J/MNRAS/405/1293 Compact star clusters in M81 (Santiago-Cortes+, 2010)
Wide-field HST/ACS images of M81: the population of compact star clusters.
Santiago-Cortes M., Mayya Y.D., Rosa-Gonzalez D.
<Mon. Not. R. Astron. Soc., 405, 1293-1302 (2010)>
=2010MNRAS.405.1293S 2010MNRAS.405.1293S
ADC_Keywords: Galaxies, nearby ; Associations, stellar ; Photometry, HST
Keywords: catalogues - galaxies: individual: M81 - galaxies: spiral -
galaxies: star clusters
Abstract:
We study the population of compact star clusters (CSCs) in M81, using
the Hubble Space Telescope/Advanced Camera for Surveys (ACS) images in
the filters F435W, F606W and F814W covering, for the first time, the
entire optical extent of the galaxy. Our sample contains 435 clusters
of full width at half-maximum less than 10 ACS pixels (9pc). The
sample shows the presence of two cluster populations, a blue group of
263 objects brighter than B=22mag, and a red group of 172 objects,
brighter than B=24mag. On the basis of analysis of colour-magnitude
diagrams and making use of simple stellar population models,
Description:
The observations used in this work were carried out with the ACS Wide
Field Channel on board the HST. They were part of the projects with
proposal IDs 10250 (PI: John Huchra) and 10584 (PI: Andreas Zezas).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 70 434 *Observational properties of compact stellar
clusters of both blue and red groups
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Note on table3.dat: 172 red and 262 blue objects. Magnitude limit B<22mag.
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See also:
J/AJ/109/1055 : Globulars of M81 (Perelmuter+ 1995)
J/AJ/122/1330 : HST BVI photometry of M 81 star clusters (Chandar+, 2001)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Name (ANNANNNNN) (1)
11- 21 F11.7 deg RAdeg Right ascension in decimal degrees (J2000)
23- 32 F10.7 deg DEdeg Declination in decimal degrees (J2000)
34- 39 F6.3 mag Bmag.i ISOPHOT B magnitude
41- 46 F6.3 mag B-I ?=99.000 F435W-F814W (B-I) colour index
in Vega system (2)
48- 53 F6.3 mag B-R F435W-F606W (B-R) colour index
in Vega system (2)
55- 60 F6.3 mag Bmag.a Aperture B magnitude within a radius
of 10 pixels (0.5arcsec)
62- 65 F4.2 pix FWHM Peak size at full width at half-maximum (FWHM)
67- 70 F4.2 --- ell Ellipticity (1-b/a)
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Note (1): The first three digits indicate the ACS field number (Fig. 1),
the fourth letter indicates whether the cluster belongs to the blue
(B) or red (R) group, and the remaining part is the SExtractor
identification number of the source.
Note (2): The colours are calculated using the aperture magnitudes within a
radius of 10 pixels.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Dec-2010