J/A+A/464/495 UBVI photometry of NGC 45 star clusters (Mora+, 2007)
Imaging of star clusters in unperturbed spiral galaxies with the Advanced
Camera for Surveys. I. The low luminosity galaxy NGC 45.
Mora M.D., Larsen S.S., Kissler-Patig M.
<Astron. Astrophys., 464, 495-505 (2007)>
=2007A&A...464..495M 2007A&A...464..495M
ADC_Keywords: Galaxies, nearby ; Associations, stellar ; Photometry, UBVRI
Keywords: galaxies: individual: NGC 45 - galaxies: star clusters -
galaxies: photometry
Abstract:
Star clusters are present in almost all types of galaxies. Here we
investigate the star cluster population in the low-luminosity,
unperturbed spiral galaxy NGC 45, which is located in the nearby
Sculptor group. Both the old (globular) and young star-cluster
populations are studied.
Previous ground-based observations have suggested that NGC 45 has few
if any "massive" young star clusters. We aim to study the population
of lower-mass "open" star clusters and also identify old globular
clusters that could not be distinguished from foreground stars in the
ground-based data.
Star clusters were identified using UBVI imaging from the Advanced
Camera for Surveys (ACS) and the Wide Field Planetary Camera 2 (WFPC2)
on board the Hubble Space Telescope. From broad band colors and
comparison with simple stellar population (SSP) models assuming a
fixed metallicity, we derived the age, mass, and extinction. We also
measured the radius for each star cluster candidate.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables.dat 165 47 Young star clusters (tables 2-4 of the paper)
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Byte-by-byte Description of file: tables.dat
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Bytes Format Units Label Explanations
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1- 2 I2 -- [MLK2007] Sequential number
4 I1 h RAh Right ascension (J2000)
5 A1 --- --- [:]
6- 7 I2 min RAm Right ascension (J2000)
8 A1 --- --- [:]
9- 13 F5.2 s RAs [0:100] Right ascension (J2000) (1)
15 A1 --- DE- Declination sign (J2000)
16- 17 I2 deg DEd Declination sign (J2000)
18 A1 --- --- [:]
19- 20 I2 arcmin DEm Declination sign (J2000)
21 A1 --- --- [:]
22- 26 F5.2 arcsec DEs Declination sign (J2000)
28- 33 F6.3 mag Bmag B (F435W) magnitude
35- 39 F5.3 mag e_Bmag rms uncertainty on Bmag
41- 46 F6.3 mag Vmag V (F555W) magnitude
48- 52 F5.3 mag e_Vmag rms uncertainty in Vmag
54- 59 F6.3 mag Imag I (F814W) magnitude
61- 65 F5.3 mag e_Imag rms uncertainty on Imag
67- 72 F6.3 mag Umag ? U (F336W) magnitude
74- 78 F5.3 mag e_Umag ? rms uncertainty on Umag
80- 85 F6.3 pix FWHM FWHM derived using SExtractor for F435W band
87- 91 F5.3 pix FWHMB FWHM derived using ISHAPE for F435W band
93- 97 F5.3 pix FWHMV FWHM derived using ISHAPE for F555W band
99-103 F5.3 pix FWHMI FWHM derived using ISHAPE for F814W band
105-108 F4.2 mag AV1 ? Extinction derived for metallicity model 1
109 A1 --- n_AV1 [*] *: best fit value derived using SExtractor
110-113 F4.2 mag AV2 ? Extinction derived for metallicity model 2
114 A1 --- n_AV2 [*] *: best fit value derived using SExtractor
115-118 F4.2 mag AV3 ? Extinction derived for metallicity model 3
119 A1 --- n_AV3 [*] *: best fit value derived using SExtractor
120-123 F4.2 mag AV4 ? Extinction derived for metallicity model 4
124 A1 --- n_AV4 [*] *: best fit value derived using SExtractor
125-128 F4.2 [yr] logAge1 ? Cluster age derived for metallicity model 1
129 A1 --- n_logAge1 [*] *: best fit value derived using SExtractor
130-133 F4.2 [yr] logAge2 ? Cluster age derived for metallicity model 2
134 A1 --- n_logAge2 [*] *: best fit value derived using SExtractor
135-139 F5.2 [yr] logAge3 ? Cluster age derived for metallicity model 3
140 A1 --- n_logAge3 [*] *: best fit value derived using SExtractor
141-144 F4.2 [yr] logAge4 ? Cluster age derived for metallicity model 4
145 A1 --- n_logAge4 [*] *: best fit value derived using SExtractor
146-149 F4.2 [solMass] logM1 ? Cluster mass derived for metallicity model 1
150 A1 --- n_logM1 [*] *: best fit value derived using SExtractor
151-154 F4.2 [solMass] logM2 ? Cluster mass derived for metallicity model 2
155 A1 --- n_logM2 [*] *: best fit value derived using SExtractor
156-159 F4.2 [solMass] logM3 ? Cluster mass derived for metallicity model 3
160 A1 --- n_logM3 [*] *: best fit value derived using SExtractor
161-164 F4.2 [solMass] logM4 ? Cluster mass derived for metallicity model 4
165 A1 --- n_logM4 [*] *: best fit value derived using SExtractor
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Note (1): For [MLK2007] 10, the printed position is erroneous. It has been
corrected into 0:14:04.67 -23:09:22.27 (from author)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 28-Sep-2007