J/ApJS/276/34 Spatial distribution of GC systems in early-type gal. (Lim+, 2025)
The spatial distribution of globular cluster systems in early-type galaxies:
estimation procedure and catalog of properties for globular cluster systems
observed with deep imaging surveys.
Lim S., Peng E.W., Cote P., Ferrarese L., Roediger J.C., Liu C.,
Spengler C., Sola E., Duc P.-A., Sales L.V., Blakeslee J.P.,
Cuillandre J.-C., Durrell P.R., Emsellem E., Gwyn S.D.J., Lancon A.,
Marleau F.R., Mihos J.C., Muller O., Puzia T.H., Sanchez-Janssen R.
<Astrophys. J. Suppl. Ser., 276, 34 (2025)>
=2025ApJS..276...34L 2025ApJS..276...34L
ADC_Keywords: Clusters, globular; Galaxies, nearby; Magnitudes, absolute;
Colors; Optical; Surveys
Keywords: Early-type galaxies ; Virgo Cluster ; Globular star clusters ;
Field galaxies ; Galaxy evolution
Abstract:
We present an analysis of the spatial distribution of globular cluster
(GC) systems of 118 nearby early-type galaxies in the Next Generation
Virgo Cluster Survey and Mass Assembly of early-Type GaLAxies with
their fine Structures survey programs, which both used MegaCam on the
Canada-France-Hawaii Telescope. We describe the procedure used to
select GC candidates and fit the spatial distributions of GCs to a
two-dimensional Sersic function, which provides effective radii (half
number radii) and Sersic indices, and estimate background
contamination by adding a constant term to the Sersic function. In
cases where a neighboring galaxy affects the estimation of the GC
spatial distribution in the target galaxy, we fit two two-dimensional
Sersic functions, simultaneously. We also investigate the color
distributions of GCs in our sample by using Gaussian mixture modeling.
For GC systems with bimodal color distributions, we divide the GCs
into blue and red subgroups and fit their respective spatial
distributions with Sersic functions. Finally, we measure the total
number of GCs based on our fitted Sersic function, and calculate the
GC specific frequency.
Description:
In this study, we examine the spatial distribution of globular
clusters (GCs) belonging to 118 early-type galaxies (ETGs) based on
imaging from two large nearby galaxy surveys --the Next Generation
Virgo Cluster Survey (NGVS; PI: Ferrarese, L.,
Ferrarese+ 2012ApJS..200....4F 2012ApJS..200....4F) and Mass Assembly of early-Type
GaLAxies with their fine Structures (MATLAS; PI: Duc, P.-A.,
Duc P.A. 2020arXiv200713874D 2020arXiv200713874D). Additionally, our analysis also uses
Hubble Space Telescope (HST) imaging from the Advanced Camera for
Surveys (ACS) Virgo Cluster Survey (ACSVCS; PI: Cote, P.).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 87 118 List of sample galaxies
table2.dat 117 118 Globular cluster (GC) properties from this study
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See also:
J/ApJ/591/850 : Radial velocities of M49 globular clusters (Cote+, 2003)
J/ApJS/153/223 : ACS Virgo Cluster Survey. I. (Cote+, 2004)
J/MNRAS/355/608 : NGC 4649 (M60) globular clusters (Forbes+, 2004)
J/ApJ/668/209 : HST photometry of NGC 5866 globulars (Cantiello+, 2007)
J/ApJS/169/213 : ACS Fornax Cluster Survey. I. (Jordan+, 2007)
J/ApJS/171/101 : GCs in the ACS Virgo cluster survey (Jordan+, 2007)
J/ApJ/655/144 : ACS Virgo Cluster Survey. XIII. (Mei+, 2007)
J/ApJ/682/135 : CCD photometry of M60 (Lee+, 2008)
J/ApJ/681/197 : ACS Virgo Cluster Survey. XV (Peng+, 2008)
J/MNRAS/385/361 : BVRcIc phot. of NGC 821 globular clusters (Spitler+, 2008)
J/MNRAS/392/879 : Globular clusters in nearby dwarf galaxies (Georgiev+, 2009)
J/MNRAS/413/813 : ATLAS3D project. I. (Cappellari+, 2011)
J/A+A/525/A19 : Phot. of globulars in early galaxies (Chies-Santos+, 2011)
J/MNRAS/420/37 : NGC 4365 globular clusters (Blom+, 2012)
J/MNRAS/436/1172 : Globular Clusters of NGC 4278 in SLUGGS (Usher+, 2013)
J/MNRAS/446/120 : ATLAS3D project. XXIX (Duc+, 2015)
J/ApJ/799/159 : GC populations in S4G galaxies (Zaritsky+, 2015)
J/MNRAS/458/105 : SLUGGS NGC 3607 and 3608 globular clusters (Kartha+, 2016)
J/ApJ/835/123 : Globular clusters in NGC 474 from CFHT obs. (Lim+, 2017)
J/MNRAS/498/2138 : Nearby massive early-type gal. from MATLAS (Bilek+, 2020)
J/ApJ/890/128 : NGVS. XIV. Virgo cluster members (Ferrarese+, 2020)
J/A+A/664/A129 : J-PLUS. Globular clusters candidates (de Brito Silva+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Galaxy name
12- 21 F10.6 deg RAdeg [21.19/345.3] Right ascension (J2000)
23- 31 F9.6 deg DEdeg [-1.16/60.7] Declination (J2000)
33- 38 F6.2 mag gMag [-22.65/-15.4] Absolute g-band magnitude (1)(3)
40- 43 F4.2 mag g-i0 [0.6/1.15] (g'-i')0 color index (1)
45- 50 E6.2 Msun Ms [2e+08/3.7e+11] Galaxy stellar mass (1)
52- 56 F5.1 arcsec Re [4.5/225.6] Galaxy effective radius (1)
58- 61 F4.1 Mpc Dist [10.3/25] Distance (2)
63- 73 A11 --- Survey Survey identifier ("MATLAS", "NGVS" or
"NGVS,ACSVCS")
75- 87 A13 --- OName Other galaxy name(s)
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Note (1): For MATLAS galaxies, magnitudes and colors are from
Sola+ (2022A&A...662A.124S 2022A&A...662A.124S); galaxy stellar masses are taken from
Cappellari+ (2013MNRAS.432.1862C 2013MNRAS.432.1862C); and effective radii are results
of Cappellari+ (2011, J/MNRAS/413/813).
For NGVS galaxies, magnitudes, colors, and effective radii are taken
from Ferrarese+ (2020, J/ApJ/890/128); and galaxy stellar masses are
from Roediger+ (2024, in preparation).
Note (2): The distances are based on HST surface brightness fluctuation
measurements for ACSVCS galaxies (Mei+ 2007, J/ApJ/655/144;
Blakeslee+ 2009ApJ...694..556B 2009ApJ...694..556B), while distances for MATLAS and NGVS
(not in ACSVCS) galaxies are taken from
Cappellari+ (2011, J/MNRAS/413/813).
Note (3): Please note that there is a slight difference between the absolute
g'-magnitudes of the NGVS samples and those presented in Figure 1 of
Lim+ (2024ApJ...966..168L 2024ApJ...966..168L). In Lim+ (2024), we employed model-fitted
magnitudes; however, in this study, we have chosen for curve-of-growth
magnitudes, which we consider to be a more comprehensive magnitude for
estimating the fluxes of galaxies.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
-------------------------------------------------------------------------------
1- 10 A10 --- Name Galaxy name
12- 16 F5.2 arcmin ReGC [0.1/15.8] Effective radius of the GC system,
Re,gc
18- 21 F4.2 arcmin e_ReGC [0.02/1.8] Lower uncertainty on ReGC
23- 26 F4.2 arcmin E_ReGC [0.02/2.9] Upper uncertainty on ReGC
28- 31 F4.2 --- n [0.46/8] Sersic index of the GC system
33- 36 F4.2 --- e_n [0.02/2.8] Lower uncertainty on n
38- 41 F4.2 --- E_n [0.01/4.8] Upper uncertainty on n
43- 47 I5 --- Ngc [6/17730] Total number of GCs
49- 51 I3 --- e_Ngc [3/942] Lower uncertainty on Ngc
53- 56 I4 --- E_Ngc [6/1030] Upper uncertainty on Ngc
58 A1 --- Mod Bimodality of GC color distributions
60- 64 F5.2 arcmin ReBGC [0.2/15.3]? Effective radius of blue GC system,
Re,bgc
66- 69 F4.2 arcmin e_ReBGC [0.02/2]? Lower uncertainty on ReBGC
71- 74 F4.2 arcmin E_ReBGC [0.03/2.8]? Upper uncertainty on ReBGC
76- 79 F4.2 arcmin ReRGC [0.08/5.7]? Effective radius of red GC system,
Re,rgc
81- 84 F4.2 arcmin e_ReRGC [0.01/1.6]? Lower uncertainty on ReRGC
86- 89 F4.2 arcmin E_ReRGC [0.03/3.4]? Upper uncertainty on ReRGC
91- 94 F4.2 mag g-i0B [0.6/0.81]? (g-i)0,b peak color of blue
GC system
96- 99 F4.2 mag g-i0R [0.8/1.2]? (g-i)0,r peak color of red
GC system
101- 104 F4.2 mag g-i0m [0.6/2.2]? (g-i)0,m median GC color;
for unimodal GC color distributions
106- 109 F4.1 --- SNg [0.1/29.2] GC specific frequency, SN,g' (4)
111- 113 F3.1 --- e_SNg [0.1/6.9] Lower uncertainty on SNg
115- 117 F3.1 --- E_SNg [0.1/8.4] Upper uncertainty on SNg
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Note (4): Traditionally, GC specific frequency is calculated with the V-band
absolute magnitude of the host galaxy, but we estimated it with g'-band
absolute magnitude of the host galaxy. We calculate GC specific
frequency (SN,g') with the following equation (9):
SN,g'=NGCx100.4(Mg'+15)
See Section 3.1.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 21-Jan-2026