J/ApJ/860/4 NGFS. IV. The Fornax core region (Ordenes-Briceno+, 2018)
The Next Generation Fornax Survey (NGFS).
IV. Mass and age bimodality of nuclear clusters in the Fornax core region.
Ordenes-Briceno Y., Puzia T.H., Eigenthaler P., Taylor M.A., Munoz R.P.,
Zhang H., Alamo-Martinez K., Ribbeck K.X., Grebel E.K., Angel S., Cote P.,
Ferrarese L., Hilker M., Lancon A., Mieske S., Miller B.W., Rong Y.,
Sanchez-Janssen R.
<Astrophys. J., 860, 4-4 (2018)>
=2018ApJ...860....4O 2018ApJ...860....4O (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy; Galaxies, dwarf; Photometry, ugriz
Keywords: galaxies: clusters: Fornax; galaxies: dwarf; galaxies: nuclei
Abstract:
We present the analysis of 61 nucleated dwarf galaxies in the central
regions (≲Rvir/4) of the Fornax galaxy cluster. The galaxies and
their nuclei are studied as part of the Next Generation Fornax Survey
using optical imaging obtained with the Dark Energy Camera mounted at
Blanco/Cerro Tololo Inter-American Observatory and near-infrared data
obtained with VIRCam at VISTA/ESO. We decompose the nucleated dwarfs
in nucleus and spheroid, after subtracting the surface brightness
profile of the spheroid component and studying the nucleus using point
source photometry. In general, nuclei are consistent with colors of
confirmed metal-poor globular clusters, but with significantly smaller
dispersion than other confirmed compact stellar systems in Fornax. We
find a bimodal nucleus mass distribution with peaks located at
log(M*/M☉)∼5.4 and ∼6.3. These two nucleus subpopulations have
different stellar population properties: the more massive nuclei are
older than ∼2Gyr and have metal-poor stellar populations
(Z≲0.02Z☉), while the less massive nuclei are younger than
∼2Gyr with metallicities in the range 0.02<Z/Z☉≤1. We find that
the nucleus mass (Mnuc) versus galaxy mass (Mgal) relation becomes
shallower for less massive galaxies starting around 108M☉, and
the mass ratio ηn=Mnuc/Mgal shows a clear anticorrelation
with Mgal for the lowest masses, reaching 10%. We test current
theoretical models of nuclear cluster formation and find that they
cannot fully reproduce the observed trends. A likely mixture of in
situ star formation and star cluster mergers seems to be acting during
nucleus growth over cosmic time.
Description:
The Next Generation Fornax Survey (NGFS) uses the Cerro Tololo
Inter-American Observatory (CTIO) 4m Blanco telescope in combination
with the Dark Energy Camera (DECam) for optical photometry, as well as
the European Southern Observatory (ESO) 3.7m VISTA telescope and
VIRCam for near-infrared (NIR) photometry. The current NGFS survey
footprint covers 50deg2 with 19 DECam tiles of 2.65deg2 each and
detects point sources at signal-to-noise ratio (S/N)=5 down to
u'=26.5, g'=26.1, i'=25.3, J=24.0, and Ks=23.3 AB mag.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 126 61 Nuclear star cluster parameters
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/AJ/127/105 : Star clusters in late-type spiral gal. (Boker+, 2004)
J/ApJ/621/673 : Line indices for 124 early-type galaxies (Thomas+, 2005)
J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)
J/MNRAS/396/1075 : Globular cluster in nearby dwarf gal. II (Georgiev+, 2009)
J/MNRAS/414/3699 : Study of hot stellar systems and galaxies (Misgeld+, 2011)
J/ApJ/763/40 : UBVI phot. of GCs in the Fornax galaxy cluster (Kim+, 2013)
J/A+A/566/A47 : MW nuclear star cluster extinction map (Schoedel+, 2014)
J/MNRAS/441/3570 : Nuclear star clusters in 228 spiral gal. (Georgiev+, 2014)
J/MNRAS/445/2385 : HST/ACS Coma Cluster Survey. X. (den Brok+, 2014)
J/ApJ/813/L15 : Dwarf galaxies in Fornax cluster from NGFS (Munoz+, 2015)
J/MNRAS/457/2122 : Nuclear star clusters photometric masses (Georgiev+, 2016)
J/MNRAS/459/4450 : Peculiar compact stellar systems in Fornax (Wittmann+, 2016)
J/ApJS/227/12 : NGVS XXV. Virgo globular clusters phot. (Powalka+, 2016)
J/ApJ/855/142 : Next Generation Fornax Survey. II. (Eigenthaler+, 2018)
J/ApJ/858/118 : Kinematic data of 3 nearby low-mass galaxies (Nguyen+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
-------------------------------------------------------------------------------
1- 4 A4 --- --- [NGFS]
5- 17 A13 --- NGFS NGFS name (HHMMSS+DDMMSS; J2000)
18 A1 --- --- [n]
20- 21 I2 h RAh Hour of right ascension (J2000)
23- 24 I2 min RAm Minute of right ascension (J2000)
26- 30 F5.2 s RAs Second of right ascension (J2000)
32 A1 --- DE- Sign of declination (J2000)
33- 34 I2 deg DEd Degree of declination (J2000)
36- 37 I2 arcmin DEm Arcminute of declination (J2000)
39- 42 F4.1 arcsec DEs Arcsecond of declination (J2000)
44- 49 F6.3 mag upmag [20.78/25.1]? CTIO/DECam u'-band AB magnitude
51- 55 F5.3 mag e_upmag [0.005/0.2]? Uncertainty on the upmag
57- 62 F6.3 mag gpmag [19.6/26.2]? CTIO/DECam g'-band AB magnitude
64- 68 F5.3 mag e_gpmag [0.002/0.2]? Uncertainty on the gpmag
70- 75 F6.3 mag ipmag [18.7/25.1]? CTIO/DECam i'-band AB magnitude
77- 82 F6.4 mag e_ipmag [0.001/0.2]? Uncertainty on the ipmag
84- 89 F6.3 mag Jmag [18.38/23.92]? VISTA/VIRCam J-band AB magnitude
91- 95 F5.3 mag e_Jmag [0.002/0.2]? Uncertainty on the Jmag
97- 102 F6.3 mag Ksmag [18.2/23.1]? VISTA/VIRCam Ks-band AB magnitude
104- 108 F5.3 mag e_Ksmag [0.003/0.2]? Uncertainty on the Ksmag
110- 114 F5.3 [Msun] logM [4.8/7.3]? Log of stellar mass
116- 120 F5.3 [Msun] e_logM [0.001/0.4]? Lower uncertainty on logM
122- 126 F5.3 [Msun] E_logM [0.001/0.5]? Upper uncertainty on logM
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History:
From electronic version of the journal
References:
Munoz et al. Paper I. 2015ApJ...813L..15M 2015ApJ...813L..15M Cat. J/ApJ/813/L15
Eigenthaler et al. Paper II. 2018ApJ...855..142E 2018ApJ...855..142E Cat. J/ApJ/855/142
Ordenes-Briceno et al. Paper III. 2018ApJ...859...52O 2018ApJ...859...52O Cat. J/ApJ/859/52
Ordenes-Briceno et al. Paper IV. 2018ApJ...860....4O 2018ApJ...860....4O This catalog
(End) Emmanuelle Perret [CDS] 28-Sep-2023