J/A+A/611/A93 NGC3115 & NGC1399 VEGAS-SSS globular clusters (Cantiello+, 2018)
VEGAS-SSS. II. Comparing the globular cluster systems in NGC3115 and NGC1399
using VEGAS and FDS survey data.
Cantiello M., D'Abrusco R., Spavone M., Paolillo M., Capaccioli M.,
Limatola L., Grado A., Iodice E., Raimondo G., Napolitano N.,
Blakeslee J.P., Brocato E., Forbes D.A., Hilker M., Mieske S., Peletier R.,
Van de Ven G., Schipani P.
<Astron. Astrophys. 611, A93 (2018)>
=2018A&A...611A..93C 2018A&A...611A..93C (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Clusters, globular
Keywords: galaxies: elliptical and lenticular, cD -
galaxies: star clusters: general -
galaxies: individual: NGC 3115, NGC 1399 -
galaxies: clusters: individual: Fornax - galaxies: evolution -
galaxies: stellar content
Abstract:
We analyze the globular cluster (GC) systems in two very different
galaxies, NGC 3115 and NGC 1399. With the papers of this series, we
aim at highlighting common and different properties in the GC systems
in galaxies covering a wide range of parameter space. We compare the
GCs in NGC 3115 and NGC 1399 as derived from the analysis of one
square degree u-, g-, and i-band images taken with the VST telescope
as part of the VST early-type galaxy survey (VEGAS) and Fornax deep
survey (FDS). We selected GC candidates using as reference the
morpho-photometric and color properties of confirmed GCs. The surface
density maps of GCs in NGC 3115 reveal a morphology similar to the
light profile of field stars; the same is true when blue and red GCs
are taken separately. The GC maps for NGC 1399 are richer in structure
and confirm the existence of an intra-cluster GC component. We confirm
the presence of a spatial offset in the NGC 1399 GC centroid and find
that the centroid of the GCs for NGC 3115 coincides well with the
galaxy center. Both GC systems show unambiguous color bimodality in
(g-i) and (u-i); the color-color relations of the two GC systems
are slightly different with NGC 3115 appearing more linear than NGC
1399. The azimuthal average of the radial density profiles in both
galaxies reveals a larger spatial extent for the total GCs population
with respect to the galaxy surface brightness profile. For both
galaxies, the red GCs have radial density profiles compatible with the
galaxy light profile, while the radial profiles for blue GCs are
shallower. As for the specific frequency of GCs, SN, we find it is a
factor of two higher in NGC 1399 than for NGC 3115; this is mainly the
result of extra blue GCs. By inspecting the radial behavior of the
specific frequency, SN(<r), for the total, blue, and red GCs, we
find notable similarities between the trends for red GCs in the two
targets. In spite of extremely different host environments, the red
GCs in both cases appear closely linked to the light distribution of
field stars. Blue GCs extend to larger galactocentric scales than red
GCs, marking a significant difference between the two galaxies: the
blue/red GCs and field stellar components of NGC 3115 appear well
thermalized with each other and the blue GCs in NGC 1399 appear to
fade into an unrelaxed intra-cluster GC population.
Description:
Photometric catalogs for globular cluster (GC) candidates over the the
1 sq. degree area around NGC3115 and NGC1399 (ngc3115.dat and
ngc1399.dat). The catalogues are based on u-, g- and i- band images
from the VST elliptical galaxies survey (VEGAS). Aperture magnitudes,
corrected for aperture correction are reported. We also provide the
full catalogs of matched sources, which also include the matched
background and foreground sources in the frames (ngc3115_full.dat and
ngc1399_full.dat).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
ngc3115.dat 72 1707 Globular cluster candidates positions and
magnitudes in NGC3115
ngc1399.dat 72 1589 Globular cluster candidates positions and
magnitudes in NGC1399
n3115all.dat 72 78465 Full list of ugi matched sources in the
1 sq. deg area around NGC3115
n1399all.dat 72 20779 Full list of ugi matched sources in the
1 sq. deg area around NGC1399
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See also:
J/ApJ/808/19 : Megasecond Chandra XVP obs. of NGC3115. II. (Lin+, 2015)
J/A+A/576/A14 : VEGAS-SSS photometry of NGC3115 (Cantiello+, 2015)
J/A+A/586/A102 : UCDs in the halo of NGC1399 (Voggel+, 2016)
J/A+A/611/A21 : Globular cluster candidates in NGC253 (Cantiello+, 2017)
Byte-by-byte Description of file: *.dat
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Bytes Format Units Label Explanations
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1- 10 F10.6 deg RAdeg Right ascension (J2000.0)
12- 21 F10.6 deg DEdeg Declination (J2000.0)
23- 30 F8.4 mag umag VST u-band aperture magnitude (1)
32- 38 F7.4 mag e_umag VST u-band magnitude error
40- 47 F8.4 mag gmag VST g-band aperture magnitude (1)
49- 55 F7.4 mag e_gmag VST g-band magnitude error
57- 64 F8.4 mag imag VST i-band aperture magnitude (1)
66- 72 F7.4 mag e_imag VST i-band magnitude error
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Note (1): Correction for foreground Galactic extinction according to Schlafly &
Finkbeiner (infrared-based) recalibration of the Schlegel et al.
(1998ApJ...500..525S 1998ApJ...500..525S) infrared-based dust map. Magnitudes are derived
within 8 pixel apeture; aperture correction is applied.
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Acknowledgements:
Michele Cantiello, cantiello(at)oa-abruzzo.inaf.it
References:
Cantiello et al., Paper I 2015A&A...576A..14C 2015A&A...576A..14C, Cat. J/A+A/576/A14
(End) C. Michele [INAF, O.A. Abruzzo, Italy], P. Vannier [CDS] 06-Nov-2017