J/A+A/517/A50 Ages & luminosities of young SMC/LMC star clusters (Glatt+, 2010)
Ages and luminosities of young SMC/LMC star clusters and the recent star
formation history of the Clouds.
Glatt K., Grebel E.K., Koch A.
<Astron. Astrophys. 517, A50 (2010)>
=2010A&A...517A..50G 2010A&A...517A..50G
ADC_Keywords: Magellanic Clouds ; Associations, stellar ; Magnitudes
Keywords: Magellanic Clouds - galaxies: clusters: general -
galaxies: evolution
Abstract:
In this paper we discuss the age and spatial distribution of young
(age<1Gyr) SMC and LMC clusters using data from the Magellanic Cloud
Photometric Surveys. Luminosities are calculated for all age-dated
clusters. Ages of 324 and 1193 populous star clusters in the Small and
the Large Magellanic Cloud have been determined fitting Padova and
Geneva isochrone models to their resolved color-magnitude diagrams.
The clusters cover an age range between 10Myr and 1Gyr in each galaxy.
For the SMC a constant distance modulus of (m-M)0=18.90 and a
metallicity of Z=0.004 were adopted. For the LMC, we used a constant
distance modulus of (m-M)0=18.50 and a metallicity of Z=0.008.
For both galaxies, we used a variable color excess to derive the
cluster ages. We find two periods of enhanced cluster formation in
both galaxies at 160Myr and 630Myr (SMC) and at 125Myr and 800Myr
(LMC). We present the spatially resolved recent star formation history
of both Clouds based on young star clusters. The first peak may have
been triggered by a close encounter between the SMC and the LMC. In
both galaxies the youngest clusters reside in the supergiant shells,
giant shells, the inter-shell regions, and toward regions with a high
Hαcontent, suggesting that their formation is related to
expansion and shell-shell interaction. Most of the clusters are older
than the dynamical age of the supergiant shells. No evidence for
cluster dissolution was found. Computed V band luminosities show a
trend for fainter magnitudes with increasing age as well as a trend
for brighter magnitudes with increasing apparent cluster radii.
Description:
Ages and luminosities for 324 SMC and 1193 LMC star clusters. For each
star cluster reddening, radius, log(age(yr)), age uncertainties, right
ascension, declination, V-band magnitudes, error(V), and
cross-identification are given.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
lmc.dat 111 1194 LMC cluster ages, luminosities, reddenings,
radii, cross-identifications
smc.dat 98 322 SMC cluster ages, luminosities, reddenings,
radii, cross-identifications
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See also:
J/A+AS/110/533 : Clusters and field stars in LMC. I. (Linde+, 1995)
J/AJ/116/723 : LMC star clusters ages and metallicity (Bica+ 1998)
J/AcA/49/521 : OGLE LMC star clusters BVI photometry (Pietrzynski+, 1999)
J/MNRAS/386/1380 : BVRI photometry of LMC star clusters (Kumar+, 2008)
J/A+A/501/585 : CT1 photometry in five LMC star clusters (Piatti+, 2009)
J/A+A/503/469 : Compact clusters in LMC catalogue of stars (Liu+, 2009)
Byte-by-byte Description of file: lmc.dat smc.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Name Identification number (LMCNNNN or SMCNNNN)
8 A1 --- n_Name [*] Note on Name (1)
10- 14 F5.3 mag E(B-V) Foreground reddening
16- 20 F5.3 arcmin R Radius (2)
22 A1 --- l_Age Limit flag on log(Age)
23- 26 F4.2 [yr] Age Cluster age in logarithmic scale
27 A1 --- --- [/]
28- 31 F4.2 [yr] Age2 ? Second value of cluster age in
logarithmic scale
33 I1 --- q_Age ?=- Class for Age uncertainties (3)
36 I1 h RAh Right ascension (J2000)
38- 39 I2 min RAm Right ascension (J2000)
41- 42 I2 s RAs [0/60] Right ascension (J2000)
44 A1 --- DE- Declination sign (J2000)
45- 46 I2 deg DEd Declination (J2000)
48- 49 I2 arcmin DEm Declination (J2000)
51- 52 I2 arcsec DEs [0/60] Declination (J2000)
54- 59 F6.3 mag Vmag V-band magnitude
61- 64 F4.2 mag e_Vmag Uncertainties of V-band magnitude
66-111 A46 --- Cross-ID Cross-Identification(s)
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Note (1): Identification numbers with an asterix are possible double/multiple
populations (Dieball et al., 2002, Cat. J/A+A/391/547)
Note (2): Radii adopted from Bica et al., 2008, Cat. J/MNRAS/389/678.
Note (3): Class code as follows:
1 = objects having Δ(log(age(yr)))<0.3
2 = objects having 0.3 <Δ(Log(Age(yr)))<0.5
3 = objects having Δ(Log(Age(yr)))>0.5
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Acknowledgements:
Katharina Glatt, kglatt(at)ari.uni-heidelberg.de
History:
* 09-Aug-2010: Original version
* 05-Apr-2011: some names corrected
(End) Patricia Vannier [CDS] 08-Apr-2010