J/A+A/534/A96 Spitzer photometry of YSC in M33 (Sharma+, 2011)
The population of young stellar clusters throughout the disk of M33.
Sharma S., Corbelli E., Giovanardi C., Hunt L.K., Palla F.
<Astron. Astrophys. 534, A96 (2011)>
=2011A&A...534A..96S 2011A&A...534A..96S
ADC_Keywords: Galaxies, nearby ; Associations, stellar ; Photometry, infrared
Keywords: galaxies: individual: M33 - galaxies: ISM -
galaxies: star clusters: general - galaxies: star formation
Abstract:
The properties of young stellar clusters (YSCs) in M33, identified
from the center out to about twice the size of the bright star-forming
disk, are investigated to determine possible spatial and time
variations of the star formation process in this Local Group blue
galaxy.
915 MIR sources have been extracted from the Spitzer 24um image.
Upon inspection of Hα and GALEX images and exclusion of evolved
AGB stars, a sample of 648 objects is selected as candidate YSCs and
their luminosity function is examined. The spectral energy
distribution of each object, based on aperture photometry, is compared
with Starburst99 models to derive age, mass and AV of individual
clusters. In the analysis we allow for different values of the upper
mass cutoff of the stellar initial mass function (IMF), the porosity
of the ISM, and the dustiness of HII regions. We also examine the
influence of different dust models and include corrections for
incompleteness of the IMF.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 33 407 Young Stellar Clusters in Verley et al. 2007
(Cat. J/A+A/476/1161)
table2.dat 67 400 Additional 24µm source catalogue and YSCs
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See also:
J/AJ/110/2739 : H-alpha emitting regions in M33 (Calzetti+ 1995)
J/A+A/476/1161 : Spitzer photometry of M33 (Verley+, 2007)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/514] Sequential number of 24 micron source
in M33, <[VHC2007b] IR NNN> in Simbad
5- 13 F9.6 deg RAdeg Right ascension in decimal degrees (J2000)
15- 23 F9.6 deg DEdeg Declination in decimal degrees (J2000)
25- 28 F4.1 arcsec Size Source size, semi-major axis of the ellipse
fitted to the 8σ isophote
30- 33 F4.2 kpc RG Galactocentric radius
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [516/915] Sequential number of 24 micron
source in M33, <[VHC2007b] IR NNN> in Simbad
5- 13 F9.6 deg RAdeg Right ascension in decimal degrees (J2000)
15- 23 F9.6 deg DEdeg Declination in decimal degrees (J2000)
25- 28 F4.1 arcsec Size Source size, semi-major axis of the ellipse
fitted to the 8σ isophote
30- 37 F8.3 mJy F24um Spitzer/MIPS 24µm flux
39- 43 F5.3 mJy e_F24um rms uncertainty on F24um
45- 51 F7.3 mJy F8um ?=- Spitzer/IRAC 8µm flux
53- 57 F5.3 mJy e_F8um ?=- rms uncertainty on F8um
59- 63 F5.2 kpc RG Galactocentric radius
65- 67 A3 --- Note [YSC] YSC is for sources classified as Young
Stellar Clusters and included in the analysis
of YSC properties presented in the paper (1)
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Note (1): Blank when the source cannot be classified as YSC because is outside
the boundaries of one of the maps used for the identification of YSCs.
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Acknowledgements:
Edvige Corbelli, edvige(at)arcetri.astro.it
References:
Verley et al., Paper I 2007A&A...476.1161V 2007A&A...476.1161V, Cat. J/A+A/476/1161
(End) Patricia Vannier [CDS] 13-Sep-2011