh Right ascension (J2000)
8- 9 I2 min RAm Right ascension (J2000)
11- 15 F5.2 s RAs Right ascension (J2000)
17 A1 --- DE- Declination sign (J2000)
18- 19 I2 deg DEd Declination (J2000)
21- 22 I2 arcmin DEm Declination (J2000)
24- 27 F4.1 arcsec DEs Declination (J2000)
29- 57 A29 --- Simbad Object identifier of the SIMBAD database,
referring to the publication the object
was taken from
59- 62 I4 km/s HV Heliocentric velocity with the smallest error
from all compiled velocities for an object
64- 66 I3 km/s e_HV rms uncertainty in HV
68- 69 I2 --- r_HV Literature source for the adopted velocity (1)
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Note (1): References as follows:
1 = Schuberth et al. (2010, Cat. J/A+A/513/A52)
2 = Dirsch et al. (2004, Cat. J/AJ/127/2114)
3 = Bergond et al. (2007, Cat. J/A+A/464/L21)
4 = Firth et al. (2007, Cat. J/MNRAS/382/1342)
5 = Gregg et al. (2009, Cat. J/AJ/137/498)
6 = Mieske et al. (2004, Cat. J/A+A/418/445)
7 = Mieske et al. (2002, Cat. J/A+A/383/823)
8 = Firth et al. (2008MNRAS.389.1539F 2008MNRAS.389.1539F)
9 = Kissler-Patig et al. (1999AJ....117.1206K 1999AJ....117.1206K)
10 = Drinkwater et al. (2000PASA...17..227D 2000PASA...17..227D)
11 = Kissler-Patig et al. (1998AJ....115..105K 1998AJ....115..105K)
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 ---- Seq [1/904] Sequential number
5- 10 F6.3 mag Vemag Apparent V-equivalent magnitude
12- 16 F5.3 mag e_Vemag rms uncertainty on Vemag
18 I1 --- f_Vemag [1/2] Magnitude flag (1)
20- 24 F5.3 --- CC Core concentration (uncorrected values)
26- 30 F5.3 --- CCcorr PSF-corrected core concentration
32- 38 F7.3 --- RA ?=-99 Residual asymmetry
40- 46 F7.3 --- e_RA ?=-99 rms uncertainty on RA
48- 54 F7.3 --- Ell ?=-99 Ellipticity
56- 62 F7.3 --- e_Ell ?=-99 rms uncertainty on Ell
64- 65 I2 --- Sub ? Subsample (2)
67- 68 I2 --- SubAlt ? Alternative subsample (2)
70- 71 I2 --- Region PSF-region of the object
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Note (1): Magnitude flag as follows:
1 = mag and e_mag obtained from SExtractor
2 = mag and e_mag obtained from PSF-fitting
Note (2): Subsamples as follows:
1 = cc+ra
2 = cc+RA
3 = CC+RA
4 = cc+EL
0 = SUB: object not part of any subsample
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Sep-2017