J/ApJ/703/1872 Compact star clusters in the M31 disk (Vansevicius+, 2009)
Compact star clusters in the M31 disk.
Vansevicius V., Kodaira K., Narbutis D., Stonkute R., Bridzius A.,
Deveikis V., Semionov D.
<Astrophys. J., 703, 1872-1883 (2009)>
=2009ApJ...703.1872V 2009ApJ...703.1872V
ADC_Keywords: Clusters, globular ; Galaxies, nearby ; Photometry
Keywords: galaxies: individual (M31) - galaxies: star clusters -
stars: formation
Abstract:
We have carried out a survey of compact star clusters (apparent
size ≲3") in the southwest part of the M31 galaxy, based on the
high-resolution Suprime-Cam images (17.5'x28.5'), covering ∼15% of the
deprojected galaxy disk area. The UBVRI photometry of 285 cluster
candidates (V≲20.5mag) was performed using frames of the Local Group
Galaxies Survey. The final sample, containing 238 high probability
star cluster candidates (typical half-light radius rh∼1.5pc), was
selected by specifying a lower limit of rh≳0.15" (≳0.6pc). We
derived cluster parameters based on the photometric data and multiband
images by employing simple stellar population models. The clusters
have a wide range of ages from ∼5Myr (young objects associated with
24um and/or Hα emission) to ∼10Gyr (globular cluster
candidates), and possess mass in a range of 3.0≲log(m/m☉)≲4.3
peaking at m∼4000m☉. Typical age of these intermediate-mass
clusters is in the range of 30Myr≲t≲3Gyr, with a prominent peak at
∼70Myr. These findings suggest a rich intermediate-mass star cluster
population in M31, which appears to be scarce in the Milky Way galaxy.
Description:
We have identified high probability star cluster candidates (hereafter
star clusters) by visually inspecting the Subaru/Suprime-Cam V-band
mosaic image made from 5x2 minute individual exposures of the
17.5'x28.5' field, centered at J0040.9+4045. The characteristic full
width at half maximum (FWHM) of stellar images (point-spread function,
PSF) is 0.7".
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 60 238 Evolutionary and structural parameters of high
probability star cluster candidates in the
southwest part of the M31 disk
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See also:
B/subaru : Log of Subaru Prime Focus Camera Exposures (ADAC NAOJ, 2007)
J/PASP/122/745 : HST WFPC2 star clusters in M31. III. (Hodge+, 2010)
J/AJ/137/94 : Star clusters in M31 (Caldwell+, 2009)
J/A+A/507/1375 : HST/ACS VI data of M31 globular clusters (Perina+, 2009)
J/A+A/508/1285 : Metallicity estimates of M31 globular clusters (Galleti+,
20009)
J/ApJS/177/174 : Star clusters in M31 (Narbutis+, 2008)
J/PASP/120/1 : HST WFPC2 star clusters in M31. II. (Krienke, 2008)
J/A+A/471/127 : New globular clusters in M31 (Galleti+, 2007)
J/PASP/119/7 : HST WFPC2 star clusters in M31 (Krienke+, 2007)
J/PASJ/56/1025 : Compact star clusters in SW field of M31 (Kodaira+, 2004)
J/ApJ/559/851 : Young star cluster candidates in M31 (Williams+, 2001)
J/AJ/122/2458 : M31 globular clusters from HST (Barmby+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- [NVK2008] Candidate identification (KWNNN) (1)
7- 14 F8.5 deg RAdeg Right Ascension in decimal degrees (J2000) (1)
16- 23 F8.5 deg DEdeg Declination in decimal degrees (J2000) (1)
25- 29 F5.1 mag VMag Absolute V band magnitude (2)
31- 34 F4.2 [Myr] logt Log of the age
36- 39 F4.2 [Msun] logM Log of the mass
41- 44 F4.1 [-] [M/H] Metallicity
46- 49 F4.2 mag E(B-V) The B-V color excess (3)
51- 54 F4.1 pc rh Average half-light radius (4)
56- 60 A5 --- Note Object is discussed in the Appendix (5)
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Note (1): According to Narbutis et al. (2008, Cat. J/ApJS/177/174;
<[NVK2008] KWNNN> in Simbad).
Note (2): Corrected for aperture correction.
Note (3): Interstellar extinction in Milky Way plus M31.
Note (4): Average half-light radius in pc, where rh=(rhK+rhE)/2, derived
from the King and EFF models.
Note (5): Cross-reference with The Revised Bologna Catalog of M31 Globular
Clusters and candidates compiled by Galleti et al.
(2007, Cat. J/A+A/471/127; <Bol NNN> in Simbad) when available.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 02-Nov-2011