J/A+A/690/A164 YMCA (Yes, Magellanic Clouds Again) survey (Gatto+, 2024)
The YMCA (Yes, Magellanic Clouds Again) survey:
Probing the outer regions of the Magellanic system with VST.
Gatto M., Ripepi V., Bellazzini M., Tosi M., Cignoni M., Tortora C.,
Marconi M., Dall'Ora M., Cioni M.-R.L., Musella I., Schipani P., Spavone M.
<Astron. Astrophys. 690, A164 (2024)>
=2024A&A...690A.164G 2024A&A...690A.164G (SIMBAD/NED BibCode)
ADC_Keywords: Magellanic Clouds; Surveys; Clusters, open ; Photometry ; Optical
Keywords: surveys - Hertzsprung-Russell and C-M diagrams - galaxies: evolution -
galaxies: interactions - Magellanic Clouds -
galaxies: star clusters: general
Abstract:
The Magellanic Clouds (MCs) are the Milky Way's most massive dwarf
satellites. As they also represent the closest pair of galaxies in an
ongoing tidal interaction, while simultaneously infalling into the
Milky Way halo, they provide a unique opportunity to study in detail
an ongoing three-body encounter. We present the "YMCA (Yes,
Magellanic Clouds Again) survey: probing the outer regions of the
Magellanic system with VST" based on deep optical photometry carried
out with the VLT Survey Telescope (VST). YMCA targeted 110 square
degrees, in the g and i filters, in the periphery of both the MCs,
including a long strip in between the Large Magellanic Cloud (LMC) and
the Small Magellanic Cloud (SMC). The photometry of YMCA is
sufficiently deep (50% complete down to g≃23.5-24.0mag) to
allow for a detailed analysis of main-sequence stars in regions of the
MCs remained relatively unexplored at these faint magnitudes. The
resulting colour-magnitude diagrams reveal that the outskirts of the
MCs are predominantly characterized by intermediate-age and old
stellar populations, with limited or negligible evidence of recent
star formation. The analysis of the age distribution of star clusters
(SCs) within the surveyed area, both already known and newly
discovered candidates, hints at a close fly-by between the LMC and SMC
that occurred ≃2.5-3.0Gyr ago, in agreement with previous
results. We also report the discovery of candidate SCs with ages
within the so-called "age-gap", questioning its real existence.
Description:
The data used in this work were obtained with the VLT Survey Telescope
(VST) in the context of the YMCA (Yes, Magellanic Clouds Again)
survey.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
clusters.dat 109 25 Cluster properties
catalog.dat 81 6467819 YMCA catalogue (table 2)
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Byte-by-byte Description of file: clusters.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- ID Cluster name, YMCA-NNNN
11- 22 F12.8 deg RAdeg Right ascension (J2000.0)
24- 35 F12.8 deg DEdeg Declination (J2000.0)
37- 40 F4.2 arcmin R Cluster radius
42- 46 F5.2 [yr] logt Cluster Age
48- 51 I4 --- Nstars Number of stars within the cluster radius
53- 57 F5.1 --- G Parameter defined in Eq.2 of the paper
59- 62 I4 arcmin-2 n0 Central number surface density
64- 65 I2 arcmin-2 e_n0 Uncertainty on n0
67- 70 F4.2 arcmin rc Core radius of the cluster
72- 75 F4.2 arcmin e_rc Uncertainty on the core radius
77- 80 F4.1 pc rcpc Core radius of the cluster given in parsec
82- 84 F3.1 pc e_rcpc Uncertainty on the core radius given in parsec
86- 90 A5 --- Tile Tile where the SC resides
92 A1 --- Flag [ABC] Flag assessing the reliability
of the SC (1)
94-109 A16 --- Simbad Additional IDs as reported in SIMBAD
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Note (1): A and B represent the highest and the intermediate confidence level;
C reports SCs which necessitate deeper follow-up images to be confirmed.
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Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 18 E18.13 deg RAdeg [] Right ascension (J2000.0)
20- 30 F11.7 deg DEdeg Declination (J2000.0)
32- 41 F10.7 mag gmag Calibrated magnitude in the g-filter
43- 50 E8.4 mag e_gmag Uncertainty of the magnitude in the g-filter
52- 61 F10.7 mag imag Calibrated magnitude in the i-filter
63- 68 E6.4 mag e_imag Uncertainty of the magnitude in the i-filter
70- 74 F5.2 --- chi CHI output parameter of DAOPHOTIV/ALLSTAR
76- 81 F6.3 --- sharp SHARP output parameter of DAOPHOTIV/ALLSTAR
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Acknowledgements:
Massimiliano Gatto, massimiliano.gatto(at)inaf.it
(End) Massimiliano Gatto [INAF, Italy], Patricia Vannier [CDS] 16-Jul-2024