J/A+A/578/A51 Near-IR photometry of AGB stars in IC 1613 (Chun+, 2015)
Near-infrared photometric properties of asymptotic giant branch stars in dwarf
irregular galaxy IC 1613.
Chun S.-H., Kang M., Kim J.-W., Sohn Y.-J.
<Astron. Astrophys. 578, A51 (2015)>
=2015A&A...578A..51C 2015A&A...578A..51C
ADC_Keywords: Galaxies, photometry ; Galaxies, IR ; Stars, giant ; Stars, carbon
Keywords: galaxies: individual: IC 1613 - galaxies: irregular -
stars: AGB and post-AGB
Abstract:
We investigated the photometric properties of asymptotic giant branch
(AGB) stars of dwarf irregular galaxy IC 1613 and its metallicity.
We used near-infrared JHKs photometric data obtained with the WIRCam
array on Canada-France-Hawaii Telescope (CHFT). The optical gi imaging
data of previous study were cross-matched with ours to distinguish the
stellar populations in the galaxy and to select the AGB stars. We also
separated the C stars from the M-giant stars in the JHKs color-color
diagram. We identified 140 C stars and 306 M-giant stars in IC 1613.
The (J-Ks) color histogram of AGB stars shows the main peak of M-giant
stars and the red tail of C stars.
The broad color distribution of M-giant stars and the isochrones in
color magnitude diagram indicate that IC 1613 has a wide range of
intermediate-age stars. We also know that most C stars were formed
over the past 2-8Gyr according the M_bol-age relation.
The C/M ratio of 0.46±0.05 was estimated and [Fe/H] abundance of
-1.23±0.06 was derived from the C/M ratio. Radial distributions of
C/M ratio and metallicity show the shallow trend of the negative
metallicity gradient from the center. The local C/M ratio also
indicates that the HI cavity has higher C/M values than the bright HI
spot and HI gas region. However, the low [Fe/H] value near the central
region of the galaxy is likely to be caused by the change in age of
the dominant stellar population according to the radial distance, not
the real metallicity variation. It might also be that relatively
younger and metal-rich C stars are concentrated in the center of the
galaxy, while the M-giant stars were homogeneously distributed from
the center to the borders of the galaxy.
Description:
The sky position, magnitudes and photometric errors in J, H, and Ks
band for the identified AGB stars in IC 1613 were presented.
The identification of M-giant and C-stars also provided.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 70 446 Sky position and photometric measurement for
446 AGB stars in IC 1613
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See also:
J/A+A/363/29 : Variable stars in IC 1613 (Antonello+, 2000)
J/AJ/119/2780 : C stars in IC 1613 (Albert+, 2000)
J/AcA/51/221 : OGLE-II. Cepheids in IC 1613 (Udalski+, 2001)
J/A+A/367/759 : Variable stars in IC 1613 (Mantegazza+, 2001)
J/A+A/445/901 : BV(RI)c bands of Cepheids in IC 1613 (Antonello+, 2006)
J/A+A/493/1075 : IC 1613 & NGC 3109 C stars JKs photometry (Battinelli+ 2009)
J/A+A/502/1015 : OB associations in IC 1613 (Garcia+, 2009)
J/A+A/523/A23 : Properties of OB associations in IC 1613 (Garcia+, 2010)
J/A+A/573/A84 : JHK photometry of IC 1613 AGB (Sibbons+, 2015)
J/ApJ/712/1259 : LCID project. II. Variables in IC1613 (Bernard+, 2010)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID [475/22374] ID number of identified AGB stars
7- 14 F8.5 deg RAdeg Right Ascension J2000 (degrees)
16- 23 F8.5 deg DEdeg Declination J2000 (degrees)
25- 31 F7.4 mag Jmag [17.1/20.2] J band magnitude
33- 38 F6.4 mag e_Jmag [0.02/0.1] Error of J magnitude
40- 46 F7.4 mag Hmag [16.1/19.2] H band magnitude
48- 53 F6.4 mag e_Hmag [0.02/0.1] Error of H magnitude
55- 61 F7.4 mag Ksmag [15.5/18.2] Ks band magnitude
63- 68 F6.4 mag e_Ksmag [0.01/0.1] Error of Ks magnitude
70 A1 --- cl Classification of C-star and M-giant
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Acknowledgements:
Sang-Hyun Chun, shyunc.m(at)gmail.com
(End) Patricia Vannier [CDS] 04-May-2015